Biotechniques BMS 34010A: Immunoassays Quiz

A mixture of antibodies that recognize many different parts of an antigen.

The clumping together of antigens and antibodies.

An immunoassay that uses an enzyme to produce a measurable signal.

A type of ELISA where both the capture and detection antibodies bind to the antigen in a sandwich fashion.

A microscopy technique to locate proteins or other molecules in tissue samples.

A microscopy technique that uses antibodies conjugated to fluorescent markers to visualize specific structures in specimens. The specimens are illuminated with ultraviolet light.

A technique used to identify proteins in a sample. It involves separating proteins by electrophoresis, transferring them to a membrane, and then using antibodies to detect specific proteins.

A process used in Western blotting to separate proteins based on their size and charge. Proteins are placed in a gel and an electric current is applied, causing the proteins to migrate.

A technique used to analyze cells individually as they flow in a fluid suspension. It uses lasers to measure cell properties such as size, shape, and the expression of specific molecules.

A specialized type of flow cytometry that allows the sorting of cells into separate containers based on their fluorescent and light scattering characteristics.

In Western blotting, a system where a single antibody directly binds to the target protein on the membrane. This antibody is conjugated to an enzyme that produces a detectable signal.

In Western blotting, a system where a primary antibody binds to the target protein, and a secondary antibody labeled with an enzyme binds to the primary antibody. This provides an amplified signal.

The membrane is treated with a protein-blocking solution to prevent non-specific binding of antibody to the membrane itself. This ensures that the antibody only binds to the target protein.

Indirect methods are often used because they are more cost-effective. The secondary antibody can be used to detect multiple primary antibodies, reducing the number of different antibodies needed.

The vibrating mechanism causes the stream of cells to break into individual droplets. This ensures that each droplet contains a single cell for accurate analysis.

The biological role a protein plays in a cell or organism. This can include things like catalysis, transport, structural support, and more.

Methods used to isolate and purify specific proteins from complex mixtures, often starting from cells or tissues.

A technique that uses high concentrations of ammonium sulfate to decrease protein solubility, causing them to precipitate out of the solution.

Separates proteins based on size by using a semi-permeable membrane which allows smaller molecules (salts) to pass through, but not larger proteins.

Method used to separate proteins based on their size and charge. Proteins are moved through a gel matrix by an electric current, smaller proteins move faster.

A technique that separates proteins based primarily on their mass. Proteins are denatured and given a uniform negative charge using SDS (sodium dodecyl sulfate).

An electrophoresis technique that separates proteins based on their mass-to-charge ratio. Proteins are not denatured, so their native structures are preserved.

A method to determine the total protein concentration in a solution. It involves reacting protein with a copper solution and Folin reagent to produce a blue color, which can be measured using spectrophotometry.

A technique used to measure how much light a substance absorbs at specific wavelengths.

An instrument that measures the amount of light absorbed by a substance.

A chemical test used to detect the presence of peptide bonds in a solution. This is an indicator of the presence of proteins.

1. Switch On the device. 2. Blank measurement. 3. Sample measurement. 4. Clean the device. 5. Switch OFF the device.

SDS disrupts the non-covalent bonds (like hydrogen bonds and hydrophobic interactions) that maintain a protein's tertiary and quaternary structure. This unfolds the protein into a linear chain.

Protein purification aims to isolate a specific protein of interest from a complex mixture of molecules. This is often necessary for research, therapeutic, and diagnostic purposes.

Knowing the protein concentration is essential for many experiments and applications. For example, it allows for accurate calculations for enzyme activity assays, protein-protein interactions, and antibody-antigen binding.

The process of separating and isolating a specific protein from a mixture, often starting from cells or tissues.

An instrument used in spectrophotometry that consists of a spectrometer to produce light of a specific wavelength and a photometer to detect the amount of absorbed light.

Atoms of the same element with different numbers of neutrons, resulting in different atomic masses.

The ratio of an ion's mass to its charge, used in mass spectrometry to identify and quantify molecules.

Higher charge results in a lower m/z value for the same mass. For example, a 2+ ion will have half the m/z value of a 1+ ion with the same mass.

The ability of a mass spectrometer to distinguish between molecules with very similar masses.

Mass spectrometry has wide applications, including environmental monitoring, drug analysis, protein identification, and geochemistry.

A device that measures the mass-to-charge ratio of ions, providing information about the composition and structure of molecules.

The process of converting neutral atoms or molecules into charged ions by removing or adding electrons.

The heart of a mass spectrometer, separating ions based on their mass-to-charge ratio using a magnetic field.

The ratio of an ion's mass to its electric charge, a key value for identifying and quantifying molecules in a mass spectrometer.

A component of a mass spectrometer that measures the number of ions reaching it, providing information about the abundance of each ion.

The process of verifying the accuracy of a mass spectrometer by comparing its measurements to known standards.

A simplified visual representation of mass spectrometer data, showing the relative abundance of different ions as vertical bars.

Multiple peaks in a mass spectrum arising from the presence of different isotopes of the same element in a molecule.

A device that maintains a low pressure inside the mass spectrometer, preventing collisions between ions and air molecules.

Analyzing the peaks in a mass spectrum to determine the composition and structure of the analyzed molecules.

A biochemical test that detects or measures the amount of a molecule using antibodies or antigens.

A substance that triggers an immune response and binds to antibodies.

Proteins that bind to specific antigens and are produced by your immune system.

Small molecules that can't induce an immune response alone but can when attached to a larger molecule (carrier).

Substances that boost the immune response to an antigen.

A visual representation of the separation of components in a sample, typically shown as peaks on a graph.

The time it takes for a specific component to travel through the chromatography column and reach the detector.

A type of chromatography where the stationary phase is spread on a flat surface like a sheet or plate.

A type of chromatography where the stationary phase is packed inside a vertical column.

The solvent that carries the sample through the chromatography system.

Protein purification aims to isolate a specific protein of interest from a complex mixture of molecules. This is crucial for studying its structure and function, increasing its stability, and for large-scale production.

Protein purification techniques exploit the differences in protein properties like size, charge, solubility, and affinity for specific molecules. Common methods include ammonium sulfate precipitation, dialysis, and gel electrophoresis.

High concentrations of ammonium sulfate decrease the solubility of proteins, causing them to precipitate (fall out of solution). Different proteins precipitate at different salt concentrations, allowing for separation.

Dialysis uses a semi-permeable membrane to separate proteins from smaller molecules like salts based on size. Larger proteins cannot pass through the membrane, while smaller molecules diffuse out.

A technique for separating proteins based on their size and charge. Proteins are loaded into a gel matrix and subjected to an electric current, causing them to migrate through the gel. Smaller proteins move faster.

An immunoassay is a biochemical test used to detect or measure the amount of a molecule in a sample, leveraging the highly specific interaction between antibodies and antigens.

Antibodies are Y-shaped proteins produced by the immune system that bind to specific antigens. They play a crucial role in recognizing and neutralizing harmful substances.

Antigens are molecules that can trigger an immune response. They are recognized by antibodies and can be proteins, carbohydrates, or lipids.

Affinity refers to the strength of a single antibody-antigen binding event. Avidity represents the overall strength of the interaction involving all binding sites on the antibody.

Haptens are small molecules that can't trigger an immune response on their own, but can do so when coupled to a larger carrier molecule.

A Y-shaped protein that binds to a specific antigen. Different antibodies have different binding sites and functions.

A substance that triggers an immune response and binds to antibodies.

An antibody's ability to bind only to its specific antigen, ignoring others.

The strength of the interaction between a single antibody and its specific antigen.

An immunoassay that uses an enzyme to produce a measurable signal (like a color change). This is used to detect the presence or quantity of an antigen.

A type of ELISA where the antibody that binds the antigen is directly linked to an enzyme. This is a simpler setup.

The immobile phase in chromatography, often a solid or gel, which interacts with the components of the mixture to be separated.

Different types of chromatography, like paper chromatography, column chromatography, HPLC, ion-exchange, affinity, and gas chromatography, are used based on the specific properties of the components to be separated.

Cell culture media provides the essential nutrients, salts, pH indicators, buffers, and supplements for cell growth. These include amino acids, glucose, vitamins, magnesium, sodium, potassium, calcium, phosphate, and chloride ions, as well as antibiotics, antimycotics, and growth factors.

Adherent cells require attachment to a solid surface for growth, forming monolayers, while suspension cells grow freely in the culture medium without needing to attach.

These are single cell types that have gained the ability for infinite growth, often due to genetic mutations or viral vectors.

The initial phase of cell growth where cellular activity increases, but there's no visible increase in cell number.

A common supplement in cell culture media that contains growth factors, hormones, and enhances cell attachment, but can also introduce contaminants.

The process of isolating a specific protein from a complex mixture of molecules. This is essential for research, to study its structure and function, for therapeutic purposes (like making medicines), and to create large quantities for specific applications.

A mass spectrometer consists of three main components: an ionization source, a mass analyzer, and an ion detector.

1. Ionization: Molecules are converted into ions. 2. Acceleration: The ions are accelerated. 3. Deflection: The ions are deflected in a magnetic field based on their m/z ratio. 4. Detection: The deflected ions are detected.

Mass spectrometry has many applications, including identifying unknown compounds, quantifying known compounds, and determining the structure and chemical properties of molecules.

In mass spectrometry, molecules are bombarded with high-energy electrons, causing them to ionize and fragment. The ions are then separated based on their mass-to-charge ratio (m/z).

The mass-to-charge ratio (m/z) is a key value in mass spectrometry, as it allows us to identify different molecules based on their unique m/z values.

There are different types of mass analyzers, including quadrupole, time-of-flight, and magnetic sector analyzers.

Mass spectrometry data is interpreted by analyzing the peaks in the spectrum, which correspond to different ions with their specific m/z values.

Analyzing the peaks in a mass spectrum to determine the composition and structure of the analyzed molecules.

Molecules with the same molecular formula (same number of atoms) but different arrangements.

Using mass spectrometry to analyze contaminants in soil, water, and air.

Mass spectrometry identifies drugs and their breakdown products in blood or urine.

Using mass spectrometry to determine the age of rocks and analyze the composition of soil, rocks, and oils.

A laboratory technique that uses enzymes to produce a measurable signal, often a color change, to detect the presence or amount of an antigen.

A type of ELISA where both the capture and detection antibodies bind to the antigen, creating a sandwich, allowing for more accurate measurement.

A fluorescent dye commonly used to label antibodies in immunoassays, enabling visualization under a microscope.

A very sensitive immunoassay technique that uses radioisotopes to label antibodies, allowing for detection of extremely small quantities of antigens.

An antibody is a Y-shaped protein made of four polypeptide chains (two heavy and two light chains) linked by disulfide bonds. Each chain has regions called variable and constant domains. The antibody's structure has two main functional parts: the Fab region, which binds to the antigen, and the Fc region, which interacts with other immune cells.

Antibodies have unique properties that make them effective at recognizing and targeting specific antigens. Specificity means each antibody recognizes one unique epitope (part of an antigen). Affinity describes the strength of the bond between an antibody and its antigen. Avidity refers to the overall strength of the antibody-antigen interaction, considering all binding sites.

Immunoassays are tests using antibodies to measure the presence or quantity of a molecule (antigen) in a sample. They rely on the very specific interaction between antibodies and their targets, like a lock and key.

There are five main types of antibodies in the human body: IgA, IgD, IgE, IgG, and IgM. Each has its own unique structure and function within the immune system.