APPLICATION OF RAPID ELECTROTHERMAL ATOMIC-ABSORPTION SPECTROMETRIC METHODS TO THE DETERMINATION OF AG, AL, CD AND MN IN COCAINE AND HEROINSAMPLES

Rapid methods were developed for the direct determination of Ag, Ali C d and Mn in cocaine and heroin by ETAAS using programmes omitting the charring step. Sample pretreatment was simple: dissolution in ultrapur e water or in 35.0% (v/v) HNO3 for heroin or cocaine respectively. Opt imum drying temperatures were 250 degrees C for Ag, Al and Mn, and 300 degrees C for Cd. The run cycles were 35 and 37 s, for Ag and Al resp ectively, and 36 s for Cd and Mn. The best results were obtained with Pd. Mg(NO3)(2) and (NH4)(2)HPO4, as chemical modifiers, The limits of detection were 8.6, 55.9, 2.2 and 12.4 mu g kg(-1) for Ag, Al, Cd and Mn, respectively.