A Biosensor Based on Swim-Bladder Membrane as Substrate for Determination of Glucose

A glucose biosensor based on swim bladder-immobilized glucose oxidase has been developed. The glucose concentration was quantified by the decrease of dissolved oxygen. The effects of enzyme loading, pH value, buffer concentration, and interference were studied in detail. The biosensor showed a wide linear relationship within a concentration range of 0.016-1.2 mM, a fast response time (70 s), good repeatability (2.50%, n = 10), and satisfactory reproducibility (1.15%, n = 3). The biosensor retained 88.5% of its initial response after three months, and the immobilized enzyme retained 95% of its activity even after 200 uses. The proposed biosensor method was successfully applied to the determination of glucose concentrations in human serum, and the results were in agreement with those obtained from a colorimetric assay kit. In addition, the recoveries were between 95.2% and 106.3%.