A CRITICAL SURVEY OF HYDRIDE GENERATION TECHNIQUES IN ATOMIC SPECTROSCOPY

Formation of the hydrides of antimony arsenic, bismuth, germanium, lead, selenium, tellurium and tin by reaction with sodium tetrahydroborate(III) affords an excellent method for the separation of these elements as gases from a wide range of matrices. Excellent low limits of detection are attained when this separation method is combined with atomisation of the hydride in a heated quartz tube in the optical axis of a conventional atomic absorption spectrometer but there are many interferences to contend with both at the hydride generation stage and in the atomisation process. Hydride generation is also used in conjunction with ICP emission spectrometers. It is particularly useful for the determination of arsenic and selenium which suffer considerable spectral interferences caused by radicals in flame AAS. Implications of recent advances in the application of this separation procedure for the determination of hydride forming elements by atomic absorption and also ICP atomic emission spectrographic techniques are discussed.