Laser-excited atomic fluorescence spectrometry in an atomic absorption graphite tube furnace

Abstract

A dye laser pumped by an excimer laser was used for laser-excited atomic fluorescence spectrometry (LEAFS) in a Perkin-Elmer HGA-500 graphite tube atomiser. The tube furnace was modified for LEAFS by drilling two 4-mm holes across the centre of the tube. Laser light was either passed down the bore of the tube or across the centre of the tube and fluorescence was detected at a right angle. Atomisation was investigated with and without a L'vov platform. Resonance and non-resonance LEAFS transitions were studied. Detection limits for Ag, Co, Cu, In, Mn, Pb and Tl were 8,500, 400, 80, 80, 7 and 100 fg, respectively. The linear dynamic ranges (relative slope of one) for these elements extended 4–6 orders of magnitude above the detection limit. The relative standard deviation for 14 measurements of 200 pg of lead was 10%.