Direct analysis of liquid and solid samples without sample preparation using laser-enhanced ionization

Abstract

Laser-enhanced ionization combined with rod–flame and graphite furnace atomizers–ionizers was used for direct analyses of high-purity orthophosphoric acid, germanium, CdHgTe alloy and silver nitrate. In standard aqueous solutions both systems give detection limits for elements down to the 1 × 10^–15 g level. The examples of CdHgTe alloys and germanium show that the transition from the analysis of solutions to the direct analysis of solid samples in a rod–flame system leads to a decrease in the matrix background signal of over two orders of magnitude. This allows for the detection of elements in solid samples without sample preparation, with detection limits down to 1 × 10^–6 ppm, which is 100 times better than for solutions. The problems with and prospects for the proposed approach are discussed.