An Alternate Approach to Background Correction in Atomic Absorption Spectrometry

Abstract

An alternate approach to implementing the background correction method originally proposed by Smith and Hieftje has been developed. Its novel feature is that only a single, short duration, high current hollow cathode lamp power pulse is used per measurement cycle. The light from the lamp is measured at the beginning and end of each current pulse after Lorentz line broadening and self-reversal have had time to fully develop. The difference between the absorbance signals observed at the two different sampling intervals is not influenced by either continuum absorption or light-scattering error signals. This approach is simple to implement, uses only standard light sources, possesses the same advantages relative to the conventional auxiliary continuum source lamp method of background correction as does the Smith and Hieftje approach, and has the added feature that all light measurements are made when the source lamp emission is very intense with respect to signals from extraneous light sources.