A molecularly electrochemical sensor (N-CTS/MWNTs/GCE )was prepared using N-acyl chitosan (N-CTS )and multi walled carbon nanotubes(MWNTs)modified glassy carbon electrode. Cyclic voltammetry was applied to study the electrochemical behaviors of dopamine (DA )and quercetin (QU )on the modified N-CTS/MWNTs/GCE electrode Results showed that N-CTS/MWNTs/GCE could greatly improve the oxidation peak currents of both DA and QU. Linear response relationship between the peak current and the concentration of analytes could be established for dopamine and quercetin,as respectively measured in pH=7. 38, 6. 80 phosphate buffer solution. Linear equations can be described as followed:Ip(DA)=0. 0397+4715. 8673c and Ip(QU)=-0. 2645+256. 8935c. The correlation coefficients for these two equations are all larger than 0. 997. The detection limits of dopamine and quer-cetin are 1. 0× 10-8mol·L-1and 1. 0× 10-6mol·L-1,respectively. This method hold many merits:good reproducibility,high stabil-ity,and peak current of RSD=1. 51％. We believe that the developed method can be applied for the detection of dopamine and quercetin in medicines.%通过N-酰化壳聚糖(N-CTS)与多壁碳纳米管(MWNTs)复合修饰玻碳电极得到N-CTS/MWNTs/GCE电化学传感器.采用循环伏安法研究了多巴胺(DA)和槲皮素(QU)在修饰电极上电化学行为.结果表明:N-CTS/MWNTs/GCE电极能显著提高DA、QU的氧化峰电流,降低其氧化峰电位.在pH分别为7.38、6.80磷酸盐缓冲溶液中,DA、QU的氧化峰电流与浓度存在线性关系,线性方程分别为:Ip(DA)=0.0397+4715.8673 c、Ip(QU)=-0.2645+256.8935 c,相关系数均大于0.997,多巴胺、槲皮素检测限分别达1.0×10-8mol·L-1和1.0×10-6 mol·L-1.N-CTS/MWNTs/GCE电极具有较好的重现性、稳定性,相对标准偏差为1.51％.该修饰电极可用于含DA、QU成分药物的直接测定.
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