Fabrication of dissolved O_2 metric uric acid biosensor based on uricase bound to PVC membrane

摘要

This study presents fabrication of dissolved O_2 (DO) metric uric acid biosensor based on uricase bound to PVC membrane with 87% retention of initial activity of free enzyme. Enzyme membrane conjugate was mounted over sensing part of combined electrode of DO meter (Aqualytic-OX53, Germany) to construct a uric acid biosensor, which showed optimum response within 10-12 s at pH 9.0 and 35℃. A linear relationship was found between uric acid concentration (lower cone, range, 0.1-0.8 mg/dl; higher conc, range, 1.0-10.0 mg/dl) and O_2 (mg/l) consumed. Biosensor showed mean uric acid level in serum in apparently healthy males (6.1 mg/dl) and healthy females (4.9 mg/dl). Enzyme electrode showed only 32% decrease in initial activity after 100 reuse over 60 days when stored at 4℃.