Stability of Values for the Activities of Critical Enzymes Assayed in Serum Frozen for Prolonged Time Periods

    loading  Checking for direct PDF access through Ovid

Abstract

Abstract.

Objectives. Our medical center laboratory receives frozen clinical chemistry samples from outlying hospitals for which assays for critical enzyme activities are requested. Our objective is to determine the effects of freezing (-20°C) on these enzyme activities in samples over a one month period. Methods. Enzyme activities for ALP, AST, ALT, CK and LD for 30 patient's sera were stored at-20°C and were assayed on a Beckman-Coulter AU5800 analyzer at 0, 15 and 30 days after collection. Statistical tests were performed to determine if the values were statistically the same or different. Results. F-tests for all five enzyme levels showed no statistically significant differences (p>>0.05); linear regression analysis showed high correlation of results (r>0.99 for all correlations) with some bias for ALT. Conclusions. We conclude that the activities of these enzymes are stable, except possibly ALT, when stored frozen at -20°C over the 15- and 30-day storage periods.

Related Topics

    loading  Loading Related Articles