A specific method for serum lipase determination

It was concluded that for serum lipase determinations a substrate with an oil-water interface, such as an olive oil emulsion, must be used, which is specific, reproducible, and reasonably sensitive.

Abstract

It was concluded that for serum lipase determinations a substrate with an oil-water interface, such as an olive oil emulsion, must be used. A procedure for serum lipase determinations is presented. It is specific, reproducible, and reasonably sensitive. The incubation period is 3 h (or 1 h in emergencies). Increase of the amount of substrate to 10 ml ensures saturation of the enzyme and increases the sensitivity of the method. Purification of the oil contributes also to an increase in sensitivity and improves the accuracy. Serum lipase was found to have a pH optimum curve with several peaks of activity which, however, differ slightly in various individuals. The serum of the majority of individuals had an optimum hydrolysis when using a buffer with a pH of 8.0 (at 27°). The normal values were found to be 0.05–1.0 (conventional) units or 20 to 278 international units. Serum lipase was elevated not only in patients with pancreatitis but also in patients with retention of nitrogenous compounds due to renal or pre-renal causes.