Quadrupole Mass Spectrometer Research Articles

Development of a Water Transmission Rate (WTR) Measurement System for Implantable Barrier Coatings.

While water vapor transmission rate (WVTR) measurement is standardly used to assess material permeability, a system able to quantify liquid water transmission rate (WTR) measurement is highly desirable for implantable thin film barrier coatings. Indeed, since implantable devices are in contact or immersed in body fluids, liquid WTR was carried out to obtain a more realistic measurement of the barrier performance. Parylene is a well-established polymer which is often the material of choice for biomedical encapsulation applications due to its flexibility, biocompatibility, and attractive barrier properties. Four grades of parylene coatings were tested with a newly developed permeation measurement system based on a quadrupole mass spectrometer (QMS) detection method. Successful measurements of gas and water vapor and the water transmission rates of thin parylene films were performed and validated, comparing the results with a standardized method. In addition, the WTR results allowed for the extraction of an acceleration transmission rate factor from the vapor-to-liquid water measurement mode, which varies from 4 to 4.8 between WVTR and WTR. With a WTR of 72.5 µm g m-2 day-1, parylene C displayed the most effective barrier performance.

Cover Feature: Electrospray Ionization Tandem Mass Spectrometry With Collision Induced Dissociation of Uranyl Peroxide Nanoclusters Containing Various Uranyl Bridging Ligands (Chem. Eur. J. 39/2023)

Detecting the presence of uranyl peroxide nanoclusters (UPCs) in solution is difficult, so this study used tandem mass spectrometry with collision-induced dissociation to probe bridging ions surrounding the uranyl ion and to determine fragmentation fingerprints of UPCs. The image shows an abstract artistic representation of the nanocluster U24Pp12, [(UO2)24(O2)24(P2O7)12]48–, and its movement through a quadrupole mass analyzer with subsequent fragmentation. More information can be found in the Research Article by V. G. Rodriguez and P. C. Burns (DOI: 10.1002/chem.202300794). Image designed by V.G.R.

Determination of fluoroacetic acid in human blood and urine by accelerated solvent extraction-ion chromatography-mass spectrometry

Fluoroacetic acid is a highly polar poison used for rodent control. When ingested by the human body, it seriously damages nerve cells and heart tissues and even causes death by cardiac arrest or respiratory failure. Common detection methods for fluoroacetic acid include gas chromatography-mass spectrometry and liquid chromatography-mass spectrometry, both of which require complex pretreatment methods, such as derivatization. In this study, a method to determine fluoroacetic acid in human blood and urine based on accelerated solvent extraction-ion chromatography-mass spectrometry (ASE-IC-MS) was established. Two pretreatment methods, namely, acetonitrile precipitation and accelerated solvent extraction, were compared. Furthermore, the effects of different extraction conditions, such as the extraction time, extraction temperature, and number of cycles, were investigated. The most suitable chromatographic separation conditions, such as the chromatographic column, column temperature, and elution procedure, were determined, and the MS conditions, such as the collision energy (CE) and declustering potential (DP) of the ion pairs of the target compound, were investigated. Based on the experimental results, the optimal pretreatment methods and detection conditions were obtained, and reliable data were collected. Deionized water was used as the extraction solvent, and blood and urine samples were processed by accelerated solvent extractor. The supernatant was sequentially collected via centrifugal ultrafiltration and 0.22 μm membrane filtration, diluted 50 times, and then injected into the chromatographic column for detection. An Ion Pac AS20 IC column was used for isocratic elution with 15.0 mmol/L KOH solution as the eluent. The effluent was passed through a suppressor and into a triple quadrupole mass spectrometer, which was used to perform MS/MS (ESI-) in multiple reaction monitoring (MRM) mode. The quantitative ion was m/z 77.0>57.0 when the CE and DP were -15.0 eV and -20.0 V, respectively. An external standard method was used for quantitative analysis. The results showed a good linear relationship for fluoroacetic acid in the range of 0.5-500.0 μg/L (r>0.999), with limits of detection (LOD) and quantification (LOQ) of 0.14 and 0.47 μg/L, respectively. The recoveries of fluoroacetic acid in blood and urine were 93.4%-95.8% and 96.2%-98.4%, respectively. The intra-day RSDs for blood and urine were 0.8%-1.6% and 0.2%-1.0%, respectively, while the inter-day RSDs were 2.3%-3.8% and 3.9%-6.9%, respectively. Further investigation revealed that the matrix effects of this method in blood and urine, at -7.4% and -3.0%, respectively, were fairly weak. The established method was successfully applied to detect fluoroacetic acid in human blood and urine obtained from a poisoning case, and the results obtained provided crucial clues that led to swift case resolution. The efficiency of the method was significantly higher than that of conventional detection methods. In conclusion, the developed method has high sensitivity and good repeatability and is suitable for the rapid detection of fluoroacetic acid in human blood and urine. Moreover, because this method does not require derivatization, it is simple and efficient.

Phytochemicals from Phillyrea latifolia L. leaves and fruit extracted with various solvents: Their identification and quantification by LC-MS and antihyperglycemic effects

ABSTRACT Phillyrea latifolia L. is a type of shrubland, which is widely known as mock privet, and belongs to the Oleaceae family. The objective of this study was to compare and assess the phytochemical composition, antioxidant and antidiabetic activities of ethyl acetate, methanol and aqueous extracts of the fruit and leaves of P. latifolia L. Phenolics were analysed by detecting individual bioactive compounds using an LCMS-2020 quadrupole mass spectrometer and by calculating total phenolic content (TPC). For the first time, the antioxidant and antidiabetic activities of both leaves and fruit were determined using DPPH radical scavenging. The aqueous extract was indicated to have higher antioxidant activities than ethyl acetate and methanol extracts. The individual constituents within the different extracts for both fruit and leaves were detected as the luteolin-7-O-glucoside in the ethyl acetate (854 μg · g–1 and 1,098 μg · g–1), methanol (1,241 μg · g–1 and 2,136.43 μg · g–1) and aqueous (509 μg · g–1 and 898.23 μg · g–1) extracts, respectively. Extractions of ethyl acetate and methanol demonstrated stronger inhibitory activity against human salivary α-amylase than the aqueous extract of both parts of the mock privet. Similarly, extraction of ethyl acetate from the leaves and fruit of the mock privet indicated significantly better inhibitory activity than the methanol and aqueous extracts, respectively, for the inhibition of α-glucosidase activity. This study indicates that both fruit and leaves of mock privet may use as a potential source of natural biomolecules to promote healthy activities.

Determination of 13 halobenzoquinone disinfection by-products in drinking water using solid phase extraction-ultra performance liquid chromatography-triple quadrupole mass spectrometry

Disinfection of drinking water is critical to prevent waterborne diseases. An unexpected consequence of water disinfection is the formation of disinfection by-products by the interaction of disinfectants with organic matter (natural or anthropogenic) and halides, which present significant toxicological effects and carcinogenic risks. As an emerging disinfection by-product, halobenzoquinones (HBQs) have attracted increasing attention owing to their severe toxicity and high detection rates. The credible determination of HBQs is essential for further studies on their occurrence, toxicity, and control measures; however, HBQs are usually detected in drinking water at trace levels. Therefore, accurate and efficient analytical techniques are critical for HBQ determination and quantitation. In this study, a method based on solid phase extraction (SPE) combined with ultra performance liquid chromatography-triple quadrupole mass spectrometry (UPLC-MS/MS) was developed to determine 13 HBQs, including six chlorobenzoquinones, six bromobenzoquinones, and one iodobenzoquinone, in drinking water. One-liter water samples were added with 2.5 mL of formic acid, and 500 mL of each sample was collected for further enrichment. Pretreatment optimization mainly focused on the SPE column, washing solvent, and nitrogen blowing temperature. After extraction using Plexa SPE columns (200 mg/6 mL), the samples were washed with ultrapure water containing 0.25% formic acid combined with 30% methanol aqueous solution containing 0.25% formic acid, eluted with 6 mL of methanol containing 0.25% formic acid, and then nitrogen blown at 30 ℃. The UPLC-MS/MS parameters were optimized by comparing the results of two reversed-phase columns (BEH C18 and HSS T3) and various concentrations of formic acid in the mobile phase, as well as by establishing the best instrumental conditions. The separation of 13 HBQs was performed using an HSS T3 column (100 mm×2.1 mm, 1.8 μm) via gradient elution with a mixture of 0.1% formic acid aqueous solution and methanol as the mobile phase for 16 min. The 13 HBQs were detected using a triple quadrupole mass spectrometer equipped with a negative electrospray ionization source (ESI-) in multiple reaction monitoring (MRM) mode. Matrix-matched calibration curves were used to quantify the HBQs owing to intense matrix inhibitory effects. The results reflected the good linear relationships of the 13 HBQs and yielded correlation coefficients (r) greater than 0.999. The method detection limits (MDLs, S/N=3) were 0.2-10.0 ng/L, while the method quantification limits (MQLs, S/N=10) were 0.6-33.0 ng/L. The recoveries of the 13 HBQs were 56%-88% at three spiked levels (10, 20, 50 ng/L), and the relative standard deviations (RSDs, n=6) were less than or equal to 9.2%. The optimization method was applied to analyze HBQs in five drinking water samples. Four HBQs, namely, 2,6-dichloro-1,4-benzoquinone (2,6-DCBQ), 2,5-dibromo-1,4-benzoquinone (2,5-DBBQ), 2,6-dibromo-1,4-benzoquinone (2,6-DBBQ), and 2,6-dibromo-3,5-dimethyl-1,4-benzoquinone (2,6-DBDMBQ), were detected in the samples with detection rates of 100%, 20%, 80%, and 20%, respectively. The most frequently detected HBQ, 2,6-DCBQ, also exhibited the highest content (15.0-56.2 ng/L). The method showed high sensitivity, stability, accuracy, and efficiency, rendering it suitable for the analysis of 13 HBQs in drinking water. Compared with previous methods that mainly focused on 2,6-DCBQ and 2,6-DBBQ, the developed method achieved higher throughput and enabled the simultaneous analysis of 13 HBQs. The method presented in this study provides an opportunity to explore different types and concentrations of HBQs in drinking water, offers a deeper understanding of the occurrence of HBQs, and facilitates further studies on the health risks and control measures of these compounds.

Design and fabrication process development of MEMS quadrupole mass filter for space applications

Design and fabrication process development of MEMS quadrupole mass filter for space applications

LC-UV and LC-MS Characterization of Stress Degradation Behavior of Levocetirizine Using a Green Mobile Phase

Introduction: The current investigation's objective was to develop an HPLC method along with a validated stability-indicating method and analyzing the behavior of levocetirizine degradation under various ICH-suggested stress conditions using LC-UV and LC-MS with a triple quadrupole mass analyzer. Methods: Levocetirizine was exposed to various stressors while performing degradation studies. Using LC-UV and LC-MS methods, the degradation products formed in different stress environments were studied. The drug and degradation products were successfully separated using a Thermo Hypersil BDSC18 column having a dimension of 250 mm length, 4.6 mm internal diameter, and a particle size of 5.0 μm. The isocratic green mobile phase contained methanol:water in the proportion of 65:35 at a flow rate of 1 mL/min, and the selected wavelength for the UV detector was 230 nm. Results: Significant degradation was found in acidic, alkaline, and oxidative conditions, whereas in photo and neutral conditions, no degradation products were formed. The drug was fairly stable in the solid state. Conclusion: The values of m/z obtained from LC-MS after exposing the drug to different stress conditions were used to study fragmentation patterns, characterize the structure of the degradation product, and design the degradation pathway.

A new stability indicating HPLC and LC-APCI-MS methods for the estimation of Clofarabine in pharmaceutical dosage forms

Clofarabine is an anti-cancer drug. A new stability indicating isocratic RP-HPLC and LC-APCI-MS methods have been developed and validated for the quantification of Clofarabine as per ICH guidelines. Thermo scientific-TSQ Quantis with Vanquish HPLC coupled with MS was employed for the present study. Simpack C18 column was used for chromatographic resolution and a triple quadrupole mass spectrometer with atmospheric pressure chemical ionization (APCI) source, running in the positive mode (as well as negative mode) was used for detection. A mixture of 0.1% Formic acid: Acetonitrile was used as mobile phase on gradient mode and a mixture of Methanol: Water (50:50, v/v) was used as diluent. A wide linearity concentration range 5.0-150 μg/mL was shown by the proposed method. The proposed methods are simple, precise, and accurate are used to quantify the marketed formulations of Clofarabine. Stress degradation studies were performed and the method is found to be selective and specific.

‘Searching for a needle in a haystack;’ A Ba-tagging approach for an upgraded nEXO experiment

nEXO is a proposed experiment that will search for neutrinoless double-beta decay (0νββ) in 5-tonnes of liquid xenon (LXe), isotopically enriched in 136Xe . A technique called Ba-tagging is being developed as a potential future upgrade for nEXO to detect the 136Xe double-beta decay daughter isotope, 136Ba . An efficient Ba-tagging technique has the potential to boost nEXO’s 0νββ sensitivity by essentially suppressing non-double-beta decay background events. A conceptual approach for the extraction from the detector volume, trapping, and identification of a single Ba ion from 5 tonnes of LXe is presented, along with initial results from the commissioning of one of its subsystems, a quadrupole mass filter.

A new small thecate dinoflagellate Azadinium anteroporum sp. nov. (Amphidomataceae, Dinophyceae) isolated from the Asian Pacific

ABSTRACT The marine thecate dinoflagellate Azadinium includes species known to produce the diarrhetic shellfish toxins known as azaspiracids (AZAs). In this study, the morphology of a thecate dinoflagellate isolated from Mutsu Bay, Japan, was examined by LM and SEM, and its phylogenetic position was inferred from ITS and LSU rDNA sequences. The production of AZAs was examined by liquid chromatography-triple quadrupole mass spectrometer (LC-MS/MS). Cells were elliptical, 15.9–22.4 µm long and 11.1–17.1 µm wide. A chloroplast was positioned peripherally, with a pyrenoid near the cingulum, and the nucleus was placed in the hyposome. The hyposome was smaller than the episome, with an antapical spine on plate 2''''. Thecal tabulation was Po, cp, X, 4', 3a, 6'', 6C, 5S, 6''', 2''''. The apical pore complex consisted of a symmetrical apical pore plate (Po), a cover plate (cp) and a small canal plate (X), and was surrounded by a prominent collar formed by the apical plates. A ventral pore was located on the mid-anterior edge of plate 1' and contacted with the X-plate and/or the ventral left of plate Po. Plate 1'' was in contact with plate 1a. AZA was not detected in the cultures. Molecular phylogeny showed that the species was related to Azadinium species that possess the ventral pore on the left side of plate 1', i.e. A. cuneatum, A. dalianense, A. obesum, A. poporum, A. spinosum and A. trinitatum, but that it was not included in these species. The new species Azadinium anteroporum sp. nov. differs in the ventral pore position (mid-anterior edge of plate 1') from these related species (which have the ventral pore on the left side of plate 1'), and from A. polongum (with ventral pore on the posterior left side of 1') and all other Azadinium species (with ventral pore on the right side of 1').

Preclinical pharmacokinetics and metabolism study of SCO-267, a GPR40 full agonist, in beagle dogs using ultra-high performance liquid chromatography coupled to tandem mass spectrometry.

SCO-267 is a GPR40 full agonist that has been developed for the treatment of diabetes. To support its preclinical and clinical development, in this study, we developed an ultra-high performance liquid chromatography tandem mass spectrometric method for the determination of SCO-267 in dog plasma using cabozantinib as internal standard (IS). The chromatographic separation was obtained on a Waters acquity BEH C18 column (50×2.1 mm, I.D., 1.7 μm) and the detection was performed using Thermo TSQ triple quadrupole mass spectrometer with multiple reactions monitoring (MRM) positive mode at m/z 615.3>230.1 for SCO-267 and m/z 502.5>323.3 for IS. The method was validated over the concentration range of 1-2000 ng/mL with the lower limit of quantification of 1 ng/mL. The selectivity, linearity, precision and accuracy over this range were acceptable. The extraction recovery was more than 88.73% and no matrix effect was observed. SCO-267 was demonstrated stable during the storage and processing period. The new method was successfully applied to the pharmacokinetic study in beagle dogs following a single oral and intravenous administration. The oral bioavailability was 64.34%. In addition, the metabolites from dog liver microsomal incubation and plasma collected after an oral administration were identified by a UHPLC-HRMS method. The biotransformation pathways of SCO-267 involved oxygenation, O-demethylation, N-dealkylation and acyl glucuronidation.

Concept design of a facility to determine helium solubility in Pb-16Li

The design of an experimental setup to determine helium solubility in liquid metals, such as the eutectic Pb-16Li alloy is presented. The apparatus design is based on the concept of saturation–desorption. The lead–lithium alloy is saturated by helium through its surface as well as by bubbling the helium directly into the liquid, which also aids the liquid mixing. Once the helium saturated solution is obtained, part of the liquid is transferred into a second vessel where the dissolved helium is desorbed into a deep vacuum. The transferred portion of the liquid is weighed, and the amount of helium in the gas phase is determined from the total pressure increase as well as by residual gas analysis via a quadrupole mass spectrometer.

Progress towards the FRIB-EDM[formula omitted]-Frontend: A tool to provide radioactive molecules from isotope harvesting for fundamental symmetry studies

The under-construction FRIB-EDM3-instrument was designed to study polar radioactive molecules (such as RaF) in transparent cryogenic solids by laser spectroscopy. The instrument is divided into a frontend- and a backend section. The frontend accepts an aqueous sample from isotope harvesting and provides a mass-separated molecular ion beam in an ultra-high vacuum environment. In the backend, the ions are guided into alkali-metal vapor and the resulting neutrals are co-deposited in a solid argon matrix to perform laser spectroscopy. This work addresses the frontend of the instrument. The efficient ionization of harvested radioisotopes from aqueous samples is achieved with a spray-ionization method. Subsequently, the molecular ion beam is analyzed by mass-to-charge ratio by a quadrupole mass filter. To verify the feasibility of the approach, numerical simulations with the COMSOL and SIMION packages have been conducted. While the former was applied to study transport in ion funnels, the latter was used to investigate ion beam transmission through the lower pressure sections. Following promising simulation results, a first experimental setup is under construction.

Sustainable and Rapid Determination of Two Halogenated Pesticides in a Commercial Formulation by Solid Phase Microextraction and Liquid Phase Chemical Ionization Mass Spectrometry

This work presents a sustainable and rapid method for halogenated pesticide analysis without chromatographic separation. The system is composed of a microfluidic open interface (MOI) for solid-phase microextraction (SPME) liquid phase desorption, connected to a liquid electron ionization mass spectrometry interface (LEI-MS). Either a triple quadrupole mass spectrometer (QQQ-MS/MS, (low-resolution) or a quadrupole-time-of-flight tandem MS (QTOF-MS/MS, high-resolution) were employed, each operating in negative chemical ionization (NCI) conditions. The flow rate used (100 µL/min) to rapidly empty the MOI chamber (approximately 2.5 µL) is reduced to the working flow rate of the LEI interface (500 nL/min) by a passive flow splitter (PFS). NCI is an appropriate ionization technique for electrophilic compounds, increasing specificity and reducing background noise. Two halogenated pesticides, dicamba and tefluthrin, were extracted simultaneously from a commercial formulation matrix (CF) using a C18 fiber by direct immersion (3 min under vortex agitation). Analyte desorption occurred in static conditions inside MOI filled with acidified acetonitrile (ACN) (0.2% phosphoric acid, PA). Extraction and desorption steps were optimized to increase efficiency and accelerate the process. No chromatographic separation was involved; therefore, the system fully exploited MS/MS selectivity and HRMS accuracy demonstrating good linearity, repeatability and limits of detection (LODs) and limits of quantification (LOQs) in the pg/mL range (50 and 500 pg/mL, respectively). Low-resolution experiments showed that matrix effects (ME) did not affect the results. The fast workflow (5 min) makes the system suitable for high-throughput analysis observing the principles of green analytical chemistry (GAC).

Development of a liquid chromatography-tandem mass spectrometry (LC–MS/MS) method for characterizing pomegranate extract pharmacokinetics in humans

Pomegranate extracts standardized to punicalagins are a rich source of ellagitannins including ellagic acid (EA). Recent evidence suggests that gut microbiota-derived urolithin (Uro) metabolites of ellagitannins are pharmacologically active. Studies have evaluated the pharmacokinetics of EA, however, little is known about the disposition of urolithin metabolites (urolithin A (UA) and B (UB)). To address this gap, we developed and applied a novel ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) assay for the characterization of EA and Uro oral pharmacokinetics in humans. Subjects (10/cohort) received a single oral dose (250 or 1000 mg) of pomegranate extract (Pomella® extract) standardized to contain not less than 30 % punicalagins, < 5 % EA, and not less than 50 % polyphenols. Plasma samples, collected over 48 h, were treated with β-glucuronidase and sulfatase to permit comparison between unconjugated and conjugated forms of EA, UA and UB. EA and urolithins were separated by gradient elution (acetonitrile/water, 0.1 % formic acid) using a C18 column connected to a triple quadrupole mass spectrometer operating in the negative mode. Conjugated EA exposure was ∼5–8-fold higher than unconjugated EA for both dose groups. Conjugated UA was readily detectable beginning ∼8 h post-dosing, however, unconjugated UA was detectable in only a few subjects. Neither form of UB was detected. Together these data indicate EA is rapidly absorbed and conjugated following oral administration of Pomella® extract. Moreover, UA’s delayed appearance in the blood, primarily in the conjugated form, is consistent with gut microbiota-mediated metabolism of EA to UA, which is then rapidly converted to its conjugated form.

Determination of polychlorinated biphenyls in marine fish samples by gas chromatography tandem mass spectrometry (GC-MS/MS)

Polychlorinated biphenyls (PCBs) are a typical group of persistent organic pollutants (POPs), which have been listed under Annex A (Elimination) and Annex C (Unintentional production) of the Stockholm Convention. In this study, a gas chromatography tandem mass spectrometry method was developed and applied to analyze concentrations of 28 PCB congeners in some Vietnamese marine fish samples. PCBs in fish samples were ultrasonically extracted with an acetone/n-hexane (1/1, v/v) mixture. The extracts were cleaned up by using multilayer silica gel columns with dichloromethane/n-hexane (1/1, v/v) as elution solvent. PCBs were separated on a DB-5MS column and quantified by using a triple quadrupole mass spectrometer. The MS detector was operated in positive electron impact ionization (EI) mode and selected reaction monitoring (SRM) mode. Calibration curves of 28 PCBs exhibited good linearity (R2 &amp;ge; 0.9998). Instrument detection limits (IDLs) and method detection limits (MDLs) ranged from 0.08 to 0.023 ng/mL and from 0.07 to 1.84 ng/g, respectively. Recoveries of 28 PCBs native and 7 labeled standards in matrix-spike samples ranged from 62.3 to 88.1% and from 75.5 to 91.9%, satisfying criteria proposed by AOAC (recovery 60-115% for 10-100 ppb levels). The validated method was applied to analyze 10 marine fish samples, showing levels of &amp;sum;28PCBs from 17 to 851 (mean 230) ng/g lipid. The sum of 6in-PCBs (PCB-28; -52; -101; -138; -153; -180) based on wet weight (w/w) ranged from 1.24 to 3.15 ng/g, which is lower than the maximum level recommended by The European Union (75 ng/g (w/w). Congeners PCB-126 and PCB-169 were not detected in marine fish samples.

Plasma proteome perturbation for CMV DNAemia in kidney transplantation.

Cytomegalovirus (CMV) infection, either de novo or as reactivation after allotransplantation and chronic immunosuppression, is recognized to cause detrimental alloimmune effects, inclusive of higher susceptibility to graft rejection and substantive impact on chronic graft injury and reduced transplant survival. To obtain further insights into the evolution and pathogenesis of CMV infection in an immunocompromised host we evaluated changes in the circulating host proteome serially, before and after transplantation, and during and after CMV DNA replication (DNAemia), as measured by quantitative polymerase chain reaction (QPCR). LC-MS-based proteomics was conducted on 168 serially banked plasma samples, from 62 propensity score-matched kidney transplant recipients. Patients were stratified by CMV replication status into 31 with CMV DNAemia and 31 without CMV DNAemia. Patients had blood samples drawn at protocol times of 3- and 12-months post-transplant. Additionally, blood samples were also drawn before and 1 week and 1 month after detection of CMV DNAemia. Plasma proteins were analyzed using an LCMS 8060 triple quadrupole mass spectrometer. Further, public transcriptomic data on time matched PBMCs samples from the same patients was utilized to evaluate integrative pathways. Data analysis was conducted using R and Limma. Samples were segregated based on their proteomic profiles with respect to their CMV Dnaemia status. A subset of 17 plasma proteins was observed to predict the onset of CMV at 3 months post-transplant enriching platelet degranulation (FDR, 4.83E-06), acute inflammatory response (FDR, 0.0018), blood coagulation (FDR, 0.0018) pathways. An increase in many immune complex proteins were observed at CMV infection. Prior to DNAemia the plasma proteome showed changes in the anti-inflammatory adipokine vaspin (SERPINA12), copper binding protein ceruloplasmin (CP), complement activation (FDR = 0.03), and proteins enriched in the humoral (FDR = 0.01) and innate immune responses (FDR = 0.01). Plasma proteomic and transcriptional perturbations impacting humoral and innate immune pathways are observed during CMV infection and provide biomarkers for CMV disease prediction and resolution. Further studies to understand the clinical impact of these pathways can help in the formulation of different types and duration of anti-viral therapies for the management of CMV infection in the immunocompromised host.

An economical setup for atmospheric pressure chemical ionization drift tube ion-mobility mass spectrometry

Ion-mobility (IM) separations—performed in conjunction with mass spectrometry (MS)—increase selectivity of MS analyses. However, IM-MS instruments are costly, and many laboratories are only equipped with standard MS instruments without an IM separation stage. Therefore, it is appealing to upgrade the existing mass spectrometers with low-cost IM separation devices. Such devices can be constructed using widely available materials such as printed-circuit boards (PCBs). We demonstrate coupling of an economical PCB-based IM spectrometer (disclosed previously) with a commercial triple quadrupole (QQQ) mass spectrometer. The presented PCB-IM-QQQ-MS system incorporates an atmospheric pressure chemical ionization (APCI) source, drift tube comprising desolvation and drift regions, ion gates, and transfer line to the mass spectrometer. The ion gating is accomplished with the aid of two floated pulsers. The separated ions are divided into packets, which are sequentially introduced to the mass spectrometer. Volatile organic compounds (VOCs) are transferred with the aid of nitrogen gas flow from the sample chamber to the APCI source. The operation of the system has been demonstrated using standard compounds. The limits of detection for 2,4-lutidine, (−)-nicotine, and pyridine are 2.02 × 10−7 M, 1.54 × 10−9 mol, and 4.79 × 10−10 mol, respectively. The system was also used to monitor VOCs emitted from the porcine skin after exposure to nicotine patches, and VOCs released from meat undergoing the spoilage process. We believe this simple APCI-PCB-IM-QQQ-MS platform can be reproduced by others to augment the capabilities of the existing MS instrumentation.

Occurrence, distribution, and ecological risk of bisphenol analogues in marine ecosystem of urbanized coast and estuary

Bisphenol analogues are prevalent globally because of rampant usage and imprecise processing techniques, prompting alerts about environmental and health hazards. The method employed in this study by solid phase extraction (SPE) and liquid chromatography-tandem quadrupole mass spectrometer (LC-MS/MS) for both quantification and qualitative analysis of the bisphenol compounds in the surface water samples. The coastal and estuarine surface water of Port Dickson and Lukut ranges from 1.32 ng/L to 1890.51 ng/L of bisphenol analogues. BPF mean concentration at 1143.88 ng/L is the highest, followed by BPA and BPS at 59.01 ng/L and 10.96 ng/L, respectively. Based on RQm for bisphenol analogues, the highest for BPF at 2.49 (RQ > 1, high risk), followed by BPS at 0.12 (0.1 < RQ < 1, medium risk) and BPA at 0.09 (0.1 < RQ < 1, medium risk). The presence and current risk of bisphenols analogues should alert the possible water quality degradation soon.

Two years of volatile organic compound online in situ measurements at the Site Instrumental de Recherche par Télédétection Atmosphérique (Paris region, France) using proton-transfer-reaction mass spectrometry

Abstract. Volatile organic compounds (VOCs) have direct influences on air quality and climate. They indeed play a key role in atmospheric chemistry as precursors of secondary pollutants, such as ozone (O3) and secondary organic aerosols (SOA). In this respect, long-term datasets of in situ atmospheric measurements are crucial for characterizing the variability of atmospheric chemical composition, its sources, and trends. The ongoing establishment of the Aerosols, Cloud, and Trace gases Research InfraStructure (ACTRIS) allows implementation of the collection and provision of such high-quality datasets. In this context, online and continuous measurements of O3, nitrogen oxides (NOx), and aerosols have been carried out since 2012 at the SIRTA (Site Instrumental de Recherche par Télédétection Atmosphérique) observatory, located in the Paris region, France. Within the last decade, VOC measurements were conducted offline at SIRTA, until the implementation of real-time monitoring which started in January 2020 using a proton-transfer-reaction quadrupole mass spectrometer (PTR-Q-MS). The dataset acquired during the first 2 years of online VOC measurements provides insights into their seasonal and diurnal variabilities. The additional long-term datasets obtained from co-located measurements (NOx, aerosol physical and chemical properties, meteorological parameters) are used to better characterize the atmospheric conditions and to further interpret the obtained results. Results also include insights into VOC main sources and the influence of meteorological conditions and air mass origin on their levels in the Paris region. Due to the COVID-19 pandemic, the year 2020 notably saw a quasi-total lockdown in France in spring and a lighter one in autumn. Therefore, the focus is placed on the impact of these lockdowns on the VOC variability and sources. A change in the behaviour of VOC markers for anthropogenic sources was observed during the first lockdown, reflecting a change in human activities. A comparison with gas chromatography data from the Paris city centre consolidates the regional representativity of the SIRTA station for benzene, while differences are observed for shorter-lived compounds with a notable impact of their local sources. This dataset could be further used as input for atmospheric models and can be found at https://doi.org/10.14768/f8c46735-e6c3-45e2-8f6f-26c6d67c4723 (Simon et al., 2022a).