Use of slow atomization ramp in high resolution continuum source graphite furnace atomic absorption spectrometry for the simultaneous determination of Cd and Ni in slurry powdered chocolate samples.

A methodology for simultaneous (not sequential) determination of Cd and Ni in powder chocolate samples by high-resolution continuum source graphite furnace atomic absorption spectroscopy (HR-CS-GF-AAS) and slurry sample analysis was developed. Acid digestion of the samples was not necessary, considering the high total fat content of this type of matrix (above 10 %), and no apparent deterioration of the graphite tubes was even observed once these samples were subjected to analysis. Despite the volatilities of both elements are quite different, simultaneous quantification was achieved using a slow heating ramp atomization, covering a convenient and wide temperature gradient for Cd volatilization at low temperatures and subsequent atomization of Ni at elevated temperatures, using the same heating program without an apparent change in sensitivity.