SIMPLEX OPTIMIZATION OF CONDITIONS FOR THE DETERMINATION OF ARSENIC IN ENVIRONMENTAL-SAMPLES BY USING ELECTROTHERMAL ATOMIC-ABSORPTION SPECTROMETRY

Simplex optimization was used to efficiently delineate the optimum exp erimental conditions to be used for the electrothermal atomic absorpti on spectrometric analysis of arsenic in a standard reference material of marine origin. Four experimental variables, were considered: ashing temperature, atomization temperature, modifier concentration, and ato mization ramping time. This combination of methods and materials provi des a powerful means of rapidly improving the experimental conditions used for analysis of arsenic in a wide variety of samples of environme ntal origin. Excellent recoveries of arsenic were obtained when using the optimum electrothermal atomic absorption spectrometry conditions t o analyze standard solutions of arsenobetaine, arsenocholine and tetra methylarsonium iodide.