A large fraction of ions observed in electrospray liquid chromatography-mass spectrometry (LC-ESI-MS) experiments of biological samples remain unidentified. One of the main reasons for this is that spectral libraries of pure compounds fail to account for the complexity of the metabolite profiling of complex materials. Recently, the NIST Mass Spectrometry Data Center has been developing a novel type of searchable mass spectral library that includes all recurrent unidentified spectra found in the sample profile. These libraries, in conjunction with the NIST tandem mass spectral library, allow analysts to explore most of the chemical space accessible to LC-MS analysis. In this work, we demonstrate how these libraries can provide a reliable fingerprint of the material by applying them to a variety of urine samples, including an extremely altered urine from cancer patients undergoing total body irradiation. The same workflow is applicable to any other biological fluid. The selected class of acylcarnitines is examined in detail, and derived libraries and related software are freely available. They are intended to serve as online resources for continuing community review and improvement.
Download full-text PDF |
Source |
|---|---|
| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6839828 | PMC |
| http://dx.doi.org/10.1021/acs.analchem.9b02977 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Building a near-infrared (NIR) soil spectral dataset and predictive machine learning models using a handheld NIR spectrophotometer.
Data Brief
February 2025
Woodwell Climate Research Center, 149 Woods Hole Rd., Falmouth, MA, 02540, United States.
This near-infrared spectral dataset consists of 2,106 diverse mineral soil samples scanned, on average, on six different units of the same low-cost commercially available handheld spectrophotometer. Most soil samples were selected from the USDA NRCS National Soil Survey Center-Kellogg Soil Survey Laboratory (NSSC-KSSL) soil archives to represent the diversity of mineral soils (0-30 cm) found in the United States, while 90 samples were selected from Ghana, Kenya, and Nigeria to represent available African soils in the same archive. All scanning was performed on dried and sieved (<2 mm) soil samples.
View Article and Find Full Text PDFNew Library-Based Methods for Nontargeted Compound Identification by GC-EI-MS.
J Am Soc Mass Spectrom
January 2025
Biomolecular Measurement Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899-8362, United States.
While gas chromatography mass spectrometry (GC-MS) has long been used to identify compounds in complex mixtures, this process is often subjective and time-consuming and leaves a large fraction of seemingly good-quality spectra unidentified. In this work, we describe a set of new mass spectral library-based methods to assist compound identification in complex mixtures. These methods employ mass spectral uniqueness and compound ubiquity of library entries alongside noise reduction and automated comparison of retention indices to library compounds.
View Article and Find Full Text PDFOpen Soil Spectral Library (OSSL): Building reproducible soil calibration models through open development and community engagement.
PLoS One
January 2025
Woodwell Climate Research Center, Falmouth, MA, United States of America.
Soil spectroscopy is a widely used method for estimating soil properties that are important to environmental and agricultural monitoring. However, a bottleneck to its more widespread adoption is the need for establishing large reference datasets for training machine learning (ML) models, which are called soil spectral libraries (SSLs). Similarly, the prediction capacity of new samples is also subject to the number and diversity of soil types and conditions represented in the SSLs.
View Article and Find Full Text PDFTransformative knowledge of polar polycyclic aromatic hydrocarbons via high-resolution mass spectrometry.
Sci Total Environ
January 2025
Marine Toxicology, Institute of Marine Research, Bergen, Norway.
Polycyclic aromatic hydrocarbons (PAHs) are toxic contaminants with a widespread presence in diverse environmental contexts. Transformation processes of PAHs via degradation and biotransformation have parallels in humans, animals, plants, fungi, and bacteria. Mapping the transformation products of PAHs is therefore crucial for assessing their toxicological impact and developing effective monitoring strategies.
View Article and Find Full Text PDFDeveloping Chemical Signatures for Categories of Household Consumer Products Using Suspect Screening Analysis.
Environ Sci Technol
January 2025
Center for Computational Toxicology and Exposure, Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina 27711, United States.
Consumer products are a major source of chemicals that may pose a health risk. It is important to understand what chemicals are in these products to evaluate risk and assess new products for uncommon ingredients. Suspect screening analysis (SSA) using two-dimensional gas chromatography-high-resolution-time-of-flight/mass spectrometry (GCxGC-HR-TOF/MS) was applied to 92 consumer products from 5 categories.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!