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Microplastics (MPs) in the air are one of the major concerns due to their possible health risks. In addition, airborne microplastics act as a carrier for several toxic air pollutants and cause carcinogenic, mutagenic and teratogenic effects. Nylon 66 is one of the most abundant MPs in the microenvironments. In this study, we report an optimized method for the quantification of nylon 66 MPs present in the fine particulate matter (PM2.5) using high-performance liquid chromatography coupled to tandem mass spectrometry (HPLC-MS/MS). The optimized method exhibited excellent linearity, recovery rates, intraday and interday precision and sensitivity. The optimized method was deployed to carry out a pilot study to measure the mass concentrations of nylon 66 microplastics present in the inhalable fraction of particulate matter collected in a shopping complex. The observed mass concentrations of nylon 66 MPs in this study are in the range from 0.30 ng m−3 to 4.37 ng m−3. This study demonstrates the presence of inhalable fraction of nylon 66 MPs in the indoor environment and their mass concentrations were determined using HPLC-MS/MS. [ABSTRACT FROM AUTHOR]

AbstractA method for the determination of eight benzenes (BTEXs) and twelve chlorobenzenes (CBs) in goat’s milk by headspace solid-phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS/MS) was developed. The study investigated the impact of various factors such as extraction fiber type, salt amount, equilibrium conditions, and desorption conditions on the outcomes. Target analytes were separated on a DB-HeavyWAX column and quantified using the external standard method. The results showed that the target compounds had a good linear relationship in the range of 0.01 ∼ 50 μg/L (R2 > 0.997), the limit of detection (LOD) was 0.003 ∼ 0.150 μg/L, and the limit of quantification (LOQ) was 0.01 ∼ 0.50 μg/L. The average recoveries were 82%–116% and the relative standard deviation (RSD) was 0.8%–17.3% under the three addition levels of 1×, 2×, and 10 × LOQ. In a survey of twenty goat’s milk samples, only ethylbenzene, xylenes, cumene, chlorobenzene, and 1,4-dichlorobenzene were detected at levels exceeding their respective limits of quantification. The method was evaluated using two ecological scales (Eco-Scale), GAPI and AGREEN, to verify its environmental friendliness and applicability. This method is simple, green, and efficient, which provides a certain theoretical basis for the production and quality safety evaluation of dairy products. [ABSTRACT FROM AUTHOR]

Objective: NeoBase 2 Non-derivatized MSMS assay kit (NeoBase 2 kit) was used for newborn screening, the performance of the NeoBase 2 kit should be validated before its implementation in clinical diagnostic laboratories. Methods: Leftover dried blood spot samples, quality control materials in the NeoBase 2 kit, and proficiency testing materials received from the NSQAP were used. Precision, accuracy, LOD, LLOQ, recovery, and stability were carried out to verify the performance of the Waters ACQUITY TQD MS/MS system with the NeoBase 2 kit for newborn screening. Cutoffs were determined and analytes requiring different cutoffs in preterm neonates were investigated. Results: Within-run and between-run precisions ranged from 3.95% to 14.41%. The accuracy and stability were within 15%. All analytes demonstrated acceptable LOD, LLOQ, and recoveries. Cutoffs for term and preterm neonates were established. Conclusions: The performance of the NeoBase 2 kit is acceptable and can be implemented in clinical diagnostic laboratories. [ABSTRACT FROM AUTHOR]

Anthocyanins (ANCs), a kind of natural pigments, are widely present in food substrates. Evidence has shown that ANCs can promote health in terms of anti-oxidation, anti-tumor, and anti-inflammation. However, the oxidative stability of ANCs limits accurate quantitation and analysis. Therefore, faster, more accurate, and highly sensitive extraction and determination methods are necessary for understanding the role of ANCs in medicine and food. This review presents an updated overview of pretreatment and detection techniques for ANCs in various food substrates since 2015. Liquid-liquid extraction and various green solvent extraction methods, such as accelerated solvents extraction, deep eutectic solvents extraction, ionic liquids extraction, and supercritical fluid extraction, are commonly used pretreatment methods for extraction and purification of ANCs. Liquid chromatography coupled with different detectors (tandem mass spectrometry and UV detectors) and spectrophotometry methods are some of the determination methods for ANC. This study has updated, compared, and discussed different pretreatment and analysis methods. Moreover, the advanced methods and development prospects in this field are comprehensively summarized, which can provide references for further utilization of ANCs. [ABSTRACT FROM AUTHOR]

We established an efficient analytical approach for simultaneous determination of benthiavalicarb-isopropyl and its four metabolites (KIF-230-M1, KIF-230-M3, KIF-230-M4, and KIF-230-M5) in fruits and vegetables. Samples were extracted with acidified acetonitrile, with octadecylsilane and graphitised carbon black as sorbent for clean-up, and UHPLC-MS/MS for determination. The approach was determined at spikes of 5, 50, and 500 μg kg−1. The recoveries of the six matrices analyzed ranged from 74.5% to 115.6% with 0.5–12.6% for intra-day RSDr (n = 5), and 0.4–13.8% for inter-day RSDR (n = 15). The five analytes in all matrices achieved high linearity (R2 > 0.9917). The limit of quantification (LOQ) of benthiavalicarb-isopropyl as well as its four metabolites in all matrices was 5 μg kg−1. This analytical approach allows for monitoring residues of benthiavalicarb-isopropyl and its metabolites in vegetables and fruits. [ABSTRACT FROM AUTHOR]

Macroautophagy/autophagy is essential for the degradation and recycling of cytoplasmic materials. The initiation of this process is determined by phosphatidylinositol-3-kinase (PtdIns3K) complex, which is regulated by factor BECN1 (beclin 1). UFMylation is a novel ubiquitin-like modification that has been demonstrated to modulate several cellular activities. However, the role of UFMylation in regulating autophagy has not been fully elucidated. Here, we found that VCP/p97 is UFMylated on K109 by the E3 UFL1 (UFM1 specific ligase 1) and this modification promotes BECN1 stabilization and assembly of the PtdIns3K complex, suggesting a role for VCP/p97 UFMylation in autophagy initiation. Mechanistically, VCP/p97 UFMylation stabilizes BECN1 through ATXN3 (ataxin 3)-mediated deubiquitination. As a key component of the PtdIns3K complex, stabilized BECN1 facilitates assembly of this complex. Re-expression of VCP/p97, but not the UFMylation-defective mutant, rescued the VCP/p97 depletion-induced increase in MAP1LC3B/LC3B protein expression. We also showed that several pathogenic VCP/p97 mutations identified in a variety of neurological disorders and cancers were associated with reduced UFMylation, thus implicating VCP/p97 UFMylation as a potential therapeutic target for these diseases. Abbreviation: ATG14:autophagy related 14; Baf A1:bafilomycin A1;CMT2Y: Charcot-Marie-Toothdisease, axonal, 2Y; CYB5R3: cytochromeb5 reductase 3; DDRGK1: DDRGK domain containing 1; DMEM:Dulbecco'smodified Eagle's medium;ER:endoplasmic reticulum; FBS:fetalbovine serum;FTDALS6:frontotemporaldementia and/or amyotrophic lateral sclerosis 6; IBMPFD1:inclusion bodymyopathy with early-onset Paget disease with or withoutfrontotemporal dementia 1; LC-MS/MS:liquid chromatography tandem mass spectrometry; MAP1LC3B/LC3B:microtubule associated protein 1 light chain 3 beta; MS: massspectrometry; NPLOC4: NPL4 homolog, ubiquitin recognition factor;PIK3C3: phosphatidylinositol 3-kinase catalytic subunit type 3;PIK3R4: phosphoinositide-3-kinase regulatory subunit 4; PtdIns3K:phosphatidylinositol 3-kinase; RPL26: ribosomal protein L26; RPN1:ribophorin I; SQSTM1/p62: sequestosome 1; UBA5: ubiquitin likemodifier activating enzyme 5; UFC1: ubiquitin-fold modifierconjugating enzyme 1; UFD1: ubiquitin recognition factor in ERassociated degradation 1; UFL1: UFM1 specific ligase 1; UFM1:ubiquitin fold modifier 1; UFSP2: UFM1 specific peptidase 2; UVRAG:UV radiation resistance associated; VCP/p97: valosin containingprotein; WT: wild-type [ABSTRACT FROM AUTHOR]

This study established a simple, rapid, and sensitive ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method for the simultaneous quantification of contezolid and its major metabolite M2 in human plasma and cerebrospinal fluid (CSF). We used isotope-labeled internal standards (IS) along with protein precipitation to efficiently eliminate impurities. The ion transition was m/z 409.1 → 269.1 for contezolid, m/z 414.1 → 269.0 for contezolid-d5, m/z 445.1 → 385.1 for M2, and m/z 450.2 → 390.1 for M2-d5. The flow rate was 0.4 mL/min with a run time of 2.5 min. Validation results demonstrated that the calibration range was 10–5000 ng/mL for contezolid, and 5–2500 ng/mL for M2 in plasma and CSF. Both analytes exhibit excellent linear relationships (all R2 ≥ 0.99). Intra- and inter-batch accuracy and precision for all quality control (QC) levels were within ± 15%, including the lower limit of quantification (LLOQ). The recoveries of contezolid and M2 were 92.60–100.4% and 92.26–99.61% in plasma and 93.33–99.19% and 91.31–98.21% in CSF, respectively. The matrix effects for contezolid and M2 were 97.20–110.3% and 98.27–105.47% in plasma and 105.25–112.99% and 103.35–109.84% in CSF, respectively. The coefficients of variation (CV%) were ≤ 12.58%. Conteozolid and M2 remained stable in plasma and CSF. This study has established a simple and accurate method for determining contezolid and M2 in human plasma and CSF, making it a valuable tool for monitoring the efficacy of central nervous system (CNS) drugs. [ABSTRACT FROM AUTHOR]

Coumarin and furocoumarins characterization in cosmetics plays an important role in protecting consumer health. The analytical technique mostly employed for the analysis of these molecules is certainly liquid chromatography coupled to photodiode array or mass spectrometer detectors. The aim of this article was to investigate on the oxygen heterocyclic compounds content in fifty hydro alcoholic fragrances using a fast, sensitive and eco-friendly liquid chromatography coupled to a triple quadrupole mass spectrometer detector analytical method without any sample pre-treatment. To the best of the author’s knowledge, this is the first research article on the quantification of thirty-six oxygen heterocyclic compounds in hydro alcoholic fragrances in less than 4 min and with the use of water/ethanol as mobile phase. Thanks to the good performance of the analytical method used, this can be proposed among the routine methods for the quality control of cosmetics and finished products. [ABSTRACT FROM AUTHOR]

A method for determining human epidermal growth factor (hEGF) in cosmetics was developed using solid-phase extraction with high-performance liquid chromatography – tandem mass spectrometry. The sample was extracted and purified by a mixed anionic solid-phase extraction column (MAX), and the eluent was passed through a nylon filter membrane into a polypropylene vial. The matrix-matched external standard method was used to quantify the analyte in multi-reaction monitoring mode. The analyte had an excellent peak shape within 11 min with a linear range from 5 to 80 ng/mL and a linear correlation coefficient (r) of 0.9995. The limit of detection and limit of quantification were 0.75 and 2.5 μg/kg, respectively. The recovery of the target was from 81.5% to 88.8%, and the relative standard deviation was between 1.16% and 5.07%. The results met the International Organization for Standardization 12787 standard. The established method was successfully applied to 30 cosmetic samples. The proposed method is sensitive, accurate, reliable, and suitable for the quantitative confirmation of hEGF and monitoring its illegal addition to cosmetics. [ABSTRACT FROM AUTHOR]

Polygonum Amplexicaule Radix is a traditional Chinese medicine for promoting blood circulation and removing blood stasis, which is often used to treat thrombotic diseases. However, its potential anticoagulant active ingredients have been unexplored. In this study, a method for rapid screening of anticoagulant active ingredients from P. amplexicaule by affinity-ultrafiltration (AUF) and high-performance – tandem mass spectrometry (HPLC-MS/MS) was established, which using thrombin as an affinity receptor target. 5 potential anti-thrombin active components were screened: gallic acid, procyanidin B2-3''O-gallate, 11-O-galloylbergenin, (-)-epicatechin gallate and di-galloyl-O-bergenin by AUF and HPLC-MS/MS. The inhibitory ability of these active ingredients to thrombin was confirmed by in vitro activity experiments and molecular docking, hence justifying that P. amplexicaule is a traditional Chinese medicine with excellent anticoagulation effects. Meanwhile, it has been shown that AUF-MS could be a way rapid screening for active substances. [ABSTRACT FROM AUTHOR]

A simple method for the determination of 19 types of phthalate acid ester plasticizers in raw textile solid waste has been developed by employing ultrasonic extraction coupled with gas chromatography – tandem mass spectrometry (GC-MS/MS). The evaluation of the plasticizers in several textile solid wastes showed that the levels were high, especially dimethylglycol phthalate. The extraction solvent, ultrasonic time, and ultrasonic temperature were optimized. Hexane was adopted as the extraction solvent, and ultrasonic extraction was performed at 20 °C for 30 min. A linear relationship from 0.02 to 1000 ng/mL was obtained with correlation coefficients(r) greater than 0.996. The limits of quantitation were from 0.08 to 30.70 µg/L based upon a signal-to-noise ratio (S/N) of 10. The recoveries were from 90.1% to 108.9% and the relative standard deviation between 0.78% and 9.43%. The method can be used for rapid screening and quantitative analysis of textile solid waste due to the simple, sensitive, and accurate assay. [ABSTRACT FROM AUTHOR]

Accurate measurement of endogenous steroid hormones in serum is a powerful tool for understanding the status of human adrenal diseases. Isotope dilution–liquid chromatography–tandem mass spectrometry is the most commonly used method for determination of steroids in serum. In this study, we used a laboratory-constructed quadrupole-linear ion trap (Q-LIT) tandem mass spectrometer to develop a new method for the quantification of five steroid hormones in serum. A simple and efficient pretreatment was improved, wherein the serum was extracted once by a mixed solvent of 1.0 mL of ethyl acetate and n-hexane. Using the optimized method, the regression coefficients of the calibration curves were all higher than 0.99, the limits of detection were from 0.31 to 1.25 ng mL−1, and the limits of quantification were between 1.00 and 2.50 ng mL−1. The intra-day (n = 3) relative standard deviations ranged from 4.24% to 13.79%, and the inter-day (n = 3) relative standard deviations from 3.99% to 11.43%. After internal standard correction, the relative recoveries of all steroids were from 86.08% to 106.60%. Twenty-two serum samples were analyzed by Q-LIT, which was compared with commercial triple quadrupole mass spectrometer. The results of the instruments had high consistency. Therefore, Q-LIT accurately quantified steroid hormones in human samples and may be used for clinical diagnosis and monitoring of hormone-dependent diseases. [ABSTRACT FROM AUTHOR]

Herbicide residue levels were analyzed in agricultural soils of Batak plain and health risk assessments were made for relevant pesticides. Herbicide contamination levels were analyzed with the use of Quick-Easy-Cheap-Efficient-Rugged-Safe (QuEChERS)-liquid chromatography/tandem mass spectrometry (LC–MS/MS) procedure. Herbicide-free soil samples were spiked at two different levels. Overall recovery of the method was 87.32%. Present findings were parallel to SANTE recovery limits. About 50% of collected samples from the study sites contained herbicides at different concentrations. Totally, eight herbicides were detected, and herbicide concentrations ranged between 1.085 and 1724.23 μg kg−1. Metolachlor had the highest concentration (1724.23 μg kg−1) in a sample taken close to the pesticide waste disposal area. Six herbicides were detected at different concentrations in the same sample. Persistent herbicides (terbuthylazine and pendimethalin) were detected in 35 samples. Risk assessments revealed that hazard index (HI) and hazard quotient (HQ) were less than 1. The greatest HQ values were identified for terbuthylazine as 2772.48 × 10−7 and 20793.61 × 10−7 for adults and children, respectively. The HI for all herbicides were 3916.05 × 10−7 for adult and 29370.39 × 10−7 for children. [ABSTRACT FROM AUTHOR]

Per- and polyfluoroalkyl substances (PFAS) analysis has become crucial due to their presence in the environment, their persistence and potential health risks. These compounds are commonly used in food contact materials (FCM) as a coating to provide water and grease-repellent properties. One of the pathways for PFAS to enter the human body is either through direct consumption of contaminated food or indirectly through migration from FCM into food. The purpose of this study was to investigate where the initial contamination of paper FCM occurs. We analysed paper material consisting of fresh fibre and secondary materials, intended to produce food packaging for the presence of PFAS. The samples were extracted and analysed for 23 different PFAS substances using the targeted approach with LC tandem mass spectrometry (LC-MS/MS). This analytical technique detects specific, easily ionisable PFAS with high sensitivity. However, one drawback of this approach is that it allows the identification of less than 1% of the PFAS known today. For this reason, we used combustion ion chromatography (CIC) to determine the content of extractable organic fluorine compounds (EOF) and compare it to the total fluorine content. The targeted analysis using LC-MS/MS measured an average sum concentration of PFAS of 0.17 ng g−1 sample. Our research shows that the primary PFAS contamination happens during the recycling process since all of the samples in which the targeted PFAS were measured belonged to the secondary material. The most frequently detected analytes were PFOA and PFOS, detected in 90% and 62% of the samples, respectively, followed by PFBS (in 29% of the samples). CIC showed that measured PFAS via LC-MS/MS amount to an average of 2.7 × 10−4% of total fluorine content, whereas the EOF was under the LOD in all of the measured samples. This result highlights the complexity of the accurate determination of PFAS compounds, displaying what kind of information the chosen methods provide. [ABSTRACT FROM AUTHOR]

To investigate cannabinoid content and profiles, 16 cannabinoids were quantified in 30 commercial hemp seed edible oils. In addition, one hemp seed oil was subjected to thermal processing up to 200 °C for up to 60 min. UHPLC-MS/MS was used for analysis. The content of cannabinoids in the samples ranged from 9 to 279 mg kg−1 (sum) and for Δ9-tetrahydrocannabinol (Δ9-THC) from 0.2 to 6.7 mg kg−1. Three samples exceeded the EU Δ9-THC equivalent maximum levels of 7.5 mg kg−1 for hemp seed oils. Cannabinoid profiles can provide indications of different product characteristics (e.g. degree of processing, variety of plant material). Furthermore, intense thermal processing (200 °C, 60 min) led to 38% decrease in sum cannabinoid content (sum of all analysed cannabinoids in this study), 99% decrease in cannabinoid acids, and 22% increase in Δ9-THC. [ABSTRACT FROM AUTHOR]

A novel post-synthetic modification of magnetite@MIL-53(Fe)-NH2 core-shell nanocomposite was performed to extract ultra-trace amounts of Pd(II) ions from the real samples. To explore and optimise the effect of parameters on the preconcentration design of the experiment was employed. The highest removal efficiency in the adsorption step was obtained using the following condition: pH of sample, 6.5; adsorption time, 3.8 min; magnetite@MIL-53(Fe)-NH-PITC NPs amount, 20 mg. The highest extraction recovery (%) was achieved using 0.8 mL of 0.85 mol L−1 HCl as the desorbing solution; and by applying an elution time of 3.5 min. Afterwards, to study the equilibrium data, various adsorption isotherm models were explored. The data showed that the Langmuir model describes the adsorption process better than the other models. Eventually, the maximum adsorption capacity and model constant equal to 100 mg g−1 and 0.11 L mg−1, were obtained, respectively. Besides, the kinetic data were well fitted to the pseudo-second-order based on the highest correlation coefficient that was achieved. The limit of detection, the limit of quantification, and the linear range of the proposed method were 0.05 μg L−1, 0.2 μg L−1, and 0.2–100 μg L−1 (r2 = 0.9936), respectively. The precision was explored as relative standard deviation value at three concentration of 0.5, 10, 75 ng mL−1 (n = 3) that was 12.5%, 9.3% and 6.6%, respectively. Ultimately, the new magnetic adsorbent could be employed for extraction/quantification of ultra-trace amounts of Pd(II) ions in real samples and the relative recovery values were obtained in the range of 88–102%. [ABSTRACT FROM AUTHOR]

A simple, rapid and sensitive method for the determination of aflatoxins in peanut oil was developed using MIL-101(Cr) material filled syringe filter for one-step solid-phase extraction (SPE) with high-performance liquid chromatography—tandem mass spectrometry (HPLC-MS/MS) detection. The MIL-101(Cr) sorbent was characterized and its mass, the loading solution, and the eluent were optimized; under these conditions, a matrix matching internal standard method was developed. The linear range was from 0.1 to 20 ng/mL with correlation coefficient (r) exceeding 0.9998. The recoveries were between 94.7% and 105.9% with relative standard deviations from 2.02% 6.88%. The recoveries of inter-day and intra-day measurements were from 93.0% to 98.5% and 97.6% to 100.7%. The precision values for inter-day and intra-day analyses were from 6.09% to 7.68% and 2.56% to 4.30%, respectively. The pretreatment efficiency of the developed method was superior to literature procedures and used to determine aflatoxins in 126 peanut oil samples from local markets. 38 samples had positive results and 1 sample exceeded the allowable limit. Hence, the developed protocol was suitable for the determination of aflatoxins in peanut oil. [ABSTRACT FROM AUTHOR]

This document titled "(Self) Assembled news: recent highlights from the supramolecular chemistry literature (quarter 3, 2024)" provides a summary of recent advancements in the field of supramolecular chemistry. The first highlight discusses the development of a supramolecular system that functions as a molecular ion pump, converting light energy into work and pumping KCl across a hydrophobic barrier against the concentration gradient. The second highlight focuses on the development of a supramolecular gel that can trap, protect, and release sensitive proteins without the need for additional excipients and cold-chain management. The third highlight explores the use of classical supramolecular binding events to improve the reliability of decoding synthetic digital polymers. The document also briefly mentions other advancements in the field, such as the development of multiply-switchable foldamers and the use of supramolecular guest binding in electrocatalytic reactions. [Extracted from the article]

A 30 year old man was found with no signs of life in front of the house. The cyanide concentration in blood and urine was determined five years after the man's death. What is more, a stability study was conducted for 730 days in an authentic casework blood sample. Sample preparation procedure included precipitation with methanol:water mixture, solid phase extraction (SPE) and derivatization with the use of PFB-Br (pentafluorobenzyl bromide). The sample was analyzed using GC-QqQ-MS/MS (gas chromatopraphy coupled with tandem mass spectrometry) isotope dilution method. Separation was done using a SH-RXI-5MS column (30 m x 0.25 mm, 0.25 µm). Detection of PFB-CN and PFB-13CN was achieved using a triple-quadrupole mass spectrometer with an electron ionization (EI) ion source in multiple reaction monitoring (MRM) mode. After 5 years from the man's death, cyanide concentration was: 1900 ng/mL in blood and 500 ng/mL in urine. Stability study performed in an authentic blood sample 6 and 7 years after the man's death revealed cyanide concentrations of 1898.2 ng/mL and 1618.7 ng/mL, respectively. While spectrophotometric and colorimetric methods recorded both decrease and increase in cyanide concentration over time, newer chromatographic methods mainly indicate a decrease. The studies presented in this paper seem to confirm this trend. However, in order to interpretate the results of cyanide concentration in biological material reliably, more research is still necessary. [ABSTRACT FROM AUTHOR]

A simple and convenient synthesis of 9-hydroxy[13C6]phenanthrene has been developed from one-ring labeled [13C6]phenanthrene in three steps, involving a copper-ethyl acetate catalyzed "Ullmann-type" reaction. The mild conditions of this nucleophilic aromatic substitution are particularly advantageous in the case of expensive labeled material. Stable-labeled 9-hydroxy[13C6]phenanthrene has proven to be an ideal [M + 6]isotopomer for use as an internal standard for quantification of OH-polycyclic aromatic hydrocarbons by gas chromatography with tandem mass spectrometry (GC-MS/MS) in human urines. [ABSTRACT FROM AUTHOR]

Polycystic ovarian syndrome (PCOS) is a commonly occurring reproductive disorder among the reproductive-aged women. Its global occurrence varies based on diagnostic guidelines, ethnicities, and locations of concern. Insulin resistance (IR) is commonly observed around 65–70% of women diagnosed with PCOS, representing a prevalent association. Consequently, the study was designed with an objective of illustrating the effect of insulin on mural and cumulus granulosa cells (GCs) of PCOS patients in comparison to normal ovulating women. This study is a case–control design, wherein a total of 80 participants were recruited meeting criterion of inclusion and exclusion, divided into 8 groups with each group consisting of 10 samples. The process involves the isolation and culturing of mural granulosa cells (MGC) and cumulus granulosa cells (CGC) with and without exposure to insulin. The proteins released by untreated GCs and insulin-treated GCs were extracted, and complex protein mixtures were digested with trypsin, followed by tandem mass spectrometry analysis and data processing using bioinformatics. We found 595 proteins in both control and PCOS samples, of which 310 were contributed by MGCs and 285 by CGCs. The PCOS MGCs expressed 20%, both the normal MGCs and CGCs have equal representation of 16% by each, whereas the PCOS CGCs proteins contributed 15% of the total of the proteomic expression. However, the poor expression observed with the Insulin exposure, the Insulin treated PCOS CGCs contributes 13%, PCOS MGCs contributes 8%. The normal MGCs upon the Insulin treatment give 8% then and there only 4% of proteins expressed by normal CGCs after Insulin treatment. The Venn analysis widened on their precise expression topographies. The examination of strings exhibited important protein–protein interaction pathways. This is a pioneering investigation aimed to establish the link between hyperinsulinemia in localized follicular GCs and PCOS mechanisms by comparing them to control group. The examination of various attributes, mechanisms, and traits shown by genes and proteins in individuals with PCOS compared to control populations, alongside the investigation of the dynamics of these genes and proteins following exposure to insulin, holds promise for the formulation of novel hypotheses and strategies in the identification of new biomarkers. [ABSTRACT FROM AUTHOR]

In humans, AMPylation of cellular proteins is carried out by Huntingtin yeast-interacting protein E (HYPE), activated under conditions of endoplasmic reticulum stress, such as in cancer cells. Extracts of the human chronic lymphocytic leukemia cell line, OSU-CLL, were fractionated using immuno-precipitation with antibodies against adenosine-phosphate and then AMP-Tyr. The proteins isolated were modified with AMP, the 'AMPylome.' AMP-labelled peptides isolated from HYPE wild-type (WT) and HYPE knock-out (KO) cells were identified using tandem mass spectrometry. A total of 213 proteins were identified from WT cell extracts, while only 23 of these were pulled down from KO cells, consistent with the presence of another AMPylator, besides HYPE. The KO cells were more sensitive to fludarabine nucleoside (2-FaraA) than WT cells. Ingenuity Pathway Analysis of the AMPylated proteins identified in WT cells clustered actin binding proteins of the cytoskeleton, and proteins of the RHO GTPase pathway that would jointly stimulate cell proliferation. [ABSTRACT FROM AUTHOR]

A rapid and simple magnetic solid phase extraction-liquid chromatography-tandem mass spectrometry method is reported to determine vancomycin in human plasma. The Fe3O4@SiO2 nanocomposite was prepared using silica nanoparticles obtained from rice husk waste and its modification using ammonia solution to obtain a Fe3O4@SiO2-NH2 nanohybrid as a new sorbent. The structure and morphology of the sorbent were characterized by X-ray diffraction, field emission scanning electron microscopy, and Fourier transform infrared spectroscopy. The nanosorbent was successfully used in magnetic solid phase extraction without hazardous solvents in 9 min with analysis by high-performance liquid chromatography – tandem mass spectrometry. Under the optimized conditions, the method provided a linear range from 10 to 1000 ng mL−1. The intra-day (n = 3) and inter-day precision (n = 3 working days) were below 10% relative standard deviation. The developed procedure was employed for determining vancomycin in human plasma with recoveries from 84.0 to 109.5% for spiked samples. [ABSTRACT FROM AUTHOR]

LN005 is a peptide–drug conjugate (PDC) targeting glucose-regulated protein 78 (GRP78) to treat several types of cancer, such as breast, colon, and prostate cancer. As a new drug modality, understanding its metabolism and elimination pathways will help us to have a whole picture of it. Currently, there are no metabolic studies on LN005; therefore, this study aimed to investigate the metabolism of LN005, clarify its metabolic profile in the liver S9s of different species, and identify the major metabolic pathways and differences between species. The incubation samples were measured by ultra-high performance liquid chromatography combined with orbitrap tandem mass spectrometry (UHPLC-Orbitrap-HRMS). The results showed that LN005 was metabolised by liver S9s, and four metabolites were identified. The main metabolic pathway of LN005 in liver S9s was oxidative deamination to ketone or hydrolysis. Similar metabolic profiles were observed in mouse, rat, dog, monkey, and human liver S9s, indicating no differences between these four animal species and humans. This study provides information for the structural modification and optimisation of LN005 and affords a reference for subsequent animal experiments and human metabolism of other PDCs. [ABSTRACT FROM AUTHOR]

Diamondoids form a molecular class of cage-like structures and serve as a link between small, cyclic hydrocarbons and bulk nanodiamonds. Comparisons have been made between the infrared spectra of diamondoids and unidentified infrared emission bands seen in the spectra of certain stars with circumstellar disks. It is also suggested that their radical cations may contribute to features in the largely unassigned diffuse interstellar bands due to their low ionisation energy and absorption in the visible range. However, the optical spectra of these cations have only recently begun to be measured experimentally, which is required for astronomical identification. Herein, we present the first optical spectrum of the 1-cyanoadamantane radical cation (C11H15N, AdaCN+) between 275 and 1200 nm. The spectrum is obtained by electronic photodissociation (EPD) of mass-selected ions generated by electron ionisation in a tandem mass spectrometer coupled to a cryogenic trap held at 5 K. Experimental results are interpreted by (time-dependent) density functional theory calculations. The dominant fragmentation channels are HCN loss at low energies and C4H6N loss at energies above 2.9 eV. The EPD spectrum reveals broad bands that are rationalised by lifetime broadening and Franck-Condon congestion arising from geometric changes upon excitation. The astrophysical implications are discussed. [ABSTRACT FROM AUTHOR]

Intramolecular radical and proton migration in the gas phase are important processes driving the dissociation reactions underlying common tandem mass spectrometry processes, such as collision-induced and electron-induced dissociation reactions (CID and ExD). Mechanistic insights in these processes requires experiments that probe the molecular structures of ions along the reaction pathways, usually combined with quantum-chemical calculations. The combination of ion trap mass spectrometry with IR laser spectroscopy, pioneered among others by Dieter Gerlich, provides a particularly effective method to explore details of the ion structures. In this work, we employ infrared multiple-photon dissociation (IRMPD) spectroscopy and density functional theory (DFT) calculations to probe the reactant and product ion structures of a homolytic bond cleavage reaction. First, we employ IRMPD spectroscopy to establish that protonation of the 4-bromoaniline precursor occurs on the amine moiety and then that C-Br homolytic cleavage produces the π-radical cation of aniline. Transition-state calculations are performed to compare the various pathways that connect reactant and product ions, including both proton and radical transfer mechanisms. [ABSTRACT FROM AUTHOR]