The effect of timne on the stability of the Cu-DDTC complex was studied by following the absorption intensity of the reaction solution (after dilution)at different time intervals.The absorbankce of the complex remains stable for at least 72 h. This allowed the process of large batches of samples,and their comfortable measurements with convenience. Thmis gives the high throughplut property to the proposed method when applied for analysis of large numper of samples in qual;ity control/analytical laboratories.