将壳聚糖同时作为氯金酸的还原剂和纳米金粒子的稳定剂,一步法绿色制备纳米金,采用紫外-可见光谱、透射电镜、红外光谱对其进行表征。采用滴涂法将壳聚糖/纳米金溶胶修饰于玻碳电极表面,构建壳聚糖/纳米金复合物修饰电极。采用循环伏安法和差分脉冲伏安法考察了修饰电极对邻苯二酚的电化学响应、检测稳定性和重复使用性。结果表明:壳聚糖浓度为0.5%(质量体积分数)、滴涂量为20μL,交联剂浓度1%(体积分数)时构建的修饰电极对邻苯二酚有最佳的电催化活性,线性范围为5μmol/L～1mmol/L,检出限为0.44μmol/L,且修饰电极有较好的重现性、稳定性和抗干扰能力。该传感器在实际样品的邻苯二酚回收率为99.2%。
Gold nanoparticles (Au NPs) were synthesized in one-step by reducing gold salt using chitosan (CTS) as dual roles of reducing and stabilizer.The obtained Au NPs were characterized with UV-Vis spectroscopy,transmission electron microscopy (TEM) and fourier transform infrared spectroscopy (FT-IR).The obtained Au colloids were applied to the modification of glassy carbon electrode (GCE) for the detection of catechol,and the preparation conditions of modified electrode were optimized.The electrochemical behaviors of catechol on the modified electrode CTS/AuNPs/GCE were investigated using cyclic voltammetry (CV) and differential pulse voltammetry (DPV).The stability and repeatability of CTS/AuNPs/GCE were investigated in detail.The results indicated that chitosan concentration 0.5%(w/v),the droppingamount of Au colloid 20μL and glutaraldehyde concentration 1.0%(v/v) were the optimal condition for preparation of CTS/AuNPs/GCE.Under the optimized condition,a linear responseto catechol in the concentration range from 5 μmol/L to 1mmol/L with the detection limit of catechol 0.44μmol/L were obtained.Interference and stability study showed a satisfactory result.The mean recovery of catechol in real samples was 99.2%.
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