title: Simultaneous separation and determination of six arsenic species in rice by anion-exchange chromatography with inductively coupled plasma mass spectrometry.
abstract: The simultaneous separation and determination of arsenite As(III), arsenate As(V), monomethylarsonic acid (MMA), dimethylarsinic acid (DMA), arsenobetaine (AsB), and arsenocholine (AsC) in rice samples have been carried out in one single anion-exchange column run by high-performance liquid chromatography with inductively coupled plasma mass spectrometry. To estimate the effect of variables on arsenic (As) speciation, the chromatographic conditions including type of competing anion, ionic strength, pH of elution buffer, and flow rate of mobile phase have been investigated by a univariate approach. Under the optimum chromatographic conditions, baseline separation of six As species has been achieved within 10 min by gradient elution program using 4 mM NH4 HCO3 at pH 8.6 as mobile phase A and 4 mM NH4 HCO3 , 40 mM NH4 NO3 at pH 8.6 as mobile phase B. The method detection limits for As(III), As(V), MMA, DMA, AsB, and AsC were 0.4, 0.9, 0.2, 0.4, 0.5, and 0.3 μg/kg, respectively. The proposed method has been applied to separation and quantification of As species in real rice samples collected from Hunan Province, China. The main As species detected in all samples were As(III), As(V) and DMA, with inorganic As accounting for over 80% of total As in these samples.
authors.affiliation: College of Chemistry & Chemical Engineering, Central South University, Changsha, China.
authors.forename: Li
authors.initials: L
authors.lastname: Ma
authors.affiliation: College of Chemistry & Chemical Engineering, Central South University, Changsha, China.|Center for Environment and Water Resources, Central South University, Changsha, China.
authors.forename: Zhaoguang
authors.initials: Z
authors.lastname: Yang
authors.affiliation: Institute of Clinical Pharmacology, Xiangya Hospital, Central South University, Changsha, China.
authors.forename: Jie
authors.initials: J
authors.lastname: Tang
authors.affiliation: College of Chemistry & Chemical Engineering, Central South University, Changsha, China.
authors.forename: Lin
authors.initials: L
authors.lastname: Wang
mesh_terms: D001151:Arsenic / Q000032:analysis*; D002851:Chromatography, High Pressure Liquid; D002852:Chromatography, Ion Exchange; D013058:Mass Spectrometry; D012275:Oryza / Q000737:chemistry*
chemical_list: D001151:Arsenic
keywords: Anion-exchange column; Arsenic; Gradient elution; Rice; Speciation