title: Feasibility of microwave-induced combustion for trace element determination in Engraulis anchoita by ICP-MS.
abstract: A method based on microwave-induced combustion (MIC) was developed for fish (Engraulis anchoita) digestion and subsequent determination of As, Cd, Co, Cr, Cu, Fe, Mn, Mo, Ni, Se, and Zn by inductively coupled plasma mass spectrometry (ICP-MS). A reflux step (5 min) was applied to improve absorption and recovery of analytes. Nitric acid was investigated as absorbing solution and suitable results were achieved using 5 mol L⁻¹ HNO₃. Microwave-assisted digestion in closed vessels using concentrated HNO₃ was also evaluated for comparison of results. Both sample preparation methods were considered suitable for sample digestion but MIC was preferable not only because diluted HNO3 can be used as absorbing solution but also because it provides higher efficiency of digestion and also better limits of detection. Accuracy was evaluated by the analysis of certified reference materials (DORM-2 and TORT-2) after MIC digestion with subsequent determination by ICP-MS. Agreement with certified values was better than 94%.
authors.affiliation: Escola de Química e Alimentos, Universidade Federal do Rio Grande, 96203-900 Rio Grande, RS, Brazil; Departamento de Química, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil.
authors.forename: Juliana V
authors.initials: JV
authors.lastname: Maciel
authors.forename: Camila L
authors.initials: CL
authors.lastname: Knorr
authors.forename: Erico M M
authors.initials: EM
authors.lastname: Flores
authors.forename: Edson I
authors.initials: EI
authors.lastname: Müller
authors.forename: Marcia F
authors.initials: MF
authors.lastname: Mesko
authors.forename: Ednei G
authors.initials: EG
authors.lastname: Primel
authors.forename: Fabio A
authors.initials: FA
authors.lastname: Duarte
mesh_terms: D053000:Analytic Sample Preparation Methods; D000818:Animals; D001267:Atlantic Ocean; D001938:Brazil; D005240:Feasibility Studies; D005399:Fishes; D005504:Food Analysis / Q000379:methods; D005506:Food Contamination; D005513:Food Inspection / Q000379:methods; D006801:Humans; D006868:Hydrolysis / Q000528:radiation effects; D007202:Indicators and Reagents / Q000737:chemistry; D057230:Limit of Detection; D019216:Metals, Heavy / Q000032:analysis* / Q000737:chemistry; D008872:Microwaves; D017942:Nitric Acid / Q000737:chemistry; D009753:Nutritive Value; D015203:Reproducibility of Results; D017747:Seafood / Q000032:analysis* / Q000528:radiation effects; D012995:Solubility; D013054:Spectrophotometry, Atomic; D014131:Trace Elements / Q000032:analysis* / Q000737:chemistry
chemical_list: D007202:Indicators and Reagents; D019216:Metals, Heavy; D014131:Trace Elements; D017942:Nitric Acid
keywords: Engraulis anchoita; Inductively coupled plasma mass spectrometry; Microwave-induced combustion; Trace element determination