Vanloot Pierre, Branger Catherine, Margaillan André, Brach-Papa Christophe, Boudenne Jean-Luc, Coulomb Bruno
Laboratoire de Chimie et Environnement (FRE 2704), Université de Provence - Case 29, 3 place Victor Hugo, 13331 Marseille cedex 3, France.
Anal Bioanal Chem. 2007 Nov;389(5):1595-602. doi: 10.1007/s00216-007-1538-y. Epub 2007 Sep 2.
A new analytical method was developed for on-line monitoring of residual coagulants (aluminium and iron salts) in potable water. The determination was based on a sequential procedure coupling an extraction/enrichment step of the analytes onto a modified resin and a spectrophotometric measurement of a surfactant-sensitized binary complex formed between eluted analytes and Chrome Azurol S. The optimization of the solid phase extraction was performed using factorial design and a Doehlert matrix considering six variables: sample percolation rate, sample metal concentration, flow-through sample volume (all three directly linked to the extraction step), elution flow rate, concentration and volume of eluent (all three directly linked to the elution step). A specific reagent was elaborated for sensitive and specific spectrophotometric determination of Al(III) and Fe(III), by optimizing surfactant and ligand concentrations and buffer composition. The whole procedure was automated by a multisyringe flow injection analysis (MSFIA) system. Detection limits of 4.9 and 5.6 microg L(-1) were obtained for Al(III) and Fe(III) determination , respectively, and the linear calibration graph up to 300 microg L(-1) (both for Al(III) and Fe(III)) was well adapted to the monitoring of drinking water quality. The system was successfully applied to the on-site determination of Al(III) and Fe(III) at the outlet of two water treatment units during two periods of the year (winter and summer conditions).
开发了一种新的分析方法，用于在线监测饮用水中的残留凝结剂（铝盐和铁盐）。该测定基于一个连续过程，该过程将分析物的萃取/富集步骤与修饰树脂相结合，并对洗脱的分析物与铬天青S形成的表面活性剂敏化二元络合物进行分光光度测量。使用析因设计和Doehlert矩阵对固相萃取进行优化，考虑六个变量：样品渗滤速率、样品金属浓度、流通样品体积（这三个变量都与萃取步骤直接相关）、洗脱流速、洗脱剂浓度和体积（这三个变量都与洗脱步骤直接相关）。通过优化表面活性剂和配体浓度以及缓冲液组成，制备了一种用于灵敏且特异分光光度法测定Al(III)和Fe(III)的特定试剂。整个过程由多注射器流动注射分析（MSFIA）系统自动化。Al(III)和Fe(III)测定的检测限分别为4.9和5.6 μg L⁻¹，高达300 μg L⁻¹的线性校准曲线（Al(III)和Fe(III)均适用）非常适合饮用水质量监测。该系统已成功应用于一年中两个时期（冬季和夏季条件）两个水处理单元出口处Al(III)和Fe(III)的现场测定。
