Lipase Flashcards
Lipases are
enzymes which hydrolyze glycerol esters of long fatty acids. The enzyme and its cofactor colipase are produced in the pancreas, lipase being also secreted in small amounts by the salivary glands as well as by gastric, pulmonary and intestinal mucosa.
Bile acids and colipase form
micellar complexes with the lipids and bind lipase on the substrate/water interface.
Method
Enzymatic color test
A synthetically produced lipase substrate (1,2-o-dilauryl-rac-glycero-3-glutaric acid-(6-methylresorufin) ester) is added to a micro-emulsion which is specifically split by lipase in the presence of colipase and bile acids. The combination of lipase and bile acids make this specific and reliable for pancreatic lipase without any reaction due to lipolytic enzymes or esterases. The reagent composition has been thoroughly optimized to avoid serum matrix effects. The generated methylresorufin ester is spontaneously degraded to methylresorufin. The absorbance by this red dye is directly proportional to the lipase activity in the sample.
R1:
Good’s buffer
Taurodesoxycholate
Desoxycholate
Calcium chloride
Colipase (porcine)
R2:
Tartrate buffer
Taurodesoxycholate
Color substrate
Warnings and Precautions
H319 Causes serious eye irritation.
P280 Wear protective gloves/protective clothing/eye protection.
P305+P351+P338 If in eyes: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continue rinsing.
P337+P313 If eye irritation persists: Get medical advice/attention.
Specimen
Human serum or heparin plasma
Wavelength
571/805 nm
Conversion Factor
0.0167 = Lipase [µkat/L]
Interfering substance
Ascorbic acid
Bilirubin (conjugated)
Bilirubin (unconjugated)
Hemoglobin
Lipemia
N-acetylcysteine
Reference Range
≤ 60 U/L
≤ 1.00 µkat/L
