应用电泳中介微分析(EMMA)技术,构建聚二甲基硅氧烷(PDMS)芯片自由酶反应器,在线检测葡萄糖(Glu),在十字形的芯片通道上,采用自制的碳纤维微电极检测葡萄糖氧化酶(GOD)催化氧化Glu生成的H2O2,并对检测电位、GOD浓度、GOD进样时间、分离电压等参数进行了优化,测定了该自由酶反应器的线性范围和检出限,考察了其重现性及稳定性。结果表明,此自由酶反应器制作方便,操作简单,重现性好,Glu浓度在0.1~20mmol/L之间有较好的线性关系(r=0.997),检出限为19.8μmol/L(S/N=3)。
Microfluidic enzyme-based reactor could be used to detect the biomolecules with high sensitivity and selectivity. Based on the electrophoretic mediated microanalysis (EMMA) method, a new kind of free enzyme-based poly(dimethylsiloxane) (PDMS) microchip was developed to detect glucose (Glu). On-line catalysis reaction of Glu by glucose oxidase (GOD) was carried out on the chip. The product H2O2 was detected using single carbon fibre cylindrical electrode. Factors influencing the separation and detection, such as detection potential, GOD concentration, GOD injection time and separation voltage, were investigated and optimized. Results showed that the peak current had a good linear relationship with Glu concentration in the range of 0.1-20 mmol/L (R=0.997). The detection limit of Glu was 19.8 μmol/L (S/N=3). In addition, the PDMS enzyme-based reactor had long-term stability and excellent reproducibility (RSD=2.02%, n=10). It was easy to fabricate and operate, which showed great potential application in bioanalysis.