基于顺序注射分析法的丝网印刷型生物传感器系统的研究

Screen-printed Biosensor System Based on Sequential Injection Analysis Method

采用顺序注射分析（SIA）与丝网印刷生物传感器联用法,考察辣根过氧化物酶（HRP）催化邻苯二胺（OPD）-H2O2反应体系。利用牛血清白蛋白（BSA）和戊二醛形成的交联大分子,将HRP固定于丝网印刷电极表面,制备成HRP电极,通过对缓冲液pH值及浓度、泵流速、样品量进行优化,建立用于检测HRP对H2O2与OPD的催化动态响应曲线的SIA与时间-电流（i-t）相结合的分析方法。结果表明：在实验反应的最适条件（泵流速153.9 mL/min、样品量100 mL、0.1 mol/L PBS缓冲液（pH 6.5））下,电流响应值随H2O2浓度增加而增大,HRP酶电极测定H2O2的浓度线性范围是0.1~1.0 mmol/L,呈现良好的线性关系。该酶电极重现性良好,RSD为3.8%,用于实际水样回收率测定时,回收率大于60%。

The reaction system of horseradish peroxidase（HRP） catalyzing o-phenylenediamine（OPD）-H2O2 using biosensor coupled with sequential injection analysis（SIA） was studied.The biosensor was screen printed electrode immobilized with bovine serum albumin（BSA） and glutaraldehyde.After HRP sensor on the SIA system,the experiment of sensor′s dynamic response for H2O2-OPD was studied,including a series of optimization,such as the buffer pH and concentration,pump flow rate,sample volume.The result showed that under the optimum conditions of the experiment,including flow rate of 153.9 mL/min,sample volume of 100 mL and the buffer of pH 6.5（0.1 mol/L）,the HRP biosensors has a linear response in the range of 0.1-1.0 mmol/L for concentration of H2O2.The current response curve increased with the increase of the concentration of H2O2.In addition,the biosensor had the advantages of repeatability with RSD of 3.8%.The recovery ration for OPD in the real sample was more than 60%.