Study on the direct analysis of solid powder biological samples using fluorination assisted electrothermal vaporization inductively coupled plasma atomic emission spectrometry with PTFE slurry modifier

A method has been described for the direct determination of Til Cu, Mn, Cr and Cd in solid biological samples without any chemical pretreatment by flu orination assisted electrothermal vaporization inductively coupled plasma a tomic emission spectrometry (ETV-ICP-AES) with slurry sampling. A polytetra fluorethylene (PTFE) emulsion was used as a fluorinating reagent to promote the vaporization of the analytes from the graphite furnace. The interface between furnace device and ICP torch and the main factors affecting the ana lytical signal were investigated systematically. The detection limits for t he determination of Ti, Cu, Mn, Cr and Cd are 6.3, 4.7, 10, 13 and 278 ng/m L, respectively; the relative standard deviations are in the range of 1.5 ( Mn) similar to 4.0% (Cd) after optimization of the operating conditions. Th e recommended approach has been applied to directly determine the trace ele ments of interest in the Chinese traditional medicine Loulu and in the soli d biological standard reference material (peach leaves, GBW 08501) with sat isfactory results.