title: Determination of cadmium in herbs by SFODME with ETAAS detection.
abstract: A method for the determination of cadmium in herb samples based on solidified floating organic drop microextraction (SFODME) using 1-(2-Pyridylazo)-2-naphthol (PAN) as a chelating reagent and detection by electrothermal atomic absorption spectrometry (ETAAS) was developed in the present work. The effects of pH, extraction solvent, extraction time, stirring rate, and extraction temperature were investigated. Under the optimized conditions, the calibration graph was linear in the range of 0.017-3.0μgL-1, with a detection limit (LOD) of 0.0052μgL-1. The relative standard deviation (%RSD) for 6 replicate measurements of 1.0μgL-1cadmium was ±2.67%. The method was applied to the analysis of 10 types of Thai herb samples. Percentage recoveries were in the range 94.5-110.2%. It was found that cadmium concentrations in all Thai herb samples were less than the maximum residue level.
authors.affiliation: Department of Chemistry, Research Center for Academic Excellence in Petroleum, Petrochemical and Advanced Materials, Faculty of Science, Naresuan University, Phitsanulok 65000, Thailand.
authors.forename: Arnon
authors.initials: A
authors.lastname: Thongsaw
authors.affiliation: Department of Chemistry, Research Center for Academic Excellence in Petroleum, Petrochemical and Advanced Materials, Faculty of Science, Naresuan University, Phitsanulok 65000, Thailand. Electronic address: wipharatc@nu.ac.th.
authors.forename: Wipharat Chuachuad
authors.initials: WC
authors.lastname: Chaiyasith
authors.affiliation: Department of Chemistry, Research Center for Academic Excellence in Petroleum, Petrochemical and Advanced Materials, Faculty of Science, Naresuan University, Phitsanulok 65000, Thailand.
authors.forename: Ratana
authors.initials: R
authors.lastname: Sananmuang
authors.affiliation: Department of Chemistry, Research Center for Academic Excellence in Petroleum, Petrochemical and Advanced Materials, Faculty of Science, Naresuan University, Phitsanulok 65000, Thailand.
authors.forename: Gareth M
authors.initials: GM
authors.lastname: Ross
authors.affiliation: Department of Chemistry, 431 Merrill Science, Amherst College, Amherst, MA 01002-5000, USA.
authors.forename: Richmond J
authors.initials: RJ
authors.lastname: Ampiah-Bonney
mesh_terms: D002104:Cadmium / Q000032:analysis*; D009284:Naphthols; D010944:Plants / Q000737:chemistry*; D013054:Spectrophotometry, Atomic / Q000379:methods; D013696:Temperature; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D009284:Naphthols; D014874:Water Pollutants, Chemical; D002104:Cadmium; C041728:1-(2-pyridylazo)-2-naphthol
keywords: 1-(2-Pyridylazo)-2-naphthol (PAN); Cadmium; Electrothermal atomic absorption spectrometry; Herbs; Solidified floating organic drop microextraction