Metal furnace heated by flame as a hydride atomizer for atomic absorption spectrometry: Sb determination in environmental and pharmaceutical samples

The present work describes a metallic hydride atomizer for atomic absorption spectrometry, by evaluating the performance of the Inconel 600® tube. For this purpose, stibine was used as the model volatile compound and antimony determination in river and lake sediments and in pharmaceutical samples was carried out to assess the metal furnace performance. Some parameters are evaluated such as those referring to the generation and transport of the hydride (such as KBH4 and acid concentrations, carrier gas flow rate, injected volume, etc.), as well as those referring to the metal furnace (such as tube hole area, flame composition, long-term stability, etc.). The method presents linear Sb concentration from 2 to 80 μg L−1 range (r > 0.998; n = 3) and the analytical frequency of ca. 140 h−1. The limit of detection (LOD) is 0.23 μg L−1 and the precision, expressed as R.S.D., is less than 5% (40 μg L−1; n = 10). The accuracy is evaluated through the reference materials, and the results are similar at 95% confidence level according to the t-test.