Cholesterol: Methods for Analysis

Question 1

hydrolysis of cholesterol esters

Answer 1

saponification

Question 2

reagent used in saponification

Answer 2

KOH (alcoholic potassium hydroxide)

Question 3

removal of protein interference

Answer 3

extraction

Question 4

reagent used for extraction

Answer 4

Bloor’s rgt
(3 ethanol : 1 ether)

Question 5

precipitation of free cholesterol

Answer 5

purification

Question 6

reagent used for purification

Answer 6

digitonin

Question 7

formation of colored compounds

Answer 7

colorimetry

Question 8

reagents used for colorimetry

Answer 8

• sulfuric acid (H2SO4)
• acetic anhydride (CH3CO)2O
• ferric iron

Question 9

cholestadienyl MONOSULFONIC acid and end product

Answer 9

Liebermann-Burchardt
green

Question 10

cholestadienyl DISULFONIC acid and end product

Answer 10

Salkowski
red

Question 11

CDC reference method

Answer 11

Modified Abell-Kendall

Question 12

Sample + reagent → incubate → measure the colored product using colorimeters

Answer 12

one-step method or
Pearson, Stern & Mac Gavack

Question 13

colorimetry and extraction of cholesterol

Answer 13

two-step method
Bloor’s

Question 14

colorimetry + extraction + saponification

Answer 14

three-step method

Question 15

what test uses a three-step method involving: colorimetry + extraction + saponification

Answer 15

Modified Abell-Kendall

Question 16

reagents used in Modified Abell-Kendall steps:
saponification - _____
extraction - _____
colorimetry - _____

Answer 16

saponification - alcoholic KOH
extraction - n-hexane/ petroleum ether
colorimetry - Liebermann-Burchardt

Question 17

colorimetry + extraction + saponification + purification

Answer 17

Four-step method or
Schoenheimer/Sperry

Question 18

Enzymatic method involves

Answer 18

Cholesteryl esterase
Cholesterol oxidase
Peroxidase

Question 19

Enzymatic method color is measured at

Answer 19

500 nm

Question 20

Reference Value:
<200mg/dL

Answer 20

desirable

Question 21

Reference Value:
200-239 mg/dL

Answer 21

borderline high

Question 22

Reference Value:
≥240 mg/dL

Answer 22

high

Question 23

age (years) : 2-19

moderate risk:
high risk for CHD:

Answer 23

moderate risk: ≥170 mg/dL
high risk for CHD: ≥185 mg/dL

Question 24

age (years) : 20-29

moderate risk:
high risk for CHD:

Answer 24

moderate risk: ≥200mg/dL
high risk for CHD: ≥220mg/dL

Question 25

age (years) : 30-39 moderate risk: high risk for CHD:

Answer 25

moderate risk: ≥220mg/dL high risk for CHD: ≥240mg/dL

Question 26

age (years) : 40 and above moderate risk: high risk for CHD:

Answer 26

moderate risk: ≥240mg/dL high risk for CHD: ≥260mg/dL

Question 27

hyperlipoproteinemia types 2a,2b,3; nephrotic syndrome poorly controlled DM hypothyroidism a. hypercholesterolinemia b. hypocholesterolinemia

Answer 27

a. hypercholesterolinemia

Question 28

severe liver disease malnutrition malabsorption hyperthyroidism a. hypercholesterolinemia b. hypocholesterolinemia

Answer 28

b. hypocholesterolinemia