Alves Vanessa N, Borges Simone S O, Coelho Nivia M M
Instituto de Química, Universidade Federal de Uberlândia, Uberlândia 38400-902, MG, Brazil.
Int J Anal Chem. 2011;2011:765746. doi: 10.1155/2011/765746. Epub 2011 Jul 7.
This paper reports a method for the determination of zinc in Brazilian sugar cane spirit, (cachaça in Portuguese), using solid-phase extraction with a flow injection analysis system and detection by FAAS. The sorbent material used was activated carbon obtained from Moringa oleifera husks. Flow and chemical variables of the proposed system were optimized through multivariate designs. The factors selected were sorbent mass, sample pH, sample flow rate, and eluent concentration. The optimum extraction conditions were obtained using a sample pH of 4.0, a sample flow rate of 6.0 mL min(-1), 30.0 mg of sorbent mass, and 1.0 mol L(-1) HNO(3) as the eluent at a flow rate of 4.0 mL min(-1). The limit of detection for zinc was 1.9 μg L(-1), and the precision was below 0.82% (20.0 μg L(-1), n = 7). The analytical curve was linear from 2 to 50 μg L(-1), with a correlation coefficient of 0.9996. The method developed was successfully applied to spiked Brazilian sugar cane spirit, and accuracy was assessed through recovery tests, with results ranging from 83% to 100%.
本文报道了一种采用流动注射分析系统固相萃取结合火焰原子吸收光谱法（FAAS）检测巴西甘蔗酒（葡萄牙语为cachaça）中锌含量的方法。所用吸附剂材料是从辣木壳中获得的活性炭。通过多变量设计对所提出系统的流量和化学变量进行了优化。所选择的因素包括吸附剂质量、样品pH值、样品流速和洗脱液浓度。最佳萃取条件为：样品pH值为4.0，样品流速为6.0 mL min⁻¹，吸附剂质量为30.0 mg，以1.0 mol L⁻¹ HNO₃作为洗脱液，流速为4.0 mL min⁻¹。锌的检测限为1.9 μg L⁻¹，精密度低于0.82%（20.0 μg L⁻¹，n = 7）。分析曲线在2至50 μg L⁻¹范围内呈线性，相关系数为0.9996。所开发的方法成功应用于加标巴西甘蔗酒，并通过回收率测试评估了准确性，结果范围为83%至100%。
