Voltammetric studies of lead at a 1-(2-pyridylazo)-2-naphthol modified screen-printed carbon electrode and its trace determination in water by stripping voltammetry
Voltammetric studies of lead at a 1-(2-pyridylazo)-2-naphthol modified screen-printed carbon electrode and its trace determination in water by stripping voltammetry
复制标题
DOI：
10.1016/s0003-2670(00)01294-0
复制
发表时间：
2001-03-08
影响因子：
6.2
通讯作者：
Cowell, DC
中科院分区：
文献类型：
--
作者：
Honeychurch, KC;Hart, JP;Cowell, DC
研究了一次性1-（2-吡啶偶氮）-2-萘酚（PAN）滴涂修饰丝网印刷碳电极（PAN-SPCE）测定痕量铅的方法。铅离子（Pb 2+）从氨缓冲液中积累，在PAN-SPCE表面形成的化学络合物在开路。然后将所得的具有络合的Pb 2+的SPCE转移到0.1 M HCl中并进行差分脉冲阳极溶出伏安法。条件进行了优化的pH值和浓度的积累介质，预浓缩时间和滴涂PAN的质量。一个5分钟的预浓缩时间导致15 ng ml（-1）的检测限。发现校准图为双峰，线性范围为0 - 700 ng ml（-1）和700-5000 ng ml（-1）Pb 2+。主要金属干扰是铜，但通过在累积步骤之前向氨缓冲液中加入碘化物成功克服了该问题。该方法进行了评价，通过进行铅测定加标饮用水样品; Pb 2+的回收率为92.5%，变异系数被认为是4.4%（n = 5），使用单独的PAN-SPCE为每个测定。因此，性能数据表明，该方法在本研究中检查的浓度下是可靠的;此外，该数据与已发表方法获得的数据相比具有优势。(C)2001 Elsevier Science B. V.保留所有权利。
A method for the trace determination of Pb2+, using a disposable 1-(2-pyridylazo)-2-naphthol (PAN) drop-coated modified screen-printed carbon electrode (PAN-SPCE), has been developed. Lead ions (Pb2+) are accumulated from ammonia buffer, on the PAN-SPCE surface by the formation of a chemical complex at open circuit. The resulting SPCE with complexed Pb2+ is then transferred to 0.1 M HCl and subjected to differential pulse anodic stripping voltammetry. Conditions were optimised with respect to the pH and concentration of the accumulation medium, preconcentration time and the mass of drop-coated PAN. A 5 min preconcentration time resulted in a limit of detection of 15 ng ml(-1). The calibration plot was found bimodal with linear ranges between 0 and 700 ng ml(-1) and 700-5000 ng ml(-1) Pb2+. The principal metal interference was copper, but this problem was successfully overcome by the addition of iodide to the ammonia buffer prior to the accumulation step. The method was evaluated by carrying out lead determinations on spiked potable water samples; the recovery of Pb2+ was 92.5% and the coefficient of variation was found to be 4.4% (n = 5) using a separate PAN-SPCE for each determination. Therefore, the performance data suggests that the method is reliable at the concentrations examined in this study; in addition, the data compared favorably with that obtained by a published method. (C) 2001 Elsevier Science B.V. All rights reserved.