1988 Volume 4 Issue 5 Pages 493-495
A facile technique was developed for the determination of penicillinase activity based on flow injection analysis (FIA). The analytical condition of the method utilizing a substrate (benzylpenicillin) solution as the carrier was optimized. Penicillinase solution was injected into the FIA system where the substrate was undergone enzymatic hydrolysis to form penicilloate. The decrease in the substrate was monitored at 229nm. A linear correlation was observed between a conventional photometric method and the present FIA method in the range of 0.04 to 6.6 unit ml-1. The relative standard deviations (n=18) for the determination of penicillinase at 0.07, 0.5 and 2.8 unit ml-1 were 0.65, 0.95 and 2.9%, respectively. The detection limit was 0.03 unit ml-1 with a sample size of 5μl. The FIA method was applied to the examination of penicillinase stability in solutions.