Alves Vanessa N, Borges Simone S O, Neto Waldomiro B, Coelho Nívia M M
Instituto de Química, Universidade Federal de Uberlândia, 38400-902 Uberlândia, MG, Brazil.
J Autom Methods Manag Chem. 2011;2011:464102. doi: 10.1155/2011/464102. Epub 2011 Oct 13.
In this study, a method for the determination of low concentrations of lead in beer samples using solid-phase extraction with a flow injection analysis system and detection by flame atomic absorption spectrometry (FAAS) was developed. Moringa oleifera seeds were used as a biosorbent material. Chemical and flow variables of the online preconcentration system, such as sample pH, preconcentration flow rate, eluent flow rate, eluent concentration, particle size, and sorbent mass, were studied. The optimum extraction conditions were obtained using a sample pH of 6.0, sample flow rate of 6.0 mL min(-1), 63.0 mg of sorbent mass, and 2.0 mol L(-1) HNO(3) at a flow rate of 2.0 mL min(-1) as the eluent. With the optimized conditions, the preconcentration factor, precision, detection limit, consumption index, and sample throughput were estimated as 93, 0.3% (10.0 μg L(-1), n = 7), 7.5 μg L(-1), 0.11 mL, and 23 samples per hour, respectively. The method developed was successfully applied to beer samples and recovery tests, with recovery ranging from 80% to 100%.
在本研究中，开发了一种使用流动注射分析系统进行固相萃取并通过火焰原子吸收光谱法（FAAS）检测来测定啤酒样品中低浓度铅的方法。辣木籽被用作生物吸附材料。研究了在线预浓缩系统的化学和流动变量，如样品pH值、预浓缩流速、洗脱液流速、洗脱液浓度、粒径和吸附剂质量。使用样品pH值为6.0、样品流速为6.0 mL min⁻¹、吸附剂质量为63.0 mg以及2.0 mol L⁻¹ HNO₃以2.0 mL min⁻¹的流速作为洗脱液，获得了最佳萃取条件。在优化条件下，预浓缩因子、精密度、检测限、消耗指数和样品通量分别估计为93、0.3%（10.0 μg L⁻¹，n = 7）、7.5 μg L⁻¹、0.11 mL和每小时23个样品。所开发的方法成功应用于啤酒样品和回收率测试，回收率范围为80%至100%。
