Multidimensional liquid chromatography with parallel ICP MS and electrospray MS/MS detection as a tool for the characterization of arsenic species in algae

Abstract

An analytical strategy was developed for the characterization of arsenic species in a Laminaria algae. The approach was based on multidimensional liquid chromatography (LC) including sample extract cleanup by size-exclusion LC, separation of arsenic species by anion-exchange LC, verification of the chromatographic purity of arsenic-containing fractions, and their further purification, if necessary, by reversed-phase (RP) HPLC. The complementarity of ICP MS, used as the chromatographic detector, and ES MS/MS, employed for the identification of the peaks observed, was demonstrated. The species found were: arsenosugar A 11.7+/-0.5 microg g(-1), AsV 10.9+/-2.1 microg g(-1), arsenosugar B 2.22+/-0.07 microg g(-1), arsenosugar D 1.5+/-1.2 microg g(-1), a newly detected arsenosugar 1.13+/-0.07 microg g(-1), arsenosugar C 0.61+/-0.04 microg g(-1), DMA 0.42+/-0.02 microg g(-1) and these accounted for >99% of the arsenic present. The identities of all the species, except the newly detected compound, were doubly checked by matching the retention times of chromatographically pure (after the 3rd LC dimension) species with standards and by ES MS/MS.

Inductively coupled plasma mass spectrometry in separation techniques: Recent trends in phosphorus speciation

“…However, some widely studied elements for biochemical speciation such as arsenic and phosphorus are monoisotopic and no characteristic isotopic abundance pattern can be obtained. In such cases, application of ESI-MS/MS and structural fragmentation patterns from this (also known as CID) are considered necessary to avoid misidentifying metal-containing compounds using only chromatographic retention time and molecular mass information [14].…”

Element Speciation Analysis

“…They are an inevitable means for quality control in speciation, and provide the best chances to obtain "correct" speciation results and even identification of heretofore unknown species. In analytical systems with only one separation and one detection system, the risk of coelution, impossibility of species identification or misidentification is high (e.g., McSheehy et al 2002), but this problem can be solved by employing different systems in various ways.…”

“…Often it is necessary to combine schemes 1 and 2 in different ways (Michalke 1999;Michalke and Schramel 1997b;Szpunar 2000a;Chassaigne and Lobinski 1998b). An orthogonal flow chart is shown in Figure 3.7, and a typical current example has been reported by McSheehy et al (2002), where sample clean-up and size characterization by SEC is followed by RPC-ICP-MS paralleled by CZE-ICP-MS. Additional molecular and structural information is performed by ESI-MS/MS detection.…”

Speciation Analysis of Arsenic in Traditional Chinese Medicines by Hydride Generation-Atomic Fluorescence Spectrometry

“…Among them, the most commonly used methods include ultraviolet spectrometry, 3,4 hydride generation-atomic absorption spectrometry (HG-AAS), [5][6][7][8][9][10][11][12][13] inductively coupled plasma-atomic emission spectrometry (ICP-AES), [14][15][16][17] electrothermal atomic absorption spectrometry (ET-AAS), [18][19][20] atomic fluorescence spectrometry (AFS) 21,22 and liquid chromatography-inductively coupled plasma-mass spectrometry (LC-ICP-MS). [23][24][25][26][27] ICP-MS is a sensitive analysis technique for the determination of arsenic in very low levels, while liquid chromatography is one of the most widely used separation methods for arsenic speciation. Therefore, LC-ICP-MS is used for the speciation analysis of arsenic in various samples generally.…”