Laser-induced fluorescence in a furnace: A viable approach to absolute analysis?

Abstract

The possibility of performing absolute analysis by laser-induced atomic fluorescence in a graphite tube atomizer is discussed. At the sensitivities which are typical of these measurements, i.e., at absolute levels of the order of femtograms, it is argued that the lack of certified reference materials and the practical limitations in preparing standard solutions constitute the major incentives to the development of absolute analysis. The various theoretical and experimental parameters needed in the procedure of converting a measured fluorescence signal, e.g., a voltage, into the corresponding number of emitting atoms are discussed and evaluated with respect to a typical determination of a toxic element like thallium.