Quantitative determination of the sulfur-containing antioxidant ergothioneine by HPLC/ICP-QQQ-MS

Abstract

A HPLC/ICP-QQQ-MS method for quantifying the health-relevant sulfur species ergothioneine was developed and applied to human cells and mushrooms.

Selenoneine and ergothioneine in human blood cells determined simultaneously by HPLC/ICP-QQQ-MS

“…19,29 Hence, it was used to overcome spectral interferences on 32 20,29 Reversed-phase chromatography prior to ICP-QQQ-MS detection allowed the separation of ergothioneine and selenoneine from several sulfur and selenium species in cell cultures and mushroom extracts. 21 The chromatographic conditions (Gemini C6-Phenyl 4.6 × 150 mm column with a mobile phase at alkaline pH) used in that study, however, were not compatible with the complex blood matrix; although the retention and separation of ergothioneine and selenoneine were initially acceptable, the column resolution rapidly declined after several injections of the blood cell lysates. Therefore, we sought an alternative approach ensuring stable separation of the target species even after the injection of many samples with a heavy matrix load such as human blood cells.…”

“…Sulfur and selenium standard solutions used for HPLC/ICP-QQQ-MS analysis were obtained as previously reported. [21][22][23] Standards were prepared fresh daily from aqueous stock standard solutions, kept at 4°C, by dilution with water.…”

“…For signal enhancement, 1% CO2 in Ar was used as optional gas at a flow rate of 12% of the carrier gas flow. 27 Monitoring of sulfur and selenium occurred in the mass shift mode after the reaction with oxygen as detailed previously, 21 using integration times of 0.05 s and 0.3 s for sulfur and selenium, respectively (typical ICP-QQQ-MS settings are given in supplementary material, Table S 1…”

Investigation of ICP‐MS/MS for total sulfur quantification in freshwater dissolved organic matter

“…The use of both quadrupoles and oxygen in the CRC allows for the removal of spectral interferences for all isotopes of sulfur and accurate quantification of trace-level 32 S despite spectral overlap with the abundant 16 O 2 + (Baken et al, 2011;Balcaen et al, 2015;Bolea-Fernandez et al, 2017;Giner Martínez-Sierra et al, 2015). This instrumentation has been used to quantify sulfur in many complex organic matrices, including natural organic matter from marine environments (Ksionzek, 2019;Ksionzek et al, 2018;Lechtenfeld et al, 2011), biomolecules (Amaral et al, 2015;Fernández et al, 2012;Gong et al, 2015;Kroepfl et al, 2017;Zhu et al, 2015), wine (Lajin & Goessler, 2019), and crude oil (Fletcher et al, 2020(Fletcher et al, , 2021Walkner et al, 2017). Indirect quantification of sulfur associated with DOM has been done by quantifying total sulfur in freshwater samples by ICP-MS/MS and then subtracting the concentration of sulfate determined by ion chromatography (Ossola et al, 2019); however, at present, there is no published method for direct quantification of sulfur in freshwater DOM by ICP-MS/MS.…”

Assessment of the Potential and Limitations of Elemental Mass Spectrometry in Life Sciences for Absolute Quantification of Biomolecules Using Generic Standards

“…In this context, it is clear nowadays that inductively coupled plasma (ICP)–MS is gathering momentum in Life Sciences research, especially for its potential to provide absolute quantification of biomolecules on the sole condition that an ICP-detectable element (any except C, H, N, O, and F) is present or artificially linked. ,, In this line, hybrid liquid chromatography (LC)–MS configuration with both elemental (ICP) and molecular (electrospray ionization) MS detection in parallel has been already successfully applied to identify and quantify target peptides and proteins , and other biomolecules (e.g., metabolites in urine or antioxidants in water extracts of oyster mushrooms) , of interest in biological samples without specific standards. The elemental quantification achieved using ICP–MS can be easily translated into biomolecule absolute quantities, provided the molar ratio element/molecule (stoichiometry) is previously determined using molecular MS. Interestingly, such great potential relies on the assumption that ICP–MS response is species-independent, which is still an intriguing and controversial issue.…”