Evaluation of HPLC Systems for the Separation and Quantification of Arsenic Compounds From Apple Extracts

Several different high performance liquid chromatography (HPLC) systems were evaluated for the applicability for the determination of trace level arsenic compounds from extracts of freeze-dried apple samples. Various gradients using ion-pair reversed-phase HPLC were explored. Gradient anion-exchange HPLC, as well as a simple isocratic system, were also evaluated in this study. Two extraction procedures were used. Simple sonication by a common laboratory ultrasonic cleaner using a 50/50 (v/v) water/methanol solvent mixture and a two step procedure using initial overnight treatment with α-amylase enzyme followed by sonication with a 60/40 (v/v) acetonitrile/water solvent mixture were evaluated. Inductively Coupled Plasma-Mass Spectrometric (ICP-MS) detection was used to measure the arsenic compounds contained within the apple extracts. The three most abundant arsenic compounds found in the extracts were arsenite (As III), arsenate (As V) and dimethylarsinic acid (DMAA).