Chromatography Ionization Mass Spectrometry Research Articles

Quantitative Electrolyte Analysis from Large Format Cylindrical Lithium-Ion Cells after Electrolyte Extraction

In 2022, Europe’s carbon dioxide (CO2) emissions made up 11% of the worldwide output and a quarter of it was produced by the transportation sector.[1] To reduce these CO2 emissions the sector is shifting to electric vehicles with lithium-ion cells as energy storage. As lithium-ion cells gain popularity, topics such as cell lifetime and fast charging ability increase significantly. Both are closely linked to electrolyte degradation reactions and can be investigated by analyzing the electrolyte and its decomposition. In industrially produced large format cylindrical lithium-ion cells (46950) the electrolyte amount added to the cell is monitored carefully by the cell manufacturer. Almost no excess electrolyte can be found in commercially produced 46950 cells after the formation process. Few methods are described in literature to extract the electrolyte from the cell materials if no excess electrolyte is present. Thompson et al. outlined a centrifugation method of the cell materials to separate electrolyte from the cell materials.[2] Stockhausen et.al. presented a liquid-liquid extraction for pouch cells by adding solvent to the cell.[3] Grützke et al. performed a supercritical CO2 extraction on cylindrical 18650 cells.[4] Drawbacks to the methods known in literature are that these are either not transferable to a large format cylindrical lithium-ion cell or do not enable a representative recovery of all electrolyte components, such as lithium salts, carbonates and additives.In this research we present a liquid-liquid electrolyte extraction method to achieve representative electrolyte extraction in large format cylindrical lithium-ion cells (46950). The electrolyte extraction was performed in a prototype electrolyte extraction chamber designed at BMW Group.The cells are based on an NMC811/Si-graphite material and produced at the prototype plant at BMW Group in Munich, Germany. In comparison to commercially available lithium-ion cells the composition of all components, such as electrode and electrolyte materials are known. A variation of electrolytes is investigated with conductive salt concentrations of 1-1.5M LiPF6 and solvent mixtures of different carbonates to ensure a variety of applications. Quantitative analysis of the conductive salt is performed with ion chromatography–mass spectrometry (IC-MS). The electrolyte solvents are quantified with a high performance liquid chromatography-Orbitrap-mass spectrometry (HPLC-Orbitrap-MS). These extensive analysis will enable a better understanding of the function, changes and importance of the electrolyte in lithium-ion cells.

Early oil charging from Sinian shales in Ordovician carbonates of the Tabei Uplift, Tarim Basin: Evidence from biomarkers

Despite over 40 years of exploration focusing on the deep to ultra-deep Ordovician carbonates as major hydrocarbon targets in the Tarim Basin, the identification of their source rocks remains elusive. Based on biomarkers, carbon and sulfur isotopes of hydrocarbons, the primary source for the Ordovician petroleum system has been attributed mainly to the lower Cambrian shales, although some oils were likely contributed from the Lower Ordovician source rocks. However, the current understanding of the evolution of the Ordovician petroleum system remains rudimentary, largely due to the complex interplay of multi-source (i.e., the widespread Precambrian shales) hydrocarbon inputs, diagenetic alterations, and tectonic processes over geological time. This study systematically investigates the molecular geochemistry of reservoir bitumen within the Ordovician carbonates from Tabei uplift, coupled with bitumen from the Sinian units at the western edge of the Tarim Basin. Our results indicate that the ion chromatography-mass spectrometry spectra and the saturated to aromatic hydrocarbons ratio of Ordovician reservoir bitumen closely resemble those of Sinian bitumen, as well as the published data of Sinian shales. This coupling linkage is revealed by cross-plots and ternary phase diagrams of various biomarker parameters, which can effectively distinguish the Sinian sources from other sources, i.e., the Lower Cambrian and Ordovician, for the Ordovician reservoir bitumen. Specifically, the ∑n-C21-/∑n-C22+, Pr/Ph, G/C31H22S, C23/C21TT ratios are effective indexes to differentiate these source rocks. By compiling the published organic geochemistry data of oils, it appears to infer that approximately 8.1% of the present-day oils produced from the Ordovician carbonates likely contain some proportion of Sinian-sourced oils. The recognition of Sinian sourced oils contributing to the paleo- and present-day Ordovician petroleum system offers valuable insights for the exploration of deep-ultra deep carbonates in the Tarim Basin, emphasizing the need to consider Precambrian shales as a significant hydrocarbon source.

Rapid bromate determination using short-column ion chromatography-mass spectrometry: Application to bromate quantification during ozonation

A streamlined, precise, and dependable method for the concurrent quantification of bromate has been established, employing ion chromatography in conjunction with electrospray ionization tandem mass spectrometry (IC-ESI-MS/MS). In an effort to expedite sample analysis duration, the AG18 short column was utilized for rapid separation of the specified analytes. Utilizing a blend of water and acetonitrile as the mobile phase within an optimized gradient elution setting, it was possible to achieve satisfactory resolution in under 3 minutes. Specifically, the mixing of acetonitrile in water samples improves the sensitivity and immunity of the method. This phenomenon may be attributed to the similar proportions of acetonitrile in the sample and the mobile phase, which effectively reduces the viscosity and surface tension of the droplets during the ESI process. Detection limits and quantification thresholds were 0.14 µg/L and 0.41 µg/L, respectively. Analyte recoveries, when spiked into tap water between 2.5 µg/L to 50 µg/L, ranged from 69.5 % to 116.7 %; precision metrics, measured as intra- and inter-day relative standard deviations, spanned 5.1–7.9 %. The devised approach encountered minimal interference from prevalent water matrix constituents, including chloride (50–200 mg/L), sulfate (25–200 mg/L), bicarbonate/carbonate (1–6 mM), and natural organic matter (1–8 mg/L). In environmental contexts, this methodology effectively tracked the production of bromate in controlled ozonation experiments conducted in the laboratory. Segmented ozone dosing reduced bromate production when the solution contained low concentrations of DOC, which provides an alternative strategy for controlling bromate production.

Advances in the application of ion chromatography-mass spectrometry in the fields of life and health

Ion chromatography is a technique commonly used to separate strongly polar and ionizable substances; it can be used to separate, identify, and quantify ionizable compounds in complex samples when coupled with mass spectrometry, and is currently being used in the application of food analysis, drug analysis, metabolomics and clinical poisoning analysis. Herein, we review the development of ion chromatography-mass spectrometry (IC-MS), its progress over the past 20 years, and future trends in the abovementioned areas. The IC-MS research progress and applications for the determination of inorganic anions, organic acids, polar pesticides, biogenic amines, and sugars in the food field are discussed. Drug analysis applications are discussed mainly in relation to the analysis of drug impurities, identifying drug degradation products, and determination of plasma concentration, while the separation and analysis of strongly polar metabolites, such as organic acids, sugar phosphates, and nucleotides in biological matrices are discussed in relation to metabolomics. Advances in the analysis of strongly polar or ionizable toxic compounds, such as alkyl methylphosphonic acid, methylphosphonic acid, glyphosate, 3-nitropropionic acid, and indandione rodenticides, are mainly discussed in clinical poisoning analysis field. This paper is expected to become a useful reference for the further expansion and application of IC-MS in the life and health fields.

Hydroxyproline increases inflammation and Uropathogenic E. coli (UPEC) infection in female rats.

Calcium oxalate (CaOx) kidney stones may be associated with urinary tract infections (UTIs). However, the mechanisms for this association are not well-established. The objective of this study was to investigate the effect of oxalate on immunity and UTI development in vivo. Female Sprague-Dawley rats were fed a control diet for 3 days before continuing this diet or starting a 5% Hydroxy-L-proline diet (HLP; oxalate precursor) for 7 days. Rats were subsequently infected transurethrally with Uropathogenic E. coli (UPEC, a bacterium that causes UTI) and sacrificed 3 days later. Urine, blood, kidney, and bladder samples were collected. Urinary oxalate levels, renal CaOx crystal deposition, inflammatory markers, and the bacterial load were assessed using ion chromatography-mass spectrometry, immunohistochemistry, qRT-PCR, western blotting, enzyme-linked immunosorbent assays, or colony forming unit assays. Animals fed HLP and infected with UPEC had a significant increase in urinary oxalate levels, renal CaOx deposition, pro-inflammatory macrophages, pro-inflammatory cytokines, and bacterial loads compared to animals fed the control diet with UPEC infection. In addition, HLP-fed animals had significantly reduced anti-inflammatory renal macrophages and anti-inflammatory cytokine levels in their plasma, urine, and kidneys. These findings suggest that oxalate may play a novel role in the propagation of UTI development.

Highly sensitive two-dimensional ion chromatography mass spectrometry method for nitrite determination in hydroxypropyl methylcellulose

Due to their potential adverse health effects, some N-nitrosamines in drug products are strictly regulated with very low maximum daily intake limits. Nitrosamines can be formed from the reaction of nitrite and secondary or tertiary amines when both species co-exist in the drug synthesis or formulation process. One key strategy to mitigate nitrosamine risk in drugs is to select low-nitrite containing pharma excipients for formulation. It is necessary to develop a sensitive method for trace nitrite determination in pharma excipients as it enables drug producers to study nitrosamine formation kinetics and select excipient suppliers. This study details the development and validation of a two-dimensional ion chromatography mass spectrometry (2D-IC/MS) method for trace nitrite determination in hydroxypropyl methylcellulose (HPMC), one of the most important pharmaceutical excipients used in many drug formulations. The 2D-IC system was operated in heart-cutting mode with a concentrator column coupling the two dimensions. A standard bore anion-exchange column was used in the first dimension (1D) to enable a large volume injection for increased sensitivity and provide improved resolution between nitrite and the interfering chloride peak. A high efficiency microbore anion-exchange column with different selectivity was used in the second dimension (2D) to resolve nitrite from other interfering species. The use of 2D-IC resulted in significantly improved resolution, solving the sensitivity loss issue due to ion suppression from an otherwise 1D separation. MS detection with selective ion monitoring and isotope labeled nitrite internal standard further improve the method specificity, accuracy, and ruggedness, as compared with conductivity detection. For trace determination, it is also extremely important to have a clean blank. For this purpose, a novel cleaning procedure using a strong anion wash was developed to remove nitrite contamination from labware. The optimized method was validated with linearity of nitrite in the concentration range of 18.5–5005.8 ng/g having a regression coefficient of >0.9999, precision with RSD at 3.5–10.1 % and recovery of 90.5–102.4 %. The limit of detection and limit of quantitation were 8.9 and 29.6 ng/g relative to the HPMC sample, or equivalent to 89 and 296 pg/g in the sample solution, respectively.

Doping control analysis of myo-inositol trispyrophosphate and 10 bisphosphonates in equine plasma by ion chromatography-mass spectrometry and its application to clodronic acid horse administration.

Bisphosphonates and myo-inositol trispyrophosphate (ITPP) are two classes of difficult-to-detect polar drugs that are prohibited under the rules of racing. ITPP is a drug capable of increasing the amount of oxygen in hypoxic tissues, and studies have shown that administration of ITPP increases the maximal exercise capacity in mice. The properties of ITPP make it an ideal candidate as a doping agent to enhance performance in racehorses. In recent years, ITPP had indeed been detected in racehorses and confiscated items. As for bisphosphonates, it is especially critical to control their use as since February 2019, the International Agreement on Breeding, Racing and Wagering (IABRW) by the International Federation of Horseracing Authorities (IFHA) had identified specific conditions on which bisphosphonates should not be administered to a racehorse. A recent review of literature shows that there is yet a simultaneous screening method for detecting ITPP and bisphosphonates in equine samples. This paper describes an efficient ion chromatography high-resolution mass spectrometry (IC-HRMS) method for the simultaneous detection of ITPP and 10 bisphosphonates at sub-parts-per-billion (ppb) to low-ppb levels in equine plasma after solid-phase extraction (SPE) and its application to an administration study of clodronic acid in horses.

Abstract A010: Mitochondrial depletion and metabolic reprogramming is a novel phenotype of Lynch syndrome-related endometrial carcinogenesis

Abstract Background: Lynch syndrome (LS), defined by mutations in DNA mismatch repair genes including MSH2, carries a 60% lifetime risk of developing endometrial cancer (EC). Our recent studies in Msh2-deficient mice revealed mitochondrial dysfunction in EC pathogenesis. We aimed to define mechanisms of mitochondrial dysfunction and impact on metabolism to identify targets for EC prevention. Methods: We assessed the effects of MSH2 loss on EC pathogenesis using a novel mouse model (PR-Cre Msh2flox/flox, abbreviated Msh2KO), primary cell lines from this model, and human EC cells with isogenic MSH2-knockdown. mtDNA damage was measured using RT-PCR. Mitochondrial content was quantified in vitro by immunofluorescence (IF) for TOM20 and in vivo by anti-TOM20 immunohistochemistry (IHC). Mitochondrial stress tests (MSTs) assessed mitochondrial function in vitro. Metabolite profiling via high resolution ion chromatography mass spectrometry was conducted on Msh2KO EC and MSH2-intact EC from the Pten +/− mouse model. Glycolysis was suppressed in vitro by replacing glucose with galactose in culture media. Results: Baseline mtDNA damage was elevated in MSH2-deficient MFE280 and RL95-2 EC cell lines by 4.8- to 7.9-fold compared to MSH2-intact KLE and Hec50 cells (p<0.001). MSH2 knockdown increased mtDNA damage in KLE and Hec50 cells by 2.5- to 5.7-fold (p<0.05). MSH2-deficient mouse and human cell lines had lower mitochondrial content compared to MSH2-intact counterparts as indicated by TOM20 staining, with over 60% reductions in mitochondrial volume in MSH2-deficient mouse cell lines and over 95% reductions in MSH2-deficient human EC cells compared to respective controls (p<0.0001). IHC showed reduced mitochondrial content during EC development in Msh2KO mice and in human LS EC tissues. MSTs revealed decreased baseline and induced mitochondrial function in Msh2KO cells relative to controls and in MSH2-deficient human cells (MFE280, RL95-2, and Hec59) compared to MSH2-intact human cells (KLE, Hec1a, Hec50), with p<0.0001. Within the top 10 differentially modulated metabolites in Msh2KO EC compared to Pten +/− EC were glucose 6-phosphate (log2 fold-change (FC) -1.79), mannose 6-phosphate (log2FC -1.77), fructose 6-phosphate (log2FC -1.54), and lactate (log2FC 0.68), padj<0.05. Galactose reduced viability in MSH2-deficient mouse and human cells more than in their MSH2-intact counterparts (p<0.01). Conclusions: We identified mitochondrial depletion as a novel phenotype of MSH2-deficient EC. mtDNA damage in MSH2-deficient cells suggests a role for MSH2 in mtDNA integrity. MSH2-deficient EC is characterized by mitochondrial DNA damage, mitochondrial content reduction, and decreased mitochondrial function. Decreased mitochondrial respiration for energy production facilitates metabolic reprogramming toward glycolysis, signified by increased usage of glycolytic intermediates and dependence on glycolysis for survival. Mitochondrial and metabolic aberrations could be evaluated as novel biomarkers for EC development and targets for prevention in women with LS. Citation Format: Mikayla B. Bowen, Brenda Melendez, Anna Zal, Collene Jeter, Wai Kin Chan, Lin Tan, Philip Lorenzi, Diana Moreno, Leah Peralta, Qian Zhang, Nisha Gokul, Karen Lu, Hyun-Eui Kim, Melinda S. Yates. Mitochondrial depletion and metabolic reprogramming is a novel phenotype of Lynch syndrome-related endometrial carcinogenesis [abstract]. In: Proceedings of the AACR Special Conference on Endometrial Cancer: Transforming Care through Science; 2023 Nov 16-18; Boston, Massachusetts. Philadelphia (PA): AACR; Clin Cancer Res 2024;30(5_Suppl):Abstract nr A010.

Rapid analysis of trace pollutants chlorates, perchlorates, and four xanthates in water based on IC-MS combined technology

Water, as the source of life, plays a crucial role in life activities. It also acts as a solvent, allowing toxic and harmful substances to migrate through the water environment. In this study, an analytical method based on ion chromatography-mass spectrometry (IC-MS) is established for the direct determination of trace chlorates, perchlorates, and four xanthates in water. The Dionex IonPac AS20 chromatography column is used as the analytical column, and the CR-TC device automatically generates KOH eluent and sets up a multi-step gradient program for elution. The Dionex ADRS 600 self-circulating regeneration ion suppressor (2 mm) generates H+ through electrolysis of water, replacing metal ions in the sample solution and eluent, enabling direct tandem ion chromatography and mass spectrometry. The water sample is directly measured by IC-MS after being filtered by a hydrophilic polytetrafluoroethylene (PTFE) filter head. The results indicate that chlorate and perchlorate show good linearity in the range of 0.1–100 ng mL−1, with a quantification limit of 0.3 μg L−1. The four xanthates exhibit a good linear relationship in the range of 0.5–500 ng mL−1, and the quantification limit can be reduced to 1 μg L−1. The method offers advantages such as high recovery rate, good stability, and strong reproducibility. It shows high consistency with the results detected by the LC-MS method, but with the added benefits of being more advanced and time-saving. This innovative technology provides a new detection method for trace pollutants in water, which can aid in the prevention and control of pollutants in the water environment.

Parts per billion of nitrite in microcrystalline cellulose by ion chromatography mass spectrometry with isotope labeled internal standard

Regulatory authorities like the U.S. Food and Drug Administration (FDA) have set strict specification levels for N-nitrosamines in finished drug products. Nitrite is a potential precursor for the formation of probable carcinogenic N-nitrosamines when secondary or tertiary amines are also present in the active pharmaceutical ingredient (API) synthesis or drug formulation process. An accurate and sensitive determination of nitrite will be useful when a drug product manufacturer chooses to investigate the reaction kinetics between nitrite and amines or to select appropriate excipients for its drug formulation. Pharmaceutical excipient manufacturers may also need an accurate nitrite measurement to investigate the nitrite content in their excipients. This study details the development and validation of an ion chromatography mass spectrometry (IC-MS) method for trace nitrite determination in microcrystalline cellulose materials, one of the important pharmaceutical excipients used in many drug formulations. MS operated under selected ion monitoring mode was used to solve the commonly encountered interference issue with conductivity detection, and nitrite isotope internal standard was employed to address the ion suppression issue with MS detection. The installation of an after-column “jumper” to flush water with an auxiliary pump through the MS when it is not used for data collection avoided sensitivity loss due to trace salt accumulation in the ion source. Validation of the optimized method was satisfactory, with linearity of nitrite in the concentration range of 0.02–7.50 ppm (µg/g) having a regression coefficient of > 0.999, precision of RSD < 9.5% at 0.03 ppm and RSD < 3.4% at 0.4 ppm and recovery of 92.0–103.0%. The limit of detection and limit of quantitation were 0.005 and 0.016 ppm, respectively.

Deciphering the human urine matrix: a new approach to simultaneously quantify the main ions and organic compounds by ion chromatography/mass spectrometry (IC-MS).

Analyzing the composition of (human) urine plays a major role in the fields of biology and medicine. Organic molecules (such as urea, creatine) and ions (such as chloride, sulfate) are the major compounds present in urine, the quantification of which allows for the diagnosis of a subject's health condition. Various analytical methods have been reported for studying urine components and validated on the basis of known and referenced compounds. The present work introduces a new method able to simultaneously determine both major organic molecules and ions contained in urine, by combining ion chromatography using a conductimetric detector with mass spectroscopy. The analysis of organic and ionized compounds (anionic and cationic) was achieved in double injections. For quantification, the standard addition method was used. Human urine samples were pre-treated (diluted and filtered) for IC-CD/MS analysis. The analytes were separated in 35 min. Calibration ranges (0-20 mg.L-1) and correlation coefficients (> 99.3%) as well as detection (LODs < 0.75 mg.L-1) and quantification (LOQs < 2.59 mg.L-1) limits were obtained for the main organic molecules (lactic, hippuric, citric, uric, oxalic acids, urea, creatine, and creatinine) and ions (chloride, sulfate, phosphate, sodium, ammonium, potassium, calcium, and magnesium) contained in urine. The intra- and inter-day accuracies of the analytes consistently ranged from 0.1 to 5.0%, and the precision was within 4.0%. For all analytes, no significant matrix effects were observed, and recoveries ranged from 94.9 to 102.6%. Finally, quantitative results of analytes were obtained from 10 different human urine samples.

A simple ion chromatography-mass spectrometry method for amino acid analysis in beer.

The amino acid footprint of different beer samples was analyzed using ion chromatography coupled with electrospray ionization mass spectrometry. A tailor-made polymer-based cation-exchange resin was operated with a mass spectrometry-compatible eluent under isocratic conditions on a standard high-performance liquid chromatography system coupled to a single quadrupole mass spectrometer using formic acid as a volatile eluent ion source. The partially separated peaks of the isomeric pair isoleucine/leucine were processed according to their area response ratio using vertical peak splitting or Gaussian fit. Additionally, the chromatographic resolution of the isomers was optimized with an adjusted, solely aqueous mobile phase from 0.85 to 2.92. Ion suppression in the electrospray ion source was investigated for the derivatization-free method and found to be insignificant (recovery value 100±15%) for 15 out of the 20 analytes. Quantitative results for various beer and mixed-beer beverages were found to be in high agreement with existing methods. Simultaneous photometric detection demonstrated the method's ability to successfully remove most of the interfering matrix compounds.

An Explorative Study into the Aetiology of Developmental Dysplasia of the Hip Using Targeted Urine Metabolomics

Developmental dysplasia of the hip (DDH) is the most prevalent congenital musculoskeletal disorder, yet its cause remains unknown. Adequate nutrient provision and coordinated electron exchange (redox) processes are critical for foetal growth and tissue development. This novel study sought to explore specific biochemical pathways in skeletal development for potential involvement in the aetiology of DDH. Spot urine samples were collected from infants, aged 13-61 days, with and without DDH. Ion chromatography-mass spectrometry was used to quantify thiosulphate, sulphate, nitrate, and phosphate, whilst nitrite was quantified using high-performance liquid chromato-graphy. Thiobarbituric acid reactive substances (TBARS) were measured as markers of lipid peroxidation. Creatinine and osmolality were determined by a 96-well plate assay and micro-osmometer to potentially normalise values for renal function, lean body mass, and hydration status. Urine samples were analysed from 99 babies: 30 with DDH and 69 age-matched non-DDH controls. Thiosulphate, TBARS, and creatinine concentrations differed between the DDH group and the controls (p = 0.025, 0.015, and 0.004 respectively). Urine osmolality was significantly lower in DDH compared to the controls (p = 0.036), indicative of the production of a more diluted urine in DDH infants. Following adjustment for osmolality, significant differences became apparent in urinary sulphate levels in DDH (p = 0.035) whereas all other parameters were similar between the groups. This is the first study to assess the potential role of these inorganic anions in DDH. The higher levels of sulphate found in infants with DDH suggests either enhanced intake from milk, increased endogenous formation, or impaired renal reabsorption. This investigation demonstrates the power of urine metabolomics and highlights the importance of normalisation for hydration status to disentangle developmental disorders. Our results strongly suggest that DDH is a systemic disease associated with altered uptake, formation, or handling of sulphate. There is potential for new opportunities in the prevention or treatment of DDH via nutritional intervention.

Oudemansiella raphanipies Polysaccharides Improve Lipid Metabolism Disorders in Murine High-Fat Diet-Induced Non-Alcoholic Fatty Liver Disease.

Oudemansiella raphanipies, also called “Edible Queen,” is a mushroom that possesses antioxidant, anti-inflammatory, anti-bacterial, anti-tumor and immunity-enhancing properties. The present study aimed to assess the effect of O. raphanipies-derived polysaccharide (ORPS) on the progression of nonalcoholic fatty liver disease (NAFLD) in mice. We studied the structure of ORPS-1 by high-performance gel permeation chromatography (HPGPC), ion chromatography-mass spectrometry (GC-MS), and Fourier transform-infrared spectroscopy (FT-IR). ORPS-1 mainly comprised galactose, fucose, glucose, mannose, and xylose, following an 18:6:6:4:1 molar ratio. In addition, the therapeutic effect as well as a potential mechanism of ORPS-1 in the treatment of high-fat diet (HFD)-induced NAFLD were investigated. The results showed that ORPS-1 improved liver function, ameliorated liver steatosis, and reduced lipid droplet accumulation in HFD mice. A metabolomics approach with GC-MS was utilized to evaluate liver improvement by ORPS-1 treatment. Principal component analysis showed that liver metabolic profiling was significantly altered by HFD feeding or treatment with an intermediate dose of ORPS-1 in mice compared with that of control mice. By investigating the metabolic pathways with identified biomarkers, various pathways such as steroid biosynthesis, valine, leucine, and isoleucine biosynthesis, glycerol phospholipid metabolism, glyceride metabolism, and arginine and proline metabolism in HFD mice were observed to be significantly influenced by ORPS-1 treatment. The results indicate ORPS-1 metabolic effects on liver tissues, provide methods for assessing the molecular impact of ORPS-1 on NAFLD, and suggest the potential mechanism underlying its health benefits.

Comparative Metabolomics of Small Molecules Specifically Expressed in the Dorsal or Ventral Marginal Zones in Vertebrate Gastrula.

Many previous studies have reported the various proteins specifically secreted as inducers in the dorsal or ventral regions in vertebrate gastrula. However, little is known about the effect on cell fate of small molecules below 1000 Da. We therefore tried to identify small molecules specifically expressed in the dorsal marginal zone (DMZ) or ventral marginal zone (VMZ) in vertebrate gastrula. Small intracellular and secreted molecules were detected using explants and supernatant samples. Hydrophilic metabolites were analyzed by capillary ion chromatography–mass spectrometry and liquid chromatography–mass spectrometry, and lipids were analyzed by supercritical fluid chromatography–tandem mass spectrometry. In total, 190 hydrophilic metabolites and 396 lipids were identified. The DMZ was found to have high amounts of glycolysis- and glutathione metabolism-related metabolites in explants, and the VMZ was richer in purine metabolism-related metabolites. We also discovered some hydrophilic metabolites and lipids differentially contained in the DMZ or VMZ. Our research would contribute to a deeper understanding of the cellular physiology that regulates early embryogenesis.

Hydroxyproline stimulates inflammation and reprograms macrophage signaling in a rat kidney stone model

Meals rich in oxalate are associated with calcium oxalate (CaOx) kidney stone disease. Hydroxy-L-proline (HLP) is an oxalate precursor found in milk and collagen-containing foods. HLP has been shown to induce CaOx crystal formation in rodents. The purpose of this study was to evaluate the effect of HLP induced oxalate levels on inflammation and renal leukocytes during crystal formation. Male Sprague-Dawley rats (6–8 weeks old) were fed a control diet containing no oxalate for 3 days before being randomized to continue the control diet or 5% HLP for up to 28 days. Blood, 24 h urine, and kidneys were collected on Days 0, 7, 14, or 28. Urinary oxalate levels, crystal deposition, and renal macrophage markers were evaluated using ion chromatography-mass spectrometry, immunohistochemistry, and qRT-PCR. Renal leukocytes were assessed using flow cytometry and RNA-sequencing. HLP feeding increased urinary oxalate levels and renal crystal formation in animals within 7 days. HLP also increased renal macrophage populations on Days 14 and 28. Transcriptome analysis revealed that renal macrophages from animals fed HLP for 7 days were involved in inflammatory response and disease, stress response to LPS, oxidative stress, and immune cell trafficking. Renal macrophages isolated on Day 14 were involved in cell-mediated immunological pathways, ion homeostasis, and inflammatory response. Collectively, these findings suggest that HLP-mediated oxalate levels induce markers of inflammation, leukocyte populations, and reprograms signaling pathways in macrophages in a time-dependent manner. Additional studies investigating the significance of oxalate on renal macrophages could aid in our understanding of kidney stone formation.

Root Canal Obturation by Electrochemical Precipitation of Calcium Phosphates

Achieving adequate disinfection and preventing reinfection is the major goal in endodontic treatment. Variation in canal morphology and open porosity of dentine prevents achieving complete disinfection. Questionable biocompatibility of materials as well as a lack of sealing ability questions the usefulness of current obturation methods. With a novel disinfection approach based on the use of boron-doped diamond (BDD) electrodes having shown promising results it was the goal of this series of experiments to investigate the possibility of BDD-mediated in situ forming of a biocompatible obturation material. A combination of calcium phosphate and maleic acid was used as precursor solution while Ion Chromatography Mass Spectrometry (IC-MS), Raman spectroscopy (RAMAN), X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDX), scanning electron microscopy (SEM), dye penetration and micro-computed tomography (µCT) were applied for characterizing the precipitate. It was possible to achieve a BDD-mediated precipitation of brushite in a clinically applicable timeframe. However, tight sealing of the canal system based on brushite could not be achieved.

Advances in mass spectrometry for molecular characterization of oil sands naphthenic acids and process chemicals in wetlands

Advances in mass spectrometry in the authors’ and key collaborators’ research are reviewed for analysis of oil sands naphthenic acids fraction compounds (NAFCs) and industrial process chemicals, sulfolane and alkanolamines, in wetlands. Focus is given to developments of analyses of NAFCs in constructed wetland treatment systems and natural wetlands in the Athabasca oil sands region, Alberta, Canada. The analytical developments are applied to show the utility of wetlands to sequester and oxidize oil sands naphthenic acids. The advancements in molecular characterization led to the first application of high-resolution mass spectrometry (Fourier transform ion-cyclotron resonance and Orbitrap mass spectrometry) for elucidation of toxic mono- and di-carboxylic NAFCs in oil sands environmental samples. Key findings reveal that oil sands NAFCs are not limited to saturated structures but contain a diverse range of components, many of which contain S, N, heteroatomic species and aromatic species. Other developments of mass spectrometry methods for industrial process chemicals show for the first time that the completely water-miscible chemical, sulfolane, translocate to upper portions of cattails at natural wetland sites in the Canadian environment. Likewise, wetland-plant mediated changes of complex mixtures of alkanolamines were revealed based on the coupling of ion chromatography mass spectrometry and ultrahigh resolution mass spectrometry. The advances in mass spectrometry are of particular benefit to Canada, for development of soil and water quality guidelines for oil sands NAFCs and process chemicals. In turn, the water quality guidelines serve to protect Canadian aquatic environments.

Towards a more complete glycome: Advances in ion chromatography-mass spectrometry (IC-MS) for improved separation and analysis of carbohydrates

To date, few tools are available for the analysis of the glycome without derivatization, a process which is known to introduce issues such as differential loss of sialic acid and incomplete labeling. We have previously reported the use of ion chromatography-mass spectrometry (IC-MS) to analyze native sialylated and sulfated glycans. Here, we introduce improvements to IC column technology, enabling the separation of neutral glycans while maintaining charge separation capabilities. When implemented in an IC-MS workflow, this enables the structural characterization of a broad array of chemically distinct glycans. With the newly developed IC column and modified IC-MS instrumentation configuration, we qualitatively investigated O-glycome profiles in bovine fetuin and porcine gastric mucins. The improved chromatographic resolution in combination with high-resolution MS data present a powerful tool for glycan structural identification.

Metabolomic Analysis of Small Extracellular Vesicles Derived from Pancreatic Cancer Cells Cultured under Normoxia and Hypoxia.

Extracellular vesicles (EVs) released from cancer cells contribute to various malignant phenotypes of cancer, including metastasis, cachexia, and angiogenesis. Although DNA, mRNAs, miRNAs, and proteins contained in EVs have been extensively studied, the function of metabolites in EVs remains unclear. In this study, we performed a comprehensive metabolomic analysis of pancreatic cancer cells, PANC-1, cultured under different oxygen concentrations, and small EVs (sEVs) released from them, considering the fact that hypoxia contributes to the malignant behavior of cells in pancreatic cancer, which is a poorly diagnosed cancer. sEVs were collected by ultracentrifugation, and hydrophilic metabolites were analyzed using capillary ion chromatography-mass spectrometry and liquid chromatography-mass spectrometry, and lipids were analyzed by supercritical fluid chromatography-tandem mass spectrometry. A total of 140 hydrophilic metabolites and 494 lipids were detected in sEVs, and their profiles were different from those in cells. In addition, the metabolomic profile of sEVs was observed to change under hypoxic stress, and an increase in metabolites involved in angiogenesis was also detected. We reveal the hallmark of the metabolites contained in sEVs and the effect of tumor hypoxia on their profiles, which may help in understanding EV-mediated cancer malignancy.