Quiz 3: Alkaline Phosphatase

Question 1

ALP functions in body, Isoenzyme/Isoform

Answer 1

Catalyzes the transphorylation of a wide variety of synthetic substrates (removes phosphate groups from ortho-phosphoric bonds).
Bone, liver, kidney, intestine and placenta major sources of ALP
Isoenzyme gene coded.
Isoform, altered form of enzyme due to posttranslational modification (glycation, siliac acid etc)

Question 2

ALP Ranges, Interferences

Answer 2

RI for total: 30-90 IU/L serum
RI for bone fraction: 7 - 30 IU/L serum
Interferences: hemolysis (6xRBC), diet, and stability

Question 3

ALP Measurement Methods

Answer 3

p-Nitrophenyl phosphate to p-Nitrophenol colorless to yellow (405nm)
ALP fractionated by electrophoresis, HLPC and heat stability