Analytical evaluation of totally pyrolytic graphite cuvettes for electrothermal atomic absorption spectrometry

The performance characteristics of electrothermal atomiser cuvettes made of totally pyrolytic graphite (TPG) are compared to those of coated and uncoated electrographite. An analytical programme was devised to determine the useful operational lifetime of each cuvette and assess the effect of cuvette age on the sensitivity and precision of the determinations of lead, manganese and vanadium by atomic absorption spectrometry. The main advantages of TPG are enhanced cuvette durability and improved sensitivity and precision, especially for involatile elements. The characteristics of uncoated electrographite were generally unsatisfactory compared to the pyro-coated and TPG cuvettes studied.