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- Analytical ChemistryDOI: 10.1021/acs.analchem.5c05187
- Analytical ChemistryDOI: 10.1021/acs.analchem.5c04456
- Analytical ChemistryDOI: 10.1021/acs.analchem.5c06107
- Fatty acids (FAs) are essential components of lipid metabolism and play crucial roles in biological systems. However, due to their low abundance and poor ionization efficiency, the detection of FAs in matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) poses significant challenges, making the spatial distribution of these molecules in tissues difficult to analyze. We present a novel on-tissue derivatization strategy for FAs using N,N-diethylethylenediamine (DEEA) as the derivatization reagent, which converts the carboxyl group of FAs into a positively charged […]
- Time-of-flight secondary ion mass spectrometry (ToF-SIMS), combined with principal component analysis (PCA) and multivariate curve resolution (MCR), disentangles ultrathin mixtures of Ni, NiO, and Ni(OH)2 on model Ni electrodes. By revealing a hydroxide-specific ion marker linked to hydrogen evolution reaction (HER) activity, the method offers a new framework for identifying catalytically active sites. Abstract Unambiguous identification of active sites in heterogeneous catalysis remains a major challenge, particularly for materials with ultrathin, chemically mixed surface layers. Here, we demonstrate a generalizable […]
- ABSTRACT Rationale Many perfluoroalkyl and polyfluoroalkyl sulfonic/sulfinic acids and their derivatives are classified as perfluoroalkyl and polyfluoroalkyl substances (PFASs). The use of mass spectrometry techniques to analyze these compounds has attracted considerable research attention. Methods In this article, we employed high-resolution electrospray ionization tandem mass spectrometry (HR-ESI-MS/MS) and all-ion fragmentation (AIF) in negative ion mode to investigate gas-phase F-atom migration reactions of various perfluoroalkyl and polyfluoroalkyl sulfonic/sulfinic anions, particularly those yielding FSO3 â or FSO2 â. Results HR-ESI-MS/MS of CF3SO3 […]
- ABSTRACT Rationale Linaclotide is an important peptide drug used to treat irritable bowel syndrome with constipation (IBS-C). However, structurally related impurities in peptide drugs can be generated during synthesis, storage, or transport, which compromise the quality and safety. Therefore, developing a highly sensitive analytical method for impurity detection is of great significance. Methods A liquid chromatographyâhigh resolution mass spectrometry (LC-HRMS) method was developed. Linaclotide samples were directly analyzed using an Orbitrap mass spectrometer with an electrospray ionization (ESI) source operated […]
- Analyst, 2026, Advance ArticleDOI: 10.1039/D5AN01248A, Paper Open Access   This article is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported Licence.Pawanjit K. Sandhu, Ryland T. Giebelhaus, Ryan Hayward, Tingting Zhao, Alix Tucker, Daniel Gaudet, Tao Huan, Susan J. MurchNon-protein amino acids (npAAs) are metabolites with amine (NH2) and carboxyl (COOH) moieties. Their natural diversity is not well understood. We created an analytical toolkit including SOPs, statistical methods and a searchable database of 332,154 metabolites for future studies of npAA.To cite […]
- ABSTRACT Rationale Pinellia ternata (Thunb.) Ten. ex Breitenb. is a perennial herb that has a long history of use in traditional Chinese therapy due to its diverse pharmacological activities including antiemetic, antitussive, and anti-tumor activities. Characterization and quality control of P. ternata will be challenging due to its highly complex and diverse chemical composition. Methods In this study, we utilized microwave plasma torch desorption ionization mass spectrometry (MPT-MS) for the first time to investigate P. ternata for the purpose of […]
- ABSTRACT Rationale Increasingly, more laboratories are measuring the triple oxygen isotope values of phosphate. Standardization is key to having good interlaboratory results. Here, we present the triple oxygen isotope values of a suite of standards using fluorination and compare them with previously reported triple oxygen isotope values. Methods Silver phosphate (~2â3âmg) was fluorinated in nickel reaction vessels, and the resulting O2 was analyzed on a Thermo MAT 253 for the paired δ17O-δ18O value (Îâ˛17O). Although the δ18O and δ17O values […]
- ABSTRACT Rationale Charmatography based pphytochemical extraction to identify and quantification of volatile bioactive compounds providing chemical profiling to evaluate their pharmacological significance. Methods The component composition of essential oils of Bilacunaria microcarpa (M. Bieb.) Pimenov & V.N.Tikhom. and Peucedanum ruthenicum M. Bieb. distributed in the flora of Azerbaijan was studied using the method of gas chromatographyâmass spectroscopy. Results In the composition of the essential oil of B. microcarpa, 70 components were found, of which 59 were identified; the mains of […]
- ABSTRACT Rationale Compounds-specific stable isotope analysis (CSIA) is an advanced tool for assessing the sources and fates of organic amines in environments. The use of gas chromatographyâcombustionâisotope ratio mass spectrometry (GC-C-IRMS) remains constrained by the thermal stability, high polarity, and the typically low environmental concentrations of organic amines. Methods The development of suitable derivatization strategies for polar organic amines can broaden the applicability of GC-C-IRMS. To establish a nitrogen stable isotope analytical method for polar organic amines in the atmosphere, […]
- ABSTRACT Rationale The search for novel natural compounds and the identification of known ones is a challenge for the scientists working in different fields of plant science. Due to its accessibility, GCâMS is the most frequently applied method for analysis of extracts and fractions from plants of the subfamily Amaryllidoideae (Amaryllidaceae s.s.), known as a source of molecules with potent anti-acetylcholinesterase, anti-tumour, and antiprotozoal activities. Methods Thirty-four standard alkaloids with haemanthamine- and crinine-type scaffolds were subjected to electron impact gas […]
- The gut microbiome is increasingly being shown to exert multiple biological effects upon the host. This activity can occur via the production of microbial-derived metabolites. Gut bacteria have been demonstrated to convert dietary polyunsaturated fatty acids (PUFAs) into oxygenated metabolites called oxylipins, which can exert potent lipid mediator functions. The products derived from C-18 fatty acids are collectively known as octadecanoids and have been shown to associate with multiple disorders including allergy and metabolic dysregulation. To study the role of […]
- The Prevotella genus are strict anaerobic organisms associated with opportunistic infections in the vaginal, oral, and gastrointestinal cavities. During infection, virulence mechanisms such as adhesion to host tissues, invasion of cells and connective tissue, and evasion of the immune system are essential for bacterial establishment and host persistence. In the present study, we investigated the adhesion to human extracellular matrix proteins, biofilm formation, Matrigel invasion, and plasminogen activation of strains from the Prevotella species, including P. intermedia, P. melaninogenica, and […]
- Protein glutathionylation is traditionally viewed as a protective mechanism that shields cysteine residues from irreversible oxidative damage. Its broader functional roles remain poorly understood, in part due to technical limitations in detecting this modification at scale. Here, we develop and leverage a new mass spectrometry approach that preserves protein glutathionylation, thereby revealing its widespread distribution across the proteome in cell models, worms, mice and human cardiac tissues. In all cases, we find that glutathionylation sites are enriched at both protein […]
- Publication date: Available online 15 January 2026Source: International Journal of Mass SpectrometryAuthor(s): Zixuan Huang, Ran Tian, Yun Gao
- Analytical ChemistryDOI: 10.1021/acs.analchem.5c05804
- Natural variability in stable isotope ratios provides critical constraints on elemental cycling in nature without the need for the introduction of artificial tracers. While such data are widely used in environmental studies, they are not as widely employed in biomedical research, despite vast potential. One critical hurdle to the adoption of such techniques in biomedical studies is sample throughput. Elemental purification via ion-exchange chromatography and isotopic analysis via multiple collector inductively coupled plasma mass spectrometry (MC-ICP-MS) are time-consuming, requiring long […]
- Bile acids (BAs) are endogenous signaling molecules with diverse biological functions. In cholestasis, conjugated BAs are markedly elevated, making their ratio to unconjugated BAs a critical diagnostic biomarker. Accurate quantification of BAs is pivotal for assessing cholestatic disease progression. Conjugated BAs contain a fragile amide bond that is susceptible to hydrolysis in biological samples, resulting in an artificially low ratio of conjugated-to-unconjugated BAs. Here, we systematically investigated the benchtop stability of BAs in murine biological samples using liquid chromatography-mass spectrometry. […]
- Chemistry â A European Journal, EarlyView.
- Accurate biomonitoring of non-persistent endocrine-disrupting chemicals (EDCs) requires robust quantitative methods for reliable human exposure and risk assessment. Building on previous work showing that direct measurement of bisphenol A and its conjugated metabolites in human urine reveals substantial underestimation in commonly used indirect, hydrolysis-based approaches, this study addresses the broader need for direct assays of other short-lived EDCs. Here, a direct liquid chromatographyâtandem mass spectrometry method is developed and validated for the simultaneous quantification of bisphenol S (BPS), propylparaben (PP), […]
- Mass spectrometry imaging enables spatially resolved, label-free detection of metabolites in tissue and culture systems, providing insight into their metabolic landscape and spatial distribution. However, conventional approaches often lack the spatial resolution and specificity needed to investigate metabolic heterogeneity at the single cell level, particularly in physiologically relevant models. Here, we present a single cell ambient mass spectrometry imaging platform, enabling direct chemical mapping of metabolites at 10 um resolution. This method integrates cell labelling, high resolution microscopy and APMALDI […]
- Matrix-assisted laser desorption/ionisation mass spectrometry imaging (MALDI-MSI) is a powerful technique for studying lipid distribution in carotid plaques, key to understanding atherosclerosis. This study aimed to improve sample preparation for MALDI-MSI-based spatial lipidomics of carotid plaques by improving both matrix application and tissue handling. Human carotid plaques were collected from endarterectomy patients with ethical approval and sectioned at 10 um thickness for MALDI-MSI. We compared eight sample preparation methods, including hydroxypropyl methylcellulose-polyvinylpyrrolidone (HPMC-PVP) embedding media and Cryofilm-type IMS to provide […]
- Major depressive disorder (MDD) is a complex psychiatric condition with significant individual and social impact and marked variability in treatment response. Identifying biomarkers that predict antidepressant efficacy remains a major challenge, and metabolomic approaches offer a powerful tool to uncover biochemical changes associated with depression and treatment outcome. The prefrontal cortex and the hippocampus are key brain regions involved in the pathophysiology of MDD and antidepressant response. Fluoxetine, one of the most commonly prescribed antidepressants, influences not only serotonergic signaling […]