Determination of Arsenic in Traditional Chinese Medicines Honeysuckle and Panpax Notoginseng by Chronopotentiometric Stripping Analysis

A method for the determination of arsenic in traditional Chinese medicines by chronopotentiometric stripping analysis was proposed with gold-plated glassy carbon electrode as working electrode.A sensitive 2ndary differential potentiometric stripping peak of As was obtained at the potential of +0.13 V (vs.SCE),when accumulation potential taken was -0.40 V and 2.5 mol·L-1 HNO3 was used as base solution.Linear relationship between values of the peak height and mass concentration of arsenic was kept in the range of 2.0-10.0 μg·L-1.Detection limit (3S/N) of the method was found as 1.0 μg·L-1.The proposed method was used in the analysis of samples of honeysuckle and panpax notoginseng,giving values of recovery of 96.7% and 107.1% respectively.