Optimization and characterization of a flow injection electrochemical system for pentachlorophenol assay.
Optimization and characterization of a flow injection electrochemical system for pentachlorophenol assay.
复制标题
DOI：
10.1021/ac980266c
复制
发表时间：
1998-10
影响因子：
7.4
通讯作者：
K. Male;C. Saby;John H. T. Luong
中科院分区：
文献类型：
--
作者：
K. Male;C. Saby;John H. T. Luong
建立了一种流动注射电化学检测系统，并对该系统进行了优化，用于污染土壤中五氯酚的测定。在环境温度下，在0.1 M酒石酸（pH 2.0）中使用双（三氟乙酰氧基）碘苯将五氯苯酚氧化为四氯-1，4-苯醌（1，4-TCBQ），产率较高。在与固定化葡萄糖氧化酶快速反应后，当还原形式的1，4-TCBQ或四氯-1，4-氢醌在玻碳电极表面再氧化为1，4-TCBQ（+0.40 V vs Ag/AgCl）时，完成了检测和扩增方案。酶和葡萄糖底物之间的快速电子交换提供了朝向电极的非速率限制电流。FI电化学系统对1 μ M氧化PCP呈线性，检测限为10 nM，在14 h连续运行中，重复分析165次，重现性为± 0.6%。当应用于PCP污染的土壤样品，从FI电化学系统得到的结果相比，以及与HPLC标准方法。
A flow injection (FI) electrochemical detection system has been developed and optimized for the determination of pentachlorophenol (PCP) in contaminated soil. PCP was oxidized to tetrachloro-1,4-benzoquinone (1,4-TCBQ) with a high yield using bis(trifluoroacetoxy)iodobenzene in 0.1 M tartaric acid, pH 2.0, at ambient temperature. Upon rapid reaction with immobilized glucose oxidase, the detection and amplification scheme was completed as the reduced form of 1,4-TCBQ or tetrachloro-1,4-hydroquinone was reoxidized to 1,4-TCBQ at the surface of the glassy carbon electrode (+ 0.40 V vs Ag/AgCl). Rapid electron exchange between the enzyme and its glucose substrate provided a non-rate-limiting current toward the electrode. The FI electrochemical system was linear up to 1 μM oxidized PCP with a detection limit of 10 nM and exhibited a reproducibility of ±0.6% over 165 repeated analyses during 14 h of continuous operation. When applied to PCP-contaminated soil samples, the results obtained from the FI electrochemical system compared well with those of the HPLC standard method.