2.1 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

In labelled immunoassay, one of the components of antigen-antibody reaction is usually very low/small in concentration that it cannot be detected in the naked eye

T or F?

Answer 2

T

Question 3

What are the types of labels?

Answer 3

Radionuclides
Enzymes
Fluorochromes
Luminescents

Question 4

Most common types of labels

Answer 4

Enzymes

Question 5

Used in radioactive labels where atoms with unstable niclei that spontaneously emit radiation

cannot be influenced by any other factors

Answer 5

Radionuclides

Question 6

What is used in Beta radiation?

Answer 6

3H (Tritium)

Question 7

Most common radionuclides for diagnosis and research in cellular immunology?

Answer 7

Tritium

Question 8

What is used in Gamma radiation?

Answer 8

125I (iodine 125)

Question 9

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

Answer 9

125I

Question 10

Gamma radiation is detected using what measuring tool?

Answer 10

Crystal Scintillation counter

Question 11

Radioimmunoasay is developed by?

Answer 11

Yalow and Berson (1950s)

Question 12

This assay is originally used to determined insulin-anti-insulin complexes in diabetic patients

Answer 12

Radioimmunoassay

Question 13

Useful in measuring analytes occuring at trace concentrations

Answer 13

Radioimmunoassay

Question 14

Alternative for RIA?

Answer 14

Enzyme labels

Question 15

react with suitable substrate to produce breakdown products that are either chromogenic, fluorogenic, or luminescent.

Answer 15

Enzyme labels

Question 16

Example of enzyme labels?

Answer 16

Horseradish peroxidase
Alkaline phosphatase
B-D-galactosidase

Question 17

Most common enzyme labels?

Answer 17

Horseradish peroxidase

Question 18

What is the component for the enzyme labels where addition of this causes colorimetric?

Answer 18

Substrate

Question 19

1. Once binding agent (antibody) binds to the antigen, Ab will now become immobilized.
2. Then we add a new antibody (AHg) so it can attach to the Fc portion of an unknown Ab.
3. Once attached, it will be immobilized as well.
4. Since the enzyme molecule is exposed, we will add a substrate for the
   enzyme (either colorimetric or chemiluminescent)

Arrange the order

Answer 19

1234

Question 20

Fluorescent labels uses?

Answer 20

Fluorochromes / Fluorophores

Question 21

Common fluorescent compounds uses is usually in what form?

Answer 21

Isothiocyanate

Question 22

Common fluorescent compounds that has yellow green color?

Answer 22

Fluorescein

Question 23

Common fluorescent compounds that has yellow orange color?

Answer 23

Auramine Rhodamine

Question 24

Direct immunofluorescence assay uses what sample?

Answer 24

Tissues

Question 25

Indirect immunofluorescence assay uses what sample?

Answer 25

Serum or plasma

Question 26

Fluorochromes emit light when subjected to?

Answer 26

UV radiation

Question 27

What is unknown in Direct immunofluorescence assay?

Answer 27

Antigen

Question 28

What is unknown in Indirect immunofluorescence assay?

Answer 28

Antibody

Question 29

Uses labels that emit light as the result of electrical or chemical reaction?

Answer 29

Chemiluminescence immunoassays

Question 30

The is the chemical reaction to emit light in chemiluminescence?

Answer 30

Oxidation

Question 31

Example of luminescent labels?

Answer 31

Luminol Acridinium ester Ruthenium derivatives Nitrophenyl oxalates

Question 32

Uses electrochemical compounds that penetrate light when redox reactions occurs

Answer 32

Electrochemiluminescence immunoassay

Question 33

Measures the degree of color change of substrate

Answer 33

ELISA

Question 34

* Reactants are mixed simultaneously * Labeled antigen competes with unlabelled antigen for a limited number of antibody-binding sites * Concentration of labeled antigen is in excess to occupy all antibodybinding sites * Label activity is measured to determine unlabeled antigen concentration (Inversely proportional)

Answer 34

Competitive assay

Question 35

* Unknown antigen is bound by passive adsorption to the solid phase * Any unbound antigen is removed by washing * Incubated with the labeled antibody * Label activity is directly proportional with antigen concentration

Answer 35

Direct noncompetitive assay

Question 36

* Initial antigen adsorption and washing is similar with direct method * Uses known unlabeled antibody to bind the immobilized unknown antigen * Following washing to remove unbound antibodies, known labeled antibodies are added * Label activity is directly proportional with antigen concentration

Answer 36

Indirect Noncompetitive assay

Question 37

The higher the label activity, the lower the concentration of your unlabeled antigen Compe or noncompe

Answer 37

Compe

Question 38

The amount of labeled activity is directly proportional with the concentration of unknown substance or analyte Compe or Noncompe

Answer 38

noncompe

Question 39

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

Answer 39

Capture immunoassay

Question 40

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

Answer 40

Direct capture immunoassay

Question 41

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

Answer 41

Indirect capture immunoassay

Question 42

Single use, disposable assays in a plastic cartridge that formerly for PCO/home based testing

Answer 42

Rapid immunoassay

Question 43

Membrane mateiral used in Rapid immunoassays

Answer 43

Nylon

Question 44

Combination of all steps in rapid immunoassay into one

Answer 44

Immunochromatography