Effect of particle size in the analysis of botanical samples by slurry sampling and fluorination–electrothermal vaporization inductively coupled plasma atomic emission spectrometry
In this paper, a method for the direct determination of refractory elements B, Cr, Ti and Mo in botanical samples with slurry sampling and fluorination electrothermal vaporization inductively coupled plasma spectrometry has been developed using polytetrafluorethylene as a fluorination agent. A study of the effect of particle size indicated that when the slurry particles were less than 170 µm, intensities were identical to those obtained with aqueous solutions. As a consequence, the latter can be used as calibration standards for the determination of the trace elements in botanical samples. RSDs were generally less than 5% at a concentration of 0.2 µg ml–1(n= 9), and the results obtained were in good agreement with certified values of reference samples. The results indicate that particle size effects can be reduced by high temperature in situ fluorination in the graphite furnace.