title: Screening of cadmium and lead in potentially contaminated waters using a spectrophotometric sequential injection lab-on-valve methodology.
abstract: The present work describes the development of a µSI-LOV method for the simultaneous screening of cadmium and lead in potentially contaminated water samples. To attain the biparametric determination, dithizone was chosen as the spectrophotometric reagent as it forms a colored complex with both metal ions, at different pH conditions. The cadmium determination was attained in strong alkaline conditions (pH≈12); the lead determination was calculated by the difference with the determination of both metals in mild alkaline conditions (pH≈8). The colored complex was measured at 550 nm and the method presented a LOD of 34 μg L(-1) for cadmium and 56 μg L(-1) for lead, with a sample consumption of 20 µL per assay and a determination rate of 55 h(-1). The results obtained were in agreement with those obtained by FAAS. The developed method was efficiently applied to the screening of cadmium and lead in marine port waters.
authors.affiliation: CBQF - Centro de Biotecnologia e Química Fina - Laboratório Associado, Escola Superior de Biotecnologia, Universidade Católica Portuguesa/Porto, Rua Arquiteto Lobão Vital, Apartado 2511, 4202-401 Porto, Portugal.
authors.forename: Inês C
authors.initials: IC
authors.lastname: Santos
authors.affiliation: CBQF - Centro de Biotecnologia e Química Fina - Laboratório Associado, Escola Superior de Biotecnologia, Universidade Católica Portuguesa/Porto, Rua Arquiteto Lobão Vital, Apartado 2511, 4202-401 Porto, Portugal; Laboratory of Hydrobiology, Institute of Biomedical Sciences Abel Salazar (ICBAS) and Institute of Marine Research (CIIMAR), Universidade do Porto, Rua de Jorge Viterbo Ferreira no. 228, 4050-313 Porto, Portugal.
authors.forename: Raquel B R
authors.initials: RBR
authors.lastname: Mesquita
authors.affiliation: CBQF - Centro de Biotecnologia e Química Fina - Laboratório Associado, Escola Superior de Biotecnologia, Universidade Católica Portuguesa/Porto, Rua Arquiteto Lobão Vital, Apartado 2511, 4202-401 Porto, Portugal. Electronic address: arangel@porto.ucp.pt.
authors.forename: António O S S
authors.initials: AOSS
authors.lastname: Rangel
mesh_terms: D002104:Cadmium / Q000032:analysis* / Q000737:chemistry; D004230:Dithizone / Q000737:chemistry; D007854:Lead / Q000032:analysis* / Q000737:chemistry; D012623:Seawater / Q000032:analysis; D013053:Spectrophotometry / Q000379:methods; D014874:Water Pollutants, Chemical / Q000032:analysis* / Q000737:chemistry
chemical_list: D014874:Water Pollutants, Chemical; D002104:Cadmium; D007854:Lead; D004230:Dithizone
keywords: Biparametric determination; Cadmium; Lead; Marine waters; Metals screening; Spectrophotometry; µSI-LOV