Labeled Immunoassays

Front 1

Give examples of analytes that are measured by labeled Immunoassays:

Back 1

- Bacterial antigens

- Hormones

- Drugs

- Tumor markers

- Specific immunoglobulins

Front 2

Which type of Immunoassay is often called Capture Antibody?

Back 2

Noncompetitive Immunoassays

Front 3

Which type of classification of Immunoassay involves reactants that are mixed together simultaneously?

Back 3

Competitive Immunoassays

Front 4

(COMPETITIVE or NONCOMPETITIVE):

The amount of bound label is inversely proportional to the concentration of the labeled antigen.

Back 4

Competitive Immunoassays

Front 5

(COMPETITIVE or NONCOMPETITIVE):

The amount of label measured is directly proportional to the amount of patient antigen.

Back 5

Noncompetitive Immunoassays

Front 6

Which classification of Immunoassay involves the principle of "The more label detected, the less there is of patient antigen."?

Back 6

Competitive Immunoassays

Front 7

Which classification of Immunoassay involves the principle of "Increased radioactivity/enzyme activity, decreased concentration of patient antigen."?

Back 7

Competitive Immunoassays

Front 8

Which classification of Immunoassay involves antibody that is first passively absorbed to a solid phase where unknown patient antigen is allowed to react with and be captured by the antibody?

Back 8

Noncompetitive Immunoassays

Front 9

Which classification of Immunoassay involves the principle of "Increased radioactivity/enzyme activity, increased concentration of patient antigen."?

Back 9

Noncompetitive Immunoassays

Front 10

(COMPETITIVE or NONCOMPETITIVE):

Label is always attached to Capture Antibody.

Back 10

Noncompetitive Immunoassays

Front 11

Enumerate the types of labels that serve as indicators:

Back 11

- Enzyme

- Radioisotopes

- Fluorescent dye

- Chemiluminiscent

Front 12

What is referred to as the last step common to all immunoasssays?

Back 12

Detection of the label

Front 13

Which is the first immunoassay developed?

Back 13

Radioimmunoassay (RIA)

Front 14

Which radioactive label is said to be the most popular?

Back 14

125I

Front 15

Give examples of Gamma counter radioactive labels?

Back 15

131I - Gamma counter

125I - Gamma counter

Front 16

Give examples of Beta counter radioactive labels?

Back 16

3H - Beta counter

14C - Beta counter

Front 17

Radioimmunoassay is weakly sensitive and precise: TRUE or FALSE?

Back 17

FALSE! Radioimmunoassay is extremely sensitive and precise.

Front 18

What are being measured by Radioimmunoassay?

Back 18

Radioimmunoassay measures trace amounts of analytes (such as hormones, serum proteins, and vitamins) that are small.

Front 19

In competitive Immunoassays, what is being added that stimulates the generation of a colored product? And what is the principle of this phenomenon?

Back 19

Substrate is added, and a colored product (signal) is generated with an intensity proportional to the amount of enzyme-labeled analyte bound to the antibody.

Front 20

In competitive immunoassays, the signal strength is usually directly related to the analyte concentration: TRUE or FALSE?

Back 20

FALSE! In competitive immunoassays, the signal strength is usually INVERSELY related to the analyte concentration.

Front 21

In competitive immunoassays, why is color more intense in negative result, than the position result?

Back 21

In competitive immunoassays, the color produced after the addition of substrate is more intense in negative result than in positive result because there's a high signal that is due to a high levels of enzymes that are bound to antibody against the analyte of interest.

Front 22

In competitive immunoassays, why is the color produced in positive result is less intense than negative result?

Back 22

In competitive immunoassays, the color produced in negative result after the addition of substrate is less intense than that of the positive result because there is a low signal due to a less enzyme labeled antigen bound to the antibody against the analyte of interest.

Front 23

In competitive immunoassays, what is the relationship between the signal and the analyte concentration?

Back 23

• High signal = Less analyte concentration

• Low signal = High analyte concentration

Front 24

In noncompetitive immunoassays, antibody is first passively absorbed to a _____:

Back 24

Solid phase

Front 25

In noncompetitive immunoassays, what is being added after washing to remove unbound antigen?

Back 25

Second antibody with a label

Front 26

Gamma counters have half life of:

Back 26

60 days

Front 27

In radioimmunoassay (RIA), radioactivity is measured by two methods. What are those?

Back 27

- Scintillation counter

- Gamma counter

Front 28

Describe enzyme labels:

Back 28

- Highly stable

- Has extreme specificity

- Cannot be altered by inhibitors

Front 29

Give three examples of enzymes used in Enzyme Immunoassays:

Back 29

- Alkaline phosphatase

- Horseradish peroxidase

- Beta-galactosidase

Front 30

In Enzyme Immunoassays alkaline phosphatase and horseradish peroxidase have low sensitivity and are difficult to detect: TRUE or FALSE?

Back 30

FALSE! Alkaline phosphatase and horseradish peroxidase are highly sensitive and are easy to be detected.

Front 31

Heterogenous enzyme Immunoassays require a step to physically separate free analyte from bound analyte: TRUE or FALSE?

Back 31

True!

Front 32

Which type of heterogenous enzyme immunoassay is easily applied to POCT?

Back 32

Non-competitive enzyme immunoassay

Front 33

Which type of heterogenous enzyme immunoassay is involves enzyme-labeled antigen competing with unlabeled patient antigen for binding sites on antibody molecules?

Back 33

Competitive enzyme immunoassay

Front 34

Which specific assay in Enzyme Immunoassays involves antigen being bound to the solid phase?

Back 34

Enzyme-linked immunosorbent assay (ELISA)

Front 35

In ELISA, if no patient antibody is bound to the solid phase,nthe second labeled antibody will be bound: TRUE or FALSE?

Back 35

FALSE! if no patient antibody is bound to the solid phase,nthe second labeled antibody will not be bound

Front 36

In ELISA, the amount of color, fluorescence, or luminescence is measured; this amount is inversely proportional to the amount of antibody in the specimen: TRUE or FALSE?

Back 36

FALSE! the amount of color, fluorescence, or luminescence is measured; this amount is directly proportional to the amount of antibody in the specimen.

Front 37

I'm enzyme immunoassay, capture assay is also called:

Back 37

Sandwich Immunoassays

Front 38

What assay is best suited to antigens that have multiple determinants?

Back 38

Capture assays (sandwich Immunoassays)

Front 39

In capture assays, the second antibody recognizes a different epitope or binding site than the solid-phase antibody and completes the ______:

Back 39

Sandwich

Front 40

In sandwich immunoassays, either a colored or chemiluminescent reaction product is detected: TRUE or FALSE?

Back 40

True!

Front 41

In capture assays, enzymatic activity is directly proportional to the amount of antigen in the test sample: TRUE or FALSE?

Back 41

True!

Front 42

Both homogenous and heterogenous enzyme immunoassays require a washing or separation step: TRUE or FALSE?

Back 42

FALSE! Only heterogenous enzyme immunoassay requires washing or separation step; homogenous enzyme immunoassay do not require a washing or separation step.

Front 43

In homogenous enzyme immunoassay, when antibody binds specific determinant sites on the antigen, the active site on the enzyme is blocked, resulting in a measurable high levels of activity: TRUE or FALSE?

Back 43

FALSE! When antibody binds specific determinant sites on the antigen, the active site on the enzyme is blocked, resulting in a measurable loss of activity.

Front 44

Homogenous enzyme immunoassay is more sensitive than heterogenous enzyme immunoassay; TRUE or FALSE?

Back 44

FALSE! Homogenous easy Immunoassays are less sensitive than heterogenous assays.

Front 45

Enumerate the low-molecular-weight analytes in serum and urine determined using homogenous enzyme immunoassay:

Back 45

- Hormones

- Therapeutic drugs

- Drugs of abuse

Front 46

Which homogenous enzyme Immunoassay was developed by the SYVA corporation?

Back 46

Enzyme Multiplied Immunoassay Technique (EMIT)

Front 47

Homogenous enzyme immunoassay can be interfered by:

Back 47

- Endogenous enzyme activity

- Cross-reacting antigens

- Enzyme inhibitors

Front 48

What is referred to as a membrane-based, single-use, and disposable assays?

Back 48

Rapid Immunoassays

Front 49

In membrane-based cassette assays, membrane is usually ____:

Back 49

Nitrocellulose

Front 50

Which assay is said to be as restricted to qualitative observations involving the use of a fluorescence microscope?

Back 50

Immunofluorescent assay

Front 51

Which assay is used for rapid identification of microorganisms in cell culture or infected tissue, tumor-specific antigens on neoplastic tissue, and transplantation?

Back 51

Immunofluorescent assays

Front 52

Immunofluorescent assay involves grading the amount of fluorescence against _____:

Back 52

Immunofluorescent assay involves grading the amount of fluorescence against a dark background.

Front 53

Who was known to conceptualize Immunofluorescent assay?

Back 53

Albert Coons

Front 54

Enumerate examples of fluorochromes used in immunofluorescent assay:

Back 54

- FITC (Fluorescein Isothiocyanate) - Green

- Phyocyanin - Red

- Texas Red - Red

- Tetramethyl Rhodamine - Orange-Red

Front 55

Enumerate the devices/instruments that can be used in immunofluorescent assay:

Back 55

- Flow cytometer

- Fluorometer

- Fluorescence microscope

Front 56

In Direct immunofluorescent assay/single layer technique, what is added directly to unknown antigen that is fixed to a microscope slide?

Back 56

Antigen that is conjugated with a fluorescent tag

Front 57

Which type of fluorescent assay demonstrates the presence of pathogens in patient samples?

Back 57

Direct immunofluorescent assay

Front 58

Which type of fluorescent Immunoassay involves a sandwich formed with the first antibody that localizes the fluorescence?

Back 58

Indirect Immunofluorescent assay

Front 59

Which assay is used to determine the concentrations of therapeutic drugs and hormones?

Back 59

Fluorescence Polarization Immunoassay (FPIA)

Front 60

In FPIA, if the labeled molecule is bound to antibody, the molecule emits a decreased amount of polarized light: TRUE or FALSE?

Back 60

FALSE! if the labeled molecule is bound to antibody, the molecule emits an increased amount of polarized light

Front 61

What is the most common disadvantage of FPIA?

Back 61

Quenching or any processes that decrease fluorescence

Front 62

Which assay is employed to follow antigen-antibody combination?

Back 62

Chemiluminescent Immunoassays

Front 63

Which assay can be used for heterogeneous and homogeneous assays because labels can be attached to either antigen or antibody?

Back 63

Chemiluminescent Immunoassays

Front 64

Chemiluminescent Immunoassays involves the emission of light caused by a chemical reaction, typically an oxidation reaction, producing an exited molecule that decays back to its original ground state: TRUE or FALSE?

Back 64

True!

Front 65

Which enzyme is the BEST in terms of turnover and conversion rates?

Back 65

Alkaline Phosphatase

Front 66

Which assay has an INDIRECT correlation with the signal and the product?

Back 66

Enzyme-Linked Immunosorbent Assay (ELISA)

Front 67

Which fluorophore will give off an ORANGE-RED fluorescence?

Back 67

Tetramethyl Rhodamine

Front 68

What is the most commonly used radioactive label for Radioimmunoassay?

Back 68

Iodine 125

Front 69

What is used to measure the activity of enzyme immunoassay?

Back 69

Spectrophotometer

Front 70

What is used to measure activity of Chemiluminescence assays?

Back 70

Luminometer