1,2-Dioleoylglycerol method for pancreatic lipase catalytic activity in serum.
Clin Chem Lab Med 2011;
50:475-81. [PMID:
22126376 DOI:
10.1515/cclm.2011.811]
[Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2011] [Accepted: 11/11/2011] [Indexed: 11/15/2022]
Abstract
BACKGROUND
There is a need for a pancreatic lipase (LIP) reference assay to provide an accurate base to which routine methods can be traceable.
METHODS
This study developed a novel LIP assay method in which 1,2-dioleoylglycerol (DODG) is the substrate and LIP activity is measured in a coupled enzymatic reaction from the increase in absorbance at 340 nm with production of NADPH.
RESULTS
With this method, LIP activity was linear up to 440 U/L (8-times expected upper limit of physiological concentration). When assayed manually, the between-laboratory variation for six samples surveyed at five laboratories was 3.80-26.4% (CV) for samples containing about 20-290 U/L LIP activity; when assayed using an automated analyzer, the range was 1.86-4.86% (four laboratories). Interference by >5 mmol/L glycerol and low specificity with post-heparin samples were noted, but in practice these are avoidable. Precision analyzed by automated assay of 49 samples twice in random order produced a covariance of 2.27 U/L, which is comparable to routine methods, and good correlations were obtained with five routine methods.
CONCLUSIONS
Although further studies are required, the DODG method may be likely applicable as one candidate reference method.
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