Labeled Immunoassay

Question 1

Designed for antigens and antibodies that may be small in size or present in very low concentrations

Answer 1

Labeled Immunoassays

Question 2

is labeled by attaching a particle or molecule that will better detect lower concentration of antigen-antibody binding

Answer 2

Binding agent

Question 3

Examples of analytes determined using labeled immunoassays?

Answer 3

• Bacterial antigens
• Hormones
• Drugs
• Tumor markers
• Specific immunoglobulins
• Other proteins

Question 4

Types of Labels?

Answer 4

• Radionuclides
• Enzymes
• Fluorochromes
• Luminescent

Question 5

atoms with unstable nuclei that spontaneously emit radiation?

Answer 5

Radionuclides

Question 6

Emits beta particles or positron?

Answer 6

Beta radiation

Question 7

beta particles are?

Answer 7

Negatively charged

Question 8

positrons are?

Answer 8

Positively charged

Question 9

most common radionuclide for diagnosis and research in cellular immunology?

Answer 9

Tritium (3H)

Question 10

is tritium beta or gamma?

Answer 10

Beta

Question 11

Electromagnetic radiation with very short wavelength from an unstable nuclei

Answer 11

Gamma radiation

Question 12

most common in the clinical lab due to its longer half-life and appropriate energy level?

Answer 12

125I

Question 13

releases energy from decay of nuclei as it becomes more stable

Answer 13

Gamma radiation

Question 14

Detected using a crystal scintillation counter

Answer 14

Gamma radiation

Question 15

crystal scintillation counter aka?

Answer 15

Gamma counter

Question 16

Originally used to determine insulin-anti-insulin complexes in diabetic patients and is useful in measuring analytes occurring at trace concentrations

Answer 16

Radioimmunoassay

Question 17

who developed RIA?

Answer 17

Yalow and Berson

Question 18

disadvantages of RIA

Answer 18

health hazard and disposal problems

Question 19

react with suitable substrates to produce breakdown products that are either chromogenic, fluorogenic, or luminescent and developed as alternatives to RIAs

Answer 19

Enzyme Immunoassay

Question 20

Commonly used enzyme labels

Answer 20

• Horseradish peroxidase
• Alkaline phosphatase
• B-D-galactosidase

Question 21

Uses fluorochromes or fluorophores

Answer 21

Fluorescent labels

Question 22

Common fluorescent compounds used

Answer 22

Fluorescein and Rhodamine

Question 23

use labels that emit light as the result of electrical or chemical (oxidation) reaction?

Answer 23

Chemiluminescence

Question 24

Types of luminescent labels?

Answer 24

• Luminol
• Acridinium esters
• Ruthenium derivatives
• Nitrophenyl oxalates

Question 25

uses electrochemical compounds that generate light when redox reaction occurs?

Answer 25

Electrochemiluminescence immunoassay

Question 26

Labeled antigen competes with unlabeled antigen for a limited number of antibody-binding sites

Answer 26

Competitive Immunoassay

Question 27

Competitive Immunoassay (inversely or directly proportional) to unlabeled antigen concentration

Answer 27

inversely proportional

Question 28

Unknown antigen is bound by passive adsorption to the solid phase and Label activity is directly proportional with antigen concentration

Answer 28

Direct Noncompetitive Immunoassay

Question 29

Initial antigen adsorption and washing and Label activity is directly proportional with antigen concentration

Answer 29

Indirect Noncompetitive Immunoassay

Question 30

Uses known unlabeled antibody to bind the immobilized unknown antigen

Answer 30

Indirect Noncompetitive Immunoassay

Question 31

Incubated with the labeled antibody

Answer 31

Direct Noncompetitive Immunoassay

Question 32

Similar with direct immunoassay but antibody, rather than antigen is passively adsorbed on the solid phase

Answer 32

Capture/Sandwich Immunoassay

Question 33

Requires compatible known antibody pair (unlabeled and labeled) that binds different epitopes on the unknown antigen

Answer 33

Capture/Sandwich Immunoassay

Question 34

uses conjugated antibody that binds with the immobilized antigen-antibody complex on the plate well

Answer 34

Direct Capture/Sandwich Immunoassay

Question 35

uses either an unconjugated antibody or biotinylated antibody that binds to the immobilized antigen-antibody complex and subsequently detected by a secondary labeled antibody

Answer 35

Indirect Capture/Sandwich Immunoassay

Question 36

Originally designed for POCT or home-based testing

Answer 36

Rapid Immunoassays

Question 37

Designed as a single use, disposable assays in a plastic cartridge

Answer 37

Rapid Immunoassays

Question 38

Membrane based and easy to perform

Answer 38

Rapid Immunoassays

Question 39

Interpreted by looking at the formation of a colored reaction product

Answer 39

Rapid Immunoassays

Question 40

membrane material; easily immobilizes proteins

Answer 40

Nylon

Question 41

Combines all steps of rapid immunoassay in one

Answer 41

Immunochromatography