title: On-line preconcentration and determination of cadmium in honey using knotted reactor coupled to flow injection-flame atomic absorption spectrometry.
abstract: An on-line cadmium preconcentration and determination system implemented with flame atomic absorption spectrometry (FAAS) associated with flow injection was studied. Cadmium was retained as Cd-2-(5-bromo-2-pyridylazo)-5-diethylaminophenol Cd-(5-Br-PADAP) complex, pH 9.3. The Cd complex was removed from the knotted reactor (KR) with ethanol. A total enhancement factor of 140 was obtained with respect to FAAS (40 for KR and 3.5 due to the use of ethanol) with preconcentration time of 120 s. The detection limit value for preconcentration of 1 g sample was 0.5 ng/g. The repeatability for 10 replicate determinations at 5.0 ng/g Cd level was 3.5% relative standard deviation, calculated from peak heights obtained. The calibration graph using the preconcentration system for Cd was linear with a correlation coefficient of 0.9990 at levels near the detection limits to at least 2000 ng/g. The method was successfully applied to determination of total Cd in honey samples.
authors.affiliation: National University of San Luis, Chacabuco and Pedernera, Department of Analytical Chemistry, Faculty of Chemistry, Biochemistry and Pharmacy, San Luis, Argentina.
authors.forename: Orsi Ricardo
authors.initials: OR
authors.lastname: Fernández
authors.forename: Rodolfo G
authors.initials: RG
authors.lastname: Wuilloud
authors.forename: Jorgelina C A
authors.initials: JC
authors.lastname: de Wuilloud
authors.forename: Roberto A
authors.initials: RA
authors.lastname: Olsina
authors.forename: Luis D
authors.initials: LD
authors.lastname: Martinez
mesh_terms: D000818:Animals; D001516:Bees / Q000737:chemistry; D002021:Buffers; D002104:Cadmium / Q000032:analysis*; D017022:Flow Injection Analysis; D006722:Honey / Q000032:analysis*; D007202:Indicators and Reagents; D008670:Metals / Q000032:analysis; D009862:Online Systems; D015203:Reproducibility of Results; D013054:Spectrophotometry, Atomic
chemical_list: D002021:Buffers; D007202:Indicators and Reagents; D008670:Metals; D002104:Cadmium