Series dual-electrode detector for liquid chromatography/electrochemistry
Series dual-electrode detector for liquid chromatography/electrochemistry
复制标题
液相色谱/电化学系列双电极检测器
DOI：
10.1021/ac00240a019
复制
发表时间：
1982
影响因子：
7.4
通讯作者：
P. Kissinger
中科院分区：
文献类型：
--
作者：
D. A. Roston;P. Kissinger
通过使用电极相对于流动轴串联定向的双电极检测器，来自上游检测器的氧化产物通过在下游检测器处的还原而被检测。利用氧化还原模式可以在液相色谱/电化学的三个方面进行改进：选择性、峰识别和极端电位下的高增益检测。上述改进在两个相关分析问题的背景下得到证明：商业饮料中酚类成分的测定和尿液中镇痛剂对乙酰氨基酚的代谢物的测定。还包括有关确定在下游检测器处转化的上游产物分数大小（所谓的收集效率）时重要因素的讨论。液相色谱与电化学相结合 (LCEC) 已成为痕量有机物测定的成熟技术 (1)。该技术结合了高选择性、低检测限和低成本的优点。电化学检测的创新方法涉及使用双电极换能器。多项研究报道了液相色谱双电极检测的使用 (2-6)。在每种情况下，电极相对于流动轴的方向都是图 1 所示的三种配置之一，我们将其称为并联相邻配置、串联配置和并联相对配置。芬恩等人。探索了平行相对双电极检测改善血浆中儿茶酚胺检测的可能性 (2)。 Blank 采用了一系列配置检测器进行双电位监测，以提高特异性 (3)。两个电极均以氧化模式使用。 Roston 和 Kissinger 使用平行相邻检测器进行双电位监测，以帮助识别商业饮料中的酚类成分 (4)。 Schieffer 报道了串联库仑电流检测器的设计和使用 (5)。通过“上游”库仑电池去除容易氧化的成分被证明可以提高下游检测器的选择性。串联双电极检测器的潜在有用的检测方案涉及在下游检测器处检测来自上游检测器的产物。当以这种方式使用时，串联检测器类似于经过充分研究的环盘电极，其中来自盘的产物
By utilization of a dual-electrode detector with the electrodes oriented In series with respect to the flow axis, oxidation products from the upstream detector are detected by reduction at the downstream detector. Exploiting the oxldatlve-reductlve mode allows Improvements In three aspects of liquid chromatography/electrochemlstry: selectivity, peak Identifi-cation, and high gain detection at extreme potentials. The above Improvements are demonstrated In the context of two pertinent analytical problems: the determination of phenolic constituents In commercial beverages and the determination of the metabolites of the analgesic acetaminophen In urine. Also Included Is a discussion concerning the factors that are Important In determining the magnitude of the fraction of up-stream products that are converted at the downstream de-tector (the so-called collection efficiency).Liquid chromatography combined with electrochemistry (LCEC) has become a well-established technique for traceorganic determinations (1). The technique couples the advantages of high selectivity, low detection limits, and low cost. An innovative approach to electrochemical detection involves the use of dual-electrodetransducers. Several studies have reported the use of dual-electrode detection for liquid chromatography (2-6). In each case, the orientation of the elec-trodes with respect to the flow axis was one of the three configurations shown in Figure 1, which we have termed the parallel-adjacent, series, and parallel-opposed configurations. Fenn et al. explored the possibility of parallel-opposed dual-electrode detection to improve detection of catechol-amines in blood plasma (2). Blank employed a series con-figuration detector for dual-potential monitoring to improve specificity (3). Both electrodes were used in an oxidative mode. Roston and Kissinger performeddual-potential mon-itoring with a parallel-adjacent detector to aid in the iden-tification of phenolic constituents in commercial beverages (4). The design and use of a series coulometric-amperometric detector was reported by Schieffer (5). Removal of easily oxidized components by the “upstream” coulometric cell was shown to increase selectivity at the downstream detector. A potentially useful detection scheme for the series dual-electrode detector involves the detectionof products from the upstream detector at the downstream detector. When used in this manner, the series detector is analogous to the wellstudied ring-disk electrode in which products from the disk