Multivariate investigation of matrix effects in inductively coupled plasmaatomic emission spectrometry using pneumatic or ultrasonic nebulization

A multivariate interference study was carried out using a low power inducti vely coupled plasma atomic emission spectrometer, after optimization of ope rating parameters in order to achieve both plasma robustness and maximum si gnal to background ratios. The method, based on the empirical modelling and experimental design concepts, provided a multivariate quantification of in terferences caused by complex matrices containing Na, K, Ca, Al and Fe, at concentration levels ranging from 10 to 5000 mu g ml(-1), deducing the comp lex relationships between interfering effects and matrix composition. In or der to test the plasma excitation conditions, the Mg II 280.270 nm to Mg I 285.213 nm line intensity ratio was measured for each combination of matrix elements. Both Meinhard and ultrasonic nebulization were considered for co mparison.