Laboratory Procedures and Sterilization

• The following are study notes for a laboratory assistant exam, focusing on specific knowledge regarding laboratory procedures, equipment, and safety.

Handling and Sterilization of Materials

• Reusable material in contact with high-risk biological samples must be sterilized in an autoclave.
• Metal tongs should be used to hold glassware when removing it from heat.
• Material intended to contain biological samples is considered to be of high risk.
• Material for collecting samples for microbiological analysis must be sterile.
• Reusable laboratory material with lipophilic residues should be cleaned with organic solvents.
• For microscopic particle counting, a counting chamber is required.
• Petri dishes are used for preserving samples.
• Sample incubation should be done in an incubator, not a refrigerator or autoclave.
• Materials used for taking microbiological samples must be sterilized beforehand.

Microscopy

• Microscopic observation of "fresh" samples should be performed with unstained samples.
• The optical part of microscopes consists of two converging lenses.
• Auramine is used in fluorescence microscopy.
• The microscope stage (platina) is used to hold the preparation being observed.

Culture Media

• Dehydrated culture media should be stored at a temperature between +15 and +26 °C.
• Distilled water with a near-neutral pH should be used in the preparation of culture media.
• The clarity of culture media is a physicochemical parameter.
• Culture media are mixtures of substances used for the growth and multiplication of bacteria.

Laboratory Procedures and Responsibilities

• Sample preparation in the laboratory should be performed by a laboratory assistant.
• Cleaning and maintaining laboratory equipment is one of the specific functions of a laboratory assistant.
• Preparing reagents and culture media are among the duties of a lab assistant.

Safety Practices

• A lab coat should always be worn when handling biological samples during the workday.
• Manipulation of microbiology samples should be carried out in laminar flow cabinets.
• Used, sharp disposable materials should be discarded in designated sharps containers.
• Flammable reagents must be handled in fume hoods.
• Radioactive isotopes produce gamma rays.

Sterilization and Disinfection

• Ethylene oxide is a high-level germicide.
• Sterilization is a procedure used to eliminate microorganisms, including resistant forms like spores.
• Aldehydes and ethylene oxide are chemical agents used as disinfectants and/or sterilizers.
• The Pasteur oven uses dry heat for sterilization.

Study notes on laboratory procedures for handling and sterilizing materials, microscopy, and necessary equipment. Focus on sterilization methods, microscopy techniques, and safe handling of biological samples. Includes best practices for cleaning and maintaining lab equipment.