ALP Determination Quiz & Flashcards

Study Notes

Chemical Reagents and Colorimetry

2,4-Dinitrophenyl hydrazine (2,4-DNPH) produces a yellow to orange color upon reaction, indicating the presence of carbonyl compounds.
The Rietmann Frankel test utilizes colorimetry, which measures absorbance of light to quantify substances, based on the principle that absorbance is directly proportional to concentration.

Enzymatic Activity

Gamma-glutamyl transferase (GGT) activity is found in highest concentrations in the liver and biliary system.
Alanine aminotransferase (ALT) was formerly known as serum glutamate-pyruvate transaminase (SGPT).
ALT belongs to the class of enzymes known as transferases, specifically those that facilitate amino group transfer.

Analytical Methods

The Walker method is a specific technique used to determine total ALT activity, providing accurate quantification in serum samples.
Lipase is an enzyme responsible for breaking down fats (lipids) into fatty acids and glycerol for absorption and metabolism.

Impact of Conditions on Enzyme Activity

Serum lipase activity can be impacted negatively by hemolysis, as it may lead to protein degradation and altered test results.
The reference range for lipase activity typically varies but commonly falls around 0 to 160 U/L, dependent on the specific laboratory protocols.

Stability of GGT

GGT activity shows good stability at 4°C for up to several days, allowing for retention of enzymatic function during storage prior to testing.

Description

This quiz covers the discussion-based continuation of ALP determination, focusing on liver enzymes such as Alanine Aminotransferase (ALT). Topics include molar absorptivity, absorbance measurement, and the functions and tissue sources of ALT. This is part of the second semester lab midterm for Clinical Chemistry 2.