IC6

Question 1

How can ELISA produce false positive results?

Answer 1

inadequate washing of unbound biomolecules, inadequate blocking of surface, off-target binding by polyclonal antibodies, cross reactivity of secondary antibodies

Question 2

How can ELISA produce false negative results?

Answer 2

enzymes or antibodies denature

Question 3

What are the 4 types of ELISA?

Answer 3

direct, indirect, sandwich and competitive

Question 4

What are immunoassays?

Answer 4

using antibodies to detect a biological molecule

Question 5

What are the 2 markers used in immunoassays?

Answer 5

radioactive label or enzymes

Question 6

What does ELISA stand for?

Answer 6

enzyme-linked immunosorbent assay

Question 7

What are the 2 types of immunoassays?

Answer 7

markers and agglutination

Question 8

Which ELISA, shows less colour when there is more antigen in sample?

Answer 8

competitive ELISA

Question 9

What is the criteria for agglutination in immunoassays?

Answer 9

either antigen or antibody must be particulate

Question 10

What are the 2 types of agglutination?

Answer 10

direct/passive and inhibition of agglutination

Question 11

What causes agglutination?

Answer 11

ab-ag binding

Question 12

How does inhibition of agglutination work?

Answer 12

standard amt of particulate antigen added (agglutinator) added. If endogeneous antigen present, it binds to ab, resulting in low absorbance as endogeneous ag is soluble. If absent, agglutinator binds to ab, resulting in high absorbance

Question 13

Is HbA1c glycosylated or glycated?

Answer 13

glycated as glucose is attached non-enzymatically to a random amino acid on haemoglobin

Question 14

What are the brands of rapid-acting insulin?

Answer 14

lispo, aspart, glulisin

Question 15

What are the brands of immediate-acting insulin?

Answer 15

NPH

Question 16

What are the brands of long-acting insulin?

Answer 16

glargine, determir

Question 17

What does pre-mixed insulin consist of?

Answer 17

a combination of rapid-acting and intermediate- acting insulin

Question 18

How is insulin modified to rapid-insulin?

Answer 18

by genetic modification to B chain of insulin, making it non-hexameric, so it dissociates faster at site of action.

Question 19

How do insulin hexamers form?

Answer 19

in the presence of zinc (In impure water)

Question 20

How is insulin modified to become long-acting?

Answer 20

made more lipophilic so it stays in sc tissue longer and enters blood later