title: Determination of trace lead in water samples by continuous flow microextraction combined with graphite furnace atomic absorption spectrometry.
abstract: A new method of continuous flow microextraction (CFME) combined with graphite furnace atomic absorption spectrometry (GFAAS) was proposed for the determination of trace lead in water samples. A drop of 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone (PMBP) dissolved in benzene is injected into a glass chamber by a microsyringe and held at the outlet tip of a PTFE connecting tube, the sample solution flows right through the tube and the glass chamber, the solvent drop interacts continuously with the sample solution, and the analyte was extracted into the drop and concentrated. After extracting for a period of time, the drop was retracted into the microsyringe and directly injected into graphite furnace for determination of Pb. Several factors affecting the extraction efficiency, such as solution pH, sample flow rate, drop volume and extraction time, were optimized. Under the optimized conditions, a concentration factor of 45 was achieved, and the detection limits for Pb were 12 pg mL(-1). The relative standard deviation for six replicate analyses of 10 ng mL(-1) Pb was 6.8%. The proposed method was applied to determine of trace Pb in water samples with satisfactory results.
authors.affiliation: Key Laboratory of Pesticide & Chemical Biology of Ministry of Education, College of Chemistry, Central China Normal University, Wuhan 430079, PR China.
authors.forename: Jing
authors.initials: J
authors.lastname: Cao
authors.forename: Pei
authors.initials: P
authors.lastname: Liang
authors.forename: Rui
authors.initials: R
authors.lastname: Liu
mesh_terms: D007854:Lead / Q000032:analysis*; D012015:Reference Standards; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013054:Spectrophotometry, Atomic / Q000379:methods*; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D014874:Water Pollutants, Chemical; D007854:Lead