摘要
为改善免疫传感器的生物相容性和反应信号强度,采用恒电位沉积法将HAuCl4直接还原成纳米金,并修饰于四通道丝网印刷碳电极(4-SPCE)表面。以质量浓度为0.05g/L和HAuCl4和电沉积时间30s作为电沉积纳米金修饰4-SPCE的制备条件。利用静电吸附作用将辣根过氧化物酶标记副溶血性弧菌抗体(HRP-anti-VP)固定,制备副溶血性弧菌酶免疫电极。通过循环伏安法表征免疫电极和监测酶促反应,根据免疫反应前、后还原峰电流下降的比例(DP)来实现对VP的检测。在优化的免疫反应条件及电化学检测条件下,免疫电极线性检测范围为104～109cfu/mL,其线性回归方程为:DP=7.7lgC-12.63,线性相关系数为0.9973(n=6),检测限为8.1×104cfu/mL(S/N=3)。该免疫电极具有较好的特异性、重现性(RSD<6%)、稳定性(1周后电流响应为初始值的90%)和准确性(与GB/T4789.7-2003符合率93.3%)。所研制的免疫传感器用于快速筛检VP效果良好。
In order to improve the biocompatibility and strength of response signals of immunosensor, a nano-Au modified electrode was prepared by constant potential deposition method which was obtained by direct reduction of HAu- C14 onto the four-channels screen-printed carbon electrode surface. The preparation condition of electric deposition nano- Au modified 4-SPCE had been selected. The concentration of HAuC14 was 0.05 g/L and the electric deposition time was 30s. The enzyme immunosensor was fabricated by immobilizing horeseradish peroxidase labeled Vibrio parahaemolyticus antibody （HRP-anti-VP） on the surface of nano-Au modified 4-SPCE through electrostatic adsorption. The immunosensor was characterized by cyclic vohammetry. VP could be detected according to the decrease percentage（DP） of peak current befiu＇e and after immune response, while cyclic voltammetry was used as an electrochemical mean to detect the products of the enzymatic reaction. Under the optimum conditions of immunoreaction and electrochemical detection, the decrease percentage（DP） of peak current before and after immune response had a linear relation with lgC in the range of 10^4-10^9 cfu/mL, the linear regression equation was： DP=7.71gC-12.63, the correlation coefficient was 0.9973 （n=6） and the detection limite was 8.1×10^4cfu/mL（S/N=3）. The inmmnosensor possessed acceptable specificity, reproducibility（RSD〈6%）, stability （the amperometric response was 90% of the initial response after a week） and accuracy （93.3% of the results obtained by the immunosensor were in agreement with those obtained by GB/T 4789.7-2003）. Therefore, the immunosensot gave a good performance in rapid detection of Vibrio par^aemolyticus.
出处
《中国食品学报》
EI
CAS
CSCD
北大核心
2009年第4期8-14,共7页
Journal of Chinese Institute Of Food Science and Technology
基金
国家十一五重点支撑项目(No.2006BAD27B09)
关键词
电沉积纳米金
四通道丝网印刷碳电极
电化学免疫传感器
副溶血性弧菌
循环伏安法
Electric deposition nano-Au Four-channel screen-printed carbon electrode Electrochemical immunosensor Vibrio parahaemolyticus Cyclic voltammetD~
