Non-targeted small molecule screening methods are used to analyze samples for potential compounds of interest without focusing on specific molecular species. There is great interest in these methods for metabolomic, environmental, forensic, and food safety applications, among others, to determine compounds that are responsible for a particular disease state or the presence of a harmful compound. In order for non-targeted analyses to become standardized and routine, best practices for sample preparation, data collection, and data analysis must be determined. This work focuses on optimizing specific aspects of a non-targeted workflow that utilizes high-resolution mass spectrometry using an Orbitrap instrument coupled to liquid chromatography. Sample preparation, liquid chromatography gradient length, and mass spectrometry resolving power and ionization modes were investigated to determine optimal conditions for detecting and extracting compounds from the data that cover broad molecular and polarity ranges. Infant rice cereal, orange juice, and yogurt with spiked standards were analyzed; food is inherently challenging to analyze due in part to sample complexity and diversity. Of the conditions tested, optimal conditions included a generic sample extraction using acetonitrile, water, and formic acid, a 25 min chromatographic gradient, collecting data in both positive and negative ion modes, and using 70 k resolving power. There are of course tradeoffs associated with each of these options that will be described in detail so that the appropriate conditions can be chosen for the desired application.
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http://dx.doi.org/10.1016/j.aca.2019.03.032 | DOI Listing |
Crit Care
January 2025
Department of Critical Care Medicine, Cumming School of Medicine, Health Research Innovation Center (HRIC), University of Calgary, Room 4C64, 3280 Hospital Drive N.W., Calgary, AB, T2N 4Z6, Canada.
Background: Traumatic brain injury (TBI) is a major public health concern worldwide, contributing to high rates of injury-related death and disability. Severe traumatic brain injury (sTBI), although it accounts for only 10% of all TBI cases, results in a mortality rate of 30-40% and a significant burden of disability in those that survive. This study explored the potential of metabolomics in the diagnosis of sTBI and explored the potential of metabolomics to examine probable primary and secondary brain injury in sTBI.
View Article and Find Full Text PDFSci Rep
January 2025
Department of Biotechnology, Jožef Stefan Institute, Ljubljana, Slovenia.
Extracellular vesicles (EVs) are nanosized lipid bilayer particles released by various cellular organisms that carry an array of bioactive molecules. EVs have diagnostic potential, as they play a role in intercellular interspecies communication, and could be applied in drug delivery. In contrast to mammalian cell-derived EVs, the study of EVs from bacteria, particularly Gram-positive bacteria, received less research attention.
View Article and Find Full Text PDFNature
January 2025
Laboratory for Biological Geochemistry, School of Architecture, Civil and Environmental Engineering, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland.
Increasing soil salinity causes significant crop losses globally; therefore, understanding plant responses to salt (sodium) stress is of high importance. Plants avoid sodium toxicity through subcellular compartmentation by intricate processes involving a high level of elemental interdependence. Current technologies to visualize sodium, in particular, together with other elements, are either indirect or lack in resolution.
View Article and Find Full Text PDFSci Rep
January 2025
Department of Obstetrics and Gynecology, Baylor College of Medicine, Texas Children's Hospital, Houston, TX, USA.
Prenatal sonographic diagnosis of congenital heart disease (CHD) can lead to improved morbidity and mortality. However, the diagnostic accuracy of ultrasound, the sole prenatal screening tool, remains limited. Failed prenatal or early newborn detection of cyanotic CHD (CCHD) can have disastrous consequences.
View Article and Find Full Text PDFCommun Chem
January 2025
Michael Barber Centre for Collaborative Mass Spectrometry, Manchester Institute of Biotechnology, Manchester, UK.
The transcription factor p53 is exquisitely sensitive and selective to a broad variety of cellular environments. Several studies have reported that oxidative stress weakens the p53-DNA binding affinity for certain promoters depending on the oxidation mechanism. Despite this body of work, the precise mechanisms by which the physiologically relevant DNA-p53 tetramer complex senses cellular stresses caused by HO are still unknown.
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