Study of vanadium(V) as a chemical modifier in electrothermal atomisation atomic absorption spectrometry

Abstract

Vanadium(V) in the form of NH₄VO₃ or as an aqueous solution of V₂O₅(pH > 9, ammonia solution) has been studied as a modifier for 25 analyte elements of high and moderate volatility. The maximum pre-treatment temperatures (°C) in the presence of 20 µg of V^v and 20 µg of V^v+ 4 µg of Pd^II are, respectively: Ag (900 and 1000); Al (1400); As (1450 and 1450); Au (850 and 1000); Bi (850 and 1200); Cd (800 and 800); Co (1100); Cr (1000); Cu (1000 and 1150); Fe (1550); Ga (1100 and 1350); Ge (900 and 1350); Hg (290); In (1100 and 1300); Ni (1100); Mn (1000 and 1300); P (1500 and 1550); Pb (900 and 1000); Pd (1400); Sb (1000 and 1400); Se (1550 and 1400); Sn (1300 and 1400); Te (700 and 1500); TI (1050 and 1100); and Zn (850 and 900). A high efficiency of thermal stabilisation by the mixed modifier V + Pd has been observed for most volatile analytes. Investigations using the modifier have been carried out on slurried and digested biological and environmental reference materials.