Experimental control of the solvent load of inductively coupled argon plasmas and effects of the chloroform plasma load on their analytical performance

Introduction of organic/hydro-organic matrices in inductively coupled plasma optical emission spectrometry and mass spectrometry: A tutorial review. Part I. Theoretical considerations

“…Ideally, compared to conditions without aerosol, the aerosol reaching the plasma should modify neither excitation temperature and electron number density 1 nor the ions extraction conditions in the case of ICP-MS [67]. Various features have been described to define an ideal aerosol: (i) tertiary aerosol drop size distribution: the drop diameter should be lower than the maximum acceptable by the plasma (i.e., d ≤ 10 µm); (ii) solvent load: this parameter should span 20 to 40 mg min -1 for aqueous matrices, whereas it is solvent dependent in the case of organic/hydroorganicmatrices [68]; (iii) dissociation energy: solvents with low dissociation energies will 1 Five fundamental properties of ICP discharges were claimed by Hasegawa and Haraguchi for ICP-OES [65]: plasma temperatures, electron number densities, atom and ion emission lines intensities, number densities of analyte and argon species, and spectral line widths. Two out of the five properties have been particularly studied, namely the plasma excitation temperature and electron number density [65].…”

“…The term "solvent load" was introduced by Maessen et al and defined as "the amount (mass) of solvent that enters the plasma in unit time" [68]. The solvent load must be lower than the maximum acceptable so as to minimize the plasma energy consumed by the solvent molecules.…”

“…[14, 68,[84][85][86].The experimental studies carried out on a wide range of organic solvents allowed evaluating the degree of plasma tolerance towards these matrices despite the variability of concepts and criteria employed ( [93].A rather good correlation was also found between the measured evaporation rates and the "limiting aspiration rates", i.e. plasma showing less tolerance for solvents with high evaporation rates, except for chlorinated hydrocarbons and alcohols [84].…”

Reduction of polyatomic ion interferences in inductively coupled plasma mass spectrometry by cryogenic desolvation

“…Typical applications have included the determination of trace metals in lubricating oils (68), crude oils (69), and the usual organicaqueous eluents used in high-performance liquid chromatography (HPLC) (70). However, present techniques often give rise to operating difficulties, and a number of more fundamental studies have identified a range of potential problems associated with the introduction of organic solvents into the plasma (67,71,72). These problems include deposition of carbon on the torch and sampling cones of the ® Percentage natural abundance in parentheses.…”

“…Volatile organic solvents cause instability in the ICP due to extremely high solvent transport efficiency in the introduction system and excessive solvent loading of the plasma (73). In order to alleviate many of these difficulties, cooled spray chambers (63,64,71,72), a reduction in sample uptake rates (66,67), increased forward power (64), and the addition of a small flow of oxygen (~ 2%) into the nebulizer gas to minimize carbon deposition (64), have been suggested. …”