A FIBER OPTIC BIOSENSOR FOR URIC-ACID BASED ON IMMOBILIZED ENZYMES

A simplified enzyme based fiber optic uric acid biosensor is reported. It is constructed by coimmobilizing uricase and horseradish peroxidas e [HRP] to bovine albumin via glutaraldehyde. A new fluorimetric subst rate,thiamine,is used to indicate the sensing process. Under optimized conditions, the linear range of uric acid concentration is 0.5 to 5.0 ug/mL with a correlation coefficient of 0.997, and the detection limi t is 0.15 ug/mL with excellent reversibility and stability. The sensor can be used at least two months at room temperature. It is possibly t o determine uric acid directly in serum and urine samples with satisfa ctory results.