Qin W, Zhang Z, Liu H
Department of Chemistry, Nanjing University, China.
Anal Chem. 1998 Sep 1;70(17):3579-84. doi: 10.1021/ac970917p.
A novel chemiluminescence (CL) flow-through sensor based on immobilizing all the ingredients involved in the analytical reaction for the determination of copper is proposed. The analytical reagents including luminol and cyanide were coimmobilized permanently on an anion-exchange column, while the analyte copper was retained temporarily by electrochemical preconcentration on a gold electrode placed in an anodic stripping voltammetric flow cell. By injection of a volume of sodium hydroxide through the column with immobilized reagents, luminol and cyanide were eluted from the resins in alkaline aqueous solution and then reacted with copper stripped from the gold electrode to produce a CL signal, by means of which copper could be sensed. The sensor was not susceptible to interference by other metal ions associated with the CL reaction. The response to the concentration of copper was linear in the range of 0.01-10 micrograms/L and an extremely low detection limit of 8.0 x 10(-3) micrograms/L was achieved. A complete analysis could be performed in 4 min with a relative standard deviation of less than 8%. The column with immobilized reagents was readily prepared and could be reused over 200 times. The sensor was applied successfully to the determination of copper in human serum and natural water samples.
本文提出了一种新型化学发光（CL）流通式传感器，该传感器基于固定分析反应中所有参与成分来测定铜。分析试剂包括鲁米诺和氰化物被永久共固定在阴离子交换柱上，而分析物铜则通过阳极溶出伏安流通池中的金电极进行电化学预富集而暂时保留。通过将一定体积的氢氧化钠注入装有固定试剂的柱子，鲁米诺和氰化物在碱性水溶液中从树脂上洗脱下来，然后与从金电极上溶出的铜反应产生CL信号，借此可以检测铜。该传感器不易受到与CL反应相关的其他金属离子的干扰。对铜浓度的响应在0.01 - 10微克/升范围内呈线性，检测限极低，达到8.0×10⁻³微克/升。一次完整分析可在4分钟内完成，相对标准偏差小于8%。装有固定试剂的柱子易于制备，可重复使用200多次。该传感器已成功应用于人体血清和天然水样中铜的测定。
