Prostaglandins (PGs) are biologically active metabolites of arachidonic acid containing 20 carbon atoms, a cyclic moiety, and two side chains (A and B) in common. The bioassay of PGs requires high sensitivity because of their low concentration in tissues and blood and has usually been carried out by electrospray ionization tandem mass spectrometry (ESI-MS/MS) in the negative ion mode. Chemical derivatization of PG carboxylic acid groups to introduce positive charge-carrying groups is an established strategy to improve the sensitivity and selectivity of such assays. In this study, we exploited this approach for structural identification of a series of PGs using cholamine derivatization through an amidation reaction. However, we observed that collision-induced dissociation of these derivatives gave rise to unexpected product ions that we postulated were formed by unique long-range intramolecular reactions resulting in dehydration of the B chain accompanied by fragmentation of the A chain through an unusual Hofmann rearrangement. Evidence for the proposed mechanism is presented based on ESI-MS/MS and high resolution mass spectrometry studies of cholamine derivatives of PGE, PGE, PGD, PGI, and C-17 methyl deuterium-labeled limaprost. Graphical Abstract.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1007/s13361-018-2051-6 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Miniature Mass Spectrometry for Point-of-Care Testing the GPIIb/IIIa Inhibitor Tirofiban during Perioperative Period of Percutaneous Coronary Intervention.
ACS Omega
December 2024
Panvascular Diseases Research Center, The Quzhou Affiliated Hospital of Wenzhou Medical University, Quzhou People's Hospital, Quzhou 324000, China.
Article Synopsis
- The study developed a portable mass spectrometry technique for accurately measuring tirofiban drug concentrations in blood to enhance patient safety and treatment efficacy.
- The method identified a significant parent ion peak for tirofiban and optimized various parameters, achieving a limit of detection (LOD) and limit of quantification (LOQ) of 10.1 and 33.7 μg·L, respectively.
- Although the technique faced some challenges from blood sample matrix effects, it successfully detected tirofiban in 10 out of 12 clinical samples, demonstrating the need for further optimization and validation to boost sensitivity and stability.
The Site of Protonation Affects the Dissociation of Protonated α- and β-Pinene Ions.
Rapid Commun Mass Spectrom
March 2025
Department of Chemistry and Biomolecular Sciences, University of Ottawa, Ottawa, Canada.
Rationale: In electrospray ionization and atmospheric pressure chemical ionization, the protonation site directly guides the ion's dissociation. But what if the site of protonation is ambiguous? In this study, we explored the unimolecular reactions of protonated α- and β-pinene ions with a combination of tandem mass spectrometry and theory. Each has multiple potential protonation sites that influence their chemistry.
View Article and Find Full Text PDFEnergy-Resolved Mass Spectrometry and Mid-Infrared Spectroscopy for Purity Assessment of a Synthetic Peptide Cyclised by Intramolecular Huisgen Click Chemistry.
Methods Protoc
December 2024
Univ Brest, CEMCA, CNRS, UMR 6521, 29238 Brest, France.
Cyclic peptides have higher stability and better properties as therapeutic agents than their linear peptide analogues. Consequently, intramolecular click chemistry is becoming an increasingly popular method for the synthesis of cyclic peptides from their isomeric linear peptides. However, assessing the purity of these cyclic peptides by mass spectrometry is a significant challenge, as the linear and cyclic peptides have identical masses.
View Article and Find Full Text PDFGoniodomic Acid, a Transient Oxirane Intermediate in the Conversion of the Macrolide Algal Toxin Goniodomin A to Seco Acids.
Chem Res Toxicol
December 2024
Department of Chemistry, Vanderbilt University, Nashville, Tennessee 37235, United States.
The algal macrolide goniodomin A (GDA) undergoes ring-cleavage under unusually mild, alkaline conditions to form mixtures of stereoisomers of seco acids GDA-sa and iso-GDA-sa. In the primary fragmentation pathway, opening of the macrolide ring occurs by displacement of the carboxyl group by a base-catalyzed attack of the C32 hemiketal hydroxy group on C31, yielding an oxirane-carboxylic acid, named goniodomic acid. The oxirane ring is unstable, undergoing solvolytic opening to form mainly GDA-sa.
View Article and Find Full Text PDFDirect Implementation of MS Using Frequency Scanning Collision Induced Dissociation in a Digital Ion Trap Mass Spectrometer.
J Am Soc Mass Spectrom
December 2024
School of Electronic and Information Engineering, Soochow University, Suzhou 215006, China.
Tandem mass spectrometry (MS) is one of the most effective methods to obtain the structures of organic molecules, enabling the observation of multigenerational ion fragments. Collision-induced dissociation (CID) is currently the most mature technique for mass spectrometry analysis. Ion trap mass spectrometry (ITMS) is favored for on-site detection field, due to its ability of MS analysis with a single trap and its small size.
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!