UNP College of Medicine Medical Biochemistry Laboratory Manual PDF

BV J M MEDICAL BIOCHEMISTRY D LABORATORY MANUAL RM T 1 / 109  CONTENTS BV Safety in the Laboratory Laboratory Activity 01 Laboratory Equipment Laboratory Activity 02...

BV J M MEDICAL BIOCHEMISTRY D LABORATORY MANUAL RM T 1 / 109  CONTENTS BV Safety in the Laboratory Laboratory Activity 01 Laboratory Equipment Laboratory Activity 02 Specimen Collection Laboratory Activity 03 Water and Acid-Base Equilibria Laboratory Activity 04 Properties of Amino Acids and Proteins Laboratory Activity 05A Sickling Test J Laboratory Activity 05B Enzyme Function Laboratory Activity 06 Detection of Carbohydrates Laboratory Activity 07 Detection of Pentoses Laboratory Activity 08 Cytochemical Stain Demonstrating Glycogen Detection of Lactic Acid Using Uffelman’s Reaction M Laboratory Activity 09 Laboratory Activity 10 Determination of Serum Triacylglycerol Concentration Laboratory Activity 11 Phosphatidylcholine Hydrolysis Laboratory Activity 12 Determination of Serum Cholesterol Concentration Laboratory Activity 13 Determination of Blood Urea Nitrogen Laboratory Activity 14 Determination of Amino Acid Metabolites Laboratory Activity 15 Creatinine Assay D Laboratory Activity 16 Uric Acid Determination Laboratory Activity 17 Qualitative Reactions of Insulin Laboratory Activity 18 Blood Glucose Determination Laboratory Activity 19A Qualitative Reaction of Tocopherol Laboratory Activity 19B Qualitative Reaction of Ascorbic Acid Laboratory Activity 20 White Blood Cell and Differential Counts RM T 2 / 109  SAFETY in the LABORATORY Best practices Do not keep food or beverages, as well as personal belongings like jackets and bags, inside the laboratory. Eating, drinking, smoking, and applying cosmetics should only take place outside the laboratory premises. Do not place items such as pens, pencils, or gum in your mouth while inside the laboratory, regardless of whether gloves are being worn or not. After handling biological materials and/or animals, it is essential to wash your hands thoroughly, preferably using warm running water and soap, before exiting the laboratory or if you suspect that your hands are contaminated. Make sure that open flames or heat sources are never placed in proximity to flammable supplies and are BV never left unsupervised. Make sure to cover any cuts or broken skin before entering the laboratory. Before entering the laboratory, confirm the availability of sufficient laboratory equipment and consumables, such as reagents, personal protective equipment (PPE), and disinfectants, ensuring they are appropriate for the planned activities. Make sure to store supplies safely and in accordance with storage instructions to minimize accidents and incidents like spills, trips, and falls. Ensure that all biological agents, chemicals, and radioactive materials are correctly labeled. J Shield written documents from contamination by utilizing barriers like plastic coverings, especially for those that might need to be taken out of the laboratory. Make sure to conduct work with diligence and without rushing. Refrain from working when feeling fatigued. M Maintain the work area in an orderly, clean, and clutter-free condition, eliminating non-essential objects and materials. Disallow the use of earphones as they can distract personnel and prevent them from hearing equipment or facility alarms. Cover or remove any jewelry that might tear gloves, be easily contaminated, or act as fomites. Consider cleaning and decontaminating jewelry or spectacles if they are worn regularly. Avoid using portable electronic devices, such as mobile phones, tablets, laptops, flash drives, memory D sticks, cameras, or other similar devices, unless they are specifically needed for the laboratory procedures being conducted. Store portable electronic devices in locations where they are unlikely to become contaminated or serve as fomites for transmitting infections. If these devices must be in close proximity to biological agents, either shield them with a physical barrier or decontaminate them before exiting the laboratory. RM Technical Procedures Avoiding Inhalation of Biological Agents Employ proper techniques to reduce the generation of aerosols and droplets during specimen manipulation. This involves avoiding forcefully expelling substances from pipette tips into liquids, overly vigorous mixing, and haphazardly flipping open tubes. When using pipette tips for mixing, ensure this is done slowly and meticulously. Additionally, briefly centrifuging mixed tubes before opening them can aid in moving any liquid away from the cap. Refrain from placing loops or similar instruments directly into an open heat source, such as a flame, as this may lead to the splattering of infectious material. Whenever feasible, utilize disposable transfer loops that eliminate the need for resterilization. Alternatively, consider using an enclosed electric microincinerator for sterilizing metal transfer loops, which can be equally effective. T Avoiding Ingestion of Biological Agents and Contact with Skin and Eyes Always wear disposable gloves when handling specimens that are known or reasonably expected to contain biological agents. Disposable gloves should not be reused. Refrain from touching the face with gloved hands. After use, remove gloves using aseptic techniques and wash hands. During operations where splashing may occur, such as mixing disinfectant solutions, ensure to shield or protect the mouth, eyes, and face accordingly. Ensure hair is properly secured to prevent contamination. Apply an appropriate dressing to cover any broken skin. 3 / 109  Forbid the practice of pipetting by mouth. Avoiding Injection of Biological Agents Whenever feasible, substitute glassware with plastic alternatives. If necessary, utilize scissors with blunt or rounded tips instead of pointed ones. If glassware is necessary, regularly inspect it for any signs of damage such as breakage, cracks, or chips, and discard it if any such issues are detected. Utilize ampoule openers for the safe handling of ampoules. Reduce the risk associated with syringes or needles by opting for blunt syringe needles, alternative devices, or engineered sharp safety devices whenever feasible. However, it's important to note that improper handling of sharp safety devices can also pose risks. Do not use syringes with needles as a substitute for pipetting devices under any circumstances. BV Do not cap, clip, or remove needles from disposable syringes under any circumstances. Dispose of any sharp materials (such as needles, needles combined with syringes, blades, and broken glass) in containers that are puncture-proof or puncture-resistant, and have sealed covers. These disposal containers should not be filled to capacity (at most three-quarters full), must never be reused, and should not be disposed of in landfills. Preventing Dispersal of Biological Agents Dispose of specimens and cultures by placing them in leak-proof containers with securely fastened lids before discarding them in designated waste receptacles. J Position waste containers, ideally made of unbreakable materials like plastic or metal, at each workstation. Regularly empty waste containers and ensure proper disposal of waste by securely disposing of it. Make sure that all waste is appropriately labeled. Consider opening tubes using a pad or gauze soaked in disinfectant. M Disinfect work surfaces using an appropriate disinfectant at the conclusion of work procedures and in the event of any material spills. When employing disinfectants, confirm that the disinfectant is effective against the handled agents and allow it to remain in contact with waste materials for the recommended duration, as specified by the particular disinfectant being used. D Facility Adequate space must be allocated to ensure the safe execution of laboratory tasks as well as for cleaning and maintenance purposes. Each laboratory room must be equipped with designated hand-washing basins operated by a hands-free mechanism, ideally positioned near the exit door. Access to the laboratory must be restricted. Entrance doors to the laboratory should include vision panels RM (to prevent accidents when opening), suitable fire ratings, and preferably self-closing. Doors should be labeled appropriately with international biohazard warning symbols wherever biohazardous materials are handled and stored. The walls, floors, and furniture in the laboratory must be smooth, easy to clean, resistant to liquid permeation, and capable of withstanding the chemicals and disinfectants typically utilized in the laboratory. Laboratory bench tops should be impermeable to water and resilient against disinfectants, acids, alkalis, organic solvents, and moderate heat. Laboratory furniture must be suitable for its intended use. Open spaces between and underneath benches, cabinets, and equipment must be easily accessible for cleaning purposes. The lighting in the laboratory must be sufficient for all tasks. Daylight should be efficiently utilized to conserve energy. Unwanted reflections and glare should be minimized. Emergency lighting must be adequate to T enable the safe cessation of work and the secure evacuation of the laboratory. In cases where laboratory ventilation is available (including heating/cooling systems, particularly fans and local cooling split-system air conditioning units – especially in retrofit situations), it should be designed to maintain safe working conditions without compromising airflow. Attention should be paid to airflow speeds and directions, with efforts made to prevent turbulent airflow. This consideration also applies to natural ventilation. The laboratory storage space should be sufficient to accommodate supplies needed for immediate use, preventing clutter on benchtops and in aisles. Additional long-term storage space, conveniently situated outside of the laboratory room or space, should be taken into account. 4 / 109  Adequate space and facilities must be available for the safe handling and storage of chemicals and solvents, radioactive materials, as well as compressed and liquefied gases, if utilized. Provisions for storing food and beverages, personal belongings, jackets, and outerwear must be available outside the laboratory. Areas designated for eating and drinking should be situated outside the laboratory. First-aid facilities should be easily accessible and appropriately equipped/stocked. Suitable decontamination methods for waste, such as disinfectants and autoclaves, should be conveniently located near the laboratory. Waste management considerations should be incorporated into the design. Safety systems must encompass fire, electrical emergencies, and emergency/incident response facilities, as determined by risk assessment. A dependable and sufficient electricity supply and lighting must be in place to ensure safe egress. BV Emergency scenarios must be factored into the design, as outlined in the local risk assessment, and should take into account the geographical and meteorological context. Fire safety and the risk of flooding must be taken into consideration. Training to be Implemented for Laboratory Personnel Training Areas to be Covered General familiarization and Mandatory for ALL personnel, an introduction to: awareness training Laboratory layout, features and equipment Laboratory code(s) of practice J Applicable local guidelines Safety or operations manual(s) Institutional policies Local and overarching risk assessments Legislative obligations M Emergency/incident response procedures Job-specific training Training will be determined based on job function, and the training requirements may differ among personnel with the same job title but performing different duties. All personnel engaged in the manipulation of biological agents must undergo GMPP (good microbiological practice and D procedure) training. Competency and proficiency assessments should be utilized to identify any additional specific training needs, such as through observation and/or qualification. Verification of proficiency in any procedure must occur before working independently, potentially necessitating a RM mentorship period. Competencies must undergo regular review, and refresher training should be completed accordingly. Information regarding new procedures, equipment, technologies, and knowledge must be conveyed to relevant personnel as soon as it becomes available. Safety and security training Mandatory for ALL personnel: Understanding the hazards present in the laboratory and their associated risks Safe working procedures Security measures T Emergency preparedness and response Biological Samples or Specimens All samples should be regarded as potentially able to transmit an infectious agent. During processing, samples must be handled within a biological containment hood (Biosafety Level 2). 5 / 109 Storing Specimens Specimens Must be Stored in Containers That are: Constructed with sufficient strength, integrity, and capacity to contain the specimen. When the cap or stopper is properly applied, it should be leak-proof. Whenever feasible, constructed from plastic. Devoid of any biological material on the exterior of the packaging. Accurately labeled, marked, and documented to aid in identification, and Constructed from a suitable material for the intended storage purpose. Decontamination and Waste Management Classifications of Separated Laboratory Waste Materials and Their Suggested Handling BV Category of Laboratory Waste Material Treatment Uncontaminated (non-infectious) material Items can be reused, recycled, or discarded as general municipal waste. Contaminated sharps (hypodermic needles, Items should be gathered in puncture-resistant scalpels, knives, and broken glass) containers equipped with lids and treated as infectious. Contaminated material for reuse or recycling Items must undergo initial decontamination (chemical or physical) followed by washing; J subsequently, they can be treated as uncontaminated (non-infectious) material. Contaminated material for disposal Either decontaminate on-site or securely store before transporting to another location for M decontamination and disposal. Contaminated material for incineration Either incinerate on-site or securely store before transporting to another location for incineration. Liquid waste (including potentially contaminated Items should undergo decontamination before liquids) for disposal in the sanitary sewer system being disposed of in the sanitary sewer. Chemical Disinfection D Chemical disinfection is a decontamination method that entails applying a chemical or combination of chemicals to an inanimate surface or material to deactivate viable biological agents or diminish their count to a safe level. Disinfectants are typically the preferred choice for surface decontamination. However, regular cleaning of floors, walls, equipment, and furniture is generally not mandated as a fundamental biosafety requirement. RM Disinfectants ought to be employed following a spill or in situations where contamination is known or suspected. Surface disinfection (and where relevant, material disinfection) should also be conducted after work has been finished on the bench and regularly as part of a cleaning regimen. Disinfectants can also serve for decontaminating contaminated liquids. Non-biological risks associated with chemical disinfectants should also be taken into account, and suitable non-biological risk mitigation measures implemented. For instance, numerous chemical disinfectants may pose risks to humans, animals, or the environment, or present fire or explosion hazards. Consequently, chemical disinfectants must be carefully chosen, stored, handled, used, and disposed of in accordance with manufacturers' instructions. Special attention is necessary for the use and storage of such chemicals in tropical regions, where high ambient temperatures and sunlight exposure may diminish their shelf life. T Personal Protective Equipment (PPE) should be employed to minimize the risk of personnel exposure to both chemical hazards and any present biological agents. Detailed instructions on PPE necessities can be found in safety data sheets, also known as material safety data sheets, supplied by the manufacturer. Autoclaving When utilized properly, autoclaving stands as the most efficient and dependable method for sterilizing laboratory materials and decontaminating waste materials by eliminating or neutralizing biological agents. Incineration A frequently employed method for inactivation is incineration, which also serves as a disposal method, including for animal carcasses. 6 / 109 Personal Protective Equipment Laboratory Coats It’s essential to wear laboratory coats to prevent personal clothing from being splashed or contaminated by biological agents. These coats should feature long sleeves, preferably with fitted cuffs, and must be worn closed at all times. Rolling up sleeves is strictly prohibited. Coats should be of sufficient length to cover the knees but should not drag on the floor. Whenever possible, laboratory coats should be made of splash-resistant fabric and should overlap at the front. They can be either reusable or disposable, but if reusable coats are used, laundering must be performed by the laboratory or a specialized contractor. Laundering should be conducted regularly, and any visibly BV contaminated coats should be autoclaved before laundering. Laboratory coats must be worn only in designated areas and appropriately stored when not in use; they should not be hung on top of other coats or placed in lockers or hooks with personal items. Personnel are not permitted to take laboratory coats home. Avoid wearing shorts. Footwear Laboratory personnel must wear appropriate footwear designed to minimize slips, trips, and potential injuries from falling objects and exposure to biological agents. J The footwear should provide coverage for the top of the foot and should be well-fitted and comfortable to ensure personnel can perform tasks without fatigue or distraction. Avoid wearing open-toed shoes. Gloves Disposable gloves suitable for procedures involving anticipated or accidental contact with blood, M bodily fluids, and other potentially infectious materials must be worn. These gloves should not be disinfected or reused, as exposure to disinfectants and prolonged wear can compromise their integrity, thereby reducing user protection. It is essential to inspect gloves before use to ensure they are intact. Eye protection Safety glasses, goggles, face shields (visors), or other protective devices must be worn whenever D necessary to shield the eyes and face from splashes, impacts, and artificial ultraviolet radiation. Eye protection should be cleaned after each use, and if splashed, it must be decontaminated with an appropriate disinfectant. Personal prescription glasses (spectacles) should not be relied upon as eye protection as they do not adequately cover the area around the eyes, particularly the sides of the head. Personnel requiring corrective lenses must obtain specialized prescription safety glasses. Some goggles are available with recesses that allow RM glasses to be worn underneath them. Respiratory Protection Respiratory protection is typically not necessary for safeguarding against biological agents as part of the fundamental requirements. However, if a risk assessment determines the necessity of respiratory protection, it is regarded as an escalated control measure. Nevertheless, there might be situations where respiratory protection is warranted for reasons unrelated to biological hazards, such as chemical exposure or allergens, based on assessments for non-biological hazards. Recognize Hazards Ensure that every container is labeled correctly. Exercise caution to prevent skin or other bodily tissue contact, as all solutions are deemed harmful. T The reagents are toxic and require careful handling and disposal. If there is contact with reagents, flush the affected area with water and promptly inform the tutor. Reference Laboratory Biosafety Manual 4th Edition World Health Organization 21 December 2020 7 / 109  LABORATORY ACTIVITY 01 LABORATORY EQUIPMENT Analytical Balance An analytical balance is a precise weighing instrument used in scientific laboratories and various industries to measure the mass of substances with exceptional accuracy. It is designed to provide exact measurements in small increments, typically to four or five decimal places (0.0001 or 0.00001 grams). Analytical balances are indispensable tools in chemistry, pharmaceuticals, biology, and materials science, where exact measurements are critical. BV J M Bunsen Burner A Bunsen burner is a standard laboratory apparatus used for heating, sterilizing, and combustion processes D in various scientific and industrial settings. Named after its inventor, German chemist Robert Wilhelm Bunsen, it consists of a metal tube attached to a gas source, typically natural gas, methane, or propane, with an adjustable air intake. RM T 8 / 109 Capillary Blood Collection Tubes Capillary blood collection tubes, also known as capillary tubes or microtainers, are small, narrow tubes used to collect small volumes of blood from a capillary puncture site, typically the fingertip or heel. These tubes are designed for point-of-care testing, requiring only a small sample volume, such as in glucose monitoring, hematocrit determination, or newborn screening. Capillary tubes are significantly smaller in diameter compared to traditional venous blood collection tubes. They are usually made of plastic or glass and are cylindrical in shape. The dimensions vary, typically around 75-100 mm long and 0.5-1.0 mm in diameter. Like venous blood collection tubes, capillary tubes often come in different colors, each indicating the type of additive or anticoagulant in the tube. Common colors include red, lavender, green, and blue. These additives serve various purposes, such as preventing blood clotting, stabilizing analytes, or facilitating specific tests. BV Depending on the intended use, capillary tubes may contain different additives or anticoagulants. For example, tubes used for glucose testing often contain heparin to prevent clotting, while tubes for hematocrit determination may not contain additives. Capillary tubes are designed for micro-collection, meaning they can hold very small volumes of blood, typically ranging from 50 to 500 microliters. This makes them ideal for tests requiring only a small sample volume, such as blood glucose monitoring in diabetic patients. Capillary tubes may have various sealing mechanisms to prevent leakage or contamination of the blood sample. Some tubes come with caps that can be snapped or screwed on, while others have integrated closure J mechanisms. M D Centrifuge A centrifuge is a laboratory device used to separate components of a heterogeneous mixture based on their RM density, size, and shape through high-speed spinning. It operates on the principle of centrifugal force, which causes denser particles or substances to move outward and settle at the bottom of the centrifuge tube. In contrast, lighter components move toward the top. T 9 / 109 BV J Cuvette M A cuvette is a small, transparent vessel or container used in spectrophotometry, fluorometry, and other chemistry, biochemistry, and molecular biology analytical techniques. It is specifically designed to hold liquid samples for optical analysis, allowing the passage of light through the sample to measure its absorbance, fluorescence, or other optical properties. Cuvettes are commonly made of high-quality optical materials such as glass, quartz, or plastic (typically acrylic or polystyrene). The choice of material depends on the specific application, optical properties required, and D compatibility with the sample and solvent. Cuvettes come in various shapes and sizes, including rectangular, square, or cylindrical. The dimensions of the cuvette can vary, but they are typically small and have a volume capacity ranging from a few hundred microliters to several milliliters. The size and shape of the cuvette can affect the path length of light through the sample and the optical path geometry, which can impact the accuracy of measurements. The optical path length refers to the distance light travels through the sample in the cuvette. Some cuvettes have fixed path lengths, while others allow interchangeable inserts or adjustable path lengths to accommodate RM different experimental requirements. Cuvettes have transparent windows on opposite sides to allow light through the sample. These windows are typically polished to minimize light scattering and distortion. In UV-visible spectroscopy, cuvettes may have windows made of quartz or glass, which have good transparency in the ultraviolet and visible wavelength ranges. Cuvettes often feature a closure mechanism to seal the sample inside and prevent evaporation or contamination during analysis. Common closure mechanisms include snap-on lids, screw caps, or stoppers. Cuvettes should be compatible with the specific instrument or spectrophotometer used for analysis. They come in standard sizes and configurations to fit most spectrophotometer holders or cuvette compartments. Some cuvettes are designed for specific applications, such as fluorescence spectroscopy, microvolume analysis, or temperature-controlled experiments. These specialty cuvettes may have features such as reduced sample T volume requirements, optical coatings, or built-in temperature control systems. 10 / 109 Erlenmeyer Flask An Erlenmeyer flask, named after its inventor, the German chemist Emil Erlenmeyer, is a commonly used BV laboratory glassware vessel with a distinctive conical shape. It is widely used in chemistry, biology, and other scientific disciplines for various purposes, including mixing, heating, and storing liquids. The Erlenmeyer flask has a conical shape, flat bottom, and cylindrical neck. The conical body allows for efficient mixing and swirling of liquids, while the cylindrical neck facilitates pouring and minimizes the risk of spills. Many Erlenmeyer flasks feature graduated markings along the side, indicating volume measurements in milliliters (mL) or cubic centimeters (cc). These graduations allow for accurate measurement and dispensing of liquids. J Erlenmeyer flasks can be fitted with stoppers or closures to seal the contents and prevent contamination or evaporation. Rubber or silicone stoppers are commonly used and come in various sizes to securely fit different flask necks. Erlenmeyer flasks are designed to withstand moderate to high temperatures and are widely used for heating M liquids on a hot plate or in a water bath. However, caution should be exercised to avoid rapid temperature changes that could cause thermal stress and potential breakage. D RM T Glass Slide with Cover Slip A glass slide with a cover slip is a fundamental tool used in microscopy for preparing and observing biological, histological, and other types of specimens under a microscope. This combination comprises two components: a glass slide and a cover slip. 11 / 109 BV Gloves Gloves are protective garments designed to cover and protect the hands from various hazards, including chemicals, biological agents, physical abrasions, and contaminants. They are worn in multiple settings, including healthcare, laboratories, manufacturing, food handling, cleaning, and many others. Gloves come in different materials, styles, and sizes, each suited to specific applications and requirements. Natural rubber latex gloves provide excellent elasticity, comfort, and dexterity. They offer good protection against biological hazards but may cause allergic reactions in some individuals. J Nitrile gloves are synthetic and offer excellent resistance to chemicals, punctures, and abrasions. They are an alternative for individuals allergic to latex and are commonly used in healthcare and laboratory settings. Vinyl gloves are made from PVC (polyvinyl chloride) and protect against mild chemicals and biological hazards. They are often used in food handling and general cleaning tasks. M Neoprene gloves offer good resistance to chemicals, oils, and solvents. They are commonly used in laboratories and industrial settings where chemical protection is required. Butyl rubber gloves offer superior resistance to chemicals and gases, making them suitable for handling hazardous materials in industrial and chemical settings. Gloves come in various thicknesses, ranging from thin, disposable gloves (e.g., 4-5 mils) to thicker, heavy- duty gloves (e.g., 15-30 mils). Thicker gloves offer more excellent protection against punctures and abrasions but may sacrifice dexterity and tactile sensitivity. D Powdered gloves are coated with a fine powder, such as cornstarch or talcum, to make them easier to don and remove. However, the powder can contaminate surfaces and cause allergic reactions in some individuals. Powder-free gloves are free of this powder coating and are preferred in many applications, including healthcare. Some gloves have textured surfaces, such as micro-roughened or textured fingertips, to improve grip and handling of objects, especially in wet or oily conditions. Gloves come in various sizes, including small, medium, large, and extra-large, to accommodate different RM hand sizes. Proper sizing is essential to ensure a comfortable fit and adequate protection. Some gloves are ambidextrous, meaning they can be worn on either hand, while others are hand-specific, designed for the left or right hand. Hand-specific gloves often provide a better fit and comfort. T 12 / 109 Graduated Cylinder A graduated cylinder is a common laboratory glassware used for accurately measuring the volume of liquids. It features a cylindrical shape with a narrow vertical tube and graduated markings along its length. Graduated cylinders come in various sizes, ranging from small capacities suitable for precise measurements to larger capacities for bulk measurements. The most distinctive feature of a graduated cylinder is the graduated markings along its length, which indicate volume measurements. These graduations are calibrated in units such as milliliters (mL) or cubic centimeters (cc), and they allow for precise measurement of liquid volumes. Graduations may be marked at regular intervals (e.g., every 1 mL) or at varying intervals to accommodate different measurement ranges. When measuring the volume of a liquid in a graduated cylinder, it's important to read the volume at the bottom of the meniscus. The meniscus is the curved surface of the liquid caused by surface tension. To obtain an BV accurate measurement, the eye should be level with the liquid's surface, and the measurement should be taken at the lowest point of the meniscus. J M D RM Haemocytometer (Neubauer’s Counting Chamber) with a Cover Slip A haemocytometer, also known as a hemocytometer or counting chamber, is a specialized laboratory device used for manual cell counting. It consists of a thick glass slide with a rectangular indentation, which creates a small chamber. This chamber is etched with precise grids or ruled lines to facilitate the accurate counting of cells or other microscopic particles suspended in a liquid, typically a biological sample such as blood or cell culture. The central part of the haemocytometer slide features a shallow rectangular indentation, known as the T counting chamber or cell counting area. This chamber has a standard size and depth, allowing for consistent and accurate cell counting. The floor of the counting chamber is etched with a grid pattern or ruled lines, which divide the chamber into smaller squares or rectangles. These grids provide reference points for counting cells and determining cell density. The grids are typically engraved or etched into the glass, ensuring durability and resistance to wear over time. The depth of the counting chamber is critical for accurate cell counting. It is designed to create a uniform layer of liquid suspension over the grid pattern, allowing cells to settle evenly and facilitating clear visualization under a microscope. 13 / 109  Haemocytometers come in various sizes and configurations, with standard dimensions for the counting chamber and grids. The size of the grids and the depth of the chamber determine the volume of liquid sampled and the area used for cell counting. To prevent evaporation and maintain a uniform distribution of cells in the liquid sample, a cover slip is placed over the counting chamber. The cover slip is usually thin and transparent, made of glass or plastic. It also serves to flatten the liquid surface and minimize optical distortions during cell counting. To use a haemocytometer, a known volume of the liquid sample containing suspended cells is pipetted into the counting chamber. The sample is spread evenly across the chamber by capillary action, and the cover slip is carefully placed over the chamber. The slide is then placed under a microscope for visualization, and cells within the grid squares are counted manually using a counting method such as the "4x4" method or the "5x5" method. BV J M Hot Plate A hot plate is a laboratory heating device used to heat or maintain the temperature of liquid or solid samples in glassware or containers. It consists of a flat, heat-resistant surface, typically made of metal (such as aluminum or stainless steel), with an embedded heating element underneath. Hot plates are widely used in scientific research, education, and various industries for applications such as heating solutions, conducting chemical reactions, melting solids, and incubating samples. D Hot plates typically feature temperature control mechanisms that allow users to set and regulate the desired temperature of the heating surface. This can be achieved through analog dials or digital displays with temperature settings in degrees Celsius or Fahrenheit. Some hot plates also feature feedback control systems, such as PID (proportional-integral-derivative) controllers, for more precise temperature control. Some hot plates come equipped with built-in magnetic stirrers, allowing for simultaneous heating and stirring of liquid samples. These hot plate stirrers feature a rotating magnetic stir bar placed inside the glassware, which is driven by a magnetic field generated by a rotating magnet located beneath the heating surface. RM T 14 / 109 Incubation Chamber An incubation chamber, also known as an incubator, is a controlled environment used to provide optimal conditions for the growth, cultivation, and observation of biological specimens, such as microorganisms, cells, tissues, or embryos. It is an essential piece of equipment in laboratories, research facilities, and healthcare settings where precise temperature, humidity, and other environmental factors are critical for successful incubation and experimentation. An incubation chamber maintains a constant and precise temperature suitable for the growth and maintenance of the biological specimens being cultured. Temperature control systems may include electric heating elements, thermoelectric coolers, or Peltier devices, along with temperature sensors and feedback control mechanisms to maintain the set temperature accurately. Many biological specimens require specific humidity levels to thrive and grow optimally. Incubation BV chambers often feature humidity control systems, such as water reservoirs, humidifiers, or desiccants, to regulate humidity levels within the chamber. Humidity sensors and controllers ensure that the desired humidity setpoint is maintained consistently. Proper air circulation within the incubation chamber helps maintain uniform temperature and humidity throughout the chamber and prevents the formation of hot spots or condensation. Fans or blowers may be incorporated into the design of the chamber to facilitate air movement and ensure even distribution of heat and moisture. Incubation chambers are designed to minimize the risk of contamination by providing a clean and sterile J environment for biological cultures. Some chambers feature built-in sterilization systems, such as ultraviolet (UV) lamps or high-temperature autoclaving capabilities, to disinfect the interior surfaces and prevent the growth of contaminants. Incubation chambers are equipped with monitoring and control systems to regulate and maintain the environmental parameters within the chamber. This may include digital control panels or touch-screen interfaces for M setting and adjusting temperature, humidity, and other parameters, as well as built-in sensors for monitoring environmental conditions in real time. Incubation chambers come in a range of sizes and capacities to accommodate different volumes of samples and experimental setups. Benchtop models are suitable for small-scale experiments and limited laboratory space, while larger floor-standing units can accommodate larger quantities of samples and offer more features and flexibility. D RM T 15 / 109 Lancet Device A lancet device, also known as a lancet holder or lancing device, is a handheld medical device used for obtaining capillary blood samples for diagnostic testing, such as blood glucose monitoring or hemoglobin testing. It is commonly used by individuals with conditions like diabetes who need to monitor their blood sugar levels regularly. The lancet device provides a safe, controlled method for puncturing the skin and drawing a small drop of blood for analysis. BV J M Measuring Beaker A measuring beaker, also known simply as a beaker, is a common laboratory glassware used for measuring, mixing, and pouring liquids. It typically has a cylindrical shape with a flat bottom and a spout for easy pouring. Measuring beakers come in various sizes and are widely used in scientific research, education, and industrial applications for a wide range of liquid handling tasks. Many measuring beakers feature graduated markings along the side, indicating volume measurements in D milliliters (mL) or cubic centimeters (cc). These graduations allow for accurate measurement and dispensing of liquids. Graduations may be marked at regular intervals (e.g., every 10 mL) or at varying intervals to accommodate different measurement ranges. Measuring beakers come in various sizes, with capacities ranging from a few milliliters to several liters. The choice of size depends on the volume of liquid to be measured and the specific application. Measuring beakers are available in standard sizes such as 50 mL, 100 mL, 250 mL, 500 mL, 1 L, and so on. RM T 16 / 109 Measuring Pipette A measuring pipette, commonly referred to as a graduated pipette or volumetric pipette, is a precision laboratory instrument used for accurately measuring and transferring a specific volume of liquid. It is widely used in scientific research, education, and industrial laboratories for various liquid handling tasks, including titrations, dilutions, and preparation of solutions. Measuring pipettes are marked with graduated lines along their length, indicating volume measurements in milliliters (mL) or fractions of a milliliter. The graduations are calibrated to allow for accurate measurement of specific volumes, with each graduation representing a precise volume increment. The volume indicated by the graduations may vary depending on the capacity of the pipette, ranging from microliters to milliliters. Measuring pipettes are calibrated to meet specific accuracy and precision standards, ensuring reliable and reproducible volume measurements. Calibration certificates may be provided by manufacturers to certify the BV accuracy of the pipette and its conformity to international standards, such as ISO (International Organization for Standardization) or ASTM (American Society for Testing and Materials). To use a measuring pipette, the user first draws the liquid into the pipette by immersing the tapered tip into the liquid and creating a vacuum by mouth or using a mechanical pipetting aid. Once the desired volume of liquid is drawn into the pipette, the user dispenses it by carefully draining the liquid from the tapered tip into a receiving vessel, such as a test tube or flask. To ensure accurate measurement, the liquid level is adjusted to the calibration mark on the pipette, taking into account factors such as meniscus formation and parallax error. J M D RM T Microcentrifuge Tubes Microcentrifuge tubes, also known as microtubes or microfuge tubes, are small plastic tubes commonly used in laboratory settings for the storage, centrifugation, and manipulation of small volumes of liquids or samples. They are essential tools in molecular biology, biochemistry, microbiology, and other scientific disciplines for a wide range of applications, including DNA/RNA isolation, protein purification, PCR (polymerase chain reaction), and sample storage. 17 / 109  Microcentrifuge tubes come in various sizes and capacities, ranging from 0.2 mL to 2.0 mL, with 1.5 mL being the most common size. Tubes with smaller volumes are often used for applications requiring minimal sample volumes or for high-throughput experiments, while larger tubes are used for more extensive samples or dilutions. Many microcentrifuge tubes are marked with volume graduations along the side, indicating the volume of liquid contained within the tube. These graduations allow for quick and easy estimation of sample volumes without the need for additional measuring devices. Microcentrifuge tubes are typically equipped with a secure closure mechanism to prevent leakage and ensure sample integrity during centrifugation or storage. The most common closure types include snap caps, screw caps, or plug caps, which provide a tight seal and can be opened and closed easily with one hand. Microcentrifuge tubes are compatible with various laboratory equipment and instruments, including microcentrifuges, vortex mixers, thermal cyclers, and automated liquid handling systems. They are designed to fit BV securely into standard microcentrifuge rotor buckets and can withstand high-speed centrifugation without leaking or rupturing. J M D Micropipette A micropipette is a precision laboratory instrument used for accurately measuring and transferring small volumes of liquid. It is a fundamental tool in many scientific disciplines, including molecular biology, biochemistry, microbiology, and analytical chemistry, where precise liquid handling is crucial for experimental success. RM Micropipettes provide accurate and reproducible dispensing of liquids, making them indispensable in research, clinical diagnostics, and quality control processes. Micropipettes feature a volume adjustment dial or knob that allows users to set the desired volume to be aspirated or dispensed. The dial typically has a digital or analog display indicating the selected volume in microliters (µL) or milliliters (mL). A tip ejector button or lever is located on the top or side of the micropipette body, allowing users to easily attach and remove disposable pipette tips. Pressing the tip ejector expels the used tip after dispensing, enabling quick and hygienic tip changes between samples. Micropipettes are used in conjunction with disposable pipette tips, which are made of high-quality plastic and come in various sizes to accommodate different sample volumes. The pipette tip attaches securely to the end of the micropipette nozzle and forms a tight seal to prevent leakage and ensure accurate liquid transfer. T Micropipettes are available in different volume ranges, from microliters (µL) to milliliters (mL), depending on the specific application and user requirements. Common micropipette volumes include 0.1-10 µL, 0.5-20 µL, 2- 200 µL, 20-200 µL, 100-1000 µL, and 1000-5000 µL. Micropipettes require regular calibration to ensure accurate and reliable performance. Calibration involves verifying the accuracy and precision of the pipette's volume settings using calibrated reference standards. Calibration certificates may be provided by manufacturers to certify the accuracy of the pipette and its adherence to international standards. 18 / 109 BV J Microscope M A microscope is an optical instrument used for magnifying and observing small objects or details that are not visible to the naked eye. It plays a crucial role in scientific research, education, medicine, and various other fields by enabling scientists, researchers, and clinicians to examine microscopic structures, organisms, and materials in detail. Microscopes come in a variety of types and configurations, each designed for specific applications and magnification requirements. Compound light microscopes use an illumination system to illuminate the specimen being observed. This system typically consists of a light source, such as an LED bulb or halogen lamp, positioned beneath the stage. The D light passes through a condenser lens, which focuses and directs the light onto the specimen, providing uniform illumination for clear observation. Microscopes feature multiple lenses, including the objective lenses and the ocular or eyepiece lens, which work together to magnify the image of the specimen. The objective lenses are mounted on a rotating nosepiece and are available in various magnification powers, typically ranging from 4x to 100x or higher. The ocular lens further magnifies the image produced by the objective lens and is usually interchangeable to accommodate different RM magnification levels. Microscopes are equipped with a focus mechanism consisting of coarse and fine adjustment knobs or controls to bring the specimen into sharp focus. The coarse adjustment knob moves the stage vertically to roughly focus the image, while the fine adjustment knob allows for precise focusing and fine-tuning of the image clarity. Compound microscopes typically have a binocular viewing head with two eyepieces, allowing for comfortable and stereoscopic viewing of the specimen. The interpupillary distance, or the distance between the eyepieces, is adjustable to accommodate different users’ preferences. The magnification of a microscope is determined by multiplying the magnification power of the objective lens by that of the eyepiece lens. Different combinations of objective and eyepiece lenses provide varying levels of magnification, allowing users to observe specimens at different scales. The field of view refers to the area visible T through the microscope's eyepiece and varies depending on the magnification level and numerical aperture of the objective lens. Many modern microscopes are equipped with digital imaging systems, such as built-in cameras or digital eyepiece attachments, which allow users to capture images and videos of the observed specimens. These images can be displayed on a computer monitor or stored digitally for further analysis, documentation, and sharing. 19 / 109 BV J M Motorized Homogenizer A motorized homogenizer, also known as a tissue homogenizer or a mechanical disruptor, is a laboratory instrument used to disrupt and homogenize biological samples, tissues, or other materials by applying mechanical D force. It is widely used in molecular biology, biochemistry, microbiology, and various other scientific disciplines for sample preparation, cell lysis, and nucleic acid extraction. The homogenizing probe, also known as a generator, disperser, or rotor-stator assembly, is the working part of the homogenizer that comes into contact with the sample. It is usually made of durable materials such as stainless steel or titanium and may have various shapes and configurations depending on the application. Common designs include saw-toothed or serrated edges, beads, or blades arranged in a helical or radial pattern. These features are RM designed to efficiently disrupt and homogenize the sample by shearing, grinding, or tearing apart the cellular structures or particles. Motorized homogenizers are used with sample tubes or vessels that contain the biological samples or materials to be homogenized. The sample tubes may vary in size and material, depending on the sample volume and compatibility with the homogenization process. Common types of sample tubes include microcentrifuge tubes, Eppendorf tubes, and grinding vials made of materials such as glass, plastic, or stainless steel. Motorized homogenizers typically feature speed control mechanisms that allow users to adjust the rotational speed of the homogenizing probe. This allows for precise control over the homogenization process, enabling optimization of parameters such as shear force, disruption efficiency, and sample temperature. Speed control may be achieved through analog dials or digital displays with adjustable speed settings in revolutions per minute (RPM) or oscillations per minute (OPM). T Some motorized homogenizers are equipped with temperature control systems to maintain the sample at a desired temperature during homogenization. This is particularly important for sensitive samples or applications where temperature stability is critical to preserving sample integrity and preventing degradation. Temperature control features may include built-in cooling or heating elements, thermostatic control units, or external circulators for precise temperature regulation. 20 / 109 BV J M D Parafilm RM Parafilm is a versatile laboratory material commonly used for sealing and protecting various items, including laboratory containers, Petri dishes, and test tubes. It consists of a thin, flexible, and stretchable film made primarily of a blend of paraffin wax and low-density polyethylene. Parafilm is transparent, moisture-resistant, and impermeable to gases, making it ideal for creating airtight seals and barriers in laboratory environments. Parafilm is composed of a mixture of paraffin wax and low-density polyethylene (LDPE). This combination gives it a unique blend of properties, including flexibility, stretchability, and durability. The paraffin wax component provides a water-resistant and moisture-proof barrier, while the LDPE component adds strength and flexibility to the film. Parafilm is highly flexible and stretchable, allowing it to conform to various shapes and sizes of laboratory containers and surfaces. When stretched gently, Parafilm forms a tight seal around the object, preventing leaks and evaporation of liquids, gases, or volatile substances. T Parafilm is impermeable to moisture and water vapor, providing an effective barrier against the ingress of liquids and humidity. It is commonly used to seal petri dishes, culture plates, and other containers to maintain the sterility of agar-based media and prevent contamination from airborne microorganisms or moisture. Parafilm is also impermeable to gases, making it useful for creating airtight seals and barriers in gas- sensitive experiments or storage applications. It is commonly used to seal test tubes, vials, and other containers containing volatile chemicals, solvents, or gases to prevent evaporation or leakage. Parafilm is transparent, allowing users to easily observe the contents of sealed containers without removing the film. This transparency is particularly useful in laboratory settings where visual inspection of samples or cultures is required. 21 / 109  Parafilm is easy to handle and apply, requiring no special equipment or tools for sealing containers. It can be cut to size using scissors or a blade and applied by stretching it gently over the opening of the container. While Parafilm is primarily intended for single-use applications, it can be reused multiple times if handled carefully and cleaned between uses. Reusing Parafilm can help reduce waste and save costs in laboratory operations. Parafilm finds a wide range of applications in laboratory research, including sealing test tubes, vials, microplates, and flasks; wrapping and protecting glassware and equipment; creating barriers for electrophoresis gels; and sealing culture media plates and dishes in microbiology and cell culture experiments. BV J M Pasteur Pipette A Pasteur pipette, also known as a transfer pipette or plastic dropper, is a common laboratory tool used for transferring small volumes of liquids. It is named after the renowned French microbiologist Louis Pasteur, who developed the pipette for use in his experiments. Pasteur pipettes are widely used in scientific research, education, and clinical laboratories for various liquid handling tasks, including sample transfer, dilution, and mixing. Pasteur pipettes are available in various sizes with different volume capacities, typically ranging from 1 mL D to 10 mL. The choice of pipette size depends on the specific application and the volume of liquid to be transferred. To dispense the liquid from the Pasteur pipette, the tip is gently pressed against the wall of the receiving vessel, and the bulb is squeezed to expel the liquid drop by drop. The rate of dispensing can be controlled by varying the pressure applied to the bulb. Pasteur pipettes are typically disposable and intended for single-use applications to prevent contamination and ensure accurate and reproducible results. After use, the pipette is discarded to avoid the risk of cross- RM contamination between samples. T 22 / 109 Petri Dish A Petri dish, also known as a Petri plate or cell-culture dish, is a shallow, cylindrical, and transparent container with a lid, typically made of glass or plastic. Petri dishes are widely used in laboratory settings for culturing, observing, and studying microorganisms, cells, tissues, and other biological specimens. They are essential tools in microbiology, molecular biology, biochemistry, and various other scientific disciplines. Petri dishes come with a detachable lid that fits snugly over the top of the dish to create a sealed environment. The lid helps prevent contamination of the cultured specimens by airborne microorganisms and provides a controlled environment for cell growth and observation. Many Petri dish lids feature ventilation ribs or slots that allow for air exchange while minimizing the risk of contamination. These ventilation features provide adequate airflow to support the growth of aerobic microorganisms without allowing contaminants to enter the dish. BV Petri dishes are designed to be stackable, allowing multiple dishes to be stacked on top of one another for convenient storage and handling. Stackability helps save space in the laboratory and facilitates the organization and labeling of multiple cultures. In addition to standard Petri dishes used for general culturing purposes, specialized Petri dishes are available for specific applications. For example, compartmentalized Petri dishes are used for simultaneous culturing of multiple samples or testing different conditions within the same dish. Grid-marked Petri dishes are used for precise colony counting and measurement. J M D pH Meter A pH meter is a precision instrument used to measure the acidity or alkalinity (pH) of a liquid solution. It is an essential tool in various scientific disciplines, including chemistry, biology, environmental science, and food science, where accurate pH measurements are critical for research, analysis, quality control, and process monitoring. The heart of a pH meter is its electrode system, which consists of a glass pH electrode and a reference electrode. The glass pH electrode contains a special glass membrane that selectively interacts with hydrogen ions (H⁺) in the solution, generating a voltage proportional to the pH of the solution. The reference electrode provides a RM stable reference potential against which the pH electrode's potential is measured. The pH meter operates based on the principle of potentiometry, where the voltage generated by the glass pH electrode is measured relative to the reference electrode. The difference in voltage between the two electrodes is converted into a pH value using a calibration curve or algorithm. pH meters require regular calibration using standard pH buffer solutions with known pH values. Typically, two or more buffer solutions are used to calibrate the meter across a range of pH values. Calibration ensures the accuracy and reliability of pH measurements by compensating for electrode drift and variations in instrument performance. pH meters feature a digital display screen that shows the pH value of the solution being measured. The display may also show other parameters such as temperature, mV (millivolt) readings, and calibration status. The T meter may have control buttons or knobs for power on/off, mode selection, calibration, and temperature compensation. Some advanced pH meters also offer touchscreen interfaces for intuitive operation. pH measurements are temperature-sensitive, so pH meters often include automatic temperature compensation (ATC) functionality to correct temperature variations. ATC ensures that pH readings remain accurate and consistent across different temperatures by adjusting the measured pH value based on the solution's temperature. Proper maintenance of the pH electrode is essential for optimal performance and accuracy. This includes rinsing the electrode with distilled water before and after each use, storing the electrode in a storage solution or buffer solution when not in use, and periodic cleaning and calibration according to the manufacturer’s recommendations. 23 / 109  pH meters are used in a wide range of applications, including water quality analysis, environmental monitoring, food and beverage testing, pharmaceutical manufacturing, chemical synthesis, and biological research. pH measurements are critical for ensuring product quality, process control, and regulatory compliance in many industries. BV J Pipette Aspirator A pipette aspirator, also known simply as an aspirator, is a laboratory instrument used for transferring liquids by creating suction or vacuum pressure. It is commonly used in microbiology, molecular biology, and other scientific disciplines for various liquid handling tasks, such as removing supernatant from samples, aspirating M reagents, or transferring liquids between containers. Pipette aspirators are typically handheld devices that resemble large syringes. They are ergonomically designed to fit comfortably in the user's hand and feature a plunger or piston mechanism for creating suction. Pipette aspirators are often made of durable and chemical-resistant materials such as polypropylene or stainless steel. The choice of material depends on the specific application and compatibility with the liquids being aspirated. Pipette aspirators rely on manual operation to create suction or vacuum pressure, eliminating the need for D external power sources or pumps. The vacuum is generated by manually pulling or pushing the plunger to decrease the pressure inside the device. RM T 24 / 109 Polyethylene Bag A polyethylene bag, often simply referred to as a plastic bag, is a flexible container made from polyethylene, a type of polymer widely used in packaging and manufacturing. Polyethylene bags come in various shapes, sizes, and thicknesses and are used for a wide range of purposes, including storage, transportation, and protection of goods. Polyethylene bags may be open-ended or feature various closure mechanisms to seal the bag and protect its contents. Common closure options include zip-lock seals, heat seals, adhesive seals, drawstrings, and twist ties. Zip- lock seals, also known as zipper seals or resealable closures, allow the bag to be opened and closed repeatedly, providing convenient access to the contents while maintaining freshness and preventing spills. Polyethylene bags are available in different thicknesses, measured in mils (thousandths of an inch) or micrometers (microns). Thicker bags offer greater strength and puncture resistance, making them suitable for BV heavier or sharp-edged items, while thinner bags are more lightweight and economical. Polyethylene bags are transparent or translucent, allowing users to easily view the contents without opening the bag. This transparency is particularly useful for product identification, inventory management, and visual inspection of stored items. Polyethylene bags are versatile packaging solutions suitable for a wide range of applications across industries. They are commonly used for packaging and storing food items, pharmaceutical products, medical supplies, electronics, textiles, hardware, and industrial components. Polyethylene bags are also used for waste disposal, recycling, and environmental cleanup efforts, providing a convenient and hygienic means of collecting and J transporting trash, recyclables, and hazardous materials. M D RM Plastic Tray A plastic tray is a flat, shallow container made from plastic materials such as polypropylene (PP), polystyrene (PS), or polyethylene (PE). Plastic trays come in a variety of shapes, sizes, and designs, and they are used for a wide range of applications across different industries, including food service, catering, healthcare, manufacturing, and retail. Plastic trays have diverse applications across various industries and sectors. Some common uses of plastic trays include: Food Service and Catering T Serving trays for food and beverage presentation, cafeteria trays, food storage trays, and display trays for bakery or deli products. Healthcare Instrument trays for medical procedures, sterilization trays for surgical instruments, specimen trays for laboratory testing, and medication dispensing trays. Manufacturing and Assembly Parts trays for organizing and transporting components in manufacturing processes, work-in-progress trays for assembly lines, and storage trays for small tools or supplies. 25 / 109  Retail and Merchandising Display trays for showcasing products in stores, packaging trays for protecting and presenting goods, and sorting trays for inventory management. BV Reagent Bottle A reagent bottle is a type of laboratory glassware designed for storing and dispensing liquid reagents, chemicals, solvents, or other substances used in laboratory experiments, analyses, and procedures. Reagent bottles are essential tools in scientific research, education, healthcare, and industrial laboratories, providing a safe and convenient way to store, handle, and transport various types of liquids. Reagent bottles are available in various sizes and capacities to accommodate different volumes of liquids. J Common sizes range from small bottles with capacities of a few milliliters to larger bottles with capacities of several liters. The choice of bottle size depends on factors such as the quantity of reagent needed, storage space availability, and frequency of use. Many reagent bottles feature graduated markings or scales on the side, indicating the volume or capacity of M the bottle in milliliters (mL) or liters (L). These markings allow users to accurately measure and dispense the desired amount of liquid reagent. Reagent bottles may be equipped with various types of closure mechanisms to seal the bottle and prevent evaporation, contamination, or spills. Common closure options include: Ground Glass Stoppers Tapered glass stoppers fit snugly into the bottleneck to create an airtight seal. Ground D glass stoppers provide excellent chemical resistance and are suitable for long-term storage of reagents. Screw Caps Plastic or metal caps with threaded closures that screw onto the bottleneck to create a secure seal. Screw caps are convenient for quick opening and closing of the bottle and may feature liners or gaskets for added leak resistance. Pouring Rings Optional accessories that fit around the bottleneck to facilitate controlled pouring and RM minimize spills when dispensing liquids from the bottle. Reagent bottles may have writable or printable areas on the surface for labeling the contents, concentration, expiration date, or other relevant information. Labels help ensure proper identification, organization, and traceability of reagents in the laboratory. T 26 / 109 BV Refrigerated Microcentrifuge J A refrigerated microcentrifuge is a laboratory instrument used for the centrifugation of small volumes of biological samples at high speeds while maintaining a controlled temperature. It is a specialized type of microcentrifuge equipped with a refrigeration system to keep samples cool during centrifugation, making it suitable for applications requiring temperature-sensitive samples or enzymes. M A key feature of a refrigerated microcentrifuge is its built-in refrigeration system, which maintains the temperature of the centrifuge chamber at a desired level during operation. The refrigeration system typically includes a compressor, condenser, evaporator, and temperature control unit. The temperature control unit regulates the temperature of the centrifuge chamber based on user-set parameters, ensuring precise temperature control throughout the centrifugation process. Refrigerated microcentrifuges are designed to accommodate microcentrifuge tubes or PCR tubes with volumes typically ranging from 0.2 mL to 2.0 mL. Some models may also support larger tube sizes or specialized D adapters for centrifugation of different sample types. The centrifuge rotor may have interchangeable buckets, adapters, or inserts to accommodate various tube sizes and configurations. Refrigerated microcentrifuges are used in a wide range of applications in molecular biology, biochemistry, cell biology, and clinical diagnostics. Common applications include DNA/RNA isolation, protein purification, cell fractionation, enzyme assays, and PCR amplification. The ability to maintain samples at low temperatures during centrifugation is particularly beneficial for applications involving heat-sensitive enzymes, proteins, or nucleic acids. RM T 27 / 109 BV J M RNase-Free Glass Bottles RNase-free glass bottles are specialized containers designed to prevent contamination of solutions with ribonucleases (RNases), enzymes that degrade RNA molecules. These bottles are essential in molecular biology, biochemistry, and biotechnology laboratories where RNA samples are handled, stored, and transported. The surfaces of RNase-free glass bottles undergo specialized treatments to render them free from RNase contamination. This typically involves rigorous cleaning, sterilization, and validation processes to eliminate RNases and other contaminants. Common methods for ensuring RNase-free surfaces include autoclaving, gamma D irradiation, treatment with RNase inhibitors, and washing with RNase-free reagents and detergents. RNase-free glass bottles are typically equipped with screw caps or stoppers made of chemically resistant materials such as polypropylene or PTFE (polytetrafluoroethylene). Screw caps may feature an elastomeric liner or O-ring to create a tight seal and prevent leakage or evaporation of the solution. Some caps may also have a tamper- evident or color-coded design for easy identification. RNase-free glass bottles are sterilized to eliminate microbial contaminants that could degrade RNA RM samples. Sterilization methods may include autoclaving, gamma irradiation, or ethylene oxide gas sterilization. The sterility of the bottles is verified through microbiological testing and validation procedures to ensure compliance with quality standards and regulatory requirements. RNase-free glass bottles are available in various sizes and capacities to accommodate different volumes of solutions. Common capacities range from a few milliliters to several liters. The bottles may have a cylindrical or square shape, with wide mouths for easy filling, pouring, and cleaning. Some bottles may also feature graduations or volume markings for accurate measurement of liquid volumes. RNase-free glass bottles may include writable or printable areas on the surface for labeling the contents, concentration, date of preparation, and other relevant information. Labels help ensure proper identification, organization, and traceability of samples in the laboratory. T 28 / 109 BV J Rocker Shaker for Laboratory A rocker shaker is a laboratory instrument used for agitation and mixing of samples in containers such as bottles, flasks, and tubes. It provides gentle and uniform rocking motion to facilitate the mixing, incubation, and M culturing of biological samples, cell suspensions, and solutions. Digital rocker shakers are commonly used in molecular biology, microbiology, cell culture, and biochemical research laboratories for various applications, including hybridization, staining, washing, gel electrophoresis, and protein blotting. Rocker shakers generate a rocking motion by oscillating the platform back and forth around a horizontal axis. The angle and speed of the rocking motion can be adjusted to suit the specific requirements of the experiment or application. The rocking motion provides gentle agitation and mixing of samples while minimizing the formation D of foam or bubbles, making it suitable for delicate biological samples and cell cultures. Rocker shakers offer variable speed control to adjust the rocking speed according to the viscosity of the samples and the desired mixing intensity. The speed range may vary between models, typically ranging from a few RPM (rotations per minute) to several hundred RPM. Precise speed control ensures uniform mixing and agitation of samples while minimizing shear forces that could damage sensitive cells or biomolecules. Many rocker shakers are equipped with a timer function that allows users to set the duration of agitation or RM mixing cycles. The timer can be programmed to run for a specified period or to operate continuously until manually stopped. The timer function enhances the reproducibility of experiments and allows researchers to perform other tasks while the samples are being agitated. Digital rocker shakers are compatible with a wide range of sample containers commonly used in laboratory research, including microplates, culture flasks, bottles, tubes, and trays. They may include interchangeable platforms or adapters to accommodate different container sizes and types. T 29 / 109 BV Rubber Stopper A rubber stopper, also known as a rubber bung or cork stopper, is a cylindrical plug made from rubber or synthetic elastomers that is used to seal the openings of glassware or containers. Rubber stoppers are commonly J used in laboratories, industrial settings, and household applications for sealing vessels containing liquids, gases, or powders. Rubber stoppers come in various sizes and shapes to fit different types of glassware and containers. Common shapes include cylindrical, tapered, or conical stoppers. Rubber stoppers are available in standardized sizes designated by numbers or letters, such as No. 0, No. 1, No. 2, etc., or by specific dimensions measured in M millimeters (e.g., 10 mm, 14 mm, 20 mm). Rubber stoppers are resistant to a wide range of chemicals, solvents, acids, and bases commonly encountered in laboratory applications. However, the chemical compatibility of the stopper material should be considered when selecting a stopper for a specific application. Silicone rubber stoppers, in particular, offer excellent chemical resistance and are suitable for use with most laboratory reagents and solutions. Rubber stoppers are used in a wide range of laboratory applications for sealing glassware, flasks, bottles, D test tubes, and other containers. They are commonly used in chemistry, biology, microbiology, pharmaceuticals, and food science laboratories. Rubber stoppers are used to seal containers during storage, transportation, heating, cooling, mixing, and reaction processes. They prevent contamination, evaporation, spillage, and leakage of liquids, gases, or powders contained within the vessel. RM Rubber Sucking Tube T The rubber-sucking tube is made of durable and flexible rubber or synthetic elastomer, ensuring optimal suction and precise control during sample aspiration and dispensing. The material is chosen for its resistance to chemical degradation, compatibility with blood samples, and ease of cleaning and sterilization. The rubber-sucking tube is designed to fit securely onto the end of a WBC pipette, forming a tight seal to prevent leakage or contamination of the sample. The rubber-sucking tube is compatible with various models and brands of WBC/RBC pipettes used in hematology laboratories and medical facilities. It is designed to work seamlessly with automated hematology analyzers, manual cell counters, and other instruments used for white blood cell counting and analysis. 30 / 109 BV Slide Holder A slide holder is a device used to securely hold microscope slides in place during examination, staining, imaging, or storage. It is an essential accessory in microscopy and histology laboratories, allowing for convenient J handling and organization of slides while minimizing the risk of damage or contamination. M D Spectrophotometer A spectrophotometer is a scientific instrument used to measure the intensity of light at different wavelengths in the electromagnetic spectrum. It is a versatile tool employed in various fields such as chemistry, biochemistry, physics, environmental science, and pharmaceuticals. Spectrophotometers are utilized for quantitative RM analysis, colorimetry, and qualitative analysis of substances based on their absorbance or transmittance of light. Spectrophotometers consist of an optical system that directs light through a sample and measures its absorption or transmission characteristics. The basic components of the optical system include a light source, a monochromator or wavelength selector, a sample compartment, and a detector. The light source may be a tungsten lamp for visible and near-infrared measurements or a deuterium lamp for ultraviolet measurements. Some advanced models may include xenon or LED light sources for broader spectral coverage and enhanced stability. The monochromator selects specific wavelengths of light from the source and directs them onto the sample. The sample compartment holds the sample to be analyzed, typically in a cuvette or test tube. The detector measures the intensity of light that passes through the sample and converts it into an electrical signal. Spectrophotometers allow users to select specific wavelengths of light for analysis. This is achieved by T adjusting the wavelength selector, which may be a prism, grating, or interference filter. Users can choose single wavelengths for monochromatic analysis or scan across a range of wavelengths to obtain a spectrum of absorbance or transmittance values. Spectrophotometers offer various measurement modes, including absorbance, transmittance, and concentration. Absorbance mode measures the amount of light absorbed by the sample at a specific wavelength and is commonly used for quantitative analysis based on Beer-Lambert’s law. Transmittance mode measures the fraction of incident light transmitted through the sample and is useful for qualitative analysis and colorimetric assays. Concentration mode calculates the concentration of a substance in solution based on its absorbance and a calibration curve of known concentrations. 31 / 109  Spectrophotometers often feature built-in software for data acquisition, processing, and analysis. The software allows users to store and manage spectral data, perform mathematical calculations, and generate graphs or reports. Some spectrophotometers may include advanced data analysis features such as spectral fitting, kinetics analysis, and multicomponent analysis. Spectrophotometers typically have a user-friendly interface with a digital display, keypad, or touchscreen for controlling instrument settings and viewing measurement results. Users can input parameters such as wavelength, measurement mode, and sample identification using the interface. Spectrophotometers accommodate various types of samples, including liquids, solids, and gases. Liquid samples are usually placed in cuvettes made of quartz or optical glass, while solid samples may require specialized accessories such as integrating spheres or diffuse reflectance attachments. Some spectrophotometers offer options for microvolume measurements using small-volume cuvettes or microplates. BV Spectrophotometers require periodic calibration and quality control to ensure accurate and reliable measurements. Calibration is performed using standard reference materials or calibration standards with known absorbance or transmittance values. Quality control measures may include regular performance checks, instrument validation, and compliance with regulatory standards such as Good Laboratory Practice (GLP) or Good Manufacturing Practice (GMP). J M D RM Staining Tray A staining tray is a laboratory apparatus used for staining biological specimens on microscope slides. It provides a convenient and organized way to perform staining procedures by holding multiple slides in a flat, shallow container filled with staining solutions. Staining trays are commonly used in histology, microbiology, cytology, and other biological sciences for preparing samples for microscopic examination. Staining trays are compatible with a wide range of staining reagents, fixatives, dyes, and solvents commonly used in histological and microbiological staining procedures. Plastic staining trays are resistant to most chemicals used in laboratory applications and are suitable for both aqueous and organic solvent-based staining solutions. Glass staining trays offer superior chemical resistance and are recommended for staining procedures T involving harsh chemicals or organic solvents. Staining trays should be cleaned thoroughly after each use to remove residual staining reagents, contaminants, or biological material. Plastic staining trays can be cleaned using soap and water, followed by rinsing with distilled water or ethanol. Glass staining trays can be cleaned using detergents, solvents, or acid-based cleaners, followed by rinsing with distilled water. 32 / 109 Sterile or RNase-Treated Pipette Tips BV Sterile or RNase-treated pipette tips are specialized disposable tips used in molecular biology, biochemistry, and cell biology laboratories for precise and contamination-free transfer of liquids, particularly when handling sensitive samples such as RNA. These tips are essential for preventing contamination with ribonucleases (RNases), enzymes that can degrade RNA molecules and compromise experimental results. Sterile pipette tips undergo sterilization using methods such as gamma irradiation, autoclaving, or ethylene oxide gas treatment to eliminate microbial contaminants. Sterilization ensures that the tips are free from bacteria, fungi, and other microorganisms that could compromise experimental results or introduce artifacts. RNase-treated pipette tips are treated with RNase inhibitors or subjected to specialized cleaning processes to remove RNase contamination. RNase treatment is essential for preventing the degradation of RNA samples J during pipetting and handling, ensuring the integrity of RNA molecules for downstream applications such as RT- PCR, RNA sequencing, and gene expression analysis. Sterile or RNase-treated pipette tips are compatible with a wide range of liquid handling applications, including sample preparation, PCR, qPCR, DNA sequencing, and cell culture. They can be used with various types M of reagents, buffers, enzymes, and biological samples without the risk of contamination or sample degradation. Sterile or RNase-treated pipette tips are disposable and intended for single-use only to prevent cross- contamination between samples and minimize the risk of carryover. After each use, the tips should be discarded properly according to laboratory waste disposal guidelines. D RM Stirring Glass Rod A stirring glass rod, also known as a stirring rod or stir rod, is a laboratory tool used for mixing, stirring, T and agitating liquids or solutions in laboratory glassware. It is commonly used in chemistry, biology, and other scientific disciplines for various applications such as dissolving solids, homogenizing mixtures, and facilitating chemical reactions. Stirring glass rods have a smooth surface finish to minimize friction and ensure smooth stirring motion without scratching or damaging the inner surface of glassware. The smooth surface also facilitates easy cleaning and sterilization of the stirring rod between uses. 33 / 109  Borosilicate glass stirring rods are compatible with a wide range of chemicals, solvents, acids, and bases commonly used in laboratory applications. They are resistant to most acids, alkalis, and organic solvents, making them suitable for stirring corrosive or reactive substances. Borosilicate glass stirring rods are highly heat-resistant and can withstand elevated temperatures without deformation or damage. They are often used for stirring solutions during heating or cooling processes, such as refluxing, distillation, or crystallization. Stirring glass rods are easy to handle and use. To stir a solution, the rod is inserted into the container and rotated manually or with the assistance of a stirring device. Care should be taken to ensure that the stirring rod does not come into contact with the sides or bottom of the glassware to avoid splashing or splintering. Stirring glass rods should be cleaned thoroughly after each use to remove any residue or contamination. They can be cleaned using soap and water, followed by rinsing with distilled water or solvent and drying with a lint- BV free cloth or air. It is important to inspect stirring glass rods regularly for any signs of damage, such as chips, cracks, or scratches, and replace them if necessary to prevent contamination or injury. J M D RM Syringe with Needles A syringe with needles is a medical device used for administering medications, withdrawing fluids, or performing various medical procedures. It consists of a cylindrical barrel, a plunger, and a needle attached to the end of the barrel. Syringes with needles are commonly used in healthcare settings for injections, vaccinations, blood draws, and other medical interventions. Syringes with needles are available in various sizes, ranging from small-volume insulin syringes (e.g., 0.3 mL to 1 mL) to larger-volume syringes (e.g., 3 mL to 60 mL) for different medical applications. Needle lengths and gauges vary depending on the intended route of administration and the type of tissue being penetrated (e.g., intramuscular, subcutaneous, intravenous). T Syringes with needles are typically sterile, single-use devices designed for one-time use to prevent contamination and reduce the risk of infections. They are individually packaged in sealed, sterile packaging to maintain sterility until they are ready to be used. Syringes with needles may have a Luer lock or Luer slip connection between the needle and the barrel. Luer lock syringes have a threaded tip on the barrel and a matching threaded hub on the needle, providing a secure connection that prevents accidental detachment during use. Luer slip syringes have a smooth, tapered tip on the barrel that fits snugly into the hub of the needle. The needle is pushed onto the barrel and held in place by friction. Syringes with needles are disposable medical devices intended for single use only. After use, they should be properly disposed of in designated sharps containers to prevent injuries and minimize the risk of contamination. 34 / 109  Syringes with needles are used for various medical procedures, including injections (e.g., vaccines, medications), blood draws, intravenous infusions, and aspiration of fluids from body cavities or wounds. BV J M Test Tube Cap A test tube cap, also known as a test tube stopper or test tube lid, is a small cylindrical device designed to seal the open end of a test tube. It is commonly used in laboratories to prevent the contents of the test tube from spilling or evaporating during storage, transportation, or experimental procedures. Test tube caps come in various materials, sizes, and designs to accommodate different types of test tubes and laboratory applications. D Test tube caps are typically made of flexible and chemically resistant materials such as rubber, silicone, polyethylene, or polypropylene. Rubber stoppers are common for