bims-metlip 2024-12-22 papers

bims-metlip

Biomed News

on Methods and protocols in metabolomics and lipidomics

Issue of 2024–12–22
25 papers selected by
Sofia Costa, Matterworks

Development, validation, and clinical application of LC-MS/MS method for simultaneous determination of ibrutinib, zanubrutinib, orelabrutinib, acalabrutinib, and their active metabolites in patients with B-cell lymphoma.
Quantification of gimeracil, tegafur, and 5-FU in human plasma via LC-MS/MS with a simplified pretreatment using flow-through extraction.
Quantification of ∆9-tetrahydrocannabinol (THC), 11-OH-THC, THC-COOH, hexahydrocannabinol and cannabidiol in human plasma and blood by liquid chromatography-tandem mass spectrometry.
Diazonium-based derivatization for enhanced detection of phosphorylated metabolites by LC-MS in cells.
Introducing "Identification Probability" for Automated and Transferable Assessment of Metabolite Identification Confidence in Metabolomics and Related Studies.
DNEA: an R package for fast and versatile data-driven network analysis of metabolomics data.
Sensitive LC-MS/MS Assay for Total Testosterone Quantification on Unit Resolution and High-Resolution Instruments.
Gas Chromatography-Tandem Mass Spectrometry Method for Analyses of Iodoform and Diiodomethane in Multiple Biological Matrices from Dairy Cattle.
Quantification of Vactosertib an Inhibitor of TGFBR1 by LC-MS/MS in Rat Plasma and Its Pharmacokinetic Profiling.
Rapid LC-MS/MS Evaluation of Collagen and Elastin Crosslinks in Human and Mouse Lung Tissue with a Novel Bioanalytical Surrogate Matrix Approach.
Bromine signature coded derivatization LC-MS for specific profiling of carboxyl or carbonyl-containing metabolites in Mycoplasma pneumoniae infection.
Differential Mobility Spectrometry Acoustic Ejection Mass Spectrometer System for Screening Isomerization-Mediating Enzyme Drug Targets.
Method for determination of cytisine in post-mortem biological matrices and its application to two forensic cases.
A-SIMA/A-MAP: a comprehensive toolkit for NMR-based metabolomics analysis.
Development of a Matrix-Assisted Laser Desorption Ionization High Resolution Mass Spectrometry Method for the Quantification of Camalexin and Scopoletin in Arabidopsis thaliana.
Isomer Differentiation by UHPLC-Q-Exactive-Orbitrap MS led to Enhanced Identification of Daphnane Diterpenoids in Daphne tangutica.
Development and validation of a quantification method for direct oral anticoagulants from capillary blood using volumetric absorptive microsampling and online SPE-LC-MS.
Development of a Tandem Mass Spectral Library for the Detection of Triterpenoids in Plant Metabolome Based on Reference Standards.
Perspectives of Quantitative GC-MS, LC-MS, and ICP-MS in the Clinical Medicine Science-The Role of Analytical Chemistry.
Multi-sample analytical workflow for the determination of isoprostanes in oral fluid: A new tool for non-invasive evaluation of oxidative stress.
[Validation Study of LC-MS/MS for Paralytic Shellfish Toxins and Tetrodotoxin in Scallops].
A simple HPLC method for the determination of plasma progesterone levels in the third trimester of human pregnancy.
Post-column denaturation-assisted hydrophobic interaction chromatography-mass spectrometry for rapid and in-depth characterization of positional isomers in cysteine-based antibody-drug conjugates.
Establishment of a Mass Spectrometric Fingerprint of the Most Common Phytocannabinoids in Electrospray Ionization in Positive Ion Mode.
Transcending Resolution Limits in HPLC and Diffusion NMR.

Anal Bioanal Chem. 2024 Dec 19.

Development, validation, and clinical application of LC-MS/MS method for simultaneous determination of ibrutinib, zanubrutinib, orelabrutinib, acalabrutinib, and their active metabolites in patients with B-cell lymphoma.

Dan Jiang, Zaiwei Song, Yi Ma, Xu Zhang, Hao Bing, Xin Xiong, Yang Hu, Fei Dong, Rongsheng Zhao.

  Bruton's tyrosine kinase inhibitors (BTKis) exhibit significant interindividual pharmacokinetics, making therapeutic drug monitoring (TDM) a promising approach for personalized therapy. However, simultaneous quantification of multiple BTKis poses technical challenges. A unified protocol for BTKis detection would be clinically desirable. Herein, we developed and validated a novel LC-MS/MS method for the simultaneous analysis of four BTKis including ibrutinib (IBR), zanubrutinib (ZAN), orelabrutinib (ORE), and acalabrutinib (ACB) and active metabolite of IBR and ACB (DIH and ACBM, respectively) in human plasma. The samples were prepared by liquid-liquid extraction using tert-butyl methyl ether. Ibrutinb-d4 (IS) was used as an internal standard. Chromatographic separation was obtained on an XBridge C18 column and connected to an LC-30AD system coupled to an API 4000+ mass spectrometer. The mobile phase comprised 10 mM ammonium acetate containing 0.1% formic acid and acetonitrile containing 0.1% formic acid. The optimized multiple reaction monitoring transitions of m/z 441.4 → 138.3, 475.4 → 304.2, 472.5 → 455.5, 428.3 → 411.5, 466.1 → 372.2, 482.2 → 388.4, and 445.5 → 142.5 were selected to inspect IBR, DIH, ZAN, ORE, ACB, ACBM, and IS, respectively. The method exhibited linearity from 1 to 1000 ng/mL (r > 0.99) for all analytes, with intra-day and inter-day precision of 1.8 to 9.7% and accuracy below 15%. Recovery ranged from 90.4 to 113.6%, and matrix effect varied from 89.3 to 111.0%. All compounds demonstrated stability under relevant conditions. Application of the method to 57 blood samples from 18 patients demonstrated high interpatient variability, with ORE plasma concentrations ranging from 25.6 to 89.9%. The validated LC-MS/MS method provides a feasible, specific, and rapid approach for quantification of BTKis in clinical settings. Simultaneous determination of four BTKis and their metabolites in a single extraction process and chromatographic run reduces analysis time, cost, and resources. The observed variability among individuals highlights the value of TDM for personalized treatment.

Keywords:  B-cell lymphoma; BTK inhibitors; LC-MS/MS; Therapeutic drug monitoring

DOI:  https://doi.org/10.1007/s00216-024-05701-2
J Chromatogr B Analyt Technol Biomed Life Sci. 2024 Dec 07. pii: S1570-0232(24)00433-1. [Epub ahead of print]1251 124424

Quantification of gimeracil, tegafur, and 5-FU in human plasma via LC-MS/MS with a simplified pretreatment using flow-through extraction.

Motozumi Ando, Norio Watanabe, Riko Seike, Saori Gocho, Shoko Maeda, Masami Inagaki, Masami Kawahara.

  Gimeracil, a component in S-1 (an oral anticancer agent comprising tegafur, a prodrug of 5-fluorouracil (5-FU), potassium oxonate, and gimeracil), inhibits metabolic enzymes, thereby impeding 5-FU degradation. Therefore, the blood level of gimeracil is closely associated with the disposition of 5-FU, and quantification of gimeracil can provide important information if a case shows an inappropriate 5-FU blood concentration. Nevertheless, methods for quantifying gimeracil in human plasma are rarely reported. Herein, we aimed to develop a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for quantifying gimeracil, in addition to tegafur and 5-FU, levels in human plasma using a clinically applicable simplified pretreatment process and faster elution time. Hence, an acetamide-functionalized monolith silica disk-packed spin column was used to extract gimeracil and internal standard (IS; nicotinamide), whereas diatomaceous earth-based solid phase for liquid-liquid extraction was used to extract tegafur, 5-FU, and IS (5-chlorouracil) from plasma. Each extract was analyzed within 4 min of elution via LC-MS/MS using a shared LC column and mobile phase. Accuracy and precision analyses indicated lower limits of quantification of 5, 10, and 2 ng/mL for gimeracil, tegafur, and 5-FU, respectively. The calibration curves showed good linearity between 5 and 500 ng/mL for gimeracil, 10 and 5000 ng/mL for tegafur, and 2 and 1000 ng/mL for 5-FU. We confirmed that the levels of all analytes in the plasma of patients with cancer undergoing S-1-inclusive therapy were within the calibration range for each analyte. Thus, this newly developed quantification method is likely to be useful for optimization of S-1 therapy.

Keywords:  5-fluorouracil; Gimeracil; Human plasma; Tandem mass spectrometry; Tegafur; Therapeutic drug monitoring

DOI:  https://doi.org/10.1016/j.jchromb.2024.124424
J Anal Toxicol. 2024 Dec 05. pii: bkae094. [Epub ahead of print]

Quantification of ∆9-tetrahydrocannabinol (THC), 11-OH-THC, THC-COOH, hexahydrocannabinol and cannabidiol in human plasma and blood by liquid chromatography-tandem mass spectrometry.

Marion Pavlic, Carolin Innerhofer, Florian Pitterl.

  Ongoing legalization of cannabis for recreational use contributes to increasing numbers not only of incidents of driving under the influence, but within all forensic fields. In addition, newly emerging cannabinoids such as hexahydrocannabinol (HHC) and the increasing use of cannabidiol (CBD) products have to be addressed. The aims of this study were first to extend laboratory analysis capacity for the "established" cannabinoid ∆9-tetrahydrocannabinol (THC) and its metabolites 11-OH-THC and THC-COOH in human plasma/blood, and second to develop analytical procedures concerning HHC and CBD. An LC-MS/MS method based on the available (low-end) instrumentation was used. Samples (250 µL) were prepared by protein precipitation and solid phase extraction. Chromatographic separation was achieved on a reversed-phase C18 column within 15 min. Detection was performed on a 3200 QTRAP instrument (Sciex) in positive multiple reaction monitoring (MRM) mode. Matrix matched six-point calibrations were generated applying deuterated internal standards for all analytes except HHC. The method was fully validated according to GTFCh guidelines. Linear ranges were 0.5-25 µg/L for THC, 11-OH-THC, HHC and CBD, and 2.0-100 µg/L for THC-COOH, respectively. Limits of detection and limits of quantification were 0.5 and 1.0 µg/L (THC, 11-OH-THC, HHC, CBD), and 2.0 and 4.0 µg/L (THC-COOH). Applicability of plasma calibrations to blood samples was demonstrated. Acceptance criteria for intra- and inter-day accuracy, precision, extraction efficiency and matrix effects were met. No interfering signals were detected for more than 60 pharmaceutical compounds. The presented method is sensitive, specific, easy to handle and does not require high-end equipment. Since its implementation and accreditation according to ISO 17025, the method has proven to be fit for purpose not only in DUID cases but also within post-mortem samples. Furthermore, the design of the method allows for an uncomplicated extension to further cannabinoids if required.

Keywords:  CBD; DUID; HHC; LC–MS/MS; THC; post mortem cases; quantification

DOI:  https://doi.org/10.1093/jat/bkae094
J Pharm Biomed Anal. 2024 Dec 16. pii: S0731-7085(24)00684-8. [Epub ahead of print]255 116642

Diazonium-based derivatization for enhanced detection of phosphorylated metabolites by LC-MS in cells.

Yikang Wang, Feifei Lin, Guozheng Zhu, Xiaoxue Zhou, Youhong Hu, Jia Liu.

  Phosphorylated small molecule metabolites play crucial roles in physiological processes such as glycogen metabolism and inflammation regulation. However, their high polarity, structural similarity, poor chromatographic separation, and weak mass spectrometric signals make their accurate quantification challenging, thereby hindering the study of related metabolic mechanisms and diseases. To address these challenges, we developed a novel derivatization reagent, DMQX (5-diazomethane quinoxaline), and combined it with liquid chromatography-mass spectrometry (LC-MS). This approach achieved baseline separation of five groups of isomers and enabled the quantification of 24 phosphorylated metabolites, providing comprehensive coverage of these metabolites in biological pathways. We applied this method to quantify 21 endogenous phosphorylated metabolites in HepG2 cells with and without vesicular stomatitis virus infection, demonstrating the potential of this analytical approach for advancing the study of metabolic mechanisms through quantitative analysis of phosphorylated metabolites in biological samples.

Keywords:  Chromatographic separation; Derivatization; LC-MS; Phosphorylated metabolite; Quantitative analysis

DOI:  https://doi.org/10.1016/j.jpba.2024.116642
Anal Chem. 2024 Dec 19.

Introducing "Identification Probability" for Automated and Transferable Assessment of Metabolite Identification Confidence in Metabolomics and Related Studies.

Thomas O Metz, Christine H Chang, Vasuk Gautam, Afia Anjum, Siyang Tian, Fei Wang, Sean M Colby, Jamie R Nunez, Madison R Blumer, Arthur S Edison, Oliver Fiehn, Dean P Jones, Shuzhao Li, Edward T Morgan, Gary J Patti, Dylan H Ross, Madelyn R Shapiro, Antony J Williams, David S Wishart.

Methods for assessing compound identification confidence in metabolomics and related studies have been debated and actively researched for the past two decades. The earliest effort in 2007 focused primarily on mass spectrometry and nuclear magnetic resonance spectroscopy and resulted in four recommended levels of metabolite identification confidence─the Metabolite Standards Initiative (MSI) Levels. In 2014, the original MSI Levels were expanded to five levels (including two sublevels) to facilitate communication of compound identification confidence in high resolution mass spectrometry studies. Further refinement in identification levels have occurred, for example to accommodate use of ion mobility spectrometry in metabolomics workflows, and alternate approaches to communicate compound identification confidence also have been developed based on identification points schema. However, neither qualitative levels of identification confidence nor quantitative scoring systems address the degree of ambiguity in compound identifications in the context of the chemical space being considered. Neither are they easily automated nor transferable between analytical platforms. In this perspective, we propose that the metabolomics and related communities consider identification probability as an approach for automated and transferable assessment of compound identification and ambiguity in metabolomics and related studies. Identification probability is defined simply as 1/N, where N is the number of compounds in a database that matches an experimentally measured molecule within user-defined measurement precision(s), for example mass measurement or retention time accuracy, etc. We demonstrate the utility of identification probability in an in silico analysis of multiproperty reference libraries constructed from a subset of the Human Metabolome Database and computational property predictions, provide guidance to the community in transparent implementation of the concept, and invite the community to further evaluate this concept in parallel with their current preferred methods for assessing metabolite identification confidence.

DOI: https://doi.org/10.1021/acs.analchem.4c04060
BMC Bioinformatics. 2024 Dec 18. 25(1): 383

DNEA: an R package for fast and versatile data-driven network analysis of metabolomics data.

Christopher Patsalis, Gayatri Iyer, Marci Brandenburg, Alla Karnovsky, George Michailidis.

   BACKGROUND: Metabolomics is a high-throughput technology that measures small molecule metabolites in cells, tissues or biofluids. Analysis of metabolomics data is a multi-step process that involves data processing, quality control and normalization, followed by statistical and bioinformatics analysis. The latter step often involves pathway analysis to aid biological interpretation of the data. This approach is limited to endogenous metabolites that can be readily mapped to metabolic pathways. An alternative to pathway analysis that can be used for any classes of metabolites, including unknown compounds that are ubiquitous in untargeted metabolomics data, involves defining metabolite-metabolite interactions using experimental data. Our group has developed several network-based methods that use partial correlations of experimentally determined metabolite measurements. These were implemented in CorrelationCalculator and Filigree, two software tools for the analysis of metabolomics data we developed previously. The latter tool implements the Differential Network Enrichment Analysis (DNEA) algorithm. This analysis is useful for building differential networks from metabolomics data containing two experimental groups and identifying differentially enriched metabolic modules. While Filigree is a user-friendly tool, it has certain limitations when used for the analysis of large-scale metabolomics datasets.
RESULTS: We developed the DNEA R package for the data-driven network analysis of metabolomics data. We present the DNEA workflow and functionality, algorithm enhancements implemented with respect to the package's predecessor, Filigree, and discuss best practices for analyses. We tested the performance of the DNEA R package and illustrated its features using publicly available metabolomics data from the environmental determinants of diabetes in the young. To our knowledge, this package is the only publicly available tool designed for the construction of biological networks and subsequent enrichment testing for datasets containing exogenous, secondary, and unknown compounds. This greatly expands the scope of traditional enrichment analysis tools that can be used to analyze a relatively small set of well-annotated metabolites.
CONCLUSIONS: The DNEA R package is a more flexible and powerful implementation of our previously published software tool, Filigree. The modular structure of the package, along with the parallel processing framework built into the most computationally extensive steps of the algorithm, make it a powerful tool for the analysis of large and complex metabolomics datasets.

Keywords:  Enrichment analysis; Metabolomics; Network analysis; Network visualization; Partial correlation; Pathway analysis

DOI:  https://doi.org/10.1186/s12859-024-05994-1
J Clin Med. 2024 Nov 22. pii: 7056. [Epub ahead of print]13(23):

Sensitive LC-MS/MS Assay for Total Testosterone Quantification on Unit Resolution and High-Resolution Instruments.

Jill K Wolken, Meghan M Peterson, Wenjing Cao, Keith Challoner, Zhicheng Jin.

  Background: Testosterone is an androgenic hormone that plays important roles in both males and females. The circulating levels of total testosterone vary from 1 to 1480 ng/dL. High-throughput immunoassays often lack accuracy in lower concentration ranges (below 100 ng/dL), particularly when used for females or children. To address this limitation, we developed a total testosterone LC-MS/MS assay on three instruments. Methods: Sample preparation began with the dilution and conditioning of 200 µL of serum. A supported liquid extraction cartridge was used to extract the analyte from biological matrices. Chromatographic separation was achieved using a C18 column with a runtime of 5 min per sample. This assay was validated on a Triple Quad 6500 and an API 4500 instrument. Results: Method validation was carried out according to the CLSI C62-ED2 guideline and our hospital protocol. The within-day coefficient of variation (CV) was less than 10% and the between-day CV was less than 15%. The assay had a limit of quantitation of 0.5 ng/dL with an analyte measure range of 2-1200 ng/dL. A comparison using Deming regression and Bland-Altman plots showed that this assay correlated well with a reference method. The results from the API 4500 and an Orbitrap were consistent with those from the TQ 6500. Both serum-separator tubes (BD) and serum-activator tubes were found to be suitable. Conclusions: We successfully developed and validated a robust total testosterone LC-MS/MS assay for routine clinical testing. This assay was harmonized across two triple quadrupole instruments and one high-resolution mass spectrometer.

Keywords:  assay harmonization; high-resolution mass spectrometry; multiple reaction monitoring; parallel reaction monitoring; testosterone

DOI:  https://doi.org/10.3390/jcm13237056
J Agric Food Chem. 2024 Dec 18.

Gas Chromatography-Tandem Mass Spectrometry Method for Analyses of Iodoform and Diiodomethane in Multiple Biological Matrices from Dairy Cattle.

Marie Rønn, Mette Olaf Nielsen, Natalja P Nørskov.

  A quantitative method was developed and validated to analyze iodoform and its potential metabolite, diiodomethane, in biological fluids from dairy cows, including rumen fluid, duodenal fluid, blood serum, milk, and urine, using liquid-liquid extraction (LLE) and GC-MS/MS. The method showed no matrix effects across different samples, recoveries of spiked samples between 70 and 120%, and relative standard deviations (RSD%) ranging from 0.7 to 14%. Inter- and intravariations in quality control samples were within 3.1-12.3%, with the highest variation noted in iodoform spiking. Normalized internal standard (IS) and matrix factor (MF) calculations confirmed the suitability of diiodomethane-d2 as an internal standard for quantifying both compounds across different matrices. These results validate the method's application for ADME (absorption, distribution, metabolism, and excretion) studies, enabling the investigation of iodoform digestion, metabolism, and excretion in dairy cattle.

Keywords:  biological samples; gas chromatography; iodoform and diiodomethane quantification; liquid−liquid extraction; method development

DOI:  https://doi.org/10.1021/acs.jafc.4c08419
Biomed Chromatogr. 2025 Jan;39(1): e6057

Quantification of Vactosertib an Inhibitor of TGFBR1 by LC-MS/MS in Rat Plasma and Its Pharmacokinetic Profiling.

Rajesh Kumar Boggavarapu, Jithendra Chimakurthy, Sathish Kumar Konidala.

  Vactosertib, an inhibitor of transforming growth factor β-receptor type-1 (TGFBR1) effective in preventing tumor cell proliferation, is approved for treating various cancers by FDA. The literature revealed that no LC-MS/MS method was reported for the quantification of vactosertib. To develop a validated LC-MS/MS method for the quantification of vactosertib in rat plasma, vactosertib and cabozantinib (internal standard [IS]) were detected using Waters LC-MS/MS system in MRM positive ionization mode, with a mixture of 0.2% formic acid and acetonitrile (70:30, v/v) on an Agilent XDB C18 (50 × 2.1 mm, 5 μm) column at a flow rate of 0.8 mL/min. The method was validated in accordance with M10 bioanalytical method validation USFDA guidelines and applied for the determination of pharmacokinetic parameters in rat plasma. The analytes were detected at m/z 400.23 → 289.19 and m/z 502.13 → 323.07 for vactosertib, and IS, respectively. The method demonstrated a sensitivity of 1.0 ng/mL, linearity ranging from 1.0 to 1000.0 ng/mL, an r2 of 0.999, accuracy ranged between 91.60% and 100.70%, and the drug was found to be stable across all freeze-thaw cycles. The results indicated that the method was selective, accurate, and validated for quantification of vactosertib in biological fluids and pharmacokinetic profiling of vactosertib.

Keywords:  LC–MS/MS; TGFBR1; cabozantinib; serine inhibitor; tumor; vactosertib

DOI:  https://doi.org/10.1002/bmc.6057
Int J Mol Sci. 2024 Dec 04. pii: 13026. [Epub ahead of print]25(23):

Rapid LC-MS/MS Evaluation of Collagen and Elastin Crosslinks in Human and Mouse Lung Tissue with a Novel Bioanalytical Surrogate Matrix Approach.

Sarah M Lloyd, Elizabeth J Sande, Kenneth Ruterbories, Stephen P O'Brien, Yue-Ting Wang, Lucy A Phillips, Tracy L Carr, Meghan Clements, Lisa A Hazelwood, Yu Tian, Yupeng He, Qin C Ji.

  Alterations to post-translational crosslinking modifications in the extracellular matrix (ECM) are known to drive the pathogenesis of fibrotic diseases, including idiopathic pulmonary fibrosis (IPF). Thus, the methodology for measuring crosslinking dynamics is valuable for understanding disease progression. The existing crosslinking analysis sample preparation and liquid chromatography tandem mass spectrometry (LC-MS/MS) methods are typically labor-intensive and time-consuming which limits throughput. We, therefore, developed a rapid approach minimizing specialized equipment and hands-on time. The LC-MS/MS sample analysis time was reduced to two minutes per sample. We then improved the analytical integrity of the method by developing a novel surrogate matrix approach for the dihydroxylysinonorleucine (DHLNL) crosslink. By modifying sample preparation, we prepared a tissue-based surrogate matrix with undetectable levels of endogenous DHLNL, providing a strategy for quantifying this crosslink with a more relevant standard matrix. We then applied this rapid methodology to evaluating crosslinking in lung fibrosis. We showed an increase in DHLNL in human IPF lung relative to healthy donors, as well as in a fibrotic mouse model. Finally, we demonstrated that this increase in DHLNL could be mitigated with an anti-fibrotic compound, suggesting that this assay has potential for evaluating pharmaceutical compound efficacy.

Keywords:  LC-MS/MS; bioanalysis; collagen; crosslinking; elastin; fibrosis; lung; surrogate matrix

DOI:  https://doi.org/10.3390/ijms252313026
Talanta. 2024 Dec 06. pii: S0039-9140(24)01727-2. [Epub ahead of print]285 127345

Bromine signature coded derivatization LC-MS for specific profiling of carboxyl or carbonyl-containing metabolites in Mycoplasma pneumoniae infection.

Jie Han, Qinyan Yang, Zheng Zhi, Na Li, Jian-Lin Wu.

  Carboxyl or carbonyl-containing metabolites (CoCCMs) are widely distributed in biological samples. Global profiling of CoCCMs is essential for ascertaining specific functions of metabolites and their potential physiological roles in biogenic activities. However, simultaneous determination of these compounds is hampered by poor ionization efficiency, vast polarity differences, wide discrepancy of concentration ranges. Herein, a novel bromine isotope derivatization reagent 5-bromo-2- hydrazinopyridine was employed for CoCCMs profiling by liquid chromatography-mass spectrometry (LC-MS). This method enabled rapid derivatization of 44 CoCCMs under mild conditions. Enhanced separation efficiencies, detection sensitivities, and distinctive MS fragmentation characteristics were observed. Furthermore, this method was demonstrated to be efficient in revealing metabolic alternations, and abnormal serum levels of 6-keto-PGF1α, 12(S)-HHTrE, 15(S)-HEPE and N-acetyl tryptophan were disclosed for the first time in Mycoplasma pneumoniae (MP) infectious patients. Finally, based on the distinctive 2 Da differences of molecular ion peak pairs with almost 1:1 intensity ratio originated from 79Br and 81Br isotopes, an MS-DIAL and Python assisted MS1 isotope screening-MS2 fragments characterization combination strategy was developed for rapid screening, classification, and identification of detected CoCCMs. A total of 1069 CoCCMs were detected, of which 198 CoCCMs were identified in untargeted analysis. Statistical analysis revealed altered metabolic pathways, while glutamic acid, oxoglutaric acid, succinic acid, pyruvic acid, glyceric acid, and glycine were selected as potential biomarkers of MP infection. This bromine signature coded derivatization-LC-MS approach was proved to be a valuable tool for global probing of CoCCMs in biological samples with high sensitivity and broad coverage.

Keywords:  Bromine coded derivatization; Carboxyl or carbonyl-containing metabolites; Liquid chromatography-mass spectrometry; Mycoplasma pneumoniae infection

DOI:  https://doi.org/10.1016/j.talanta.2024.127345
Anal Chem. 2024 Dec 19.

Differential Mobility Spectrometry Acoustic Ejection Mass Spectrometer System for Screening Isomerization-Mediating Enzyme Drug Targets.

Samad Bazargan, Patricia Dranchak, Chang Liu, James Inglese, John Janiszewski, Bradley B Schneider, Thomas R Covey.

We report the first implementation of ion mobility mass spectrometry combined with an ultrahigh throughput sample introduction technology for high-throughput screening (HTS). The system integrates differential mobility spectrometry (DMS) with acoustic ejection mass spectrometry (AEMS), termed DAEMS, enabling the simultaneous quantitation of structural isomers that are the substrates and products of isomerase-mediated reactions in intermediary metabolism. We demonstrate this potential by comparing DAEMS to a luminescence assay for the isoform of phosphoglycerate mutase (iPGM) distinctively present in pathogens, offering an opportunity as a drug target for a variety of microbial and parasite borne diseases. The metabolome consists of many structural isomers that require for separation a mobility resolving power of more than 300. Resolving powers measured in collision cross-section space of 1588 and 1948 for 2- and 3-phosphoglycerate and the citrate/isocitrate isomeric pairs, respectively, are shown. These are the highest reported ion mobility resolving powers for molecules from the metabolome reported to date. The potential for DAEMS as a generalized screening tool is demonstrated with the separation of the substrates and products of two additional isomerases that present as potential therapeutic targets, chorismate mutase and triosephosphate isomerase. The separations are achieved at speeds compatible with the sample introduction rates of AEMS providing sufficient data points to integrate the peaks for quantitation without the use of internal standards. DMS hyphenated with acoustic sample ejection MS provides a unique solution to high-throughput mass spectrometry applications where separation of isomers and other types of isobaric overlaps are required.

DOI: https://doi.org/10.1021/acs.analchem.4c05341
Forensic Toxicol. 2024 Dec 19.

Method for determination of cytisine in post-mortem biological matrices and its application to two forensic cases.

Karolina Nowak, Paweł Szpot, Marcin Zawadzki, Agnieszka Chłopaś-Konowałek.

   PURPOSE: Cytisine is the active ingredient in preparations used for smoking cessation. Its popularity is attributed to its low cost, efficacy, and low incidence of adverse effects. Additionally, its easy over-the-counter availability is also significant. This accessibility makes it a potential substance for use in suicidal attempts. The aim of this study was to develop a method for the determination of cytisine in biological material for use in clinical and forensic toxicology, and to apply this method in authentic cases.
METHODS: Biological samples were subjected to liquid-liquid extraction using cytisine-d4 as an internal standard. Analyses were performed using a Hydrophilic Interaction Liquid Chromatography (HILIC) column with the technique of ultra-high-performance liquid chromatography coupled with triple quadrupole tandem mass spectrometry.
RESULTS: For both matrices (blood and urine), the linear concentration range was 5-1000 ng/mL. The method met all validation requirements. The concentration of cytisine in a man taking it for smoking cessation in post-mortem materials was 21.4 ng/mL in blood, 958.9 ng/mL in urine, ca. 30 ng/mL in vitreous humor, and ca. 40 ng/mL in bile. In contrast, for a man with cytisine intoxication, the concentration was 174.6 ng/mL in blood and > 10,000 ng/mL in urine. In both cases, no N-methylcytisine was detected.
CONCLUSIONS: The developed method can be used for the determination of cytisine in post-mortem biological matrices as well as for clinical purpose. We presented the concentrations of cytisine in the post-mortem biological samples of a man taking cytisine for smoking cessation and of a man with suicidal cytisine poisoning.

Keywords:   N-Methylcytisine; Cytisine; HPLC–MS/MS; Intoxication; Post-mortem; Smoking cessation

DOI:  https://doi.org/10.1007/s11419-024-00710-3
Metabolomics. 2024 Dec 19. 21(1): 10

A-SIMA/A-MAP: a comprehensive toolkit for NMR-based metabolomics analysis.

Abigail Chiu, Mehdi Rahimi, Woonghee Lee.

   INTRODUCTION: Metabolomics is the comprehensive study of small molecules in biological systems. It has recently garnered attention for its wide variety of applications such as diseases, drug treatments, agriculture, and more. As the interest in metabolomics grow, meeting the demands of cutting-edge research requires software tools that not only advance analytical capabilities, but also prioritize user-friendly features.
OBJECTIVES: In response to this need, we present two new computer programs, A-SIMA: Advanced-Software for Interactive Metabolite Analysis and A-MAP: A Multivariate Analysis Program. These tools aim to introduce new capabilities for metabolite identification and data analysis, and thereby advancing the computational methodology in NMR-based metabolomics.
METHODS: A-SIMA is designed with an easy-to-use graphical user interface which allows users to perform metabolite identification on 1D and 2D NMR data effortlessly with complete control over the identification process. Similarly, A-MAP facilitates multivariate statistical analysis of metabolite data through a straightforward process. It offers analysis options such as Principal Component Analysis and Orthogonal Partial Least Squares-Discriminant Analysis using regions of interests as inputs.
RESULTS: Both A-SIMA and A-MAP are pre-built in the POKY suite, available at https://poky.clas.ucdenver.edu , with tutorial videos on YouTube for guidance on not only the programs, but also installation. The POKY suite is a software program for NMR biomolecular analysis. With the addition of these programs in POKY, researchers and professionals can experience a fully integrated process for every step of their metabolite analysis. Data can also be easily exported from these programs to be applied elsewhere.
CONCLUSION: The introduction of A-SIMA and A-MAP can be promising tools that can lead significant advancements in metabolomics research. These tools offer enhanced capabilities for metabolite analysis and statistical modelling in a user-friendly manner. Their integration into the POKY suite ensures accessibility, usability, and efficiency.

Keywords:  A-MAP; A-SIMA; MetaLib; Metabolomics; NMR; POKY; Software

DOI:  https://doi.org/10.1007/s11306-024-02208-w
Rapid Commun Mass Spectrom. 2025 Mar 30. 39(6): e9973

Development of a Matrix-Assisted Laser Desorption Ionization High Resolution Mass Spectrometry Method for the Quantification of Camalexin and Scopoletin in Arabidopsis thaliana.

Leonardo Parasecolo, Ivan M Monsalvo, Nikola Kovinich, Demian R Ifa.

   RATIONALE: Understanding plant defense mechanisms against pathogens is essential for enhancing agricultural productivity and crop protection. This study focuses on the quantification of camalexin and scopoletin, two critical phytoalexins in Arabidopsis thaliana, using mass spectrometry techniques. Precise measurement of these compounds provides insights into plant resistance and supports agricultural research.
METHODS: Camalexin and scopoletin were quantified using matrix-assisted laser desorption ionization high-resolution mass spectrometry (MALDI-HRMS). The matrix and solvent conditions were optimized to maximize sensitivity and accuracy. MS/MS experiments confirmed compound identification with high mass accuracy (mass error < 5 ppm). The method was validated through comparative analysis of wild-type (WT) and mutant Arabidopsis lines, using internal standards and multiple replicates to ensure precision and reliability.
RESULTS: The method exhibited high linearity for scopoletin (R2 = 0.9992) and camalexin (R2 = 0.9987) across concentration ranges of 0.16-5 and 0.31-5 μM, respectively. Limits of detection (LOD) were 0.16 μM for camalexin and 0.04 μM for scopoletin, with limits of quantification (LOQ) at 0.2 μM and 0.08 μM, respectively. Samples analysis demonstrated reliable quantification in WT and mutant lines, with significant reductions in camalexin and scopoletin levels observed in the atwrky33-2 and atmyb15-1 mutants, respectively. Additionally, the method detected sub-physiological concentrations, confirming its sensitivity and robustness for low-level detection.
CONCLUSIONS: This study presents a validated, precise, and accurate MALDI-HRMS method for the quantification of camalexin and scopoletin in Arabidopsis thaliana. The approach not only enhances understanding of plant defense mechanisms but also offers potential applications for biotechnological and agricultural research, especially for investigating genetic variations and stress-induced phytoalexin production.

Keywords:  Mass spectrometry; Method development; Phytoalexin; plant biology

DOI:  https://doi.org/10.1002/rcm.9973
Phytochem Anal. 2024 Dec 19.

Isomer Differentiation by UHPLC-Q-Exactive-Orbitrap MS led to Enhanced Identification of Daphnane Diterpenoids in Daphne tangutica.

Kouharu Otsuki, Mi Zhang, Lingjian Tan, Masayoshi Komaki, Akane Shimada, Takashi Kikuchi, Di Zhou, Ning Li, Wei Li.

   INTRODUCTION: Liquid chromatography-mass spectrometry (LC-MS) has enhanced the rapid, accurate analysis of complex plant extracts, eliminating the need for extensive isolation. Tandem mass spectrometry (MS/MS) further enhances this process by providing detailed structural information. However, differentiating structural isomers remains a challenge due to their minor spectral and structural differences.
OBJECTIVE: This study aimed to extend the applicability of LC-MS/MS for the structural identification of daphnane diterpenoids, with a particular focus on distinguishing functional isomers.
METHODS: LC-MS analyses were performed using an UHPLC-Q-Exactive-Orbitrap MS. The MS conditions for distinguishing isomers were optimized using in-source CID and HCD modes with reference compounds. A qualitative analysis was then conducted on the extract of Daphne tangutica. The chemical structures of the detected daphnane diterpenoids were estimated by analyzing the fragmentation patterns in both the mass spectra and product ion spectra. These identifications were further validated by isolation and comparison with an in-house daphnane diterpenoid library.
RESULTS: By optimizing MS conditions, especially in the negative ion mode, it was possible to accurately distinguish structural isomers such as yuanhuajine and gniditrin. Qualitative analysis of D. tangutica identified a total of 28 daphnanes, including seven previously unreported compounds. Furthermore, a novel geometric isomer of gniditrin was isolated by conducting isolation on the crude diterpenoid fraction.
CONCLUSION: This study demonstrated that LC-MS/MS analysis can effectively distinguish functional isomers of daphnane diterpenoids, thereby enhancing the identification of daphnanes in plant extracts and highlighting its potential as a powerful tool for phytochemical analysis.

Keywords:   Daphne tangutica ; Daphnane; LC–MS; Thymelaeaceae; isomer differentiation

DOI:  https://doi.org/10.1002/pca.3491
J Chromatogr B Analyt Technol Biomed Life Sci. 2024 Dec 12. pii: S1570-0232(24)00432-X. [Epub ahead of print]1251 124423

Development and validation of a quantification method for direct oral anticoagulants from capillary blood using volumetric absorptive microsampling and online SPE-LC-MS.

Patrick Opitz, Isabel Waltering, Georg Hempel.

The number of prescriptions for new direct oral anticoagulants (DOACs) apixaban, edoxaban, rivaroxaban and dabigatran has increased exponentially in recent years, increasingly replacing the old gold standard, vitamin-K-antagonists. Due to their wide therapeutic range, therapeutic drug monitoring (TDM) is not required, although it has been proven that this could significantly reduce side effects. In order to develop a cost-efficient and simple method for the simultaneous detection of the DOACs and phenprocoumon, a new technology for sample preparation from capillary blood in the ambulant sector named VAMS® was integrated and an LC-MS detector with on-line solid phase extraction (SPE) applying a Turboflow HTLC CycloneTM 1.0x50 mm column was used. The mobile phase consisted of methanol with water (3/97 v/v) and 0.1 % ammonia solution with a flow rate of 2.5 mL/min. For the chromatographic separation, a Phenomenex LTD Kinetex 2.6 µm C18 100 Å, 100x3.0 mm column with a flow rate of 0.3 mL/min in gradient mode was utilized. The mobile phase consisted of acetonitrile, water and formic acid (A: 10:90:0.1 v/v and B: 95:05:0.1 v/v). The method was fully validated in the therapeutic range of the substances according to current guidelines. The LLOQ ranged from 3.5 µg/L for rivaroxaban to 88 µg/L for phenprocoumon and the intra-day and inter-day precision was less than 13 % and 12 %, while the accuracy was within a range of 85.7-113 % and 88.7-106 %, respectively. Samples could be stored in the Mitra® devices for at least seven days at room temperature except of dabigatran. Because the Mitras® were used, exactly 10 µL of blood could be drawn and no significant haematocrit effect was observed. A reliable, simple and cost-effective extraction and analysis LC-MS method could be developed and validated. This method is therefore applicable in ambulatory care.

DOI: https://doi.org/10.1016/j.jchromb.2024.124423
Plants (Basel). 2024 Nov 22. pii: 3278. [Epub ahead of print]13(23):

Development of a Tandem Mass Spectral Library for the Detection of Triterpenoids in Plant Metabolome Based on Reference Standards.

Bibi Zareena, Syed Usama Y Jeelani, Adeeba Khadim, Arslan Ali, Jalal Uddin, Satyajit D Sarker, Matthias Rainer, Shaden A M Khalifa, Hesham R El-Seedi, Muhammad Ramzan, Syed Ghulam Musharraf.

  Plant triterpenoids represent a diverse group of secondary metabolites and are thought to be valuable for therapeutic applications. For drug development, lead optimization, better knowledge of biological pathways, and high-throughput detection of secondary metabolites in plant extracts are crucial. This paper describes a qualitative method for the rapid and accurate identification of various triterpenoids in plant extracts using the LC-HR-ESI-MS/MS tool in combination with the data-dependent acquisition (DD) approach. A total of 44 isolated, purified, and characterized triterpenoids were analyzed. HR-MS spectra and tandem mass spectra (MS/MS) of each compound were recorded in the positive ionization mode in two different sets of collisional energies, i.e., (25-62.5 eV), and fixed collisional energies (10, 20, 30, and 40 eV). As a result, three triterpenoids were identified in all plant extracts using the retention time, high-resolution mass spectra, and/or MS/MS spectra. The developed method will be helpful with other plant extracts/botanicals, as well as in the search for new triterpenoids in the kingdom Plantae.

Keywords:  ESI-QTOF-MS/MS method; electrospray ionization–mass spectrometry; generation of spectral library; triterpenoids

DOI:  https://doi.org/10.3390/plants13233278
J Clin Med. 2024 Nov 29. pii: 7276. [Epub ahead of print]13(23):

Perspectives of Quantitative GC-MS, LC-MS, and ICP-MS in the Clinical Medicine Science-The Role of Analytical Chemistry.

Dimitrios Tsikas.

  Mass spectrometry (MS) is the only instrumental analytical technology that utilizes unique properties of matter, that is, its mass (m) and electrical charge (z). In the magnetic and/or electric fields of mass spectrometers, electrically charged native or chemically modified (millions) endogenous and (thousands) exogenous substances, the analytes, are separated according to their characteristic mass-to-charge ratio (m/z) values. Mass spectrometers coupled to gas chromatographs (GC) or liquid chromatographs (LC), the so-called hyphenated techniques, i.e., GC-MS and LC-MS, respectively, enable reliable determination of the concentration of analytes in complex biological samples such as plasma, serum, and urine. A particular technology is represented by inductively coupled plasma-mass spectrometry (ICP-MS), which is mainly used for the analysis of metal ions. The highest analytical accuracy is reached by using mass spectrometers with high mass resolution (HR) or by tandem mass spectrometers, as it can be realized with quadrupole-type instruments, such as GC-MS/MS and LC-MS/MS, in combination with stable-isotope labeled analytes that serve as internal standards, like a standard weight in scales. GC-MS belongs to the oldest and most advanced instrumental analytical technology. From the very beginning, GC-MS found broad application in basic and applied research sciences. GC-MS has played important roles in discovering biochemical pathways, exploring underlying mechanisms of disease, and establishing new evidence-based pharmacological therapy. In this article, we make an inventory of the use of instrumental mass spectrometry in the life sciences and attempt to provide a perspective study on the future of analytical mass spectrometry in clinical science, mainly focusing on GC-MS and LC-MS. We used information freely available in the scientific database PubMed (retrieved in August-November 2024). Specific search terms such as GC-MS (103,000 articles), LC-MS (113,000 articles), and ICP-MS (14,000 articles) were used in the Title/Abstract in the "PubMed Advanced Search Builder" including filters such as search period (1970-2024). In total, around 103,000 articles on GC-MS, 113,000 articles on LC-MS (113,000), and 14,000 articles on ICP-MS were found. In the period 1995-2023, the yearly publication rate accounted for 3042 for GC-MS articles and 3908 for LC-MS articles (LC-MS/GC-MS ratio, 1.3:1). Our study reveals that GC-MS/MS, LC-MS/MS, and their high-resolution variants are indispensable instrumentations in clinical science including clinical pharmacology, internal and forensic medicine, and doping control. Long-tradition manufacturers of analytical instruments continue to provide increasingly customer-friendly GC-MS and LC-MS apparatus, enabling fulfillment of current requirements and needs in the life sciences. Quantitative GC-MS and GC-MS/MS methods are expected to be used worldwide hand in hand with LC-MS/MS, with ICP-MS closing the gap left for metal ions. The significance of analytical chemistry in clinical science in academia and industry is essential.

Keywords:  analytical chemistry; clinical medicine; gas chromatography; life sciences; liquid chromatography; mass spectrometry

DOI:  https://doi.org/10.3390/jcm13237276
Talanta. 2024 Dec 09. pii: S0039-9140(24)01740-5. [Epub ahead of print]285 127358

Multi-sample analytical workflow for the determination of isoprostanes in oral fluid: A new tool for non-invasive evaluation of oxidative stress.

Francesco Bartolini, Martina Croce, Francesco Della Valle, Camilla Montesano, Federico Fanti, Dario Compagnone, Manuel Sergi.

  Oxidative stress is a pathological condition that contributes to the onset of various diseases. In this way, studying oxidative stress could lead to significant discoveries in the field of therapeutic and preventive medicine. Lipid peroxidation is the most significant event in the oxidative stress process and the gold standard biomarkers for endogenous oxidative damage to lipids are isoprostanes (IsoPs). This project aims to develop a reliable analytical method for the liquid-liquid microextraction technique, parallel artificial liquid membrane extraction (PALME) and LC-MS/MS analysis. PALME allowed to obtain a significant enrichment factor and, at the same time, a good sample purification by removing compounds that cause signal suppression, thereby reducing matrix effect. The chromatographic and mass spectrometric conditions have been fine tuned to improve the sensitivity of the method and therefore obtaining very low LOD and LOQ values. The recovery values obtained for the analytes are slightly above 50 %, except for 6-keto Prostaglandin F1A (24 %). Matrix effects were ≤ -10 %, with LODs ranging between 1 and 5 pg mL-1. The developed method is characterized by high sensitivity and low consumption of organic solvents, according to the principles of Green Analytical Chemistry and enables the determination of basal levels of IsoPs in oral fluid by processing 96 samples simultaneously.

Keywords:  Isoprostanes; LC-MS/MS; Oral fluid; Oxidative stress; Parallel artificial liquid membrane extraction

DOI:  https://doi.org/10.1016/j.talanta.2024.127358
Shokuhin Eiseigaku Zasshi. 2024 ;65(5): 129-135

[Validation Study of LC-MS/MS for Paralytic Shellfish Toxins and Tetrodotoxin in Scallops].

Satoshi Numano, Ryuichi Watanabe, Mayu Ozawa, Hajime Uchida, Ryoji Matsushima, Toshiyuki Suzuki.

  Recently, an instrumental analysis using LC-MS/MS has been developed and validated for paralytic shellfish toxins (PSTs) and tetrodotoxin (TTX) in bivalve molluscs in Japanese domestic and overseas. The method for 11 PSTs and TTX in scallops was validated in accordance with a previous report and CODEX-STAN. The samples were prepared by adding the standard mixture of PSTs and TTX to scallop (Patinopecten yessoensis) homogenates, extracted with 1% acetic acid and then cleaned up using an ENVI-Carb (250 mg/3 mL) cartridge. A single analyst extracted and analyzed in two samples per day on five successive days. As result of the validation, 11 PSTs were found falling within all the guideline criteria (the trueness, repeatability, within laboratory reproducibility, LOD, LOQ) in the tests using matrix-matched calibration or solvent calibration.However, the trueness of TTX was low value in the test using solvent standard. It would be due to the matrix effects at the LC-MS/MS analysis. The slope of the calibration curve at the matrix-matched standards of mussel was about the same as the slope at the solvent standards. Therefore, it is necessary to choose the most appropriate matrix depending on shellfish.

Keywords:  LC-MS/MS; paralytic shellfish toxins; saxitoxin; scallop (Patinopecten yessoensis); tetrodotoxin; validation study

DOI:  https://doi.org/10.3358/shokueishi.65.129
Lab Med. 2024 Dec 19. pii: lmae098. [Epub ahead of print]

A simple HPLC method for the determination of plasma progesterone levels in the third trimester of human pregnancy.

Mevlut Albayrak, Yucel Kadioglu, Fatma Demirkaya-Miloglu, Bunyamin Borekci.

  Progesterone is a steroid hormone primarily associated with pregnancy. A simple, rapid, and reliable high-performance liquid chromatography (HPLC) method has been developed and validated for the quantification of progesterone in human plasma. The method consists of a simple liquid-liquid extraction of progesterone and internal standard (estriol) from human plasma using a mixture of hexane and diethyl ether. The chromatographic determination of progesterone was performed using an acetonitrile-water (70:30, v/v) mobile phase with a C18 reversed-phase column. The method achieved an extraction recovery of greater than 96.4% from spiked plasma samples. Intra- and inter-day precision were generally acceptable, with relative SD% less than ≤6.60% and accuracy (relative error %) better than 3.64%. The developed and validated method was used to successfully quantify progesterone levels in plasma samples collected from women during the third trimester of pregnancy. Furthermore, a statistical comparison was conducted between progesterone concentrations in plasma samples obtained from 2 groups of pregnant women: group 1 (n = 9) at 30-35 weeks and group 2 (n = 9) at 36-41 weeks. The developed and validated HPLC method described in this study enables the successful determination of progesterone in human plasma, offering advantages such as shorter analysis time, simplicity, cost-effectiveness, and potential routine use during pregnancy.

Keywords:  high-performance liquid chromatography; pharmacy; pregnancy; progesterone

DOI:  https://doi.org/10.1093/labmed/lmae098
J Pharm Biomed Anal. 2024 Dec 13. pii: S0731-7085(24)00677-0. [Epub ahead of print]255 116635

Post-column denaturation-assisted hydrophobic interaction chromatography-mass spectrometry for rapid and in-depth characterization of positional isomers in cysteine-based antibody-drug conjugates.

Zhengqi Zhang, Anita P Liu, Hongxia Wang, Hillary A Schuessler.

  Antibody-drug conjugates (ADCs) represent a significant advancement in targeted cancer therapy, offering the potential to selectively deliver cytotoxic drugs to tumor cells while minimizing systemic toxicity. However, the structural complexity of ADCs, particularly those conjugated through cysteine residues, poses significant analytical challenges. Due to the hydrophobicity of ADCs, Hydrophobic interaction chromatography (HIC) is often the method of choice to analyze the drug-to-antibody ratio (DAR). However, it requires high-concentration salts, which are often incompatible with mass spectrometry (MS) analysis. By employing ammonium acetate as an MS-compatible salt and integrating a 4-way liquid junction cross configuration for simultaneous introduction of the makeup flow and splitting the flow right before coupling to a mass spectrometer, we achieve high-quality separation and sensitive mass spectrometric analysis. This innovative setup allows for simultaneous DAR measurement and positional isomer characterization by switching the makeup flow solvent from water to a denaturation solution. Our method offers a streamlined and effective approach to ADC characterization, facilitating the identification of positional isomers without the need for fractionation or multiple chromatographic steps. The versatility and robustness of this HIC-MS method are demonstrated through the analysis of two ADCs, highlighting its potential for broad application in ADC development and quality control.

Keywords:  Antibody-drug conjugates; Critical quality attributes; Drug-antibody-ratio; Hydrophobic interaction chromatography; Mass spectrometry; Positional isomers

DOI:  https://doi.org/10.1016/j.jpba.2024.116635
Rapid Commun Mass Spectrom. 2025 Feb 28. 39(4): e9952

Establishment of a Mass Spectrometric Fingerprint of the Most Common Phytocannabinoids in Electrospray Ionization in Positive Ion Mode.

Radwa Mahmoud, Amir Khajavinia, Sedigheh Barzegar, Randy W Purves, Robert B Laprairie, Anas El-Aneed.

   BACKGROUND: Analysis of the phytocannabinoids holds significant importance because of their various pharmacological properties and potential therapeutic applications. Tandem mass spectrometry (MS/MS) coupled with electrospray ionization in positive ion mode is employed in this study to describe the collision-induced dissociation (CID) behavior of a series of common phytocannabinoids with the aim of establishing a generalized MS/MS fingerprint.
MATERIALS AND METHODS: Eight phytocannabinoids, namely, ∆9-tetrahydrocannabinol (THC), cannabidiol (CBD), cannabichromene (CBC), cannabigerol (CBG), tetrahydrocannabivarin (THCV), 11-hydroxy-Δ9-tetrahydrocannabinol (11-OH-THC), 6-hydroxy-cannabidiol (6-OH-CBD), and 7-hydroxy-cannabidiol (7-OH-CBD), were studied. A Quadrupole-Orbitrap mass spectrometer equipped with a heated electrospray ionization (HESI-Q Orbitrap) is used to provide accurate mass measurement data for single-stage and MS/MS analysis. In addition, a triple quadrupole-linear ion trap mass spectrometer was used to perform MS/MS and second-generation MS/MS (MS3) analyses.
RESULTS: An abundant, singly charged [M + H]+ species during single-stage MS analysis was observed for all phytocannabinoids, with mass accuracies less than 5 ppm. Because of their structural similarities, all compounds showed some common fragmentation behavior in their MS/MS analysis. By comparing the fragmentation patterns and identifying diagnostic ions, a universal MS/MS fragmentation pattern was established. The structures of the various product ions proposed in the fragmentation pathway were confirmed with exact mass measurements and MS3 experiments.
CONCLUSIONS: The evaluated compounds contain varying functional groups, resulting in unique product ions, specific to each structure. The MS/MS fingerprints will be utilized in the future for the identification of new structures as well as the development of targeted quantification methods.

Keywords:  MS/MS; MS/MS fingerprint; fragmentation pathways; phytocannabinoids

DOI:  https://doi.org/10.1002/rcm.9952
Anal Chem. 2024 Dec 18.

Transcending Resolution Limits in HPLC and Diffusion NMR.

Nouran A Hamed, Alexandria K Shread, Gareth A Morris, Mathias Nilsson.

Mixture analysis is crucial in many areas of chemistry, and a wide variety of separation methods are in use. A common method for physical separation is high-performance liquid chromatography (HPLC), but resolution is a problem: chemically similar species coelute. An alternative approach is diffusion-ordered NMR spectroscopy (DOSY), in which the signals of mixture components are separated according to the diffusion coefficient. Again, separation is limited if species diffuse similarly or have overlap in their NMR spectra. Using the two techniques in combination can resolve both NMR spectra and the elution profiles of individual components, even where both techniques fail when used in isolation. Recording diffusion NMR data as a function of HPLC retention time gives a three-dimensional (3D) data set that can be analyzed using multiway statistical methods. PARAFAC analysis of diffusion NMR data measured from HPLC eluate for commercial "monoacetin" (a mixture of glycerol and its mono-, di-, and triacetates) yielded fully resolved and quantitative NMR spectra and elution profiles for all four components, whereas neither HPLC nor diffusion NMR applied independently was able to resolve the components.

DOI: https://doi.org/10.1021/acs.analchem.4c04418