Today, matrix-assisted laser desorption/ionization-intact cell mass spectrometry (MALDI-ICMS) is used in clinical environments for rapid pathogen identification, referred to as MALDI biotyping. This method relies on the generation of characteristic mass spectrometric profiles of intact microorganisms. Single-celled organisms are often used for pharmaceutical production, while this allows for the production of complex products, close monitoring and control of these processes is essential. In this study, we propose the use of MALDI-ICMS as a potential at-line approach for fast monitoring of the progress of a biotechnologically relevant fermentation process employing E. coli as a host. We demonstrate the reproducibility of the method, thereby indicating its potential to predict the progress of antibody fragment production in E. coli in an industrial setting. We evaluated various aspects of sample preparation, including the choice of matrix and solvent concentration, sample loading, and sample-to-matrix ratios. Our workflow allowed monitoring of over 100 signals across a 32-h span of E. coli fermentation. To control instrumental variability, we performed eight technical replicates and achieved excellent repeatability, with 9% median relative standard deviation of peak intensities. Principal component analysis revealed strong time-related differences of the mass spectra, allowing to differentiate the data based on fermentation phases. Furthermore, to assess direct monitoring of product expression, we adapted acquisition parameters to enable product detection via MALDI-ICMS. The presented MALDI-ICMS workflow allowed reliable monitoring of cellular changes during fermentation, thereby expanding the applications of MALDI-ICMS to process analytical technologies (PAT).

Fritillaria Bulbus (FB) is a valuable traditional Chinese medicine with diverse pharmacological activities. Due to economic incentives, high-quality FBs are frequently adulterated with morphologically similar counterfeit species in commercial markets. A rapid analytical method integrating thermal-assisted plasma ionization time-of-flight mass spectrometry (TAPI-TOFMS) with chemometric algorithms was developed and validated for the botanical origin authentication and adulteration identification of FB. Featuring simple pretreatment, high throughput, rapid detection, and excellent reproducibility, the established method was systematically verified by analyzing a total of 172 FB samples. Conventional chemometric analyses (PCA, PLS-DA, OPLS-DA) achieved effective sample separation based on botanical origins and different authentic-counterfeit adulteration pairs. The constructed PLS-DA and OPLS-DA models presented satisfactory explanatory and predictive capacities with reliable statistical parameters. Furthermore, three machine learning algorithms (RF, SVM, ELM) were adopted to build identification models for authentic FBs and their adulterants. All models yielded high prediction accuracies for discriminating authentic CBs from counterfeits (> 94.0%) and for the four FB adulteration pairs (87.5%-100.0%). Among them, SVM exhibited the optimal comprehensive performance in accuracy, prediction confidence, and model stability, while all three algorithms achieved perfect identification accuracy for the QB/XJ adulteration pair. Nevertheless, the method still has limitations in low-concentration adulteration detection, with a minimum detectable adulteration level of 20%, which is mainly attributed to the non-chromatographic separation characteristic of TAPI-TOFMS and the high chemical similarity between authentic and counterfeit FB species. This rapid and robust methodology provides promising technical support for the quality supervision and authenticity identification of commercial FBs.

Screening of major cannabinoids in cannabis-derived extracts is needed when these extracts are applied in pharmacological and biological studies. Precursor ion scan-mass spectrometry (PIS-MS) is a viable approach for the detection and screening of major cannabinoids through characteristic MS/MS fragmentation behavior. A PIS-MS method was developed utilizing electrospray ionization (ESI) operated in the positive ion mode on a triple quadrupole-linear ion trap mass spectrometer (QTRAP 6500). Three cannabis extracts were screened based on established MS/MS fragmentation pattern. Characteristic product ions at m/z 193.1 and 233.1 were optimized for PIS-MS analysis. In addition, tandem mass spectrometry (MS/MS) was performed to aid in the putative identification of unknown cannabinoids, whereas authentic standards were used, when available, to confirm the identity. A quadrupole-Orbitrap (Exploris 240) mass spectrometer equipped with ESI was also utilized to provide accurate mass measurements for single-stage and MS/MS analyses, supporting the proposed structures of cannabinoids and their product ions. PIS-MS complemented with high-resolution mass spectrometry (HRMS) analysis revealed the existence of six major cannabinoids in two plant extracts, and nine in the third one. Among the detected phytocannabinoids, an unexpected cannabinoid, namely, sesquicannabigerol (Sesqui-CBG), was also identified among the most abundant ones. The MS/MS fragmentation behavior in both positive and negative ionization for Sesqui-CBG was established for the first time, supported by accurate mass measurements and second-generation MS/MS (MS[3]) experiments. In conclusion, PIS-MS provided an effective approach for the screening of abundant cannabinoids in plant products intended for therapeutic applications. MS/MS and accurate mass measurements confirmed the putative identification of detected cannabinoids. A comprehensive study for Sesqui-CBG was performed, elucidating its fragmentation pathways and product ions.

The coordination preferences of divalent metal cations toward neutral and anionic ligands were examined by positive-ion electrospray ionization (ESI) mass spectrometry, using aqueous MCl2 solutions (M = Mg, Ca, Cu, Zn) subjected to sequential ligand (L) perturbation with acetone, acetonitrile, N,N-dimethylformamide (DMF), and acetic acid. Under identical ESI conditions, Mg[2+], Ca[2+], and Cu[2+] converge toward similar ion populations dominated by charge-compensated chloride/acetate and DMF-containing adducts, indicating substantial ligand exchange during droplet desolvation and ion transfer. Zn[2+] behaves differently: It retains acetone- and acetonitrile-containing complexes and forms a broader set of mixed-ligand and polynuclear species. Quantum-chemical calculations show that acetate and DMF are the strongest ligands in the simplified M-Cl-L[+] model, but they also demonstrate that the experimental Zn[2+] selectivity cannot be reduced to maximum binding energy alone. Instead, Zn[2+] appears to occupy a favorable regime where a combination of intermediate hardness, closed-shell d[10] electronic structure is the proposed root cause of sufficient yet not irreversible ligand binding to allow coordination motifs to survive the ESI process. As much as these are proposed root-causes. The results identify Zn[2+] as an exceptional divalent cation for retaining ligand memory under ESI and define limits on the use of ESI-MS as a direct probe of solution-phase metal-ligand preferences.

Illicit drug use in social environments, such as pubs and bars, has become an increasingly significant issue for public health and safety. These venues often provide a setting where individuals may engage in recreational drug use, resulting in their residual presence on high-contact surfaces. This study aims to investigate the presence of illicit drugs in a pub within the United Kingdom, focusing on common touchpoints such as the tables, bar and men's/women's bathrooms. Over 400 surface swabs were collected across 3 weeks, with the objective of identifying traces of illicit substances commonly associated with recreational use. This study additionally explored the potential of atmospheric solids analysis probe mass spectrometry (ASAP-MS) as a screening tool for the on-site detection of cocaine, ketamine, amphetamine, diazepam and tetrahydrocannabinol (THC). Previous research has demonstrated that ASAP-MS is an effective method for detecting illicit drugs with minimal sample preparation. An untargeted screening method was developed for direct swab analysis via glass capillary rod, whereas a combined untargeted and targeted approach was used for solvent-extracted samples. For confirmatory testing, liquid chromatography mass spectrometry (LC-MS) determined the effectiveness of each ASAP-MS analysis. Results indicated that the targeted method with minimal sample preparation detected trace amounts of illicit drugs that were previously undetected using the initial screening method. However, the untargeted method, with direct sample analysis, showed potential for detecting larger quantities, particularly cocaine. Overall, the findings revealed drug residues at all touchpoints within the pub, particularly in the bathrooms which contained traces of cocaine in all samples.

Gas-phase ion spectroscopy provides direct, structure-sensitive information that complements and extends conventional mass spectrometry workflows, offering structural resolution that accurate mass and fragmentation patterns alone cannot always achieve by themselves. This review offers a practical entry point into the field by showcasing its analytical capabilities, addressed to mass spectrometrists and researchers from adjacent disciplines for whom ion spectroscopy represents an underexplored analytical resource. Four representative techniques are discussed: Electronic UV/Vis photodissociation (UVPD), infrared multiple photon dissociation spectroscopy (IRMPD), vibrational tagging photodissociation ion spectroscopy (IRPD), and helium nanodroplet isolation infrared spectroscopy (HENDI-IR). For each, the underlying physical principles are briefly introduced, and representative applications are presented with emphasis on problems of direct analytical relevance, including the structural characterization of isomeric metabolites, reactive intermediates, glycoconjugates, and drug-related compounds. Applications integrating ion spectroscopy with liquid chromatography (LC) and ion mobility spectrometry (IMS) are also discussed. The goal of this review is to convey, through carefully chosen examples, the breadth of problems that gas-phase ion spectroscopy is uniquely positioned to solve and to lower the threshold for its adoption by a wider scientific community.

Purification of crude plant extracts by solid-phase extraction (SPE) is assumed to reduce matrix effect in phytohormone quantification by LC-MS/MS, but its efficacy is rarely assessed. We used postextraction spiking of isotope-labeled phytohormones to estimate matrix effect, recovery, and processes efficiency in extracts prepared according to protocols that implement SPE with tC18 and HLB sorbents, respectively, and according to a protocol that does not include SPE. Across six structurally diverse phytohormone classes and tomato fruit and leaf matrices, we did not find significant matrix effects associated with extracts prepared with no SPE. For recovery efficiency, process efficiency, and variation, we rarely found conclusive evidence that the methods that implemented SPE were optimal relative to the one that does not. A notable exception was fruit extracts prepared using HLB sorbents, which had minimal variation for indole-3-acetic acid, trans-zeatin, and trans-zeatin riboside, all of which were detected with positive electrospray ionization.

Tungsten dichalcogenides, i.e., WX2 (X = S, Se, and Te), represent a critical class of materials with promising applications in nanoelectronics, photovoltaics, thermoelectrics, and quantum technologies. However, the performance of these dichalcogenides is often limited due to vaporization loss of chalcogens at elevated temperatures, emphasizing the necessity to understand their thermodynamic stability in operational conditions. In this study, we investigate the vaporization behavior and thermodynamic stability of WX2 compounds using a high-temperature Knudsen effusion mass spectrometer (HT-KEMS). The vapor pressures of S, Se, and Te-bearing species over WS2, WSe2, and WTe2 were derived from their respective ion intensities. By analyzing the temperature-dependent vapor pressures, the Gibbs energies of formation for WS2, WSe2, and WTe2 have been derived. Our findings provide essential insights into the thermal stability of tungsten dichalcogenides, facilitating their optimized use in high-temperature applications.

The structural analysis of biological molecules from ion mobility/mass spectrometry (IM/MS) experiments requires the comparison of measured collision cross-sections with theoretical models. The key step for this purpose is the calculation of collision cross-section for the theoretical models. Multiple methodologies have been established, including the projected superposition approximation (PSA) method. In this study, we introduce PSA-GUI, a cross-platform scientific-software implementation of the established PSA method that uses the Windows Subsystem for Linux (WSL) to enable execution on Windows systems. PSA-GUI integrates PSA parameter control, automated PDB and XYZ file handling, multimodel conformer extraction, resource-aware batch execution, and real-time job monitoring into a workflow for individual structures and conformational ensembles, thereby facilitating its use in structural-biology applications.

N,N-Dialkyl pyridin-3-yl dimethylcarbamates (carbamates) are important precursor or degradation products of CWAs, including carbamate nerve agents (CMNAs). Therefore, the detection and identification of these carbamates are essential for the verification of CWC-related chemicals. In this work, a series of ten carbamates (1-10) were comprehensively characterized by GC-EI/MS, GC-CI/MS, and CI-MS/MS. In addition, retention indices (RIs) were calculated based on the GC/EI-MS data for all carbamates (1-10) and were found to ranged from 1645.65 to 1935.45. Over all, the detailed evaluation of their fragmentation pathways, diagnostic ions, and their relative abundances enabled the identification of characteristic spectral features and facilitated the differentiation of structurally related isomeric compounds. This data set provide valuable analytical information for the verification of carbamates in environmental and related matrices, as well as during OPCW proficiency test (PTs).

Polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) are persistent environmental pollutants that bioaccumulate through the food chain, posing serious health risks to humans and animals. Dioxins and Furans are persistent, ultra-trace semi-volatile organic compounds (SVOCs) characterized by exceptionally low vapor pressures. Their quantification using chemical ionization mass spectrometry (CI-MS) and gas chromatography mass spectrometry (GC-MS) critically depends on their intrinsic physicochemical properties. In this work, density functional theory (DFT) calculations were employed to determine key molecular parameters of analytical relevance, including proton affinity, ionization energy, dipole moment, and polarizability of the 20 most important PCDDs and PCDFs. Furthermore, rate coefficients for ion-molecule reactions with the reagent ions H3O + and NO + were evaluated via classical collision models. The thermodynamic feasibility of proton- and charge-transfer pathways was systematically examined under elevated temperature and energetic conditions typical of CI-MS. In particular, the enthalpy of reaction with NO + ions was computed to confirm the viability of charge transfer mechanisms. Additionally, we present a Python-based automated utility and database of over 200 VOCs with DFT-derived descriptors for rapid estimation of reaction rate coefficients, ion kinetic energies, effective temperatures, and center-of-mass energies in CI-MS processes. (Link: https://github.com/Manjeetkb/rate-cal).

The establishment of mass spectrometry in New Zealand coincided with the transition of wartime nuclear physics into civilian research applications in geochemistry, hydrology, geothermal studies, mineral resources and environmental science. George Page (1920-1967) played a central but often overlooked role in New Zealand. Drawing on wartime and post-World War II experience in isotope separation and instrumentation, Page was directly responsible for the construction of New Zealand's first operational mass spectrometer at the Dominion Physical Laboratory. Working with Athol Rafter and Gordon Fergusson, he helped establish the technical capability that supported early radiocarbon dating, stable isotope geochemistry and hydrological studies, including the identification of the post-1954 rise in atmospheric [14]C. His work was rarely documented in publications. Instead, his contribution lay in the design and operation of the instruments that made isotope measurements possible with limited resources. This paper examines Page's role through the instruments he developed and shows how they laid the groundwork for isotope science in New Zealand.

Nicotiana glauca Graham (Solanaceae), also known as tree tobacco, naturally grows in dry, arid regions of North America, Africa, and Europe. It is recognized for both toxic and medicinal properties. This study aimed to analyze the metabolic profile of crude leaf extracts from N. glauca using liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS). A total of 16 different compounds were identified, including five alkaloids, two coumarins, two flavonoids, and two monoterpenes, as well as four hydroxycinnamic acid derivatives and one homoserine lactone. Some of these compounds were reported for the first time in N. glauca. According to the available literature, this is the first study to report the presence of puromycin in the genus Nicotiana. In addition, molecular docking studies were carried out to investigate the active site of human peroxiredoxin 5 (PDB ID: 1HD2), aiming to elucidate the potential interactions between the identified compounds and this receptor. These results suggest that N. glauca could be a good source of natural chemicals for future medical or nutritional research.

Based on previous experience and current knowledge, it is assumed that mycotoxins contaminating raw materials could be degraded or modified due to exposure to thermal and mechanical conditions during food processing, potentially resulting in degradation and/or conversion products. Nowadays, most of the information on the novel degradation products of mycotoxins is still missing; the identification and characterization of their structure and their toxicity potential is of high interest for risk assessment strategies. In the present study, the fate of aflatoxins and fumonisins during the production of gluten-free pasta made from maize flour was investigated. Gluten-free pasta was produced from both spiked dough and naturally contaminated flour, processed under pilot plant conditions that mimic the industrial conditions, resulting in a technologically feasible product. Possible degradation products of the spiked mycotoxins were identified using an untargeted stable isotope labelling liquid chromatography high-resolution mass spectrometry approach. No degradation product of aflatoxin B1 was detected above the detection limit of the experimental setup, and only one possible degradation product of fumonisin B1 or B2 at very low levels was found. The results may suggest the stability of these mycotoxins under the production conditions of gluten-free pasta.