Comparison of matrix effects in inductively coupled plasma using laser ablation and solution nebulization for dry and wet plasma conditions

Matrix effects of calcium in inductively coupled plasma-atomic emission spectrometry were investigated. Matrix effects were studied by monitoring the excitation conditions of the plasma using Zn ionic to atomic spectral line intensity ratios. Dry and wet inductively coupled plasmas with robust and non-robust conditions were compared. Laser ablation and solution nebulization sample introduction were used to produce the dry and wet plasma conditions, respectively. Low (0.61/min) and high (1.01/min) carrier gas flow rates were used to produce the robust and non-robust conditions, respectively. No differences in the trend of matrix effects for dry and wet plasmas were observed at vertical positions above normal observation height (> 8 mm height above load coil) for low and high carrier gas flow rates. However, matrix effects in the lower part of the plasma (< 8 mm height above load coil) were significantly different between dry and wet plasmas when a high carrier gas flow was used. The differences are likely due to the desolvation process. (C) 2001 Elsevier Science B.V. All rights reserved.