Evaluation of an Isolated Droplet Sample Introduction System for Laser-Induced Breakdown Spectroscopy

Abstract

An isolated droplet generator (IDG) has been used as a novel solution sample introduction system for laser-induced breakdown spectroscopy (LIBS). The IDG converts liquid samples to equally-spaced, uniform-sized droplets. The droplets are introduced into the region where a high-powered Nd:YAG laser beam is focused. The resulting analyte emission is spectrally and temporally resolved. The dependence of analyte emission intensity on several parameters (droplet radius, droplet production frequency, etc.) is examined. A flow injection analysis (FIA) manifold has been used to introduce samples to the IDG for quantitative analysis. Performance characteristics of the FIA/IDG/LIBS method are given. Calibration curves linear over 3 orders of magnitude have been obtained for several elements. Detection limits for solutions with the FIA/IDG/ LIBS system are in the low ppm range.