DIRECT ANALYSIS OF SOLIDS BY ULTRASONIC SLURRY ELECTROTHERMAL VAPORIZATION INDUCTIVELY-COUPLED PLASMA-MASS SPECTROMETRY

The direct analysis of solids using ultrasonic slurry electrothermal vaporization inductively coupled plasma mass spectrometry is reported. National Institute of Standards and Technology (NIST) Standard Reference Material (SRM) 1632a Trace Elements in Coal (Bituminous), Total Diet SRM 1548 and National Research Council of Canada LUTS-1 Lobster Hepatopancreas RM were analysed for a number of elements including Ni, Cu, Cr, Pb, Mn and Co. As a consequence of matrix effects, most analytes were determined using the method of standard additions, although Ni, Cu, Pb and Mn in NIST coal and Pb in LUTS-1 were successfully determined by external calibration using aqueous standards. With the exception of Cr in the coal sample, excellent agreement was obtained between the concentration determined and the certified range. Monitoring of the argon dimer during the high temperature vaporization cycle was shown to be an effective means of assessing matrix effects and selecting calibration strategies for individual analytes. Calculated limits of detection range from 0.07 ng g-1 for Co to 3.2 ng g-1 for Cr in 2 mg samples.