Journal articles: 'High resolution mass spectrometry (HRMS)'

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Bouza, Marcos, Bienvenida Gilbert-López, Juan Francisco García-Reyes, and Pilar Gema Rodríguez Ortega. "Measuring the mass of an electron: an undergraduate laboratory experiment with high resolution mass spectrometry." Chemistry Teacher International 4, no. 1 (October 21, 2021): 15–22. http://dx.doi.org/10.1515/cti-2021-0016.

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Abstract High-resolution mass spectrometry (HRMS) has become increasingly affordable and user-friendly. Its potential spans a wide range of applications and experiments including the measurement of accurate masses, supporting the elucidation of elemental compositions and the identification of unknown compounds. To illustrate the main features of mass spectrometry, and particularly, of HRMS, we have designed and implemented a 3-h laboratory experiment using direct infusion electrospray HRMS analysis of non-steroidal anti-inflammatory drugs (e.g., ibuprofen or naproxen) solutions, acquiring full-scan spectra in both positive and negative ionization modes. The experimental accurate mass measurements (m/z values) of selected characteristic fragment ions -so called twin ions, with common elemental composition in both ionization modes but with different charge, allow the indirect measurement of the mass of an electron with relative errors below 5% with respect to the accepted IUPAC value (0.00055 Da). The experiment demonstrates how powerful and useful HRMS can be for research challenges often encountered during undergraduate or graduate research projects as well as for addressing undergraduate level general chemistry problems that provide the opportunity to discuss aspects related to the Nature of Science in an analytical chemistry context (such as measurement precision and accuracy).

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Liu, Ju, Jing Li, Chris Tran, Krishna Aluri, Xuemei Zhang, Valerie Clausen, Ivan Zlatev, et al. "Oligonucleotide quantification and metabolite profiling by high-resolution and accurate mass spectrometry." Bioanalysis 11, no. 21 (November 2019): 1967–80. http://dx.doi.org/10.4155/bio-2019-0137.

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Aim: Advancements in RNA interference therapeutics have triggered development of improved bioanalytical methods for oligonucleotide metabolite profiling and high-throughput quantification in biological matrices. Results & methodology: HPLC coupled with high-resolution mass spectrometry (LC-HRMS) methods were developed to investigate the metabolism of a REVERSIR™ molecule in vivo. Plasma and tissue samples were extracted using solid-phase extraction followed by LC-HRMS analysis for metabolite profiling and quantification. The method was qualified from 10 to 5000 ng/ml (plasma) and 100 to 50000 ng/g (liver and kidney). In rat liver, intra and interday accuracy ranged from 80.9 to 118.5% and 88.4 to 111.9%, respectively, with acceptable precision (<20% CV). Conclusion: The LC-HRMS method can be applied for metabolite profiling and quantification of oligonucleotides in biological matrices.

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Sun, Yuchen, Shin-ichiro Nitta, Kosuke Saito, Ryuta Hosogai, Keiko Nakai, Ryoya Goda, Masaaki Kakehi, et al. "Development of a bioanalytical method for an antisense therapeutic using high-resolution mass spectrometry." Bioanalysis 12, no. 24 (December 2020): 1739–56. http://dx.doi.org/10.4155/bio-2020-0225.

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Background: Ion-pairing reverse-phase LC coupled with high-resolution mass spectrometry (IP-LC/HRMS) has gained attention in oligonucleotide therapeutic bioanalyses owing to its high sensitivity and selectivity. However, optimization and validation of IP-LC/HRMS-based methods are rare. The objective of this study is the development of a sensitive and reproducible IP-LC/HRMS-based bioanalytical method using clinically approved mipomersen as a model for antisense oligonucleotides. Materials & methods/results: Mipomersen was extracted from rat plasma using Clarity OTX SPE and quantified by IP-LC/HRMS. The calibration range was 0.5–250.0 ng/ml. The developed method met the general regulatory criteria for accuracy, precision, carry-over, selectivity, matrix effect and dilution integrity. Conclusion: A highly sensitive and reliable method for mipomersen measurement with potential antisense oligonucleotide bioanalysis applications has been developed.

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Turnipseed, Sherri B., Jack J. Lohne, and Joe O. Boison. "Review: Application of High Resolution Mass Spectrometry to Monitor Veterinary Drug Residues in Aquacultured Products." Journal of AOAC INTERNATIONAL 98, no. 3 (May 1, 2015): 550–58. http://dx.doi.org/10.5740/jaoacint.14-265.

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Abstract High resolution MS (HRMS) instruments provide accurate mass measurements. With HRMS, virtually an unlimited number of compounds can be analyzed simultaneously because full-scan data are collected, rather than preselected ion transitions corresponding to specific compounds. This enables the development of methods that can monitor for a wide scope of residues and contaminants in aquacultured fish and shellfish including antibiotics, metabolites, and emerging contaminants. Applications of HRMS to the analysis of veterinary drug residues in aquacultured products are summarized in this review including methods for screening, quantifying, and identifying drug residues in these matrixes. The use of targeted, semi-targeted, and nontargeted analysis of HRMS data and the implications to the global aquaculture industry are also reviewed.

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Qin Weihan and Yang Yong, Qin Weihan and Yang Yong. "Identification of New Compounds in Epimedium L. based on Flavonol Secondary Metabolism and High-Resolution Mass Spectrometry." Journal of the chemical society of pakistan 44, no. 1 (2022): 40. http://dx.doi.org/10.52568/000982/jcsp/44.01.2022.

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To derive and verify the chemical structure of the new components in Epimedium, the laws of secondary metabolism and high-resolution mass spectrometry (HRMS) were combined. Based on the chemical literature of Epimedium, the secondary metabolism network of flavonols was constructed, and the possible metabolites were deduced. After the metabolites, information was imported into PeakView software, and the ions with a mass error andlt; 5 ppm, correct isotope distribution, and containing secondary fragments were taken as the target compounds. The chemical structures of new compounds were identified and verified by combining Formula Finder, Mass Calculators, online databases (SciFinder, Reaxys, ChemSpider, etc.) and secondary fragmentation rules. In this study, a total of 4 metabolic pathways and 64 compound structures were deduced, and two new components and 12 new compounds were identified in 54 batches of Epimedium samples from 15 species by high-resolution mass spectrometry. Furthermore, the long and tedious steps of phytochemical separation were simplified, experimental costs were reduced, and a new idea and method were suggested for the analysis and identification of secondary metabolites with pharmacological activity.

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Kataev, S. S., O. N. Dvorskaya, M. A. Gofenberg, A. V. Labutin, and A. B. Melentyev. "ANALYTICAL FEATURES OF SYNTHETIC MDMB(N)-073F CANNABIMIMETICS AND ITS MARKERS IN BIOLOGICAL MATERIAL." Pharmacy & Pharmacology 7, no. 4 (September 10, 2019): 184–97. http://dx.doi.org/10.19163/2307-9266-2019-7-4-184-197.

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The aim of the research is to study both analytical features of synthetic MDMB(N)-073F cannabimimetics of indazole carboxamides group by gas chromatography methods combined with tandem mass spectrometry (GC-MS) and high performance liquid chromatography with high-resolution mass spectrometry (HPLC-HRMS) as well as characteristics of the major MDMB(N)-073F metabolite, its glucuronide and derivatives, using gas chromatography with mass-spectrometric (GC-MS) detection and high-performance liquid chromatography (HPLC) with MS/MS mass spectrometry (HPLC-MS/MS) in urine samples to be applied in expert practice, chemical-toxicological and forensic and chemical analyses.Materials and methods. To carry out the study, the following materials were used: plant-based objects with narcotic drugs withdrawn from illegal trafficking and applied to them;. urine samples to be studied under chemical-toxicological and forensic and chemical analyses. For solid-phase epitaxy, SampliQ EVIDEX TFE cartridges – 200 mg – 3 ml (Agilent, USA) were used for sample preparation; β-glucuronidase, Type HP-2, From Helix Pomatia, 100000 UA/ml (Sigma-ALDRICH CHEMI, Germany) was used for enzymatic hydrolysis. GC-MS/MS analysis was made using Agilent 7890 gas chromatograph with a tandem quadrupolar mass-spectrometer Agilent 7000 (Agilent, США); GC-MS analysis was carrid out using gas chromatograph Agilent 7820 with mass-selective detector Agilent 5975 (Agilent, USA); HPLC-HRMS research was made on liquid chromatograph Agilent 1260 with tandem hybrid high-resolution quadrupole-time-of-flight detector Agilent 6540 (Agilent, США); liquid chromatograph Agilent 1260 with Agilent 6460 (Agilent, USA) with tandem mass-spectrometer were used for making HPLC-MS/MS research.Results. The structure of MDMB(N)-073F compound has been confirmed and an exact mass of the protonated molecule corresponding to the chemical formula C19H27FN3O3 fixed by GC-MS/MS and HPLC-HRMS methods. Spectral characteristics of MDMB(N)-073F have been given. One of the branches in MDMB(N)-073F biotransformation in the human body found out by GC-MS and HPLC-MS/MS methods, is the ester decomposition with further conjugation of the resulting acid. The product interacting with glucuronic acid, is found to be the conjugate of major MDMB(N)-073F metabolite of the Ist phase in biotransformation. Metabolites appearing due to the ester decomposition and its conjugate with glucuronic acid, are recommended to be used as markers for synthetic MDMB(N)-073F cannabimimetics in the analysis by chromatographic methods; they can be used for regular screening of biological samples.Conclusion. The research results presented here, are the following: the analytical features characteristic for synthetic MDMB(N)-073F cannabimimetics found out by gas chromatography methods combined with tandem mass spectrometry (GC-MS/ MS) and liquid chromatography of hybrid high-resolution quadrupole-time-of-flight mass spectrometry (HPLC-HRMS), as well as characteristics of major MDMB(N)-073F metabolite, its glucuronide and derivatives with the use of gas chromatography with mass-spectrometric detection (GC-MS) and liquid chromatography combined with tandem mass spectrometry (HPLC-MS/MS) in urine samples to be applied in expert practice, chemical-toxicological, forensic and chemical analyses.

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Klingberg, Joshua, Bethany Keen, Adam Cawley, Daniel Pasin, and Shanlin Fu. "Developments in high-resolution mass spectrometric analyses of new psychoactive substances." Archives of Toxicology 96, no. 4 (February 9, 2022): 949–67. http://dx.doi.org/10.1007/s00204-022-03224-2.

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AbstractThe proliferation of new psychoactive substances (NPS) has necessitated the development and improvement of current practices for the detection and identification of known NPS and newly emerging derivatives. High-resolution mass spectrometry (HRMS) is quickly becoming the industry standard for these analyses due to its ability to be operated in data-independent acquisition (DIA) modes, allowing for the collection of large amounts of data and enabling retrospective data interrogation as new information becomes available. The increasing popularity of HRMS has also prompted the exploration of new ways to screen for NPS, including broad-spectrum wastewater analysis to identify usage trends in the community and metabolomic-based approaches to examine the effects of drugs of abuse on endogenous compounds. In this paper, the novel applications of HRMS techniques to the analysis of NPS is reviewed. In particular, the development of innovative data analysis and interpretation approaches is discussed, including the application of machine learning and molecular networking to toxicological analyses.

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Lu, Peng, Mei-Juan Fan, Qian Zhang, Qing-Xia Zheng, Ping-Ping Liu, Bing Wang, Jun-Wei Guo, et al. "A novel strategy for extracted ion chromatogram extraction to improve peak detection in UPLC-HRMS." Analytical Methods 10, no. 42 (2018): 5118–26. http://dx.doi.org/10.1039/c8ay01850b.

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Luo, Y. R., C. Yun, K. L. Lynch, and K. Comstock. "A High-Resolution Liquid Chromatography-Mass Spectrometry Method for Identification of Toxic Natural Products in Clinical Cases." American Journal of Clinical Pathology 154, Supplement_1 (October 2020): S128. http://dx.doi.org/10.1093/ajcp/aqaa161.280.

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Abstract Introduction/Objective Many natural products have biological effects on humans and animals. Poisoning caused by natural products is often found in clinical toxicology cases. Liquid chromatography-high-resolution-mass spectrometry (LC-HRMS) has recently emerged as a powerful analytical tool for large-scale target screening, and the application of LC-HRMS can be expanded to solve the clinical cases of natural product poisoning. Methods The LC-HRMS method is based on a spectral library of 121 natural products. The spectral library was constructed by analyzing standards either in a Q-TOF mass spectrometer (only MS2 spectra acquired) or in an Orbitrap Tribrid mass spectrometer (MS2 and MS3 spectra acquired). Results The LC-HRMS method was verified for the limit of detection (LOD) and matrix effects in both serum and urine matrices. For each compound, the LOD was evaluated from 1.0 ng/ml to 1000 ng/ml for urine samples and from 0.50 ng/ml to 500 ng/ml for serum samples. The matrix effects were determined at three concentration levels andranged from 30.4% to 123.5% for urine samples and from 23.4% to 132.9% for serum samples. The LC-HRMS method was successfully applied to identify the culprits in three clinical cases. In addition, the combined use of MS2 and MS3 spectra enhanced the accuracy of compound identification, in library search reducing the importance of retention time that varies among instruments and consumable lots. In Case 1, the patient presented with paresthesias, arrhythmias, and stiffened arms and legs. The toxic alkaloid aconitine was identified in the serum sample and the extract of herbs that the patient ingested. In Case 2, the patients presented with weakness, dizziness, and vomiting. The symptoms were caused by mistakenly taking Nicotiana glauca leaves and the alkaloid anabasine was identified as the culprit. In Case 3, the patients were suspected of intoxicated by taking too much extract of lupini beans. The culprit alkaloids from lupini beans lupanine and sparteine were found in the serum samples. Conclusion The involvement of a toxicology laboratory with the capability to perform the LC-HRMS method and with experience in the investigation of undifferentiated cases provides a unique diagnostic advantage in cases where exposure to toxic substances is possible.

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Morabito, Aurelia, Giulia De Simone, Manuela Ferrario, Francesca Falcetta, Roberta Pastorelli, and Laura Brunelli. "EASY-FIA: A Readably Usable Standalone Tool for High-Resolution Mass Spectrometry Metabolomics Data Pre-Processing." Metabolites 13, no. 1 (December 21, 2022): 13. http://dx.doi.org/10.3390/metabo13010013.

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Flow injection analysis coupled with high-resolution mass spectrometry (FIA-HRMS) is a fair trade-off between resolution and speed. However, free software available for data pre-processing is few, web-based, and often requires advanced user specialization. These tools rarely embedded blank and noise evaluation strategies, and direct feature annotation. We developed EASY-FIA, a free standalone application that can be employed for FIA-HRMS metabolomic data pre-processing by users with no bioinformatics/programming skills. We validated the tool's performance and applicability in two clinical metabolomics case studies. The main functions of our application are blank subtraction, alignment of the metabolites, and direct feature annotation by means of the Human Metabolome Database (HMDB) using a minimum number of mass spectrometry parameters. In a scenario where FIA-HRMS is increasingly recognized as a reliable strategy for fast metabolomics analysis, EASY-FIA could become a standardized and feasible tool easily usable by all scientists dealing with MS-based metabolomics. EASY-FIA was implemented in MATLAB with the App Designer tool and it is freely available for download.

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Xiu, Yang, Huanxi Zhao, Yue Gao, Wenlong Liu, and Shuying Liu. "Chemical transformation of ginsenoside Re by a heteropoly acid investigated using HPLC-MSn/HRMS." New Journal of Chemistry 40, no. 11 (2016): 9073–80. http://dx.doi.org/10.1039/c6nj01702a.

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Kokotou, Maroula G. "Study of the Fragmentation Pathways of Sulfonamides by High-resolution Mass Spectrometry: Application to their Detection in Plasma by Direct Infusion." Current Pharmaceutical Analysis 16, no. 5 (June 15, 2020): 513–19. http://dx.doi.org/10.2174/1573412915666181205115350.

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Background: The high resolving and accuracy power of the HRMS instrument enabled us to identify the product ions and to propose detailed fragmentation pathways and diagnostic fragment ions. Methods: In the present work, the fragmentation pathways of five sulfonamides antibiotics, namely sulfamerazine, sulfathiazole, sulfadiazine, sulfadimethoxine and sulfamethoxazole, by High-Resolution Mass Spectrometry (HRMS) are presented. The HRMS spectra were recorded with a Q-TOF (Time of Flight) spectrometer with Electrospray Ionization (ESI) in both negative and positive mode. Results: Specific characteristic ions for each one of the sulfonamide antibiotics under positive ESI mode are proposed for the first time. Fragment ions of this particular class of analytes may be used to rapidly identify compounds with common structural features. Conclusion: The direct infusion of plasma samples, avoiding any prior chromatographic steps, to identify the existence of sulfonamide antibiotics is demonstrated herein.

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Sah, Samyukta, Sylvia R. Yun, David A. Gaul, Andro Botros, Eun Young Park, Olga Kim, Jaeyeon Kim, and Facundo M. Fernández. "Targeted Microchip Capillary Electrophoresis-Orbitrap Mass Spectrometry Metabolomics to Monitor Ovarian Cancer Progression." Metabolites 12, no. 6 (June 9, 2022): 532. http://dx.doi.org/10.3390/metabo12060532.

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The lack of effective screening strategies for high-grade serous carcinoma (HGSC), a subtype of ovarian cancer (OC) responsible for 70–80% of OC related deaths, emphasizes the need for new diagnostic markers and a better understanding of disease pathogenesis. Capillary electrophoresis (CE) coupled with high-resolution mass spectrometry (HRMS) offers high selectivity and sensitivity for ionic compounds, thereby enhancing biomarker discovery. Recent advances in CE-MS include small, chip-based CE systems coupled with nanoelectrospray ionization (nanoESI) to provide rapid, high-resolution analysis of biological specimens. Here, we describe the development of a targeted microchip (µ) CE-HRMS method, with an acquisition time of only 3 min and sample injection volume of 4nL, to analyze 40 target metabolites in serum samples from a triple-mutant (TKO) mouse model of HGSC. Extracted ion electropherograms showed sharp, baseline resolved peak shapes, even for structural isomers such as leucine and isoleucine. All calibration curves of the analytes maintained good linearity with an average R2 of 0.994, while detection limits were in the nM range. Thirty metabolites were detected in mouse serum with recoveries ranging from 78 to 120%, indicating minimal ionization suppression and good accuracy. We applied the µCE-HRMS method to biweekly-collected serum samples from TKO and TKO control mice. A time-resolved analysis revealed characteristic temporal trends for amino acids, nucleosides, and amino acid derivatives. These metabolic alterations are indicative of altered nucleotide biosynthesis and amino acid metabolism in HGSC development and progression. A comparison of the µCE-HRMS dataset with non-targeted ultra-high performance liquid chromatography (UHPLC)–MS results showed identical temporal trends for the five metabolites detected with both platforms, indicating the µCE-HRMS method performed satisfactorily in terms of capturing metabolic reprogramming due to HGSC progression while reducing the total data collection time three-fold.

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Guyader, Meaghan E., Les D. Warren, Emily Green, Craig Butt, Gordana Ivosev, Richard L. Kiesling, Heiko L. Schoenfuss, and Christopher P. Higgins. "Prioritizing potential endocrine active high resolution mass spectrometry (HRMS) features in Minnesota lakewater." Science of The Total Environment 670 (June 2019): 814–25. http://dx.doi.org/10.1016/j.scitotenv.2019.02.448.

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Lefebvre, Donatien, Kevin Blanco-Valle, Jacques-Antoine Hennekinne, Stéphanie Simon, François Fenaille, François Becher, and Yacine Nia. "Multiplex Detection of 24 Staphylococcal Enterotoxins in Culture Supernatant Using Liquid Chromatography Coupled to High-Resolution Mass Spectrometry." Toxins 14, no. 4 (March 31, 2022): 249. http://dx.doi.org/10.3390/toxins14040249.

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Staphylococcal food poisoning outbreaks are caused by the ingestion of food contaminated with staphylococcal enterotoxins (SEs). Among the 27 SEs described in the literature to date, only a few can be detected using immuno-enzymatic-based methods that are strongly dependent on the availability of antibodies. Liquid chromatography, coupled to high-resolution mass spectrometry (LC-HRMS), has, therefore, been put forward as a relevant complementary method, but only for the detection of a limited number of enterotoxins. In this work, LC-HRMS was developed for the detection and quantification of 24 SEs. A database of 93 specific signature peptides and LC-HRMS parameters was optimized using sequences from 24 SEs, including their 162 variants. A label-free quantification protocol was established to overcome the absence of calibration standards. The LC-HRMS method showed high performance in terms of specificity, sensitivity, and accuracy when applied to 49 enterotoxin-producing strains. SE concentrations measured depended on both SE type and the coagulase-positive staphylococci (CPS) strain. This study indicates that LC-MS is a relevant alternative and complementary tool to ELISA methods. The advantages of LC-MS clearly lie in both the multiplex analysis of a large number of SEs, and the automated analysis of a high number of samples.

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Chindarkar, Nandkishor S., Michael R. Wakefield, Judith A. Stone, and Robert L. Fitzgerald. "Liquid Chromatography High-Resolution TOF Analysis: Investigation of MSE for Broad-Spectrum Drug Screening." Clinical Chemistry 60, no. 8 (August 1, 2014): 1115–25. http://dx.doi.org/10.1373/clinchem.2014.222976.

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Abstract BACKGROUND High-resolution mass spectrometry (HRMS) has the potential to supplement other drug screening platforms used in toxicology laboratories. HRMS offers high analytical specificity, which can be further enhanced by incorporating a fragment ion for each analyte. The ability to obtain precursor ions and fragment ions using elevated collision energies (MSE) can help improve the specificity of HRMS methods. METHODS We developed a broad-spectrum screening method on an ultraperformance liquid chromatography TOF mass spectrometer (UPLC-TOF-MS) using the MSE mode. A diverse set of patient samples were subjected to a simple dilute, hydrolyze, and shoot protocol and analyzed in a blind manner. Data were processed with 3 sets of criteria with increasing stringency, and the results were compared with the reference laboratory results. RESULTS A combination of retention time match (±0.2 min), a protonated analyte, and fragment ion mass accuracy of ±5 ppm produced zero false-positive results. Using these criteria, we confirmed 92% (253/275) of true positives. The positive confirmation rate increased to 98% (270/275) when the requirement for a fragment ion was dropped, but also produced 53 false positives. A total of 136 additional positive drug findings not identified by the reference methods were identified with the UPLC-TOF-MS. CONCLUSIONS MSE provides a unique way to incorporate fragment ion information without the need of precursor ion selection. A primary limitation of requiring a fragment ion for positive identification was that certain drug classes required high-energy collisions, which formed many fragment ions of low abundance that were not readily detected.

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Cao, Shanshan, Min Hu, Lingli Yang, Meiqin Li, Zhen Shi, Wenming Cheng, Yazhong Zhang, Fei Chen, Sheng Wang, and Qunlin Zhang. "Chemical Constituent Analysis of Ranunculus Sceleratus L. Using Ultra-High-Performance Liquid Chromatography Coupled with Quadrupole-Orbitrap High-Resolution Mass Spectrometry." Molecules 27, no. 10 (May 20, 2022): 3299. http://dx.doi.org/10.3390/molecules27103299.

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Ranunculus sceleratus L.(RS) has shown various pharmacological effects in traditional Chinese medicine. In our previous study, the positive therapeutic effect on α-naphthylisothiocyanate induced intrahepatic cholestasis in rats was obtained using TianJiu treatment with fresh RS. However, the chemical profile of RS has not been clearly clarified, which impedes the research progress on the therapeutic effect of RS. Herein, an ultra-high performance liquid chromatography coupled with quadrupole Orbitrap high-resolution mass spectrometry (UHPLC-Q-Orbitrap HRMS) method was developed to rapidly separate and identify multiple constituents in the 80% methanol extract of RS. A total of sixty-nine compounds (19 flavonoids, 22 organic acids, 6 coumarins, 4 lignans, 14 nitrogenous compounds, and 4 anthraquinones) were successfully characterized. A total of 12 of these compounds were unambiguously identified by standard samples. Their mass spectrometric fragmentation pathways were investigated. It is worth noting that flavonoids and lignans were identified for the first time in RS. In this study, we successfully provide the first comprehensive report on identifying major chemical constituents in RS by UHPLC-Q-Orbitrap HRMS. The obtained results enrich the RS chemical profile, paving the way for further phytochemical study, quality control, and pharmacological investigation of RS.

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Revelou, Panagiota-Kyriaki, Maroula G. Kokotou, and Violetta Constantinou-Kokotou. "Identification of Auxin Metabolites in Brassicaceae by Ultra-Performance Liquid Chromatography Coupled with High-Resolution Mass Spectrometry." Molecules 24, no. 14 (July 18, 2019): 2615. http://dx.doi.org/10.3390/molecules24142615.

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Auxins are signaling molecules involved in multiple stages of plant growth and development. The levels of the most important auxin, indole-3-acetic acid (IAA), are regulated by the formation of amide and ester conjugates with amino acids and sugars. In this work, IAA and IAA amide conjugates with amino acids bearing a free carboxylic group or a methyl ester group, along with some selected IAA metabolites, were studied in positive and negative electrospray ionization (ESI) modes, utilizing high-resolution mass spectrometry (HRMS) as a tool for their structural analysis. HRMS/MS spectra revealed the fragmentation patterns that enable us to identify IAA metabolites in plant extracts from eight vegetables of the Brassicaceae family using a fast and reliable ultra-performance liquid chromatography quadrupole time-of-flight mass spectrometry (UPLC-QToF-MS) method. The accurate m/z (mass to charge) ratio and abundance of the molecular and fragment ions of the studied compounds in plant extracts matched those obtained from commercially available or synthesized compounds and confirmed the presence of IAA metabolites.

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García-Gómez, Diego, Thomas Gaisl, Lukas Bregy, Pablo Martínez-Lozano Sinues, Malcolm Kohler, and Renato Zenobi. "Secondary electrospray ionization coupled to high-resolution mass spectrometry reveals tryptophan pathway metabolites in exhaled human breath." Chemical Communications 52, no. 55 (2016): 8526–28. http://dx.doi.org/10.1039/c6cc03070j.

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Kokotou, Maroula G., Christiana Mantzourani, Rodalia Babaiti, and George Kokotos. "Study of the Royal Jelly Free Fatty Acids by Liquid Chromatography-High Resolution Mass Spectrometry (LC-HRMS)." Metabolites 10, no. 1 (January 16, 2020): 40. http://dx.doi.org/10.3390/metabo10010040.

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The lipidome of royal jelly (RJ) consists of medium-chained (8–12 carbon atoms) free fatty acids. We present herein a liquid chromatography-high resolution mass spectrometry (HRMS) method that permits the determination of RJ fatty acids and at the same time the detection of suspect fatty acids. The method allows for the direct quantification of seven free fatty acids of RJ, avoiding any derivatization step. It was validated and applied in seven RJ samples, where the major RJ fatty acid trans-10-hydroxy-2-decenoic acid (10-HDA) was found to vary from 0.771 ± 0.08 to 0.928 ± 0.04 g/100 g fresh RJ. Four additional suspect fatty acids were simultaneously detected taking advantage of the HRMS detection.

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Wei, Cong, Louis S. Chupak, Thomas Philip, Benjamin M. Johnson, Robert Gentles, and Dieter M. Drexler. "Screening and Characterization of Reactive Compounds with In Vitro Peptide-Trapping and Liquid Chromatography/High-Resolution Accurate Mass Spectrometry." Journal of Biomolecular Screening 19, no. 2 (June 24, 2013): 297–307. http://dx.doi.org/10.1177/1087057113492852.

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The present study describes a novel methodology for the detection of reactive compounds using in vitro peptide-trapping and liquid chromatography–high-resolution accurate mass spectrometry (LC-HRMS). Compounds that contain electrophilic groups can covalently bind to nucleophilic moieties in proteins and form adducts. Such adducts are thought to be associated with drug-mediated toxicity and therefore represent potential liabilities in drug discovery programs. In addition, reactive compounds identified in biological screening can be associated with data that can be misinterpreted if the reactive nature of the compound is not appreciated. In this work, to facilitate the triage of hits from high-throughput screening (HTS), a novel assay was developed to monitor the formation of covalent peptide adducts by compounds suspected to be chemically reactive. The assay consists of in vitro incubations of test compounds (under conditions of physiological pH) with synthetically prepared peptides presenting a variety of nucleophilic moieties such as cysteine, lysine, histidine, arginine, serine, and tyrosine. Reaction mixtures were analyzed using full-scan LC-HRMS, the data were interrogated using postacquisition data mining, and modified amino acids were identified by subsequent LC-HRMS/mass spectrometry. The study demonstrated that in vitro nucleophilic peptide trapping followed by LC-HRMS analysis is a useful approach for screening of intrinsically reactive compounds identified from HTS exercises, which are then removed from follow-up processes, thus obviating the generation of data from biochemical activity assays.

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Alygizakis, Nikiforos, Vasileios Konstantakos, Grigoris Bouziotopoulos, Evangelos Kormentzas, Jaroslav Slobodnik, and Nikolaos S. Thomaidis. "A Multi-Label Classifier for Predicting the Most Appropriate Instrumental Method for the Analysis of Contaminants of Emerging Concern." Metabolites 12, no. 3 (February 23, 2022): 199. http://dx.doi.org/10.3390/metabo12030199.

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Liquid chromatography-high resolution mass spectrometry (LC-HRMS) and gas chromatography-high resolution mass spectrometry (GC-HRMS) have revolutionized analytical chemistry among many other disciplines. These advanced instrumentations allow to theoretically capture the whole chemical universe that is contained in samples, giving unimaginable opportunities to the scientific community. Laboratories equipped with these instruments produce a lot of data daily that can be digitally archived. Digital storage of data opens up the opportunity for retrospective suspect screening investigations for the occurrence of chemicals in the stored chromatograms. The first step of this approach involves the prediction of which data is more appropriate to be searched. In this study, we built an optimized multi-label classifier for predicting the most appropriate instrumental method (LC-HRMS or GC-HRMS or both) for the analysis of chemicals in digital specimens. The approach involved the generation of a baseline model based on the knowledge that an expert would use and the generation of an optimized machine learning model. A multi-step feature selection approach, a model selection strategy, and optimization of the classifier’s hyperparameters led to a model with accuracy that outperformed the baseline implementation. The models were used to predict the most appropriate instrumental technique for new substances. The scripts are available at GitHub and the dataset at Zenodo.

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Scendoni, Roberto, Emanuele Bury, Erika Buratti, Rino Froldi, Marta Cippitelli, Gianmario Mietti, and Mariano Cingolani. "Detection of Morphine and Opioids in Fingernails: Immunohistochemical Analysis and Confirmation with Ultra-High-Performance Liquid Chromatography Coupled with High-Resolution Mass Spectrometry." Toxics 10, no. 8 (July 26, 2022): 420. http://dx.doi.org/10.3390/toxics10080420.

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This study aimed to investigate the detection of morphine in fingernails from forensic autopsies using immunohistochemistry (IHC), with confirmation by ultra-high-performance liquid chromatography coupled with high-resolution mass spectrometry (UHPLC-HRMS). A primary antibody specific to morphine and a secondary antibody conjugated to horseradish peroxidase (HRP) was used. IHC on specimens of Subjects A and B (both drug addicts) resulted in the detection of morphine on a cell layer of the nail plate matrix. UHPLC-HRMS and GC-MS analysis showed that Subject A had a morphine concentration of 0.35 ng/mg in the fingernail and 472 ng/mL in the blood, while Subject B reached 1.23 ng/mg in the fingernail and 360 ng/ml in the blood. Most of those matrices were positive for codeine, methadone, EDDP, and 6-MAM. The use of IHC in Subject C (a former addict) showed no positivity for morphine in the fingernail, while the UHPLC-HRMS analysis confirmed its absence in the fingernail and blood. Additionally, an analysis of the scalp or pubic hair of the subjects was carried out using UHPLC-HRMS. The results suggest that IHC can be used to establish the site of accumulation of morphine in the nail matrix; for postmortem diagnosis; and that basic substances can be detected by UHPLC-HRMS. There are no previous studies on the use of IHC as a technique for forensic purposes in unconventional matrices, such as nails.

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Kritmetapak, Kittrawee, Louis A. Losbanos, Jolaine M. Hines, Katherine L. O’Grady, Candice Z. Ulmer, Hubert W. Vesper, Felicity T. Enders, Ravinder J. Singh, and Rajiv Kumar. "Chemical Characterization and Quantification of Circulating Intact PTH and PTH Fragments by High-Resolution Mass Spectrometry in Chronic Renal Failure." Clinical Chemistry 67, no. 6 (March 6, 2021): 843–53. http://dx.doi.org/10.1093/clinchem/hvab013.

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Abstract Background The precise concentrations of full-length parathyroid hormone (PTH1-84) and the identity and concentrations of PTH fragments in patients with various stages of chronic renal failure are unknown. Methods We developed a liquid chromatography-high resolution mass spectrometry (LC-HRMS) method to characterize and quantify PTH1-84 and PTH fragments in serum of 221 patients with progressive renal dysfunction. Following capture by matrix-bound amino-terminal or carboxyl-terminal region-specific antibodies and elution from matrix, PTH1-84 and PTH fragments were identified and quantitated using LC-HRMS. PTH was simultaneously measured using an intact PTH (iPTH) immunoassay. Results Full-length PTH1-84 and 8 PTH fragments (PTH28-84, 34-77, 34-84, 37-77, 37-84, 38-77, 38-84, and 45-84) were unequivocally identified and were shown to increase significantly when an eGFR declined to ≤17-23 mL/min/1.73m2. Serum concentrations of PTH1-84 were similar when measured by LC-HRMS following capture by amino-terminal or carboxyl-terminal immunocapture methods. In patients with an eGFR of <30 mL/min/1.73 m2, serum PTH concentrations measured using LC-HRMS were significantly lower than PTH measured using an iPTH immunoassay. PTH7-84 and oxidized forms of PTH1-84 were below the limit of detection (30 and 50 pg/mL, respectively). Conclusions LC-HRMS identifies circulating PTH1-84, carboxyl-terminal PTH fragments, and mid-region PTH fragments, in patients with progressive renal failure. Serum PTH1-84 and its fragments markedly rise when an eGFR decreases to ≤17-23 mL/min/1.73 m2. PTH concentrations measured using LC-HRMS tend to be lower than those measured using an iPTH immunoassay, particularly in severe chronic renal failure. Our data do not support the existence of circulating PTH7-84 and oxidized PTH1-84.

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Sharma, Nupur, Sadam H. Bhat, Gaurav Tripathi, Manisha Yadav, Babu Mathew, Vasundhra Bindal, Shvetank Sharma, Ekta Gupta, Jaswinder Singh Maras, and Shiv Kumar Sarin. "Global metabolome profiling of COVID-19 respiratory specimen using high-resolution mass spectrometry (HRMS)." STAR Protocols 3, no. 1 (March 2022): 101051. http://dx.doi.org/10.1016/j.xpro.2021.101051.

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Stock, Naomi L. "Introducing Graduate Students to High-Resolution Mass Spectrometry (HRMS) Using a Hands-On Approach." Journal of Chemical Education 94, no. 12 (November 2017): 1978–82. http://dx.doi.org/10.1021/acs.jchemed.7b00569.

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Filigenzi, Michael S., Emily E. Graves, Lisa A. Tell, Karen A. Jelks, and Robert H. Poppenga. "Quantitation of neonicotinoid insecticides, plus qualitative screening for other xenobiotics, in small-mass avian tissue samples using UHPLC high-resolution mass spectrometry." Journal of Veterinary Diagnostic Investigation 31, no. 3 (March 11, 2019): 399–407. http://dx.doi.org/10.1177/1040638719834329.

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We developed and validated a liquid chromatography–high-resolution mass spectrometry (LC-HRMS) analytical method for quantitatively measuring pesticide concentrations in small-body avian tissue samples using homogenized 1–2-d-old chicken carcasses as the test matrix. We quantified the following key insecticides: sulfoxaflor (sulfoximine class) and the neonicotinoids dinotefuran, nitenpyram, thiamethoxam, acetamiprid, thiacloprid, clothianidin, and imidacloprid. We used fortified chick carcass samples to validate method accuracy (80–125% recoveries), precision (<20% relative standard deviation), and sensitivity (≤1.2 ppb) for these targeted analytes. This method also uses full-scan, high-resolution MS to screen for the presence of a wide variety of other xenobiotics in bird carcasses. The utility of our screening process was demonstrated by the detection of carbaryl in some samples. This sensitive LC-HRMS analytical method for insecticide detection in a matrix of homogenized carcass is ideal for evaluating small birds for insecticide exposure. This novel whole-carcass method may allow for research studies of small-bodied, free-ranging avian species, and could provide insight regarding their exposure to multiple classes of environmental contaminants.

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Kelman, Megan J., Justin B. Renaud, Keith A. Seifert, Jonathan Mack, Ken K. C. Yeung, and Mark W. Sumarah. "Chemotaxonomic Profiling of Canadian Alternaria Populations Using High-Resolution Mass Spectrometry." Metabolites 10, no. 6 (June 9, 2020): 238. http://dx.doi.org/10.3390/metabo10060238.

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Alternaria spp. occur as plant pathogens worldwide under field and storage conditions. They lead to food spoilage and also produce several classes of secondary metabolites that contaminate the food production chain. From a food safety perspective, the major challenge of assessing the risk of Alternaria contamination is the lack of a clear consensus on their species-level taxonomy. Furthermore, there are currently no reliable DNA sequencing methods to allow for differentiation of the toxigenic potential of these fungi. Our objective was to determine which species of Alternaria exist in Canada, and to describe the compounds they make. To address these issues, we performed metabolomic profiling using liquid chromatography high-resolution mass spectrometry (LC-HRMS) on 128 Canadian strains of Alternaria to determine their chemotaxonomy. The Alternaria strains were analyzed using principal component analysis (PCA) and unbiased k-means clustering to identify metabolites with significant differences (p < 0.001) between groups. Four populations or ‘chemotypes’ were identified within the strains studied, and several known secondary metabolites of Alternaria were identified as distinguishing metabolites, including tenuazonic acid, phomapyrones, and altenuene. Though species-level identifications could not be concluded for all groups through metabolomics alone, A. infectoria was able to be identified as a distinct population.

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Astudillo-Pascual, Marina, Irene Domínguez, Pedro A. Aguilera, and Antonia Garrido Frenich. "New Phenolic Compounds in Posidonia oceanica Seagrass: A Comprehensive Array Using High Resolution Mass Spectrometry." Plants 10, no. 5 (April 25, 2021): 864. http://dx.doi.org/10.3390/plants10050864.

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The studies on the Posidonia oceanica Delile (P. oceanica) phenolic composition have been focused on the foliar tissues and have often neglected the phenolic compounds in rhizomes or roots alike. With the current improvements in high resolution mass spectrometry (HRMS) analyzers, such as the Orbitrap MS, there is a new opportunity to more deeply study P. oceanica. One of the benefits is the possibility of conducting an exhaustive phenolic monitoring, which is crucial in the search for new stressor-specific biomarkers of coastal deterioration. For this purpose, the different tissues (leaf, rhizome, and root) of P. oceanica seagrass from several marine sampling areas were analyzed through target, suspected, and non-target screenings. This paper brings a fast and tissues-specific extraction, as well as a detection method of phenolic compounds applying for the first time the potential of HRMS (Exactive Orbitrap) in P. oceanica samples. As a result, 42 phenolic compounds were satisfactorily detected, of which, to our knowledge, 24 were not previously reported in P. oceanica, such as naringenin, naringenin chalcone and pinocembrin, among others. Information here reported could be used for the evaluation of new stressor-specific biomarkers of coastal deterioration in the Mediterranean waters. Furthermore, the followed extraction and analytical method could be considered as a reference protocol in other studies on marine seagrasses due to the exhaustive search and satisfactory results.

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Haq, Kautsar, Mareta Liawati, Abdulloh Abdulloh, and Hery Suwito. "5-(4-Bromophenyl)-7-(2,4-dimethoxyphenyl)-4,7-dihydrotetrazolo[1,5-a]pyrimidine." Molbank 2018, no. 4 (December 17, 2018): M1037. http://dx.doi.org/10.3390/m1037.

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A derivative of dihydrotetrazolopyrimidine has been successfully synthesized through a cyclocondensation reaction between a chalcone derivative with 5-aminotetrazole. The molecular structure of the title compound was established based on Fourier transform infrared spectra (FTIR), high-resolution mass spectrometry (HRMS), 1D and 2D nuclear magnetic resonance (NMR) spectrum.

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Feith, André, Attila Teleki, Michaela Graf, Lorenzo Favilli, and Ralf Takors. "HILIC-Enabled 13C Metabolomics Strategies: Comparing Quantitative Precision and Spectral Accuracy of QTOF High- and QQQ Low-Resolution Mass Spectrometry." Metabolites 9, no. 4 (April 2, 2019): 63. http://dx.doi.org/10.3390/metabo9040063.

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Dynamic 13C-tracer-based flux analyses of in vivo reaction networks still require a continuous development of advanced quantification methods applying state-of-the-art mass spectrometry platforms. Utilizing alkaline HILIC chromatography, we adapt strategies for a systematic quantification study in non- and 13C-labeled multicomponent endogenous Corynebacterium glutamicum extracts by LC-QTOF high resolution (HRMS) and LC-QQQ tandem mass spectrometry (MS/MS). Without prior derivatization, a representative cross-section of 17 central carbon and anabolic key intermediates were analyzed with high selectivity and sensitivity under optimized ESI-MS settings. In column detection limits for the absolute quantification range were between 6.8–304.7 (QQQ) and 28.7–881.5 fmol (QTOF) with comparable linearities (3–5 orders of magnitude) and enhanced precision using QQQ-MRM detection. Tailor-made preparations of uniformly (U)13C-labeled cultivation extracts for isotope dilution mass spectrometry enabled the accurate quantification in complex sample matrices and extended linearities without effect on method parameters. Furthermore, evaluation of metabolite-specific m+1-to-m+0 ratios (ISR1:0) in non-labeled extracts exhibited sufficient methodical spectral accuracies with mean deviations of 3.89 ± 3.54% (QTOF) and 4.01 ± 3.01% (QQQ). Based on the excellent HILIC performance, conformity analysis of time-resolved isotopic enrichments in 13C-tracer experiments revealed sufficient spectral accuracy for QQQ-SIM detection. However, only QTOF-HRMS ensures determination of the full isotopologue space in complex matrices without mass interferences.

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Katahira, Takehiro, Akio Kanazawa, Mai Shinohara, Mami Koshibu, Hideyoshi Kaga, Tomoya Mita, Yuka Tosaka, et al. "Postprandial Plasma Glucagon Kinetics in Type 2 Diabetes Mellitus: Comparison of Immunoassay and Mass Spectrometry." Journal of the Endocrine Society 3, no. 1 (October 26, 2018): 42–51. http://dx.doi.org/10.1210/js.2018-00142.

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Abstract Context Accurate glucagon level measurements are necessary for investigation of mechanisms for postprandial hyperglycemia in type 2 diabetes. Objective To evaluate the accuracy of postprandial glucagon level measurements using a sandwich ELISA vs a recently established liquid chromatography-high resolution mass spectrometry (LC-HRMS) method in type 2 diabetes mellitus. Design and Participants Twenty patients with type 2 diabetes treated with insulin underwent a meal test before and after administration of the dipeptidyl peptidase-4 inhibitor anagliptin for 4 weeks. Blood samples were taken serially after the meal, and glucagon levels were measured using both ELISA and LC-HRMS. We compared the change from baseline to 4 weeks (Δ0–4W) using the area under the curve for plasma glucagon during the meal test [area under the curve (AUC)0–3h] measured using ELISA and LC-HRMS. Results ELISA-based glucagon AUC0–3h was higher than LC-HRMS–based AUC0–3h at baseline and 4 weeks. However, differences in Δ0–4W-AUC0–3h measured using ELISA and LC-HRMS were not statistically significant. Additionally, Δ0–4W-AUC0–3h measured using ELISA and LC-HRMS were strongly correlated (r = 0.87, P < 0.001). Conclusions Plasma glucagon levels during a meal test in patients with type 2 diabetes measured using ELISA were consistently higher than those measured using LC-HRMS. However, given that the changes in glucagon levels measured using ELISA before and after dipeptidyl peptidase-4 inhibitor therapy were similar to those based on LC-HRMS, this ELISA seems to be useful for evaluating the effect of the drug interventions on postprandial glucagon levels.

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Mahale, Vishal, Ajeet Singh, Gayatri S. Phadke, Avinash D. Ghanate, Dasharath P. Oulkar, Kaushik Banerjee, and Venkateswarlu Panchagnula. "Determination of Triazines and Triazoles in Grapes Using Atmospheric Pressure Matrix-Assisted Laser Desorption/Ionization High-Resolution Mass Spectrometry." Journal of AOAC INTERNATIONAL 100, no. 3 (May 1, 2017): 640–46. http://dx.doi.org/10.5740/jaoacint.17-0047.

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Abstract A chromatography-free atmospheric pressure matrix-assisted laser desorption/ionization high-resolution massspectrometry (AP-MALDI HRMS) method is described for the simultaneous and quantitative detection of triazines and triazoles in grapes. The analytes were detected reproducibly with high mass accuracy (mass error within 5 ppm) and further confirmed by collision-induced dissociation fragmentation in tandem MS. The LODs and LOQs forall the analytes were found to be in the nanogram per gram level (15–20 ng/g LOQ). Internal standard–normalized high-resolution accurate mass–extracted (HR-AM) peak intensities of the detected ions were used to generate the concentration response curves. Linearity (with R2 values around 0.99) was obtained for these curves within a concentration range of 20–200 ng/g of the individual analytes. The accuracy and precision of the method were further established using QC samples. Validation and performancecomparison of the AP-MALDI HRMS method with an existing standard method using LC with triple quadrupole MS was carried out (evaluating sensitivity, accuracy, precision, and analysis time) using 20 table-grape field samples after QuEChERS extraction.

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Jensen, de Boevre, Preußke, de Saeger, Birr, Verreet, and Sönnichsen. "Evaluation of High-Resolution Mass Spectrometry for the Quantitative Analysis of Mycotoxins in Complex Feed Matrices." Toxins 11, no. 9 (September 12, 2019): 531. http://dx.doi.org/10.3390/toxins11090531.

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The selective and sensitive analysis of mycotoxins in highly complex feed matrices is a great challenge. In this study, the suitability of OrbitrapTM-based high-resolution mass spectrometry (HRMS) for routine mycotoxin analysis in complex feeds was demonstrated by the successful validation of a full MS/data-dependent MS/MS acquisition method for the quantitative determination of eight Fusarium mycotoxins in forage maize and maize silage according to the Commission Decision 2002/657/EC. The required resolving power for accurate mass assignments (<5 ppm) was determined as 35,000 full width at half maximum (FWHM) and 70,000 FWHM for forage maize and maize silage, respectively. The recovery (RA), intra-day precision (RSDr), and inter-day precision (RSDR) of measurements were in the range of 94 to 108%, 2 to 16%, and 2 to 12%, whereas the decision limit (CCα) and the detection capability (CCβ) varied from 11 to 88 µg/kg and 20 to 141 µg/kg, respectively. A set of naturally contaminated forage maize and maize silage samples collected in northern Germany in 2017 was analyzed to confirm the applicability of the HRMS method to real samples. At least four Fusarium mycotoxins were quantified in each sample, highlighting the frequent co-occurrence of mycotoxins in feed.

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Ríos Peces, Sandra, Caridad Díaz Navarro, Cristina Márquez López, Octavio Caba, Cristina Jiménez-Luna, Consolación Melguizo, José Carlos Prados, Olga Genilloud, Francisca Vicente Pérez, and José Pérez del Palacio. "Untargeted LC-HRMS-Based Metabolomics for Searching New Biomarkers of Pancreatic Ductal Adenocarcinoma: A Pilot Study." SLAS DISCOVERY: Advancing the Science of Drug Discovery 22, no. 4 (September 27, 2016): 348–59. http://dx.doi.org/10.1177/1087057116671490.

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Pancreatic ductal adenocarcinoma is one of the most lethal tumors since it is usually detected at an advanced stage in which surgery and/or current chemotherapy have limited efficacy. The lack of sensitive and specific markers for diagnosis leads to a dismal prognosis. The purpose of this study is to identify metabolites in serum of pancreatic ductal adenocarcinoma patients that could be used as diagnostic biomarkers of this pathology. We used liquid chromatography–high-resolution mass spectrometry for a nontargeted metabolomics approach with serum samples from 28 individuals, including 16 patients with pancreatic ductal adenocarcinoma and 12 healthy controls. Multivariate statistical analysis, which included principal component analysis and partial least squares, revealed clear separation between the patient and control groups analyzed by liquid chromatography–high-resolution mass spectrometry using a nontargeted metabolomics approach. The metabolic analysis showed significantly lower levels of phospholipids in the serum from patients with pancreatic ductal adenocarcinoma compared with serum from controls. Our results suggest that the liquid chromatography–high-resolution mass spectrometry–based metabolomics approach provides a potent and promising tool for the diagnosis of pancreatic ductal adenocarcinoma patients using the specific metabolites identified as novel biomarkers that could be used for an earlier detection and treatment of these patients.

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Lee, Jisun H. J., and Jiangjiang Zhu. "Optimizing Secondary Electrospray Ionization High-Resolution Mass Spectrometry (SESI-HRMS) for the Analysis of Volatile Fatty Acids from Gut Microbiome." Metabolites 10, no. 9 (August 28, 2020): 351. http://dx.doi.org/10.3390/metabo10090351.

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Gut microbiota plays essential roles in maintaining gut homeostasis. The composition of gut microbes and their metabolites are altered in response to diet and remedial agents such as antibiotics. However, little is known about the effect of antibiotics on the gut microbiota and their volatile metabolites. In this study, we evaluated the impact of a moderate level of ampicillin treatment on volatile fatty acids (VFAs) of gut microbial cultures using an optimized real-time secondary electrospray ionization coupled with high-resolution mass spectrometry (SESI-HRMS). To evaluate the ionization efficiency, different types of electrospray solvents and concentrations of formic acid as an additive (0.01, 0.05, and 0.1%, v/v) were tested using VFAs standard mixture (C2–C7). As a result, the maximum SESI-HRMS signals of all studied m/z values were observed from water with 0.01% formic acid than those from the aqueous methanolic solutions. Optimal temperatures of sample inlet and ion chamber were set at 130 °C and 85 °C, respectively. SESI spray pressure at 0.5 bar generated the maximum intensity than other tested values. The optimized SESI-HRMS was then used for the analysis of VFAs in gut microbial cultures. We detected that the significantly elevated C4 and C7 VFAs in the headspace of gut microbial cultures six hours after ampicillin treatment (1 mg/L). In conclusion, our results suggested that the optimized SESI-HRMS method can be suitable for the analysis of VFAs from gut microbes in a rapid, sensitive, and non-invasive manner.

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Roy-Lachapelle, Audrey, Sung Vo Duy, Gabriel Munoz, Quoc Tuc Dinh, Emmanuelle Bahl, Dana F. Simon, and Sébastien Sauvé. "Analysis of multiclass cyanotoxins (microcystins, anabaenopeptins, cylindrospermopsin and anatoxins) in lake waters using on-line SPE liquid chromatography high-resolution Orbitrap mass spectrometry." Analytical Methods 11, no. 41 (2019): 5289–300. http://dx.doi.org/10.1039/c9ay01132c.

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An on-line SPE-UHPLC-HRMS method was optimized for filtration, on-line SPE, and HRMS conditions for the rapid screening of 17 cyanotoxins. 8 cyanotoxins were detected with 75% of lakes containing MC-LR and 38% containing anabaenopeptins (A or B).

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Millard, Pierre, Baudoin Delépine, Matthieu Guionnet, Maud Heuillet, Floriant Bellvert, and Fabien Létisse. "IsoCor: isotope correction for high-resolution MS labeling experiments." Bioinformatics 35, no. 21 (March 23, 2019): 4484–87. http://dx.doi.org/10.1093/bioinformatics/btz209.

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Abstract Summary Mass spectrometry (MS) is widely used for isotopic studies of metabolism and other (bio)chemical processes. Quantitative applications in systems and synthetic biology require to correct the raw MS data for the contribution of naturally occurring isotopes. Several tools are available to correct low-resolution MS data, and recent developments made substantial improvements by introducing resolution-dependent correction methods, hence opening the way to the correction of high-resolution MS (HRMS) data. Nevertheless, current HRMS correction methods partly fail to determine which isotopic species are resolved from the tracer isotopologues and should thus be corrected. We present an updated version of our isotope correction software (IsoCor) with a novel correction algorithm which ensures to accurately exploit any chemical species with any isotopic tracer, at any MS resolution. IsoCor v2 also includes a novel graphical user interface for intuitive use by end-users and a command-line interface to streamline integration into existing pipelines. Availability and implementation IsoCor v2 is implemented in Python 3 and was tested on Windows, Unix and MacOS platforms. The source code and the documentation are freely distributed under GPL3 license at https://github.com/MetaSys-LISBP/IsoCor/ and https://isocor.readthedocs.io/.

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Gonsalves, Michelle D., Alexander Yevdokimov, Audreyana Brown-Nash, James L. Smith, and Jimmie C. Oxley. "Paper spray ionization–high-resolution mass spectrometry (PSI-HRMS) of peroxide explosives in biological matrices." Analytical and Bioanalytical Chemistry 413, no. 11 (March 15, 2021): 3069–79. http://dx.doi.org/10.1007/s00216-021-03244-4.

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Arju, Georg, Anastassia Taivosalo, Dmitri Pismennoi, Taivo Lints, Raivo Vilu, Zanda Daneberga, Svetlana Vorslova, Risto Renkonen, and Sakari Joenvaara. "Application of the UHPLC-DIA-HRMS Method for Determination of Cheese Peptides." Foods 9, no. 8 (July 23, 2020): 979. http://dx.doi.org/10.3390/foods9080979.

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Until now, cheese peptidomics approaches have been criticised for their lower throughput. Namely, analytical gradients that are most commonly used for mass spectrometric detection are usually over 60 or even 120 min. We developed a cheese peptide mapping method using nano ultra-high-performance chromatography data-independent acquisition high-resolution mass spectrometry (nanoUHPLC-DIA-HRMS) with a chromatographic gradient of 40 min. The 40 min gradient did not show any sign of compromise in milk protein coverage compared to 60 and 120 min methods, providing the next step towards achieving higher-throughput analysis. Top 150 most abundant peptides passing selection criteria across all samples were cross-referenced with work from other publications and a good correlation between the results was found. To achieve even faster sample turnaround enhanced DIA methods should be considered for future peptidomics applications.

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Marchei, Emilia, Maria Alias Ferri, Marta Torrens, Magí Farré, Roberta Pacifici, Simona Pichini, and Manuela Pellegrini. "Ultra-High Performance Liquid Chromatography-High Resolution Mass Spectrometry and High-Sensitivity Gas Chromatography-Mass Spectrometry Screening of Classic Drugs and New Psychoactive Substances and Metabolites in Urine of Consumers." International Journal of Molecular Sciences 22, no. 8 (April 13, 2021): 4000. http://dx.doi.org/10.3390/ijms22084000.

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The use of the new psychoactive substances is continuously growing and the implementation of accurate and sensible analysis in biological matrices of users is relevant and fundamental for clinical and forensic purposes. Two different analytical technologies, high-sensitivity gas chromatography-mass spectrometry (GC-MS) and ultra-high-performance liquid chromatography-high-resolution mass spectrometry (UHPLC-HRMS) were used for a screening analysis of classic drugs and new psychoactive substances and their metabolites in urine of formed heroin addicts under methadone maintenance therapy. Sample preparation involved a liquid-liquid extraction. The UHPLC-HRMS method included Accucore™ phenyl Hexyl (100 × 2.1 mm, 2.6 μm, Thermo, USA) column with a gradient mobile phase consisting of mobile phase A (ammonium formate 2 mM in water, 0.1% formic acid) and mobile phase B (ammonium formate 2 mM in methanol/acetonitrile 50:50 (v/v), 0.1% formic acid) and a full-scan data-dependent MS2 (ddMS2) mode for substances identification (mass range 100–1000 m/z). The GC-MS method employed an ultra-Inert Intuvo GC column (HP-5MS UI, 30 m, 250 µm i.d, film thickness 0.25 µm; Agilent Technologies, Santa Clara, CA, USA) and electron-impact (EI) mass spectra were recorded in total ion monitoring mode (scan range 40–550 m/z). Urine samples from 296 patients with a history of opioid use disorder were examined. Around 80 different psychoactive substances and/or metabolites were identified, being methadone and metabolites the most prevalent ones. The possibility to screen for a huge number of psychotropic substances can be useful in suspected drug related fatalities or acute intoxication/exposure occurring in emergency departments and drug addiction services.

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Milman, B. L., and I. K. Zhurkovich. "Present-Day Practice of Non-Target Chemical Analysis." Journal of Analytical Chemistry 77, no. 5 (May 2022): 537–49. http://dx.doi.org/10.1134/s1061934822050070.

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Abstract We review the main techniques, procedures, and information products used in non-target analysis (NTA) to reveal the composition of substances. Sampling and sample preparation methods are preferable that ensure the extraction of analytes from test samples in a wide range of analyte properties with the most negligible loss. The necessary techniques of analysis are versions of chromatography–high-resolution tandem mass spectrometry (HRMS), yielding individual characteristics of analytes (mass spectra, retention properties) to accurately identify them. The prioritization of the analytical strategy discards unnecessary measurements and thereby increases the performance of the NTA. Chemical databases, collections of reference mass spectra and retention characteristics, algorithms, and software for processing HRMS data are indispensable in NTA.

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Bravi, Viviana S., Sandra Castello, and Luis Bruno-Blanch. "Phytochemical preliminary study of hexane fractions of leaves of Eugenia uniflora L. (Myrtaceae)." Boletin Latinoamericano y del Caribe de Plantas Medicinales y Aromaticas 22, no. 1 (January 30, 2023): 86–99. http://dx.doi.org/10.37360/blacpma.23.22.1.7.

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Fractions from the Hexane Extract (HE) of Eugenia unifloraL. leaves were subjected to various chromatographic systems. Germacrone sesquiterpene and bornyl acetate bicyclic ester were characterized by High Performance Liquid Chromatography coupled to Mass Spectrometry (HPLC-MS) with APCI Mass detector comparing with their homonymous spectrum provided by databases and characteristic fragmentation pathways were proposed. The monoterpene pulegone and the pentacyclic triterpene compound, ursolic acid, were found through High Performance Liquid Chromatography coupled to High Resolution Mass Spectrometry (HPLC -HRMS) by atmospheric pressure ionization (API) and the detector used was mass of Electronic Impact (IE). Both ursolic acid and bornyl acetate are present in other species of the same genus, but not in the species studied.

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Banskota, Arjun H., Alysson Jones, Joseph P. M. Hui, Roumiana Stefanova, and Ian W. Burton. "Analysis of Polar Lipids in Hemp (Cannabis sativa L.) By-Products by Ultra-High Performance Liquid Chromatography and High-Resolution Mass Spectrometry." Molecules 27, no. 18 (September 9, 2022): 5856. http://dx.doi.org/10.3390/molecules27185856.

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Polar lipids were extracted from residual biomass of hemp (Cannabis sativa L.) by-products with EtOH and partitioned into aqueous and chloroform fractions. The chloroform fractions were studied for their lipid composition using solid-phase extraction (SPE) followed by UHPLC/HRMS and NMR analyses. The 1H NMR and gravimetric yield of SPE indicated triacylglycerols covered ≥ 51.3% of the chloroform fraction of hemp seed hulls and hemp cake. UHPLC/HRMS analyses of remaining polar lipids led to the identification of nine diacylglycerols (DAGs), six lysophosphatidylcholines (LPCs), five lysophosphatidylethanolamines (LPEs), eight phosphatidylethanolamines (PEs), and thirteen phosphatidylcholines (PCs) for the first time from hemp seed hulls. The regiospecificity of fatty acyl substitutes in glycerol backbone of individual phospholipids were assigned by analyzing the diagnostic fragment ions and their intensities. The heat-map analysis suggested that DAG 18:2/18:2, 1-LPC 18:2, 1-LPE 18:2, PE 18:2/18:2, and PC 18:2/18:2 were the predominant molecules within their classes, supported by the fact that linoleic acid was the major fatty acid covering > 41.1% of the total fatty acids determined by GC-FID analysis. The 31P NMR analysis confirmed the identification of phospholipids and suggested PC covers ≥ 37.9% of the total phospholipid present in hemp by-products. HPLC purification led to the isolation of 1,2-dilinoleoylphosphatidylcholine and 1-palmitoyl-2-linoleoylphosphatidylcholine. These two major PCs further confirmed the UHPLC/HRMS finding.

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Hong, Junting, Nadia Boussetta, Gérald Enderlin, Nabil Grimi, and Franck Merlier. "Real-Time Monitoring of the Atrazine Degradation by Liquid Chromatography and High-Resolution Mass Spectrometry: Effect of Fenton Process and Ultrasound Treatment." Molecules 27, no. 24 (December 17, 2022): 9021. http://dx.doi.org/10.3390/molecules27249021.

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High resolution mass spectrometry (HRMS) was coupled with ultra-high-performance liquid chromatography (uHPLC) to monitor atrazine (ATZ) degradation process of Fenton/ultrasound (US) treatment in real time. Samples were automatically taken through a peristaltic pump, and then analysed by HPLC-HRMS. The injection in the mass spectrometer was performed every 4 min for 2 h. ATZ and its degradation metabolites were sampled and identified. Online Fenton experiments in different equivalents of Fenton reagents, online US experiments with/without Fe2+ and offline Fenton experiments were conducted. Higher equivalents of Fenton reagents promoted the degradation rate of ATZ and the generation of the late-products such as Ammeline (AM). Besides, adding Fe2+ accelerated ATZ degradation in US treatment. In offline Fenton, the degradation rate of ATZ was higher than that of online Fenton, suggesting the offline samples were still reacting in the vial. The online analysis precisely controls the effect of reagents over time through automatic sampling and rapid detection, which greatly improves the measurement accuracy. The experimental set up proposed here both prevents the degradation of potentially unstable metabolites and provides a good way to track each metabolite.

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Montoya-Aguilera, Julia, Jeremy R. Horne, Mallory L. Hinks, Lauren T. Fleming, Véronique Perraud, Peng Lin, Alexander Laskin, Julia Laskin, Donald Dabdub, and Sergey A. Nizkorodov. "Secondary organic aerosol from atmospheric photooxidation of indole." Atmospheric Chemistry and Physics 17, no. 18 (September 28, 2017): 11605–21. http://dx.doi.org/10.5194/acp-17-11605-2017.

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Abstract. Indole is a heterocyclic compound emitted by various plant species under stressed conditions or during flowering events. The formation, optical properties, and chemical composition of secondary organic aerosol (SOA) formed by low-NOx photooxidation of indole were investigated. The SOA yield (1. 3 ± 0. 3) was estimated from measuring the particle mass concentration with a scanning mobility particle sizer (SMPS) and correcting it for wall loss effects. The high value of the SOA mass yield suggests that most oxidized indole products eventually end up in the particle phase. The SOA particles were collected on filters and analysed offline with UV–vis spectrophotometry to measure the mass absorption coefficient (MAC) of the bulk sample. The samples were visibly brown and had MAC values of ∼ 2 m2 g−1 at λ = 300 nm and ∼ 0. 5 m2 g−1 at λ = 400 nm, comparable to strongly absorbing brown carbon emitted from biomass burning. The chemical composition of SOA was examined with several mass spectrometry methods. Direct analysis in real-time mass spectrometry (DART-MS) and nanospray desorption electrospray high-resolution mass spectrometry (nano-DESI-HRMS) were both used to provide information about the overall distribution of SOA compounds. High-performance liquid chromatography, coupled to photodiode array spectrophotometry and high-resolution mass spectrometry (HPLC-PDA-HRMS), was used to identify chromophoric compounds that are responsible for the brown colour of SOA. Indole derivatives, such as tryptanthrin, indirubin, indigo dye, and indoxyl red, were found to contribute significantly to the visible absorption spectrum of indole SOA. The potential effect of indole SOA on air quality was explored with an airshed model, which found elevated concentrations of indole SOA during the afternoon hours contributing considerably to the total organic aerosol under selected scenarios. Because of its high MAC values, indole SOA can contribute to decreased visibility and poor air quality.

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Núñez, Nerea, Oscar Vidal-Casanella, Sonia Sentellas, Javier Saurina, and Oscar Núñez. "Non-Targeted Ultra-High Performance Liquid Chromatography-High-Resolution Mass Spectrometry (UHPLC-HRMS) Fingerprints for the Chemometric Characterization and Classification of Turmeric and Curry Samples." Separations 7, no. 2 (June 10, 2020): 32. http://dx.doi.org/10.3390/separations7020032.

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In this work, non-targeted ultra-high performance liquid chromatography-high-resolution mass spectrometry (UHPLC-HRMS) fingerprints obtained by C18 reversed-phase chromatography were proposed as sample chemical descriptors for the characterization and classification of turmeric and curry samples. A total of 21 turmeric and 9 curry commercially available samples were analyzed in triplicate after extraction with dimethyl sulfoxide (DMSO). The results demonstrated the feasibility of non-targeted UHPLC-HRMS fingerprints for sample classification, showing very good classification capabilities by partial least squares regression-discriminant analysis (PLS-DA), with 100% classification rates being obtained by PLS-DA when randomly selected samples were processed as “unknown” ones. Besides, turmeric curcuma species (Curcuma longa vs. Curcuma zedoaria) and turmeric Curcuma longa varieties (Madras, Erodes, and Alleppey) discrimination was also observed by PLS-DA when using the proposed fingerprints as chemical descriptors. As a conclusion, non-targeted UHPLC-HRMS fingerprinting is a suitable methodology for the characterization, classification, and authentication of turmeric and curry samples, without the requirement of using commercially available standards for quantification nor the necessity of metabolite identification.

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Slobodchikova, Irina, Reajean Sivakumar, Md Samiur Rahman, and Dajana Vuckovic. "Characterization of Phase I and Glucuronide Phase II Metabolites of 17 Mycotoxins Using Liquid Chromatography—High-Resolution Mass Spectrometry." Toxins 11, no. 8 (July 24, 2019): 433. http://dx.doi.org/10.3390/toxins11080433.

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Routine mycotoxin biomonitoring methods do not include many mycotoxin phase I and phase II metabolites, which may significantly underestimate mycotoxin exposure especially for heavily metabolized mycotoxins. Additional research efforts are also needed to measure metabolites in vivo after exposure and to establish which mycotoxin metabolites should be prioritized for the inclusion during large-scale biomonitoring efforts. The objective of this study was to perform human in vitro microsomal incubations of 17 mycotoxins and systematically characterize all resulting metabolites using liquid chromatography–high-resolution mass spectrometry (LC-HRMS). The results obtained were then used to build a comprehensive LC-MS library and expand a validated 17-mycotoxin method for exposure monitoring to screening of additional 188 metabolites, including 100 metabolites reported for the first time. The final method represents one of the most comprehensive LC-HRMS methods for mycotoxin biomonitoring or metabolism/fate studies.

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Dahibhate, Nilesh Lakshman, and Kundan Kumar. "Metabolite profiling of Bruguiera cylindrica reveals presence of potential bioactive compounds." PeerJ Analytical Chemistry 4 (May 4, 2022): e16. http://dx.doi.org/10.7717/peerj-achem.16.

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Bruguiera cylindrica parts are commonly used in Chinese and Indian traditional medicine to treat diarrhea, fever, and many ailments. The present study aims non targeted analysis of key secondary metabolites of B. cylindrica by gas chromatography mass spectrometry (GC-MS) and ultra-high performance liquid chromatography hybrid quadrupole-Exactive-Orbitrap high resolution mass spectrometry (UHPLC-Q-Exactive Orbitrap HRMS). GC-MS and UHPLC-Q-Exactive Orbitrap HRMS were utilized for metabolic profiling of ethyl acetate extract of B. cylindrica leaves. Key metabolites in the extract were identified and predicted based on chemical similarity using online databases such as ChemSpider and mzCloud. Thirty-six compounds belonging to different classes of secondary metabolites viz. flavonoids, fatty acids, fatty acid amides, carboxylic acids, and alkaloids were identified in the extract. Pentacyclic triterpenes like betulin, ursolic acid and a tropine, an alkaloid with potential pharmacological and therapeutic activities such as anticancer properties, neuromuscular blockers and antioxidants, were also identified. This study combined GC-MS and UHPLC-Q-Exactive Orbitrap HRMS with available online database for effective and rapid identification of bioactive metabolites in the ethyl acetate extract of mangrove without individual standard application. This is the first report on the HRMS based secondary metabolic profiling of B. cylindrica, with comprehensive map of its biologically important metabolites.

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Aksenova, Liliya V., Vladimir V. Koval, and Alexander A. Chernonosov. "Parallel Reaction Monitoring Mode for Atenolol Quantification in Dried Plasma Spots by Liquid Chromatography Coupled with High-Resolution Mass Spectrometry." Processes 10, no. 7 (June 22, 2022): 1240. http://dx.doi.org/10.3390/pr10071240.

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In this study, we reported a rapid, sensitive, robust, and validated method for atenolol quantification in dried plasma spots (DPS) by liquid chromatography with high-resolution mass spectrometry (LC-HRMS) using parallel reaction monitoring mode (PRM). Aliquots of 25 µL human plasma were placed onto Whatman 903 Cards and air-dried. Disks (3.2 mm internal diameter) were punched, and a 100 µL working internal standard solution was added to each sample and then incubated on a shaker for 15 min at 40 °C, followed by rapid centrifugation (10,000× g, 10 s). The supernatant was transferred into 300 µL vials for subsequent LC–HRMS analysis. After chromatographic separation, atenolol and the internal standard were quantified in positive-ion parallel reaction monitoring mode by detection of all target product ions at 10 ppm tolerances. The total time of the analysis was 5 min. The calibration curve was linear in the range of 5–1000 ng/mL with interday and intraday precision levels and biases of <14.4%, and recovery was 62.9–81.0%. The atenolol in DPS was stable for ≥30 days at 25 and 4 °C. This fully validated method is selective and suitable for atenolol quantitation in DPS using LC–HRMS.

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Journal articles on the topic 'High resolution mass spectrometry (HRMS)'

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