DETERMINATION OF ALUMINUM IN CHEWING GUM SAMPLES USING ELECTROTHERMALATOMIC-ABSORPTION SPECTROMETRY AND SLURRY SAMPLE INTRODUCTION

A slurry-based electrothermal atomic absorption spectrometric procedur e for the rapid determination of aluminium in chewing gum samples is d iscussed. To achieve a sufficiently small particle size, the samples h ave been first submitted to a mild calcination stage. Suspensions have been then prepared from the ground carbonaceous residues in a medium containing 8% v/v ethanol, 1% v/v concentrated nitric acid, 0.2% m/v m agnesium nitrate and 4% v/v concentrated hydrogen peroxide. Aliquots o f 10 mu l have been introduced in the furnace and dried at 200 degrees C for 20 s. No ashing step has been used. Wall atomization has been p erformed at 2600 degrees C. Calibration has been carried out with aque ous standards. The reliability of the procedure has been checked by an alyzing standard reference materials and by comparing the results for eight commercial samples with those found by a conventional procedure based on the complete dissolution of the samples. The results for the commercial samples are in the 36-64 mu g g(-1) range, only one of the samples giving a higher value of 123 mu g g(-1).