以鱼鳔膜为基质固定葡萄糖氧化酶,偶联氧电极,构建了葡萄糖生物传感器,通过测定溶解氧浓度的变化定量测定葡萄糖。考察了酶浓度、pH值、缓冲液浓度对传感器的影响,优化了实验条件:即酶浓度为1 mg,pH 7.0,缓冲液浓度为100 mmol/L。此传感器具有较宽的线性范围(0.016~1.2 mmol/L),较短的响应时间(70 s),较低的检出限(8μmol/L),良好的重复性(2.5%,n=10)和重现性(1.2%,n=3),连续使用200次后响应信号能保持95%以上;3个月后响应信号为初始值的88.5%。此传感器已成功应用于人血清中葡萄糖含量的测定,测定结果与市售试剂盒法获得的结果相一致。回收率为95.2%~106.3%。
A glucose biosensor based on the swim bladder immobilized glucose oxidase has been deve-loped.The glucose concentration was quantified by the decrease of dissolved oxygen.The effects of enzyme loading,pH,buffer concentration and interference were studied.When the enzyme concentration was 2.0%,pH was 7.0,and the buffer concentration was 100 mmol/L,the biosensor showed a maximum response.The biosensor showed a wide linear response with a concentration range of 0.016-1.2 mmol/L,fast response time(70 s),good repeatability(2.5%,n=10) and satisfactory reproducibility(1.2%,n=3).The biosensor retained 88.5% of its initial response after 3 months,and the immobilized enzyme retained its 95% activity after 200 times used.The proposed biosensor method was successfully applied to the determination of glucose concentration in human blood serum,and the results were agreement with that obtained from a colorimetric assay kit method.The recoveries were between 95.2% and 106.3%.