Speciation analysis by small-bore HPLC coupled to ICP-MS

Abstract

Although HPLC-ICPMS has established itself as the analytical technique of choice for elemental speciation analysis, there are some remaining limitations, mainly concerning post-column dispersion effects and the degradation of the ICP stability and ionization efficiency due to organic or saline mobile phases. The application of small-bore columns in conjunction with low dead-volume interfaces proved very useful for overcoming these problems, since they can provide lower matrix load and reduced peak dispersion, along with minimization of sample size and solvent consumption, faster chromatographic separations, better resolution and sensitivity.Since, more work is expected to be reported in this area, we review recent research in the field of speciation analysis by small-bore HPLC coupled to ICPMS, with the emphasis on significant advances in methods and instrumentation, relevant applications and current limitations.

Determination of selenium urinary metabolites by high temperature liquid chromatography-inductively coupled plasma mass spectrometry

“…1.0 mL min −1 ) could be more or less tolerated by the detection system [18], leading to poor stability, instrumental drift and the need of frequent cleaning/replace of the interface cones. A way to overcome these problems is to decrease the mass of solution introduced into the ICPMS by working at low liquid flow rates [19] or to use a mobile phase without modifier.…”

Elemental and Isotopic Mass Spectrometry

“…Challenges remain when gradient elution is required, and quantification becomes a bit more difficult, but possible solutions such as counter gradients are already published [64,[75][76][77][78]. The addition of oxygen to the plasma makes an isocratic separation with an organic solvent "routine."…”

Suitable interface for coupling liquid chromatography to inductively coupled plasma-mass spectrometry for the analysis of organic matrices. 1 Theoretical and experimental considerations on solute dispersion

“…According to Templeton et al [1,2] speciation analysis consists in identifying and quantifying different chemical species of a particular element in a given sample. It has become an important field of research over the past few years in several areas including biochemistry, environmental chemistry, ecotoxicology, pharmaceuticals, petrochemicals, and nutrition science [3].…”

“…Some key issues have to be considered for coupling LC to ICP-MS in case of organic matrices [3]: (i) metal contamination from the chromatographic system and/or the stationary phase and/or the mobile phase [3], (ii) plasma instabilities due to the solvent load, especially in case of organic mobile phases [3], (iii) signal fluctuations in gradient elution depending on plasma parameters [37] and (iv) solute dispersion into the interface located between LC and ICP-MS. The interface is made of a sample introduction system (SIS) and a possible flow splitter prior to SIS which may be required, in case of organic matrices, to reduce the amount of solvent entering plasma and hence to decrease plasma instabilities [3]. The solute dispersion in the interface unit is a critical issue because that can result in additional solute band broadening and hence in significant loss in both sensitivity and separation quality.…”