Determination of Chromium(Ⅵ) Released from Ceramic Jewelry by Reversed-Phase HPLC

The reversed-phase high performance liquid chromatography (RP-HPLC) combined with pre-column derivatization was used to determine chromium(Ⅵ) released from ceramic jewelry. The ceramic jewelry sample was extracted by artificial sweat. Chromium(Ⅵ) in the extraction was derivatized with 1,5-diphenylcarbazide under acidic condition. The derivative was separated using Waters SunFire ODS C18 column as stationary phase and a mixture of acetone and KH2PO4 solution of 10 mmol·L-1 with pH 2.5 as mobile phase for gradient elution. Absorbance at 540 nm was measured. The linear relationship between the peak area and the mass concentration of chromium(Ⅵ) was found in the range of 5.0-200.0 μg·L-1, with correlation coefficient of 0. 999 1 and detection limit (3S/N) of 0.037 μg·L-1. Tests for recovery were made by standard addition, giving recovery rates in the range of 97%-101% and RSD (n=7) in the range of 1.9%-3.2%.