Estimation of the Fish Freshness Using a Xanthine Oxidase Electrode with Silk Membrane

摘要

The traditional determination of fish freshness is to detect total volatile basic nitrogen, microbial load or hypoxanthine. These methods are complex and expensive. A enzyme electrode hypoxanthine biosensor was constructed by using immobilised xantine oxidase and a platinum electrode. The enzyme was immobilised on a silk membrane. The electrode detected the hydrogen peroxide released during the enzymatic reaction. A linear range from 0.05x10~-6 to 100x10~-6m of hypoxanthine was obsrved. When the method was applied to fish sasmples, the results obtained agreed well with those obtained by the conventional total volatile basic nitrogen and microbial load. This enzyme electrode provides a reliable, simple, rapid and economical method for the measurement of fish freshness.