[Determination of cinnabar in zijinhong capsules by high performance liquid chromatography]

A high performance liquid chromatographic method was established for the determination of cinnabar in Zijinhong capsules using diethyldithiocarbamate (DEDTC) chelate. A Waters X-Terra C18 column was used with a mixture of methanol-0.01 mol/L Na2HPO4 (pH 7.5) (containing 0.01% DEDTC) (73:27, V/V) as the mobile phase and a detector set at 270 nm. The calibration curve was linear (r = 0. 999 6) in the range of 10.1 mg/L - 100.9 mg/L of Hg2+. The recoveries were 97.0% - 100.8% with RSDs of 1.8% - 2.3%.