Off-line coupling of capillary isotachophoresis separation to IRMPD spectroscopy for glycosaminoglycans analysis: Application to the chondroitin sulfate disaccharides model solutes

Laser Photodissocation, Action Spectroscopy and Mass Spectrometry Unite to Detect and Separate Isomers

The separation and detection of isomers remains a challenge for many areas of mass spectrometry. This article highlights laser photodissociation and ion mobility strategies that have been deployed to tackle...

Applications of infrared spectroscopy in polysaccharide structural analysis: Progress, challenge and perspective

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Functional properties of polysaccharides depend on their structural features.

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IR spectroscopy is widely used in polysaccharide structural analysis.

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Classical applications of IR spectroscopy in polysaccharide are reviewed.

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IR integrating techniques can considerably expand its application scope.

Polysaccharides are important biomacromolecules with numerous beneficial functions and a wide range of industrial applications. Functions and properties of polysaccharides are closely related to their structural features. Infrared (IR) spectroscopy is a well-established technique which has been widely applied in polysaccharide structural analysis. In this paper, the principle of IR and interpretation of polysaccharide IR spectrum are briefly introduced. Classical applications of IR spectroscopy in polysaccharide structural elucidation are reviewed from qualitative and quantitative aspects. Some advanced IR techniques including integrating with mass spectrometry (MS), microscopy and computational chemistry are introduced and their applications are emphasized. These emerging techniques can considerably expand application scope of IR, thus exert a more important effect on carbohydrate characterization. Overall, this review seeks to provide a comprehensive insight to applications of IR spectroscopy in polysaccharide structural analysis and highlights the importance of advanced IR-integrating techniques.

Screening of the Chemical Composition and Identification of Hyaluronic Acid in Food Supplements by Fractionation and Fourier-Transform Infrared Spectroscopy

Hyaluronic acid, together with collagen, vitamins or plant extracts, is a part of many cosmetic and food preparations. For example, this polysaccharide is used in formulation of many food supplements due to its protective effects on human health. In this work, the screening of the chemical composition of three chosen dietary supplements (powder, tablets and capsules) containing hyaluronic acid was carried out using Fourier-transform infrared spectroscopy. Because of the low amount of analyte in all these samples, it was isolated or concentrated prior to the analysis using a suitable sequential fractionation protocol. Individual isolation procedures were established for each sample based on their declared composition. Firstly, the major components such as collagen or vitamins were removed to obtain polysaccharide fractions by the enzymatic treatment and/or washing out with the appropriate solvents. In some cases, the water insoluble part was removed from the rest dissolved in water. Then, hyaluronic acid was precipitated with copper(II) cations and thus separated from the other polysaccharides. Finally, the analyte was identified in the enriched fractions by the characteristic vibrational bands. The amount of hyaluronic acid in the purified fractions was determined in three ways: gravimetrically, spectrophotometrically, and using isotachophoresis. The combination of the appropriate preparative and analytical steps led to the successful evaluation of chemical composition, finding and quantification of hyaluronic acid in all the studied samples.

Advances in mass spectrometry-based glycomics-An update covering the period 2017-2021

The wide variety of chemical properties and biological functions found in proteins is attained via post-translational modifications like glycosylation. Covalently bonded to proteins, glycans play a critical role in cell activity. Complex structures with microheterogeneity, the glycan structures that are associated with proteins are difficult to analyze comprehensively. Recent advances in sample preparation methods, separation techniques, and MS have facilitated the quantitation and structural elucidation of glycans. This review focuses on highlighting advances in MS-based techniques for glycomic analysis that occurred over the last 5 years (2017-2021) as an update to the previous review on the subject. The topics of discussion will include progress in glycomic workflow such as glycan release, purification, derivatization, and separation as well as the topics of ionization, tandem MS, and separation techniques that can be coupled with MS. Additionally, bioinformatics tools used for the analysis of glycans will be described.