title: [Study on the determination of trace Cu and Mn in foodstuff preconcentration by precipitate flotation and FAAS].
abstract: In the present paper, the use of 8-hydroxyquinoline(oxine, HQ) complexs in precipitate flotation to separate and preconcentrate Cu and Mn, using SDBS as collector, followed by AAS spectrophotometric determination is proposed. The optimum conditions of precipitate flotation were studied. The effects of several parameters of flotation processes condition on single metal ions precipitation-flotation and multi-metal ions coprecipitation-flotation of Cu and Mn at pH 9 were investigated. The experimental results show that the flotation rate of Cu is supreme with pH 9. Under the condition of pH 9 and changing the ratio of concentration, when Mn/Cu> or =8, the recovery rate of Cu is less than 90%. This method is simple, rapid, accurate, sensitive and precise and avoids using the virulent organic solvent. The linear range of Cu is 0.5-5.0 microg x mL(-1) with the correlative coefficient of 0.9996, detection limit of this method was found to be 1.59 x 10(-3) microg x mL(-1), the linear range of Mn is 0.5-5.0 microg x mL(-1) with the correlative coefficient of 0.9987, and the detection limit of this method was found to be 3.52 x 10(-3) microg x mL(-1). The method was applied to the determination of Cu and Mn in foodstuff, and the recovery is 87.6%-100.7%. The result was satisfactory.
authors.affiliation: Department of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang 212013, China.
authors.forename: Chun-xiang
authors.initials: CX
authors.lastname: Li
authors.forename: Ting-yu
authors.initials: TY
authors.lastname: Chen
authors.forename: Yong-sheng
authors.initials: YS
authors.lastname: Yan
mesh_terms: D003300:Copper / Q000032:analysis*; D005504:Food Analysis; D008345:Manganese / Q000032:analysis*; D013054:Spectrophotometry, Atomic / Q000295:instrumentation / Q000379:methods*
chemical_list: D008345:Manganese; D003300:Copper