Analysis of Copper and Lead in Aerosols with Laser-Induced Breakdown Spectroscopy

Laser-induced breakdown spectroscopy (LIBS) was applied to the analysis of aerosolized Cu- and Pb-bearing particles generated from aqueous solutions. A nitrogen-driven nebulizer was utilized to aerosolize Cu- and Pb-spiked solutions. The liquid matrix of the aqueous droplets was evaporated before the LIBS analysis, and the remaining gas-phase analyte-rich aerosols were analyzed in a LIBS system that featured a 1064 nm Nd:YAG laser, a Czerny-Turner spectrometer, and an ICCD camera. The Cu and Pb concentrations in the aerosol streams were 0.26-1.29 ppm and 0.40-1.19 ppm, respectively. Laser diffraction and the particle size distributions of the aqueous aerosols were obtained to indirectly demonstrate the evaporation of the liquid matrix. Highly linear calibration curves (R2 = 0.995 for Cu and R2 = 0.987 for Pb) and acceptable limits of detection (2 ppb for Cu and 9 ppb for Pb) and quantification (5 ppb and 28 ppb) were obtained. The applications of the presented methodology include the near-real-time and in situ analysis of wastewater and gas-phase aerosols contaminated with heavy metals.