Salonia J A, Wuilloud R G, Gásquez J A, Olsina R A, Martinez L D
Area de Química Analítica, Facultad de Química, Bioquímica y Farmacia, Universidad Nacional de San Luis, Chacabuco y Pedernera, San Luis, Argentina.
Fresenius J Anal Chem. 2000 Aug;367(7):653-7. doi: 10.1007/s002160000428.
An on-line zinc preconcentration and determination system implemented with inductively coupled plasma atomic emission spectrometry (ICP-AES) associated with flow injection (FI) was studied. The zinc was retained as zinc-2-(5-bromo-2-pyridylazo)-5-diethylaminophenol (Zn-(5-Br-PADAP)) complex at pH 9.2. The zinc complex was removed from the knotted reactor (KR) with 30% v/v nitric acid. An enrichment factor of 42 was obtained for the KR system with respect to ICP-AES using pneumatic nebulization. The detection limit for the preconcentration of 10 mL of aqueous solution was 0.09 microg/L. The precision for 10 replicate determinations at the 5 microg/L Zn level was 2.3% relative standard deviation (RSD), calculated with the peak heights obtained. The calibration graph using the preconcentration system for zinc was linear with a correlation coefficient of 0.9997 at levels near the detection limits up to at least 100 microg/L. The method was succesfully applied to the determination of zinc in river water samples.
研究了一种与流动注射（FI）联用的电感耦合等离子体原子发射光谱法（ICP-AES）实现的在线锌预富集和测定系统。锌在pH 9.2条件下以锌-2-（5-溴-2-吡啶偶氮）-5-二乙氨基苯酚（Zn-(5-Br-PADAP)）络合物的形式被保留。锌络合物用30%（v/v）硝酸从打结反应器（KR）中洗脱。相对于使用气动雾化的ICP-AES，KR系统的富集因子为42。对10 mL水溶液进行预富集的检测限为0.09 μg/L。在5 μg/L锌水平下进行10次重复测定的精密度为2.3%相对标准偏差（RSD），以获得的峰高计算。使用锌预富集系统的校准曲线在接近检测限直至至少100 μg/L的水平范围内呈线性，相关系数为0.9997。该方法成功应用于河水样品中锌的测定。
