Immunochemical Techniques

Question 1

Competitive formats use ____ reagents (Ab or other Ag binder)

Answer 1

Limited

Question 2

Noncompetitive formats use ____ reagents (Ab or other Ag binder) and are two-site or “____” assays

Answer 2

Excess; sandwich

Question 3

What does it mean that competitive immunoassays are simultaneous?

Answer 3

All reactants are mixed together simultaneously or at the same time

Question 4

Simultaneous competitive immunoassay

- Principle

Answer 4

Labeled and unlabeled Ag compete for a limited number of binding sites on an Ab titer
- Avidity for Ab is the same for both

Question 5

Simultaneous competitive immunoassay

- Proportionality observed b/w bound labeled and unlabeled Ag concentrations

Answer 5

The probability of labeled Ag binding to the Ab binder is inversely proportional to unlabeled Ag

Question 6

Simultaneous competitive immunoassay

- Examples of tests

Answer 6

• RIA
• FIA
• EIA

Question 7

Noncompetitive immunoassay

- Principle

Answer 7

A captured Ab is bound to a solid phase. Unlabeled Ag reacts with the solid phase Ab, then there’s a washing step. Labeled Ab is added; it reacts with the unbound Ag on a 2nd and distinct epitope. Another washing step occurs, and the amount of the bound label is determined

Question 8

Noncompetitive immunoassay

- Proportionality observed b/w bound labeled and unlabeled Ag concentrations

Answer 8

Directly proportional

Question 9

What is the difference of a heterogeneous immunoassays from homogeneous immunoassays?

Answer 9

• Heterogeneous require a separation step to separate the bound label from the free, unbound reactants
• Homogeneous do not require a separation step

Question 10

EMIT

- What does it stand for?

Answer 10

Enzyme-Multiplied Immunoassay Technique

Question 11

EMIT

- What does it detect?

Answer 11

Change in absorbance after adding substrate

Question 12

EMIT

- Homogeneous or heterogeneous?

Answer 12

Homogeneous

Question 13

EMIT

- Proportionality

Answer 13

Direct

Question 14

ELISA

- What does it stand for?

Answer 14

Enzyme-Linked Immunosorbent Assay

Question 15

ELISA

- What does it detect?

Answer 15

Change in absorbance

Question 16

ELISA

- Homogeneous or heterogeneous?

Answer 16

Heterogeneous

Question 17

ELISA

- Proportionality

Answer 17

Direct or indirect

Question 18

MEIA

- What does it stand for?

Answer 18

Microparticle Enzyme Immunoassay

Question 19

MEIA

- What does it detect?

Answer 19

Fluorescence

Question 20

• *MEIA**

- Homogeneous or heterogeneous?

Answer 20

Heterogeneous

Question 21

MEIA

- Proportionality

Answer 21

Direct

Question 22

FIA

- What does it stand for?

Answer 22

Fluorescent immunoassays

Question 23

FIA

- What does it detect?

Answer 23

Fluorescence

Question 24

FIA

- Homogeneous or heterogeneous?

Answer 24

Heterogeneous

Question 25

FIA

- Proportionality

Answer 25

Direct or indirect

Question 26

FPIA

- What does it stand for?

Answer 26

Fluorescence Polarization Immunoassay

Question 27

FPIA

- What does it detect?

Answer 27

Plane polarized light

Question 28

FPIA

- Homogeneous or heterogeneous?

Answer 28

Homogeneous

Question 29

FPIA

- Proportionality

Answer 29

Indirect

Question 30

FPIA

- Most common fluorescent label

Answer 30

FITC

Question 31

Chemiluminescence

- What does it detect?

Answer 31

Visible light produced from labels after a base is added and is measured by a luminometer

Question 32

Chemiluminescence

- Proportionality

Answer 32

Direct

Question 33

Chemiluminescence

- Two common labels

Answer 33

• Luminol

- Acridinium ester