Spectrophotometric Determination of Copper in Ginseng

In presence of CPC, copper (Ⅱ) reacts with chrome azurol S in the acidic medium to form a greenish blue colord three-component complex was reported. Its absorption maximum at 622 nm, and molar absorptivity of 8.8×10~4 L·mol~(-1)·cm~(-1). Beer's law holds in the concentration range for copper (Ⅱ) of 2～15 μg/25 mL. The proposed method proves to be sensitive and selective, and has applied to verify microamounts of copper in Ginseng with satisfactory results.