title: A simple and sensitive flow-injection on-line preconcentration coupled with hydride generation atomic fluorescence spectrometry for the determination of ultra-trace lead in water, wine, and rice.
abstract: A simple and sensitive flow-injection on-line separation and preconcentration system coupled to hydride generation atomic fluorescence spectrometry (HG-AFS) was developed for ultra-trace lead determination in water, wine, and rice samples, with the salient advantages of its minimization of transition-metal interferences and tolerance to an ethanol matrix. A lead hydroxide precipitate was achieved by the on-line merging of a sample and an ammonium buffer solution and collected onto the inner walls of a knotted reactor (KR). Removal of the residual solution from KR was achieved by air flow, and dissolution of the precipitate was carried out by using 0.2 mol l(-1) HCl. With a sample consumption of 11.7 ml, an enhancement factor of 16 was obtained at a sample throughput of 30 h(-1). The limit of detection (3s) was 16 ng l(-1) and the precision (RSD) for 1.0 microg l(-1) Pb was 3.4%.
authors: School of Chemistry and Chemical Engineering, Key Laboratory of MOE for Life Science & State Key Laboratory of Coordination Chemistry, Analytical Center, Nanjing University, Nanjing, China.
authors: Hong
authors: H
authors: Wu
authors: Yan
authors: Y
authors: Jin
authors: Mingbiao
authors: M
authors: Luo
authors: Shuping
authors: S
authors: Bi
mesh_terms: D000431:Ethanol; D017022:Flow Injection Analysis / Q000295:instrumentation / Q000379:methods*; D006863:Hydrogen-Ion Concentration; D007854:Lead / Q000032:analysis*; D009862:Online Systems / Q000295:instrumentation; D012275:Oryza / Q000737:chemistry*; D012680:Sensitivity and Specificity; D013050:Spectrometry, Fluorescence / Q000295:instrumentation / Q000379:methods*; D013054:Spectrophotometry, Atomic / Q000295:instrumentation / Q000379:methods*; D014867:Water / Q000737:chemistry*; D014920:Wine / Q000032:analysis*
chemical_list: D014867:Water; D007854:Lead; D000431:Ethanol