微流控芯片上大肠杆菌的电化学阻抗检测方法研究  

Determination of E.coli with Electrochemical Impedance on Homemade Microfluidic Chip

作　　者：彭金兰[1,2] 徐溢[1,2,3] 吴永杰[1,3] 传娜[1] 甘俊[1] 田鹏[2,3] 

机构地区：[1]重庆大学化学化工学院 [2]重庆大学新型微纳器件与系统技术国防重点学科实验室 [3]微纳系统及新材料技术国际研发中心,重庆大学,重庆400030

出　　处：《分析化学》2011年第9期1307-1312,共6页Chinese Journal of Analytical Chemistry

基　　金：全国博士学位论文作者专项资金基金(No.200941);国家科技部国家科技部项目(No.2010ZX09401-306-1-5);中央高校基本科研业务费(No.CDJXS1-22-00-05);重庆大学研究生科技创新基金项目(No.CDJXS10-22-11-39)资助

摘　　要：基于细菌悬浮液的阻抗特性和微流控芯片电化学阻抗检测技术,采用所构建的微流控芯片电化学阻抗分析系统,以大肠杆菌为样本,优化了扰动振幅、缓冲溶液电导率、扫描频率和新制大肠杆菌标本静置时间等参数,对大肠杆菌标本、大肠杆菌标准合成样本进行电化学阻抗检测,建立了一种大肠杆菌快速定量检测方法。在扰动振幅500 mV、缓冲溶液电导率为2.40μS/cm、扫描频率范围为100 Hz-1 MHz的条件下,大肠杆菌的测试范围为7.43×105～1.49×108 CFU/mL,检出限为7.43×104 CFU/mL。显微测试表明,在该检出限下,微流控芯片电化学阻抗分析系统对微管道检测区域内10个以上大肠杆菌就有明显响应。将所建立的方法应用于某污水中细菌检测,结果与国标法基本一致。Based on the impedance properties of bacterial suspension and microfluidic impedance analytical technology on microchip,the homemade microfluidic impedance analytical system and a rapid and simple quantitative analytical method of bacterial were proposed.In the experiment,E.coli was taken as the detecting sample.Some parameters,such as amplitude of perturbation,conductivity of buffer,scanning frequency range and time of deposition,were optimized.The impedance signals of the standards and the composite samples of E.coli were measured by the homemade microsystem.Under the conditions of perturbation at 500mV,conductivity of buffer at 2.40 μS/cm,scanning frequency ranged from 1 MHz to 100 Hz and so on,it was found that the quantitative relationship between the impedance and the concentration of the E.coli was in the range of 7.43×105 to 1.49×108 cfu/mL,and the detection limit was 7.43×104 cfu/mL.In this study,more than 10 cfu E.coli in the testing region of the microchannel on the microchip could be detected.When the concentration of the E.coli was at 1.39×107 cfu/mL,the RSD of the detection was 4.75%（n=5）.This methodology was applied to detect E.coli in sewage,the results were basically the same as that of national standard method.

关 键 词：大肠杆菌 微流控芯片 微流控电化学阻抗分析系统 定量检测 

分 类 号：TS207.4[轻工技术与工程—食品科学] O657.1[轻工技术与工程—食品科学与工程]