Abstract: Objective: To establish a new determination method of trace-copper in Nanyang color wheat. Methods: Selecting Nanyang grey wheat, blue wheat, common violet wheat, viotet hard-wheat and Zhou wheat 16 as the raw materials, copper-selective electrode with direct reading concentration method was adopted. It compared it with the China Standard (GB/T5009.13-2003) for determining trace copper in Nanyang color wheat, after the samples being digested by high- pressure microwave. Results: The recovery is in range 86.5%～102.0% by standard addition method. The relative stan- dard deviations(RSD) is between 1.1%～3.1%(n=11). The lowest detection limit of copper is 0.0026 mg/L. The linear range is 0.032～65 mg/L. Conclusions: This method is found to be direct-reading, quick, simple, sensitive and accurate. The analytical results are satisfactory.

Key words: ion-selective electrode, direct-reading concentration method, trace-copper, microwave digestion, Nanyang color wheat flour, rapid determination