ANALYSIS OF CARBOHYDRATES AND GLYCOCONJUGATES BY MATRIX-ASSISTED LASER DESORPTION/IONIZATION MASS SPECTROMETRY: AN UPDATE FOR 2015-2016

This review is the ninth update of the original article published in 1999 on the application of matrix-assisted laser desorption/ionization (MALDI) mass spectrometry to the analysis of carbohydrates and glycoconjugates and brings coverage of the literature to the end of 2016. Also included are papers that describe methods appropriate to analysis by MALDI, such as sample preparation techniques, even though the ionization method is not MALDI. Topics covered in the first part of the review include general aspects such as theory of the MALDI process, matrices, derivatization, MALDI imaging, fragmentation and arrays. The second part of the review is devoted to applications to various structural types such as oligo- and poly-saccharides, glycoproteins, glycolipids, glycosides and biopharmaceuticals. Much of this material is presented in tabular form. The third part of the review covers medical and industrial applications of the technique, studies of enzyme reactions and applications to chemical synthesis. The reported work shows increasing use of combined new techniques such as ion mobility and the enormous impact that MALDI imaging is having. MALDI, although invented over 30 years ago is still an ideal technique for carbohydrate analysis and advancements in the technique and range of applications show no sign of deminishing. © 2020 Wiley Periodicals, Inc.

Microarray investigation of glycan remodeling during macrophage polarization reveals α2,6 sialic acid as an anti-inflammatory indicator

Glycosylation is a widely occurring posttranslational modification. Here, we applied a quick, convenient and high-throughput strategy (lectin array) to investigate the variation in glycans on different macrophage subtypes derived from THP-1 and RAW264.7 cells. For THP-1 cells, there were more significant differences in the glycan on M2 macrophages compared to the other two subtypes. In contrast, M1 macrophages exhibited more significant glycan remodeling than the other subtypes for the RAW264.7 cell line. The response of the lectins which recogonize the N-glycan and α2,6 sialic acid was higher during polarization into anti-inflammatory phase (THP-1 derived M2 subtypes), and lower in pro-inflammatory phase (RAW264.7 M1 subtypes). The regulation of several α2,6 sialyltransferase genes was coincident with the regulation of the α2,6 sialic acid on the two cell lines. The lectin response and glycosyltranferase gene expression confirmed that α2,6 sialic acid showed higher expression in the anti-inflammatory phase. This indicated that α2,6 sialic acid was a potential indicator for the anti-inflammatory response.

Synergistic integration of FeNi magnetic nanoparticles with graphene-based porous carbon for efficient capture of N-linked glycans

Developing functional porous carbon is greatly desired for the capture of N-glycans from complex bio-samples. In this work, ferronickel graphene-based porous carbon composites (FeNi-G/PC-T, T = carbonization temperature) are facilely prepared and are characterized by the synergistic integration of magnetic separation, porosity and polar interaction. Studies of capture of N-linked glycans reveal that FeNi-G/PC-800 shows a remarkable performance to enrich N-linked glycans from standard bio-samples and real human serum, resulting in the successful profiling of 48 N-linked glycans in 5 μL human serum. Structure-property relationship studies further demonstrate that the synergistically integrated FeNi nanoparticles and graphene-based porous carbon in FeNi-G/PC-800 should play a key role in the capture performance.

Boronic acid-functionalized mesoporous magnetic particles with a hydrophilic surface for the multimodal enrichment of glycopeptides for glycoproteomics

Boronic acid-functionalized mesoporous magnetic particles with a hydrophilic surface for multimodal enrichment of glycopeptides for glycoproteomics.

Porous magnetized carbon sheet nanocomposites for dispersive solid-phase microextraction of organophosphorus pesticides prior to analysis by gas chromatography-ion mobility spectrometry

Carbon sheets were attached to magnetite (Fe₃O₄) nanoparticles. The resulting nanocomposite is shown to be a viable sorbent for use in magnetic dispersive solid-phase microextraction of three organophosphorus pesticides. The sorbent was synthesized via the sol-gel process followed by calcination and was characterized by an X-ray diffractometer, field emission scanning electron microscopy and energy dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, and Raman spectrometry techniques. The affecting parameters in the adsorption and desorption steps were assessed and optimized via response surface methodology. Following desorption with dichloromethane, the OPPs were quantified by gas chromatography along with ion mobility spectrometry detection. Under optimized conditions, the limits of detection were 1.00, 0.46 and 0.85 μg L^-1 for fenthion, malathion and chlorpyrifos, respectively. Response is linear in the concentration range of 2-500 μg L^-1 for fenthion and malathion, and 2-1000 μg L^-1 for chlorpyrifos with the determination coefficient larger than 0.9969. The intra-day and inter-day precision were from 3 to 9% and 5 to 16%, respectively. The enrichment factor was greater than 142 for all the studied pesticides. The sorbent was used for analyze spiked water and vegetable samples and gave relative recovery higher than 82%. Graphical abstract A flowchart of the synthesis of porous magnetized carbon sheet nanocomposites and the process of the magnetic dispersive solid-phase microextraction (MD-μ-SPE) of three organophosphorus pesticides prior to analysis by gas chromatography-ion mobility spectrometry (GC-IMS).

Application of Porous Materials to Carbohydrate Chemistry and Glycoscience

There is a growing interest in using a range of porous materials to meet research needs in carbohydrate chemistry and glycoscience in general. Among the applications of porous materials reviewed in this chapter, enrichment of glycans from biological samples prior to separation and analysis by mass spectrometry is a major emphasis. Porous materials offer high surface area, adjustable pore sizes, and tunable surface chemistry for interacting with glycans, by boronate affinity, hydrophilic interactions, molecular imprinting, and polar interactions. Among the materials covered in this review are mesoporous silica and related materials, porous graphitic carbon, mesoporous carbon, porous polymers, and nanoporous gold. In some applications, glycans are enzymatically or chemically released from glycoproteins or glycopeptides, and the porous materials have the advantage of size selectivity admitting only the glycans into the pores and excluding proteins. Immobilization of lectins onto porous materials of suitable pore size allows for the use of lectin-carbohydrate interactions in capture or separation of glycoproteins. Porous material surfaces modified with carbohydrates can be used for the selective capture of lectins. Controlled release of therapeutics from porous materials mediated by glycans has been reported, and so has therapeutic targeting using carbohydrate-modified porous particles. Additional applications of porous materials in glycoscience include their use in the supported synthesis of oligosaccharides and in the development of biosensors for glycans.

Fucoidan-coated core–shell magnetic mesoporous silica nanoparticles for chemotherapy and magnetic hyperthermia-based thermal therapy applications

Fucoidan-coated FeNP@SiOH@Fuc NPs have been proposed for chemotherapy and thermal therapy applications in emerging cancer therapy.

A novel carbon material with nanopores prepared using a metal-organic framework as precursor for highly selective enrichment of N-linked glycans

Protein glycosylation plays a key role in many biological processes. In this study, a novel carbon material with nanopores was prepared by carbonization of metal-organic framework (MOF) Mil-101(Cr). The parent MOF assembled from metal ions with bridging organic linkers had many fascinating properties, such as ultrahigh surface area, suitable nanopore structure, and especially a large amount of carbon after being calcined. Due to the strong interactions between carbon and glycans as well as the size-exclusion effect of pore against protein, the N-linked glycans from standard glycoprotein or complex human serum proteins could be identified with high efficiency. The simple synthesis method as well as good enrichment efficiency made this novel carbon material a promising tool for glycosylation research.