Investigations into the improvement of the analytical application of the hydride technique in atomic absorption spectrometry by matrix modification and graphite furnace atomisation. Part II. Matrix interferences in the gaseous phase of hydride atomic absorption spectrometry

Abstract

Studies of matrix interferences in hydride AAS were carried out in the presence of hydride-forming matrices. It was found that the main interference in most instances occurs in the gaseous phase of hydride atomisation. Thermodynamic calculations, coupled with spectroscopic and thermal investigations, show that the main cause of matrix interferences in the gaseous phase is the formation of diatomic molecules between the trace and matrix elements (e.g., AsSb). Therefore, significant improvements in accuracy and relative sensitivity can be obtained by using graphite tube atomisers, at temperatures >2000 °C.