Speciation analysis of arsenic in fruits and vegetables by high performance liquid chromatography-hydride generation-atomic fluorescence spectrometry with ultrasonic extraction

A method was developed for simultaneously determination of four arsenic speciation including trivalent arsenic (As (III)), pentavalent arsenic (As (V)), monomethylarsinic acid (MMA) and dimethylarsinic acid (DMA) in fruits and vegetables. Arsenic speciation in samples were extracted with methanol/water (50/50, v/v) after samples were dried at 105°C, and then detected by high performance liquid chromatography-hydride generation atomic fluorescence spectrometry (HPLC-HG-AFS). The recoveries of four arsenic speciation were 81.7%~103.9% with RSD of 0.88%~5.03%, and detection limits were 0.8-2.0 μg/kg. This indicates that the developed method has good accuracy and high sensitivity. The method was then applied to detect eleven types of fruits and vegetables samples randomly purchased from supermarkets. The analytical results showed that the main arsenic speciation were As (III) and As (V) in vegetables and As (III) in fruits. The concentrations of As (III) in vegetables were obviously higher than those in fruits.