Variables of solid sampling with electrothermal vaporizers and atomizers

Variables of solid sampling with electrothermal vaporizers and atomizers 

The variables that influence the solid sampling process depend on the particular sample insertion mode used. 

Analyte location in the sample The type of bond between the analyte and the solid matrix, in addition to the location of the analyte in the solid particles (viz. on the surface or occluded within) can influence absorbance measurements through differences in vaporization kinetics. One example is the determination of several metals in steel. Signals with double peaks were observed as a result of the analyte being present in two different locations of the steel grains [38]. The formation of several peaks in the atomic absorption signals was also observed in the determination of lead in plastics using a cup-in-tube device [39] and ascribed to the manner in which the plastic decomposed as the temperature was raised. Also, several peaks were observed when lead was atomized at a low pressure from copper alloys, which was also ascribed to the presence of various chemical forms of Pb or changes in its location [40]. 

The main variables influencing this sampling mode are slurry stability and concentration, and particle size. 

Slurry stability Slurries can be maintained stable for insertion into ETAs and ETVs using various approaches, namely  

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