Trace Elemental Analysis of Selenium and Antimony Using Hydride Generation Coupled to Laser Induced Breakdown Spectroscopy

Abstract

Detection of metalloids such as selenium and antimony in the environment is important for technological and health reasons. Selenium in trace amounts has biological importance and hydride generation is one of the most effective sample introduction techniques for analytical atomic spectroscopy measurements. Aqueous solutions of selenium and antimony are converted to a gaseous form via hydride generation and the gas is delivered to an atomizer for measurement. Laser Induced Breakdown Spectroscopy, LIBS, is the atomic emission spectroscopy method that is used in this research to measure the gaseous form of the analyte generated by the hydride approach. Analyte atoms are atomized and excited by a laser-produced plasma and the atomic emission is measured at an element-specific wavelength. Optimization of the instrument to obtain the maximum wavelength of emission was performed using a 10 ppm solution of each element. The optimized parameters were used to measure various concentrations of each element in solution ranging from 0 to 10 ppm. A calibration curve was generated using the wavelength to plot intensity as a function of concentration. A limit of detection, LOD, was determined using the data from the calibration curve. Additional research in this work included studying the characteristics and properties of laser produced-plasmas and determining how this information can be utilized in further studies of trace analysis of selenium and antimony.