Rapid Communications in Mass Spectrometry最新文献

{"title":"Pretreatment method for oxygen stable isotope ratio analysis of the sugar-rich fraction in fruit juice via isotope ratio mass spectrometry","authors":"Ayano Watanabe,&nbsp;Shoichi Terada","doi":"10.1002/rcm.9906","DOIUrl":"10.1002/rcm.9906","url":null,"abstract":"<div>\u0000 \u0000 <section>\u0000 \u0000 <h3> Rationale</h3>\u0000 \u0000 <p>The oxygen stable isotope ratio (δ¹⁸O) of the sugar-rich fraction of fruit juice is important as a tracer of the geographical origin of raw material. This study sought to minimize the inter-day variation of δ¹⁸O attributable to the influence of water to accurately monitor geographical origin labeling.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>Two drying devices (freeze dryer and vacuum oven) were compared. Then, two humidity levels (normal and low humidity) at which the samples were placed after drying were compared. The low-humidity environment was constructed using a glove bag and pure argon gas. δ¹⁸O was measured using thermal conversion elemental analyzer/isotope ratio mass spectrometry. Improvements were made to the measurement method based on aforementioned analyses results, and the performance of the initial and improved methods was compared.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>δ¹⁸O of juice dried in a vacuum oven was 3.30‰ lower than that of juice dried in a freeze dryer. Moreover, δ¹⁸O of juice samples exposed to normal humidity was 3.74‰ lower than that of samples exposed to low humidity. The combined inter-day and intra-day standard deviation was reduced from 1.20‰ in the initial method to 0.42‰ in the improved method.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>This study describes a pretreatment method for δ¹⁸O measurement in the sugar-rich fraction of fruit juice with less inter-day variation, and it will be useful for monitoring geographical origin labeling.</p>\u0000 </section>\u0000 </div>","PeriodicalId":225,"journal":{"name":"Rapid Communications in Mass Spectrometry","volume":"38 22","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142124305","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Exploring methandienone metabolites generated via homogenized camel liver: Advancements for anti-doping applications through High Resolution-Liquid Chromatography Mass Spectrometry analysis","authors":"Ramees Abdulla Vazhat,&nbsp;N. A. Mohamed Farook,&nbsp;Jahfar Nalakath,&nbsp;Praseen Ondern Komathu","doi":"10.1002/rcm.9902","DOIUrl":"10.1002/rcm.9902","url":null,"abstract":"<div>\u0000 \u0000 <section>\u0000 \u0000 <h3> Rationale</h3>\u0000 \u0000 <p>Anabolic steroids, also known as anabolic–androgenic steroids (AAS), encompass steroidal androgens such as testosterone, as well as synthetic counterparts with similar structures and effects. The misuse of AAS has increased over the years, leading to ethical and welfare concerns in sports. The World Anti-Doping Agency (WADA) and the International Federation for Equestrian Sports (FEI) have banned AAS in relevant sports. Methandienone is one of the most identified anabolic androgenic steroids in sports drug testing, Therefore, reliable detection methods are crucial for effective doping control and maintaining the integrity of the sports.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>This study explores the use of homogenized camel liver for detecting methandienone metabolites in camels. The biotransformation pathways of methandienone in homogenized camel liver tissues are analyzed using Liquid Chromatography-High Resolution Mass Spectrometry (LC-HRMS) to identify and characterize the phase I and phase II metabolites. Chromatographic separation was achieved using a Thermo-Hypersil C18 column.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>The study has identified 11 methandienone metabolites (M1–M11), this includes 10 phase I and one phase II metabolite. A glucuronic acid conjugate of methandienone was observed in this study, but no sulfonic acid conjugations were found. The metabolites and their possible chemical structures, along with their fragmentation patterns are confirmed using MSMS (MS2) experiments in data-independent acquisition (DIA) mode.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>These findings serve as a vital tool for the rapid detection of methandienone, combating its illicit use in camel racing. Comprehensive screenings covering both the parent drug and its metabolites are recommended to improve detection accuracy and ensure regulatory compliance in sports doping. Future research should explore methandienone's metabolite profile in administered camel samples.</p>\u0000 </section>\u0000 </div>","PeriodicalId":225,"journal":{"name":"Rapid Communications in Mass Spectrometry","volume":"38 22","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142124304","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Qualitative and quantitative characterization of elastin-like polypeptides combining low-PH/low-temperature bottom-up and intact protein liquid chromatography mass spectrometric analysis","authors":"André Vente,&nbsp;Marija Mladic,&nbsp;Olaf Schouten,&nbsp;Jens Thies,&nbsp;Rob van der Hoeven","doi":"10.1002/rcm.9905","DOIUrl":"10.1002/rcm.9905","url":null,"abstract":"<div>\u0000 \u0000 <section>\u0000 \u0000 <h3> Rationale</h3>\u0000 \u0000 <p>Elastin-like polypeptides (ELPs) are elastic and thermoresponsive biopolymers composed of VPGXG repeats (X can be any amino acid except proline), used in biomedical applications, for example, tissue engineering and drug delivery. As different variants of ELP are mostly produced fermentatively, there is a need for the development of analysis methods that allow for absolute protein quantification in both complex matrices and purified samples and MW determination of the final products.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>ELPs were intracellularly expressed in <i>Escherichia coli</i> quantified after cell lysis and enzymatic digestion using a proline-specific protease ProAlanase (Promega) at acidic conditions. Resulting peptides were separated by liquid chromatography, and mass spectrometry analysis was conducted by electrospray ionization high-resolution mass spectrometry using an Orbitrap mass spectrometer. The addition of a stable isotopically labeled internal standard enabled quantification in complex matrices. Prior to intact mass analysis, ELPs were purified from fermentation broth by inverse temperature cycling. Intact protein analysis was performed using reversed-phase liquid chromatography, and mass spectrometry analysis was conducted by electrospray ionization high-resolution mass spectrometry using a time-of-flight mass spectrometer.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>Absolute quantification of ELPs was achieved by utilizing ELP-specific properties, that is, proline-rich, soluble at low pH and low temperature. The repetitive nature of ELPs allows for sensitivity increase and use of higher dilution factors to minimize the matrix effects. Despite the lack of amino acids with charged side chains (Arg, His, Lys, Asp, and Glu) in ELP, we demonstrated successful intact protein analysis using reversed-phase LC coupled to electrospray ionization TOF MS. Moreover, truncated protein forms could be chromatographically separated and characterized as well as N-terminal modifications.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>Both methods combined enabled quantitative and qualitative characterization of fermentatively produced ELPs.</p>\u0000 </section>\u0000 </div>","PeriodicalId":225,"journal":{"name":"Rapid Communications in Mass Spectrometry","volume":"38 21","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142118579","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modern plants and sulfur isoscapes — A review, discussion, and construction of a pilot δ34S isoscape for mobility and provenance studies","authors":"Damon Tarrant,&nbsp;Michael P. Richards","doi":"10.1002/rcm.9908","DOIUrl":"10.1002/rcm.9908","url":null,"abstract":"<div>\u0000 \u0000 <section>\u0000 \u0000 <h3> RATIONALE</h3>\u0000 \u0000 <p>Sulfur isotopes are increasingly used as mobility indicators in humans and animals in biology, archaeology, and forensics. However, there has been a lack of modern sulfur isotope baseline “isoscape” studies using modern plants and animals, largely due to the possibility of contamination of the S isotope values by modern pollution.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> METHODS</h3>\u0000 \u0000 <p>We collected plants from across a 900-km east–west transect of British Columbia Canada and measured their sulfur isotope values. We then used a random forest model to determine which variables best explained the isotope data patterning and produced a sulfur isoscape for the southern region of British Columbia.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> RESULTS</h3>\u0000 \u0000 <p>We see clear patterning in the plant sulfur isotope values that relate to geographical location and rainfall. Our model also shows that for this study area, it is unlikely that there is a significant influence of anthropogenic pollution on plant <i>δ</i>³⁴S values. We also discuss the use of plants as a substrate for sulfur isoscapes and possible explanations for the often-observed difference between plant and animal <i>δ</i>³⁴S values from the same region, related to differing sources of sulfur in plants compared to amino acids in human and animal tissues.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> CONCLUSIONS</h3>\u0000 \u0000 <p>We found that for areas of the world where sulfur pollution is likely less widespread, it is possible to produce a modern plant S isoscape that should be an accurate baseline for mobility studies. Using random forest modelling, we have produced a baseline sulfur isoscape map of southern British Columbia that can be used for ecology, forensic and archaeological studies.</p>\u0000 </section>\u0000 </div>","PeriodicalId":225,"journal":{"name":"Rapid Communications in Mass Spectrometry","volume":"38 21","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/rcm.9908","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142118577","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optimized liquid chromatography–tandem mass spectrometry protocol for enhanced detection of 45 pesticides in water and soil samples","authors":"Lingchen Meng,&nbsp;Wenrui Yao,&nbsp;Ling Wen,&nbsp;Xiaoli Fu,&nbsp;Yulin Qi,&nbsp;Dietrich A. Volmer","doi":"10.1002/rcm.9904","DOIUrl":"10.1002/rcm.9904","url":null,"abstract":"<div>\u0000 \u0000 <section>\u0000 \u0000 <h3> Rationale</h3>\u0000 \u0000 <p>The development of analytical screening techniques for pesticides is crucial for preventing and mitigating environmental contamination. Mass spectrometry-based screening methods differ based on the complexity of the sample matrix and the diversity of the target compounds. One of the major challenges is balancing cost reduction in the extraction process with the optimization of analytical results. This protocol introduces a universal and efficient scheme for the qualitative and quantitative schemes for 45 pesticides within a single analytical run.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>Water samples were extracted using an SPE column, with the pH adjusted to 7. Soil samples were processed using a modified QuEChERS method. The pretreatment for water samples emphasized selecting appropriate SPE columns and optimizing pH, while for soil samples, the focus was on choosing suitable extraction solvents and extraction salt packages. The enriched samples were then analyzed using liquid chromatography–tandem mass spectrometry (LC–MS/MS). The method was evaluated for accuracy, precision, detection limits, and matrix effects.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>The method enabled the simultaneous detection of 45 pesticides within a 15-minute analysis period. SPE recoveries ranged from 56.1% to 118.8%. Instrumental detection limits varied between 0.02 and 1 pg, while method detection limits extended from 0.05 to 18.47 ng/l in soil and water matrices. The approach was successfully applied to water and soil samples, with the pesticide concentration ranging from 0.1 ng/L to 38 μg/L.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>The protocol substantially enhances the characterization and quantification of 45 pesticides in environmental samples, achieving a remarkable reduction in detection limits by an order of magnitude compared to previous research. This method enables the simultaneous detection of pesticides in both water and soil matrices using a single system, addressing the challenges of using separate systems for different environmental media. Furthermore, this protocol provides a crucial theoretical foundation for managing and safeguarding against pesticide pollution.</p>\u0000 </section>\u0000 </div>","PeriodicalId":225,"journal":{"name":"Rapid Communications in Mass Spectrometry","volume":"38 21","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/rcm.9904","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142118578","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Investigation of the laser fluence and wavelength dependence in surface-assisted laser desorption/ionization mass spectrometry using gold nanoparticles.","authors":"Wendy H Müller, Alexander Potthoff, Klaus Dreisewerd, Jens Soltwisch","doi":"10.1002/rcm.9895","DOIUrl":"https://doi.org/10.1002/rcm.9895","url":null,"abstract":"<p><strong>Rationale: </strong>Surface-assisted laser desorption/ionization (SALDI) mass spectrometry (MS) builds on the use of nanostructured surfaces (e.g., coatings of colloidal nanoparticles) to promote analyte desorption and ionization. The SALDI process is believed to occur mainly through thermal processes, resulting from heating of the nanosubstrate upon absorption of the photon energy, and by assisting ionization steps. Mostly due to the accessibility of the respective hardware, the majority of SALDI-MS studies use standard laser wavelengths for MALDI (i.e., 337 or 355 nm), even though peak absorption of the SALDI nanosubstrate might completely differ from these values.</p><p><strong>Methods: </strong>Here, we investigated the wavelength dependence in SALDI-MS to determine if wavelength adjustment would be beneficial, and to provide new experimental data for a better understanding of the SALDI mechanism. To this end, gold nanoparticles (AuNPs) sprayed onto microscope glass slides were employed as SALDI nanosubstrates and L-arginine as a model analyte. In addition, we used 2,5-dihydroxyacetophenone (2,5-DHAP) for classical MALDI-MS using the same experimental setup. Arginine ion signals were recorded as a function of laser wavelength and laser fluence. Mass spectra were acquired in the wavelength range between 310 and 630 nm, including the absorption maximum of the sprayed AuNPs around 550 nm and that of 2,5-DHAP around 380 nm.</p><p><strong>Results: </strong>Laser fluence thresholds for the generation of arginine ions were found to be dependent on the laser wavelength and to inversely correlate with the absorbance profiles of the deposited AuNPs and 2,5-DHAP, respectively. Very differently to MALDI, in SALDI ionization efficiency was found to strictly linearly decrease with increasing laser wavelength.</p><p><strong>Conclusions: </strong>Our results, therefore, corroborate the general assumption that material ejection in SALDI-MS is mainly driven by thermal processes in the low laser fluence range and add new evidence that the ionization process is directly influenced by photon energy when AuNPs are employed as nanosubstrates.</p>","PeriodicalId":225,"journal":{"name":"Rapid Communications in Mass Spectrometry","volume":" ","pages":"e9895"},"PeriodicalIF":1.8,"publicationDate":"2024-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142102727","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Integration of high-resolution mass spectrometry technology with molecular network analysis and systems biology techniques to elucidate the active ingredients and mechanisms of Shiduqing capsules","authors":"Zhiyan Liu,&nbsp;Shuang Li,&nbsp;Lei Wang,&nbsp;Wei Zhang,&nbsp;Yuanyuan Cao,&nbsp;Chun Bao,&nbsp;Chenning Zhang","doi":"10.1002/rcm.9903","DOIUrl":"10.1002/rcm.9903","url":null,"abstract":"<div>\u0000 \u0000 <section>\u0000 \u0000 <h3> Rationale</h3>\u0000 \u0000 <p>Shiduqing Capsules, a well-known Chinese patent medicine, are widely used clinically for the treatment of pruritus. However, to date, there is a lack of research on its pharmacological substances and mechanisms of action.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>In the current study, the chemical components of Shiduqing Capsules were identified using UHPLC-QE-Orbitrap-MS technology. Molecular network analysis was employed to identify structurally similar compounds to the known chemical components. The potential molecular targets of the active ingredients were predicted using the SwissTargetPrediction website. The identified targets were further analyzed using gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis through the DAVID database. Molecular docking was used to validate the network pharmacology results.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>Ultimately, A total of 51 chemical components of Shiduqing Capsules were identified. Molecular network analysis identified 21 flavonoids and 13 terpenoids. The core targets of these ingredients include TP53, AKT1, and STAT3. GO and KEGG enrichment analysis revealed 1,371 different biological functions and 177 signaling pathways. Molecular docking confirmed the high affinity between multiple core active ingredients of Shiduqing Capsules and pruritus targets.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusion</h3>\u0000 \u0000 <p>In conclusion, the effective ingredients of Shiduqing Capsules exert a multifaceted therapeutic effect on pruritus through multiple targets and pathways.</p>\u0000 </section>\u0000 </div>","PeriodicalId":225,"journal":{"name":"Rapid Communications in Mass Spectrometry","volume":"38 21","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142091255","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Thermodynamics of gaseous strontium and calcium cerates studied by Knudsen effusion mass spectrometry and estimation of relative electron ionization cross-section for CeO2(g)","authors":"Sergey M. Shugurov,&nbsp;Sergey I. Lopatin,&nbsp;Olga A. Zhinkina,&nbsp;Andrej I. Panin,&nbsp;Natalia S. Panina","doi":"10.1002/rcm.9894","DOIUrl":"10.1002/rcm.9894","url":null,"abstract":"<div>\u0000 \u0000 <section>\u0000 \u0000 <h3> Rationale</h3>\u0000 \u0000 <p>Ceria-based systems are of great interest because of their unique properties. Such systems may be used as anode materials for SOFCs or in oxygen sensors. The exploitation of these materials often requires high temperatures. In such conditions, the partial or complete evaporation of materials is possible. Therefore, knowledge of the values of partial pressures and thermodynamic properties is essential to predict and/or prevent possible consequences and accidents.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>Knudsen effusion mass spectrometry was used to determine partial pressures of vapor species over the SrO–CeO₂ and CaO-CeO₂ systems. Measurements of partial pressures were performed with a MS-1301 mass spectrometer. Vaporization was carried out using molybdenum or tungsten effusion cells. A theoretical study of gaseous strontium and calcium cerates was performed by several quantum chemical methods: density functional theory (DFT) M06, DFT PBE0, and MP2.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>The minimum value of relative electron ionization cross-section for CeO₂ was estimated. In the temperature range of 2218–2249 K above the SrO-CeO₂ system and of 2128–2208 K above the CaO-CeO₂ system, gaseous M, MO, MO, CeO₂, O, O₂ and MCeO₃ (M = Sr, Ca) were found. Energetically favorable structures of gaseous SrCeO₃ and CaCeO₃ were found, and vibrational frequencies were evaluated in the “rigid rotor-harmonic oscillator” approximation. On the basis of the equilibrium constants of gaseous reaction MO + CeO₂ = MCeO₃, the standard formation enthalpy of gaseous SrCeO₃ (−913 ± 26 kJ/mol) and of gaseous CaCeO₃ (−917 ± 26 kJ/mol) at 298 K were determined.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>The estimated value of relative electron ionization cross-section for CeO₂ is in agreement with the general rule applicable for dioxides. The stability of SrCeO₃ and CaCeO₃ gaseous species was confirmed by KEMS. Gas-phase reactions involving gaseous SrO (CaO) and CeO₂ with gaseous SrCeO₃(CaCeO₃) were studied. Enthalpy of formation reaction of gaseous SrCeO₃(CaCeO₃) from gaseous SrO (CaO) were evaluated theoretically, and the obtained value is in agreement with the experimental one.</p>\u0000 </section>\u0000 </div>","PeriodicalId":225,"journal":{"name":"Rapid Communications in Mass Spectrometry","volume":"38 21","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142091256","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Trapped and drift-tube ion-mobility spectrometry for the analysis of environmental contaminants: Comparability of collision cross-section values and resolving power","authors":"Lidia Belova,&nbsp;Noelia Caballero-Casero,&nbsp;Ana Ballesteros,&nbsp;Giulia Poma,&nbsp;Alexander L. N. van Nuijs,&nbsp;Adrian Covaci","doi":"10.1002/rcm.9901","DOIUrl":"10.1002/rcm.9901","url":null,"abstract":"<div>\u0000 \u0000 <section>\u0000 \u0000 <h3> Rationale</h3>\u0000 \u0000 <p>Ion-mobility (IM)–derived collision cross-section (CCS) values can serve as a valuable additional identification parameter within suspect and non-target screening studies of environmental contaminants. However, these applications require to assess the reproducibility of CCS calculations between different IM set-ups. Especially for the comparison of trapped and drift-tube IM (TIMS/DTIM) derived CCS values, data for environmental applications is lacking.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>The presented study assessed the bias of TIMS derived CCS_N2 (^TIMSCCS_N2) values of 48 environmental contaminants from three classes in comparison to a previously established DTIM database. Based on two sets of isomeric bisphenols, the resolving power of both systems was compared, addressing the instrumental settings which influence the resolution of TIMS measurements.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>For 91% of the datapoints, bias between ^TIMSCCS_N2 and ^DTCCS_N2 values (latter set as reference) were &lt; 2%, indicating a good inter-platform reproducibility. TIMS resolving power was dependent on the selected mobility window and ramping times whereby a resolution of up to 116 was achieved. Similar resolving power was observed for multiplexed DTIMS data if a high-resolution post-processing step was implemented.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>These results provide valuable insights in CCS_N2 reproducibility facilitating database transfer in future TIMS based studies. Knowledge on the influence of acquisition settings on robustness of ^TIMSCCS_N2 calculations and resolving power can ease method development supporting efficient development and reliable identifications of emerging environmental contaminants.</p>\u0000 </section>\u0000 </div>","PeriodicalId":225,"journal":{"name":"Rapid Communications in Mass Spectrometry","volume":"38 21","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142091257","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Identification, characterization, and in silico ADMET prediction of nirmatrelvir and its degradation products using HPLC-PDA and LC-QTOF-MS/MS","authors":"Matta Ashwin Kumar,&nbsp;Raja Sundararajan","doi":"10.1002/rcm.9896","DOIUrl":"10.1002/rcm.9896","url":null,"abstract":"<div>\u0000 \u0000 <section>\u0000 \u0000 <h3> Rationale</h3>\u0000 \u0000 <p>Nirmatrelvir is a protease inhibitor that is essential for virus replication. Nirmatrelvir is indicated for the management of mild to severe cases of COVID-19 in individuals who are 12 years of age or older. Forced degradation studies of nirmatrelvir were carried out on the drug substance in solid and solution forms, subjecting it to various stress conditions according to International Conference on Harmonisation (ICH) Q1A(R2) and Q1B guidelines. The analytical method was validated as per the ICH Q2(R1) guidelines.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>The drug substance (nirmatrelvir) was subjected to hydrolysis (acidic, alkaline, and neutral), thermal, photolytic, and oxidative stress conditions. Five degradation products (DPs) of nirmatrelvir formed under hydrolytic (acidic and alkaline) and oxidative (2,2-azobisisobutyronitrile) stress conditions. These degradation products were identified and separated using reverse-phase HPLC on a phenomenex kinetex C8 column (250 mm × 4.6 mm × 5 μm) with gradient elution. The mobile phase consisted of 0.1% formic acid and acetonitrile, and detection was carried out at a wavelength of 210 nm.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results and conclusions</h3>\u0000 \u0000 <p>Nirmatrelvir and its five DPs were efficiently separated using reverse phase–HPLC. These five DPs were identified and characterized using LC-electrospray ionization (ESI)-Q-TOF-coupled mass spectrometry analysis in the ESI-positive ionization mode. The formation mechanisms of the DPs and the most probable mass fragmentation pathways for both nirmatrelvir and its DPs were elucidated. The developed method demonstrated selectivity, accuracy, linearity, and reproducibility, making it appropriate for quality control of nirmatrelvir and future research studies. Additionally, the physicochemical and Absorption, Distribution, Metabolism, Excretion, and Toxicity (ADMET) properties of nirmatrelvir and its DPs were predicted using ADMET predictor software. The toxicity profile revealed that DP2 and DP3 have teratogenic effects while DP1 and DP3 caused phospholipidosis.</p>\u0000 </section>\u0000 </div>","PeriodicalId":225,"journal":{"name":"Rapid Communications in Mass Spectrometry","volume":"38 20","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/rcm.9896","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142054342","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}