Application of Fast Grey RA to the spectrophotometric determination of copper in liver of Egyptian camels

The ortho-orthohydroxyazo dye 15690-Solochromate Fast Grey RA, CI mordant Black 19 (reddish navy-blue black) has been used as a reagent for the spectrophotometric determination of copper in liver of Egyptian camels. To determine copper digest, 1-g dry liver samples with 5 ml of each of 50% v/v sulfuric and concentrated nitric followed by 3 ml hydrogen peroxide, get rid of excess acid by repeated evaporation and washing, transfer quantitatively to 100 ml flask, make with water up to volume, to 1 ml add 2 ml 0.05 N nitric, 2 ml 0.2 M ascorbic acid, 3 ml 0.005% FG make up with water to 10 ml. Measure extinction at 555 mμ. Such a procedure gave satisfactory results as compared to the DEDTC procedure and a recovery of 98.8%.