Fetal development is a vulnerable period for exposure to per- and polyfluoroalkyl substances (PFAS). However, certified analytical standards do not exist for many PFAS, limiting our ability to quantify overall exposure burden to PFAS as a chemical class. PFAS-focused nontargeted analysis (NTA) enables detection of PFAS for which chemical standards may not exist. The overall objectives of this study were to provide a more comprehensive picture of PFAS exposure in cord blood, develop cumulative exposure burden scores for the PFAS detected, and evaluate differences in the infant’s PFAS burden score with respect to mother’s parity. We measured PFAS using targeted and NTA methods in cord blood samples collected between 2003 and 2006 in the HOME Study (Cincinnati, Ohio). Using NTA, we putatively identified 42 PFAS in cord blood, 4 of which were also detected in targeted analysis. We summarized an infant’s overall prenatal exposure burden to PFAS using item response theory methods. We constructed two scores, one based on PFAS concentrations from targeted analysis (“PFAS exposure burden scores”), and one based on relative abundance from NTA (“PFAS-omics scores”). As expected, infants with multiparous mothers had significantly lower PFAS exposure burden scores than those with nulliparous mothers, but these disparities were not present when comparing their PFAS-omics scores. Our results show that infants are exposed to a wide range of PFAS, including perfluorinated chemicals, polyfluorinated chemicals, and fluorotelomers, before birth. Further, PFAS-focused NTA can help estimate total exposure to PFAS. Lastly, reported disparities in PFAS exposure burden across parity may depend on the panel of assessed PFAS and their half-lives.

Branched-chain fatty acids (BCFAs) are key components of the bacterial lipidome, playing a role in regulating membrane fluidity and permeability. In mammals, BCFAs occur at much lower concentrations, and their functions remain largely unexplored. Conventional lipid analysis methods, employing collision-induced dissociation (CID)-tandem mass spectrometry (MS/MS), often fail to locate methyl branching, as fragmentation rarely occurs around the branching site. Here, we introduce a bifunctional derivatization reagent, 1-(8-methoxy-5-quinolinyl) methanamine (MeO-QN), for pinpointing methyl branching in BCFAs with high sensitivity. MeO-QN enhances ionization efficiency of derivatized BCFAs in positive ion mode due to its quinoline moiety and serves as a precursor for radical-directed dissociation (RDD). Upon CID, the quinoline-O radical (QN-O•) is generated, which subsequently induces RDD along the fatty acyl chain and forms a characteristic 28 Da spacing indicative of the branching point. By integrating this MS/MS method with reversed-phase liquid chromatography, we have developed a sensitive analytical workflow, detecting BCFAs at sub-nM levels in mammalian samples. We detected the rarely reported n-5 methyl branched fatty acid (FA 16:0;12Me) in pooled human plasma. We also observed significantly reduced even-chain isobranched fatty acids in breast cancer cells (MDA-MB-468) versus normal breast cells (MCF-10A), suggesting its potential in cancer biomarker discovery.

Single-cell native mass spectrometry (MS) holds immense potential for highly sensitive in situ analysis of biological events within individual live cells. Herein, we present a significant advancement ...

The biotransformation of the dietary supplement ingredient 5α-hydroxy-laxogenin was investigated using human HepG2 cells, the rat and in silico using the online software Next-gen E-Resource for Drug ...

This study examines the isomeric composition of PEth reference materials and compares it with the natural variation in isomer distribution found in blood samples.

The objective of this study was to evaluate rapid evaporative ionization mass spectrometry (REIMS) as a rapid method to measure biochemical markers of…

Metabolic function plays a key role in our understanding of both biological and pathophysiological processes. Metabolism is a complex combination of intrinsic processes and environmental cues across a...

This work summarizes the criteria for a useful reagent for ion/ion proton transfer in an electrodynamic ion trap with specific emphasis on proton transfer to high mass multiply-charged analyte ions. A...

Background The rising incidence of Salmonella-induced diarrhea highlights the critical need for judicious antibiotic use to ensure effective treatment outcomes. Methods This study presents an inno...

This study presents a sustainable approach utilizing activated carbon derived from hazelnut shells as an adsorbent for the simultaneous quantitative analysis of 48 different volatile organic compounds...

Dissolved organic matter (DOM) cycling across the land-ocean continuum is highly complex, and our limited understanding of DOM molecular transformations hinders a full assessment of land-ocean connect...

Untargeted tandem mass spectrometry (MS/MS)-based metabolomics enable broad characterization of small molecules in complex samples, yet the majority of spectra in a typical experiment remain unannotated, limiting biological interpretation. Reference data-driven (RDD) metabolomics addresses this gap by contextualizing spectra through comparison to curated, metadata-annotated reference data sets, allowing inference of spectrum origins without requiring exact structural identification. Here, we present an open-source RDD metabolomics platform comprising a user-friendly web application and a Python software package that performs RDD analyses directly from molecular networking outputs generated by GNPS. The tools support visualization and statistical analysis of RDD results, including interactive bar plots, heat maps, principal component analysis, and Sankey diagrams. We illustrate the approach using a hierarchical reference data set of 3500 food items to derive dietary patterns from stool metabolomics data of omnivore and vegan participants. The analysis reveals clear dietary group separation, demonstrating how RDD metabolomics can extract biologically meaningful patterns from otherwise unannotated spectra. Thus, the RDD metabolomics platform removes technical barriers for the metabolomics community to adopting RDD analysis, with the functionality freely available at https://github.com/bittremieuxlab/gnps-rdd and https://gnps-rdd.bittremieuxlab.org/.

Here we present CleaveScope, a lightweight standalone software tool for rapid and flexible analysis of protease specificity using LC-MS/MS data. The program accepts XML output files from the Mascot se...

The graphical abstract summerizes the Investigation of the phytochemical profile and biological activities of the roots and flowers of D. tortuosa and D. triradiata. Plant materials were extracted us...

Exenatide and H-GLP-1 belong to the GLP-1 agonist class of potential therapeutic agents. A robust multienzyme peptide-mapping workflow combined with LC-HRMS/MS enables high-resolution sequence covera...

Background Recurrent implantation failure (RIF) is a significant clinical challenge in assisted reproduction, yet its underlying molecular mechanisms remain poorly understood. This study aimed to char...

Abstract. Seronegative rheumatoid arthritis (negRA) is difficult to diagnose due to the absence of rheumatoid factor and anticitrullinated peptide antibodi

Abstract. Diabetic kidney disease (DKD) is a complication of diabetes and the leading cause of kidney failure among diabetic patients. Unfortunately, it is

Cyanobacteria are highly taxonomically and ecologically diverse species that have survived for billions of years. Here, authors show key structural features have remained within their light harvesting...

Four famous freshwater fish in China are renowned for their high production among freshwater species and are much-prized as sought-after delicacies. H…

There is a growing need for rapid, low-cost analytical tools to screen water supplies for persistent contaminants. Due to their ubiquitous presence in the environment and their detrimental effects on ...

Purpose This study investigates metabolic profiles in follicular fluid of patients with endometriosis (EM), polycystic ovary syndrome (PCOS), tubal blockage (TB), and unexplained infertility (UEI), as...

In this study, we focused on the spatial distribution of metabolites in areca palm (Areca catechu L.) floral organs. Using spatial metabolomics, the composit...

Animal-derived foods intended for human consumption are susceptible to the accumulation of toxic substances, including pesticides. In Mexico and other countries, pork is one of the most consumed me...

This study demonstrates that breath analysis using PTR-TOF MS and machine learning accurately distinguishes early lung cancer from benign nodules in a large cohort, identifying key biomarkers like al...