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Almost no pharmacokinetic compounds to date have been precisely linked with the activity of their herbal or Traditional Chinese Medicine (TCM) formula. This creates challenges for pharmacokinetic significance and application of the TCM. In our study, a sensitive and selective liquid chromatography-tandem mass spectrometry (LC–MS/MS) method was developed to quantitatively or qualitatively determine multiple-components (tanshinol, ferulic acid, protocatechuic acid, rosmarinic acid, salvianolic acid B, baicalin and 9′-methyl lithospermate B) in rat plasma following the oral administration of Denshen-Chuanxiong-Honghua (DCH) extract (20 g/kg). Chromatographic separation was carried out on a 300SB-C18 column using a gradient elution with a mobile phase composed of acetonitrile-water (containing 0.1% formic acid) at a flow rate of 1.0 mL/min. Determination by mass spectrometry (MS) was conducted in multiple reaction monitoring (MRM) mode with negative electrospray ionization. The validated method exhibited good linearity, with correlation coefficients greater than 0.9949 over a wide concentration range, and the lower limits of quantification were 2.09–12.2 ng/mL for the 5 analytes. This assay was successfully applied to investigate the pharmacokinetics of 5 compounds in rat plasma after the oral administration of DCH extracts. In addition, the anti-oxidant capacities of the 5 active ingredients of DCH extract in vitro and the total absorbed DCH extract in vivo were investigated at different concentrations during pharmacokinetic studies. [ABSTRACT FROM AUTHOR]

Highly toxic insecticides (HTIs) belonging to different chemical groups are dangerous to pollinating organisms, even in sublethal doses. An important objective of this study was to develop a method to determine over fifty HTIs at very low concentrations in the bee matrix. The novelty of this research involved obtaining extract completely free from beewaxes, lipids and proteins using EMR-lipid (enhanced matrix removal-lipid), chitin and Z-Sep+ (zirconium oxide and C18 dual-bonded to silica) as clean-up sorbents. Different parameters, such as weight of bees, extraction solvent, and freezing time were evaluated. Determinations were made using liquid chromatography-tandem mass spectrometry (LC-MS/MS). EMR-lipid allows for removing most of the fatty co-extracts and increases the overall performance of the method by reducing the matrix effects (ME) without significant analyte loss. The established modified QuEChERS method based on 1% acetic acid in acetonitrile extraction followed by EMR-lipid clean-up was validated at three different spiking levels (0.001, 0.01 and 0.1 mg kg −1 ). Precision, calculated as relative standard deviation (RSD), was below 20%. The proposed method was used to determine sublethal doses of these insecticides in real samples of dead honeybees. [ABSTRACT FROM AUTHOR]

A sensitive and specific LC/MS/MS method was developed for the simultaneous analysis of 35 compounds used for treating hypertension as adulterants in dietary supplements. The method was validated for specificity, linearity, accuracy, precision, limit of detection, limit of quantitation, stability and recovery. The limit of detection and limit of quantitation ranged from 0.20 to 20.0 and 0.50 to 60.0 ng/g, respectively. The linearity was good ( r 2 > 0.999), with intra- and interday precision levels of 0.43-7.87% and 0.65-9.95% and the intra- and interday accuracies of 84.36-115.82% and 83.78-118.69%, respectively. The stability (relative standard deviation) was <14.75%. The mean recovery was 80.81-117.86% (relative standard deviation <10.00%). Ninety-seven commercial dietary supplements available in South Korea were analyzed. While none contained detectable amounts of the 35 antihypertensive compounds, the developed LC/MS/MS procedure can be used for routine analysis to monitor illegal adulteration in various forms of dietary supplements. [ABSTRACT FROM AUTHOR]

A rapid, sensitive and selective liquid chromatography-tandem mass spectrometry (LC-MS/ MS) method was developed and validated for the trace analysis of three potential genotoxic impurities in rizatriptan benzoate drug sample. LC-MS/MS analysis of these impurities was done on symmetry C-18 (100 mm x 4.6 mm, 3.5 μm) column. In this method, 0.2% formic acid was used as mobile phase A and mixture of methanol and acetonitrile (5:95,v/v) used as mobile phase B in gradient mode with the flow rate of 0.8  mL/min. The method was developed with the short run time of 12 minutes. Triple quadrupole mass detector coupled with positive electrospray ionization was used for the quantification of genotoxic impurities in multiple reaction monitoring (MRM) mode. The method was linear in the range of 2.97 ppm to 74.16 ppm for N-(3-chloropropyl)-N,N- dimethylamine (CDA), 3.02 ppm to 75.44 ppm for l-(4-hydrazinophenyl) methyl-l,2,4-triazole (HMT) and 3.02 ppm to 75.52 ppm for l-(4-nitrophenyl) methyl-1,2,4-triazole (NMT) with a correlation coefficient not less than 0.9995. The accuracy of the method was in the range of 92.75% to 102.49% for all three potential genotoxic impurities (PGIs). No impurities were identified in the rizatriptan benzoate active pharmaceutical ingredient sample. This method is able to quantify the impurities at very low levels. [ABSTRACT FROM AUTHOR]

An improved analytical method compared with conventional ones was developed for simultaneous determination of 13 mycotoxins (deoxynivalenol, nivalenol, 3-acetylnivalenol, aflatoxin B1, aflatoxin B2, aflatoxin G1, aflatoxin G2, fumonisin B1, fumonisin B2, T-2, HT-2, zearalenone, and ochratoxin A) in cereal grains by liquid chromatography-tandem mass spectrometry (LC/MS/MS) after a single immunoaffinity column clean-up. The method showed a good linearity, sensitivity, specificity, and accuracy in mycotoxin determination by LC/MS/MS. The levels of 13 mycotoxins in 5 types of commercial grains (brown rice, maize, millet, sorghum, and mixed cereal) from South Korea were determined in a total of 507 cereal grains. Mycotoxins produced from Fusarium sp. (fumonisins, deoxynivalenol, nivalenol, and zearalenone) were more frequently (more than 5%) and concurrently detected in all cereal grains along with higher mean levels (4.3-161.0 ng/g) in positive samples than other toxins such as aflatoxins and ochratoxin A (less than 9% and below 5.2 ng/g in positive samples) from other fungal species. [ABSTRACT FROM AUTHOR]

Enzyme-linked immunosorbent assay (ELISA) and liquid chromatography/tandem mass spectrometry (LC/MS/MS) were compared for analyzing microcystins in water. ELISA results of microcystin-LR spiked into raw water samples were close to the spike concentrations, but method variability was ±25%. However, ELISA-derived microcystin-LA concentrations were two to three times higher than the spike concentrations obtained using the kit-provided microcystin-LR standards, indicating the need for variantappropriate ELISA standards. LC/MS/MS results agreed with spike concentrations for all variants in reagent water, but matrix suppression was observed in some raw waters. In bench-scale studies, ozonated microcystins generated low-level positive responses by ELISA and a protein phosphatase inhibition assay, even though microcystins were not detected by LC/MS/MS. These findings indicate that ELISA results--particularly in treated water--should be interpreted with caution because of the possibility of falsepositives, relatively high variability, and differential detection of some variants. [ABSTRACT FROM AUTHOR]

A rapid and sensitive high-performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed and validated to quantify tilmicosin in pig plasma. Plasma samples were prepared by liquid-liquid extraction. Chromatographic separation was achieved on a C18 column (2.1 × 30 mm, 3.5 μm) using acetonitrile-water (90:10, v/v; water included 0.1% formic acid) as the mobile phase. Mass detection was carried out using positive electrospray ionization in multiple reaction monitoring mode. The calibration curve was linear from 0.5 to 2000 ng/mL ( r2 = 0.9998). The intra- and inter-day accuracy and precision were within the acceptable limits of ±10% for all tilmicosin concentrations. The recoveries ranged from 95 to 99% for the three tested concentrations. The LC-MS/MS method described herein was simple, fast and less laborious than other methods, achieved high sensitivity using a small sample volume, and was successfully applied to pharmacokinetic studies of tilmicosin enteric granules after oral delivery to pigs. In comparison with tilmicosin premix, tilmicosin enteric granules slowed the elimination rate of tilmicosin, prolonged its period of action and significantly improved its bioavailability. [ABSTRACT FROM AUTHOR]

A series of carbamate derivatives of the antileukemic sesquiterpene melampomagnolide B (MMB) has been synthesized utilizing a 1,2,4-triazole carbamate conjugate of MMB as an intermediate synthon. Five imidazole- and benzimidazole-carbamate analogs of MMB ( 8a–8e ) were prepared and evaluated for anti-leukemic activity against cultured M9 ENL1 AML cells. All the analogs exhibited improved anti-leukemic activity (EC 50 = 0.90–3.93 μM) when compared to parthenolide and the parent sesquiterpene, MMB (EC 50 = 7.0 μM and 15.5 μM, respectively). The imidazole carbamate analog, 8a (EC 50 = 0.9 μM), was 16 times more potent than MMB. The comparative bioavailabilities of 8a and MMB were determined in BALB/c mice following oral dosing of these compounds. It has been demonstrated that the absolute plasma bioavailabilities of MMB and 8a were 6.7 ± 0.8%, and 45.5 ± 2%, respectively. These results indicate that, compared to MMB, the PK parameters for 8a display significantly improved bioavailability and exposure after oral administration. Analog 8a is considered to be a potential clinical candidate for treatment of acute myelogenous leukemia. [ABSTRACT FROM AUTHOR]

A rapid dispersive micro-solid phase extraction (D-μ-SPE) combined with LC/MS/MS method was developed and validated for the determination of ketoconazole and voriconazole in human urine and plasma samples. Synthesized mesoporous silica MCM-41 was used as sorbent in d-μ-SPE of the azole compounds from biological fluids. Important D-μ-SPE parameters, namely type desorption solvent, extraction time, sample pH, salt addition, desorption time, amount of sorbent and sample volume were optimized. Liquid chromatographic separations were carried out on a Zorbax SB-C18 column (2.1 × 100 mm, 3.5 μm), using a mobile phase of acetonitrile-0.05% formic acid in 5 m m ammonium acetate buffer (70:30, v/v). A triple quadrupole mass spectrometer with positive ionization mode was used for the determination of target analytes. Under the optimized conditions, the calibration curves showed good linearity in the range of 0.1-10,000 μg/L with satisfactory limit of detection (≤0.06 μg/L) and limit of quantitation (≤0.3 μg/L). The proposed method also showed acceptable intra- and inter-day precisions for ketoconazole and voriconazole from urine and human plasma with RSD ≤16.5% and good relative recoveries in the range 84.3-114.8%. The MCM-41-D-μ-SPE method proved to be rapid and simple and requires a small volume of organic solvent (200 μL); thus it is advantageous for routine drug analysis. [ABSTRACT FROM AUTHOR]

Berberine (BBR) is a bioactive plant ingredient derived from the roots and bark of Berberis aristata and Coptis chinensis and has a wide variety of pharmacological effects. 8-cetylberberine (8-BBR-C16) is the berberine (BBR) derivative reconstructed from adding octadecyl at C-8 of BBR to enhance its activity. This study presents a reliable method for the determination of BBR and 8-BBR-C16 in rat plasma, urine and feces. BBR and 8-BBR-C16 were determined by HPLC-UV after liquid-liquid extraction for plasma samples, and solid-phase extraction for urinary and fecal samples. The method was linear over the concentration range of 10-300 ng·ml −1 for the plasma samples, 25-2000 ng·ml −1 for the urinary samples, and 100-2000 ng·g −1 for the fecal samples. Furthermore, a metabolic investigation on urine was performed by LC/MS/MS analysis to identify the structures of 8-BBR-C16 metabolites by full scan and product ion scan. Adult Sprague-Dawley rats were divided into two groups. In the control group, rats received 80 mg·kg −1 BBR, and in the drug-treated group, rats received 80 mg·kg −1 8-BBR-C16. The results indicate that there were significant differences in the pharmacokinetic parameters and in the accumulated excretion levels between the control group and the drug-treated group. The C max and AUC 0- t of 8-BBR-C16 were 2.8 and 12.9 times higher than those of BBR, and the relative bioavailability of BBR to 8-BBR-C16 was 7.7%. The total excretion amount through the urine and feces of 8-BBR-C16 was 76.9%, but that of BBR was only 20.5%. Additionally, 8-BBR-C16 was metabolized in rat urine with phase I demethylation and phase II glucuronidation or sulfation. [ABSTRACT FROM AUTHOR]

Oven dried cut stigmas ofCrocus sativusL. cultivated in Eskisehir and Safranbolu regions of Turkey were subjected to micro distillation to extract steam volatiles. They were then analysed by Gas Chromatography and Gas Chromatography/Mass Spectrometry, simultaneously. The colour compounds were extracted with 80% methanol and analysed by High Pressure Liquid Chromatography HPLC/DAD and HPLC/MS/MS. The activities of the extracts of saffron against 2,2ʹ-azinobis-3-ethylbenzothiazoline-6-sulphonic acid free radical (ABTS●+) were investigated using on-line (HPLC-ABTS●+) and off-line methods. Safranal (62.1 and 49.3%) and α-isophorone (10.0 and 16.3%) were found as the characteristic aromatic volatiles in the Eskisehir and Safranbolu samples, respectively. Crude saffron extracts showed high total antioxidant activity against ABTS●+radical. [ABSTRACT FROM AUTHOR]

• We quantified drugs and metabolite in saponified brain using LC/MS/MS. • Saponified brain in the cranium was immersed in seawater for over 10 years. • Diphenhydramine, haloperidol, and reduced haloperidol were identified and quantified. • Saponified tissues can be applied as an alternative specimen for forensic toxicology. In forensic toxicology, blood and urine specimens are commonly used for detecting and quantifying drugs and their metabolites. When the cadaver is so damaged or decomposed such that the specimens mentioned above cannot be collected, it is necessary to perform drug analysis using alternative specimens such as hair, nails, oral fluids and meconium. Adipocere is resistant to further degradation; it is thus possible to be used as an alternative specimen to analyze drugs and their metabolites. Some researchers indeed have reported drug concentrations in saponified samples that were collected years after decedents' deaths. In this study, we subjected saponified brain, which remained under sea for over 10 years after death, to forensic toxicological analysis using liquid chromatography/tandem mass spectrometry (LC/MS/MS). Using product ion scan analysis, we confirmed the presence of diphenhydramine, haloperidol, and reduced haloperidol, a metabolite of haloperidol. In addition, drugs and metabolite quantification were performed using the standard addition method. Correlation coefficients of the calibration curves were over 0.98. Analyte concentrations in the saponified brain were as follows: diphenhydramine was 1.84 ng/g, haloperidol was 1.30 ng/g, and reduced haloperidol was 3.02 ng/g. Our results suggest that it can be possible to quantify not only parent drugs but also their metabolites in saponified brain. These findings indicate that saponified tissues could be applied as alternative specimens for forensic toxicology, and could be useful as supporting information for victim identification. [ABSTRACT FROM AUTHOR]

Sonchus oleraceus (L.) L. (Asteraceae) is an edible wild plant, known for its uses in traditional medicine. The aim of this study is to explore the phytochemical composition of the aerial parts (AP) and roots (R) of aqueous extracts of Sonchus oleraceus L. growing in Tunisia, using liquid chromatography-tandem mass spectrometry(LC/MS/MS), and determine the content of polyphenols and antioxidant activities. Results showed that aqueous extracts of AP and R contained, respectively, 195.25±33 μg/g and 118.66±14 μg/g gallic acid equivalent (GAE), and 52.58±7 μg/g and 3.2±0.3μg/g quercetin equivalent. AP and R extracts also contained tannins, 581.78±33 μg/g and 948.44±19 μg/g GAE. The AP extract in the 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) scavenging activities, hydroxyl radical scavenging (OH-) and in cupric reducing antioxidant activity (CUPRAC) assays were respectively 0.325±0.036 mg/mL, 0.053±0.018 mg/mL, 0.696±0.031 mg/mL and 60.94±0.004 μMTE/g, while the R extract using the same assays showed, 0.209±0.052 mg/mL, 0.034±0.002 mg/mL, 0.444±0.014 mg/mL and 50.63±0.006 μM Trolox equivalent/g, respectively. A total of 68 compounds were tentatively identified by LC/MS/MS in both extracts in which quinic acid, pyrogallol, osthrutin, piperine, gentisic acid, fisetin, luteolin, caffeic acid, gingerol, were the most abundant in the LC/MS/MS spectrum. Many of these metabolites were found for the first time in Tunisian Sonchus oleraceus L. which may take account for the antioxidant activities exhibited by the plant., (© 2023 Wiley-VHCA AG, Zurich, Switzerland.)

Achillea (Asteraceae) species have been traditionally used for their different therapeutical properties. In this study, phytochemical composition of aerial parts of A. sintenisii which is endemic in Turkey was determined with Liquid chromatography/mass spectrometry/mass spectrometry (LC/MS/MS). To evaluate the wound healing potential, the cream formulation prepared from A. sintenisii was tested on the linear incision wound model in mice. In vitro enzyme inhibitory activity tests were performed on elastase, hyaluronidase, and collagenase. In the histopathological examination, angiogenesis and granulation tissue formation were significantly increased in A. sintenisii treatment groups compared to the negative control group. As a result of this study, it is thought that the enzyme inhibition and antioxidant activity of the plant may contribute to the wound healing process. According to LC/MS/MS analysis result, quinic acid (24.261 μg/mg extract) and chlorogenic acid (14.97 μg/mg extract) were identified as main constituents of the extract., (© 2023 Wiley-VHCA AG, Zurich, Switzerland.)

Monitorting of plant protection product residues was performed in 12 grape and 66 wine samples of “Malvasia Istriana” variety, produced in Istria winegrowing region of Croatia and Slovenia. The samples were analysed for the presence of 169 different active compounds using two multiresidual analytical methods: gas chromatography coupled with mass spectrometry and liquid chromatography coupled with tandem mass spectrometry. Residues were found in 58.3% of all the inspected grape samples and in 28.8% of all the inspected wine samples. Beside that contents of residues in grapes were below 10% of maximum residue level values and they should not represent any risk for “Malvasia Istriana” grape or wine consumers. [ABSTRACT FROM AUTHOR]

The right choice of analytical methods for plant allergen quantification is a deciding factor for the correct assessment and labeling of allergens in processed food in view of consumer protection. The aim of the present study was to develop a validated target peptide multi-method by LC/MS/MS providing high specificity and sensitivity for plant allergen protein detection, plant identification in vegan or vegetarian products using peptide markers for quantification. The methodical concept considers the selection of target peptides of thermostable allergenic plant proteins ( Gly m6 soy, Ses i6 sesame and β-conglutin from white lupine) by data base research, BLAST and in silico digestion using Skyline software. Different allergenic concentration levels of these proteins were integrated into our own reference bakery products and quantified with synthesized isotopically labeled peptides after in-solution digestion using LC/MS/MS. Recovery rates within the range of 70–113% and LOQ of 10 ppm–50 ppm (mg allergenic food/kg) could be determined. The results are independent of thermal processing applied during baking and of epitope binding site for the tested allergens. [ABSTRACT FROM AUTHOR]

Background and purpose We try to search for specific serum or urinary biomarkers for the early detection, follow-up, and prediction of tumor recurrence, progression, and clinical outcome is a difficult task in individuals with bladder cancer. Materials and methods In this study, urinary samples were dialyzed to remove any interfering molecules and concentration by lyophilization. The urinary proteome maps of 10 healthy volunteers and 10 bladder transitional cell carcinoma (BTTC) patients were explored through two-dimensional polyacrylamide gel electrophoresis (2-D PAGE) coupled with mass spectrometry. With no fractionation, the proteome maps acquired in this study likely represented the total urinary proteins. Results Comparative proteomics indicated that six proteins were down-regulated and five proteins were up- regulated in BTCC patients as compared with normal. The down-regulated spots were identified as human haptoglobin precursor, human heparan sulfate proteoglycan perlecan, inter-alpha-trypsin inhibitor heavy chain H4 precursor, and AMBP protein precursor. The up-regulated spots were identified as peroxiredoxin 2, heparan sulfate proteoglycan perlecan, protease serine 1 fragment and AMBP protein precursor. Most of these de-regulated proteins were extracellular matrix–associated proteins, which may play roles in regulating the immune response, signal transduction and tumor invasions. Conclusion In this paper, 11 de-regulated proteins were observed in the urinary specimens of BTTC patients from the southwestern coast of Taiwan where Blackfoot disease is endemic and the unusually high incidence of BTTC in this area might attribute to high arsenic content in the drinking water. It is possible that long-term arsenic-induced alteration of these de-regulated proteins, most of which were extracellularmatrix – (ECM) related proteins which may play roles in regulating the immune response, signal transduction and tumor invasions, might be involved in BTTC development in southwestern Taiwan. [ABSTRACT FROM AUTHOR]

Introduction: New designer drugs of the amphetamine class like 4-methoxyamphetamine (PMA) and 4-methoxymethamphetamine (PMMA) elicit psychoactive effects in the central nervous system (CNS) by enhancing monoaminergic neurotransmission. These substances are substrates for neurotransmitter transporter proteins, and after binding with them they penetrate inside the cells. PMA and PMMA also reverse the transport of endogenic neurotransmitters and stimulate their increased release into the synaptic gap. PMMA has a weaker psychostimulating effect and a stronger hallucinogenic effect than PMA. Materials and methods: The article presents the case of fatal PMMA intoxication in a 28-year-old man. The post-mortem forensic toxicological analysis of collected blood samples was performed using the LC/MS/MS technique. The analysis detected 213 ng/mL of amphetamine, 270 ng/mL of 3,4-methylenedioxymethamphetamine (MDMA, Ecstasy), and 4585 ng/mL of PMMA. Results: The cause of death was acute multiple organ failure resulting from heavy intoxication with psychoactive substances, particularly with PMMA. [ABSTRACT FROM AUTHOR]

In the year 2008, 166 apple, bean, carrot, cucumber, lettuce, pear, potato and spinach samples from Slovene producers were analysed for plant protection product residues. The samples were analysed for the presence of 158 different active compounds using three analytical methods. In two samples (1.2%) exceeded maximum residue levels (MRLs) were determined which is better than the results of the monitoring of pesticide residues in the products of plant origin in the 27 European Union, Member States (EU MS) and 2 European Free Trade Association (EFTA) States: Norway and Iceland in 2008 (2.2%). The most frequently found active substance in agricultural products was dithiocarbamates. Products which contained 4 or more active substances per sample were apples and pears.

Chronic alcohol consumption is associated with fatty liver disease in mammals. The object of this study was to gain an understanding of dysregulated lipid metabolism in alcohol-fed C57BL/6 mice using a targeted lipidomic approach. Liquid chromatography tandem mass spectrometry was used to analyze several lipid classes, including free fatty acids, fatty acyl-CoAs, fatty acid ethyl esters, sphingolipids, ceramides, and endocannabinoids, in plasma and liver samples from control and alcohol-fed mice. The interpretation of lipidomic data was augmented by gene expression analyses for important metabolic enzymes in the lipid pathways studied. Alcohol feeding was associated with i) increased hepatic free fatty acid levels and decreased fatty acyl-CoA levels associated with decreased mitochondrial fatty acid oxidation and decreased fatty acyl-CoA synthesis, respectively; ii) increased hepatic ceramide levels associated with higher levels of the precursor molecules sphingosine and sphinganine; and iii) increased hepatic levels of the endocannabinoid anandamide associated with decreased expression of its catabolic enzyme fatty acid amide hydrolase. The unique combination of lipidomic and gene expression analyses allows for a better mechanistic understanding of dysregulated lipid metabolism in the development of alcoholic fatty liver disease.

Diarrhetic shellfish toxins (DSTs) are a group of phycotoxins that include okadaic acid (OA)/dinophysistoxin (DTX) analogues. At present, detailed data on the distribution of DST is insufficient, and studies of the appropriate sample sizes are lacking. This study investigated the DST frequency distribution in scallops and mussels by liquid chromatography-tandem mass spectrometry (LC/MS/MS) and a resampling analysis of existing data was carried out. The DST population-interval and the necessary sample size were also estimated. DSTs are localized in the scallop digestive-gland, and the DST concentrations in scallops were water-depth-dependent. DST concentrations in scallops and mussels showed normal distributions, but mussels tended to contain more DSTs than scallops. In the statistical resampling analysis of the acquired data on scallops and mussels, especially that using the bootstrap method, sample size was difficult to estimate when the DST variation was large. Although the DST population-interval could be statistically estimated from the sample standard deviation of three samples, the sample size corresponded to the risk management level, and the use of 13 or more samples was preferable. The statistical methods used here to analyze individual contents and estimate population content-intervals could be applied in various situations and for shellfish toxins other than DSTs.

Bacterial resistance to antibiotics and the disruption of beneficial microbiota are key problems in contemporary medicine and make the search for new, more efficient infection treatment strategies among the most important tasks in medicine. Multicomponent plant-derived preparations with mild antibacterial activity created by many simultaneous mechanisms together with anti-inflammatory, innate immune and regenerative capacity-stimulating properties are good candidates for this therapy, and proanthocyanidins are among the most promising compounds of this sort. In this study, we have isolated proanthocyanidins from Pelargonium sidoides DC root extract and characterized and compared the composition, antioxidant properties and antibacterial activity of the proanthocyanidin fraction with those of the whole extract. The results revealed that proanthocyanidins had significantly stronger antioxidant capacity compared to the root extract and exhibited a unique antibacterial action profile that selectively targets Gram-negative keystone periodontal and peri-implant pathogenic strains, such as Porphyromonas gingivalis, while preserving the viability of beneficial oral commensal Streptococcus salivarius. The finding suggests that proanthocyanidins from Pelargonium sidoides root extract are good candidates for the prolonged and harmless treatment of infectious diseases.

Tetrodotoxin (TTX) and its deoxy analogs, 5-deoxyTTX, 11-deoxyTTX, 6,11-dideoxyTTX, and 5,6,11-trideoxyTTX, were quantified in the tissues of three female and three male specimens of the marine puffer fish, Fugu niphobles, from the southern coast of Korea, and in the whole body of the brackishwater puffer fishes, Tetraodon nigroviridis (12 specimens) and Tetrodon biocellatus (three specimens) from Southeast Asia using LC/MS in single ion mode (SIM). Identification of these four deoxy analogs in the ovarian tissue of F. niphobles were further confirmed by LC/MS/MS. TTX and 5,6,11-trideoxyTTX were detected in all three puffer fish species as the major TTX analogs, similar to Japanese Fugu pardalis. While 6,11-dideoxyTTX was also found to be a major analog in almost all tissues of Korean F. niphobles, this analog was minor in the two Tetraodon species and Japanese F. pardalis. Among the tissues of F. niphobles, the concentrations of TTXs were highest in the ovaries (female) and skin (female and male).

The incidence rate of atrial fibrillation (AF) has stayed at a high level in recent years. Despite the intensive efforts to study the pathologic changes of AF, the molecular mechanism of disease development remains unclarified. Microproteins are ribosomally translated gene products from small open reading frames (sORFs) and are found to play crucial biological functions, while remain rare attention and indistinct in AF study. In this work, we recruited 65 AF patients and 65 healthy subjects for microproteomic profiling. By differential analysis and cross-validation between independent datasets, a total of 4 microproteins were identified as significantly different, including 3 annotated ones and 1 novel one. Additionally, we established a diagnostic model with either microproteins or global proteins by machine learning methods and found the model with microproteins achieved comparable and excellent performance as that with global proteins. Our results confirmed the abnormal expression of microproteins in AF and may provide new perspectives on the mechanism study of AF.

Cyclotrichium niveum (Boiss.) Manden & Scheng belonging to the Lamiaceae family, which is an endemic species in the eastern Anatolian region of Turkey, has an important place in terms of ethno-botany. The phytochemical composition of the plant, inhibition of acetylcholinesterase (AChE) (which hydrolyzes the neurotransmitter acetylcholine), inhibition of paraoxonase for antiatherosclerotic activity (hPON 1) (which detoxifies organophosphates), and antioxidant capacity were all investigated in this study. Phytochemical content was determined by LC/MS/MS, and enzyme inhibition and antioxidant capacity studies were determined by spectrophotometer. Antioxidant capacity of C. niveum extracts (methanol, hexane, and water) was determined by applying ABTS⋅ + , DPPH⋅, FRAP, and CUPRAC methods. Both the water and the methanol extracts of the C. niveum exhibited significant inhibition on the AChE (IC 50 value for methanol and water extract 0.114±0.14 mg/mL (R2:0.997) and 0.178±0.12 mg/mL (R 2 : 0.994), respectively). In contrast, the methanol and water extracts of the C. niveum did not exhibit the inhibition effect on hPON 1. The highest activity for ABTS⋅ + was 66.53 % in the water extract, and DPPH⋅ was 55.03 % in the methanol extract. In the metal-reducing power assay, the absorbance was 0.168±0.04 for FRAP water extract and 0.621±0.01 for CUPRAC methanol extract. According to LC/MS/MS analyses, hydroxybenzoic acid, salicylic acid, syringic acid, acetohydroxamic acid and luteolin determined in the plant extract. As a consequence, C. niveum which has antioxidant, anti-atherogenic and anti-neurodegenerative properties has the potential to be used as a natural medication instead of synthetic drugs used in Alzheimer's patients., (© 2023 Wiley-VHCA AG, Zurich, Switzerland.)

Objective: The compatibility of Eucommia ulmoides (Eu) and Psoralea corylifolia (Pc) on the pharmacokinetic (PK) properties in the rat was explored in this study., Methods: Eu extract, Pc extract and the combined extracts (crude drug ratio was 2:1) was administered by gavage, respectively. Two PK experiments were conducted. In first one, the blood samples were collected via the occuli chorioideae vein to get the PK properties of the components. In second one, the blood samples were simultaneously collected via the internal jugular vein or portal vein at different time points and the concentrations of target ingredients were detected by LC/MS/MS to clear the location where the interaction of Eu and Pc took place in vivo ., Results: Eight of 11 ingredients in Eu and Pc extract were determined in rat plasma. The exposure levels of geniposidic acid (GPA), aucubin (AU), geniposide (GP), pinoresinol diglucoside (PDG), psoralen glycosides (PLG) and isopsoralen glycosides (IPLG) were decreased 1/5-2/3 after administration of combined extracts. Comparing to the combined administration, the exposure of GPA and AU in plasma of single Eu administration collected via the portal vein were decreased 1/3-2/3, and the values of AUC 0-24h and AUC 0-∞ of GP collected from the portal vein or internal jugular vein were double increased. The other components' parameters were not significantly changed., Conclusion: In summary, the Pc and Eu combined administration could affect the exposure of the main components of Eu extract in rats due to the changed intestinal absorption. The research on the compatibility of Pc and Eu was helpful to guide the clinical administration of Eu and Pc simultaneously., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2022 Tianjin Press of Chinese Herbal Medicines. Published by ELSEVIER B.V.)

To determine 15 bile acid metabolic products in human serum by liquid chromatography-tandem mass spectrometry (LC/MS/MS) and value their diagnostic outcome in primary biliary cholangitis (PBC). Serum from 20 healthy controls and 26 patients with PBC were collected and went LC/MS/MS analysis of 15 bile acid metabolic products. The test results were analyzed by bile acid metabolomics, and the potential biomarkers were screened and their diagnostic performance was judged by statistical methods such as principal component and partial least squares discriminant analysis and area under curve (AUC). 8 differential metabolites can be screened out: Deoxycholic acid (DCA), Glycine deoxycholic acid (GDCA), Lithocholic acid (LCA), Glycine ursodeoxycholic acid (GUDCA), Taurolithocholic acid (TLCA), Tauroursodeoxycholic acid (TUDCA), Taurodeoxycholic acid (TDCA), Glycine chenodeoxycholic acid (GCDCA). The performance of the biomarkers was evaluated by the AUC, specificity and sensitivity. In conclusion, DCA, GDCA, LCA, GUDCA, TLCA, TUDCA, TDCA and GCDCA were identified as eight potential biomarkers to distinguish between healthy people and PBC patients by multivariate statistical analysis, which provided reliable experimental basis for clinical practice., (© 2023 Wiley-VHCA AG, Zurich, Switzerland.)

Diverse species of cyanobacteria have recently been discovered to produce theneurotoxic non-protein amino acid β-methylamino-L-alanine (BMAA). In Guam, BMAAhas been studied as a possible environmental toxin in the diets of indigenous Chamorropeople known to have high levels of Amyotrophic Lateral Sclerosis/ ParkinsonismDementia Complex (ALS/PDC). BMAA has been found to accumulate in brain tissues ofpatients with progressive neurodegenerative illness in North America. In Guam, BMAAwas found to be produced by endosymbiotic cyanobacteria of the genus Nostoc which livein specialized cycad roots. We here report detection of BMAA in laboratory cultures of afree-living marine species of Nostoc. We successfully detected BMAA in this marinespecies of Nostoc with five different methods: HPLC-FD, UPLC-UV, Amino AcidAnalyzer, LC/MS, and Triple Quadrupole LC/MS/MS. This consensus of five differentanalytical methods unequivocally demonstrates the presence of BMAA in this marinecyanobacterium. Since protein-associated BMAA can accumulate in increasing levelswithin food chains, it is possible that biomagnification of BMAA could occur in marineecosystems similar to the biomagnification of BMAA in terrestrial ecosystems. Productionof BMAA by marine cyanobacteria may represent another route of human exposure toBMAA. Since BMAA at low concentrations causes the death of motor neurons, low levelsof BMAA exposure may trigger motor neuron disease in genetically vulnerableindividuals.

Urinary hippuric acid (HA) and phenylacetylglycine (PAG) are biomarker candidates for drug-induced phospholipidosis (PLD). To confirm their utility in preclinical and clinical settings, it is essential to develop and validate their quantification method in advance. In this study, we have applied liquid chromatography-tandem mass spectrometry (LC/MS/MS) for simultaneous quantification of HA and PAG in rat urine, and matrix based ion suppression was assessed by post-column infusion assay. Effective sample dilution reduced matrix effect of urine to be negligible level and calibration curves showed good correlation between those in urine diluent and buffer alone. Reliability of this assay was confirmed by the assessments for intra- and inter-day precisions and accuracies of quality control samples. The method was applied to rat urine after multiple oral administrations of PLD-inducing drugs, and the changes in HA and PAG concentrations and their ratio were successfully detected as rat plasma in previous report. This is the first report to quantify HA and PAG easily and accurately as potential biomarkers to monitor PLD status. This assay would be useful tool for monitoring PLD in toxicological studies by non-invasive sampling. [ABSTRACT FROM AUTHOR]

In this study, we used liquid chromatography coupled to ion trap mass spectrometry (MS) for the quantification of 11 organosulfur compounds and analysis of their compositional changes in garlic during fermentation using 3 different microbe strains. The calibration curves of all 11 analytes exhibited good linearity (R ⩾ 0.995), and the mean recoveries measured at three concentrations were greater than 81.63% with relative standard deviations of less than 12.79%. Investigation of the compositional changes revealed that the γ-glutamyl peptides content in fermented blanched garlic reduced, whereas the content of the compounds in biosynthesis of S-allyl- l -cysteines from γ-glutamyl peptides increased significantly. Our results also indicated that starter cultures can be used selectively in the production of fermented garlic to increase the amounts of the desired organosulfur compounds. [ABSTRACT FROM AUTHOR]

A single-run analytical method was developed to analyze the three herbicides azimsulfuron, bensulfuron-methyl, and mesotrione and its metabolite (4-methylsulfonyl-2-nitrobenzoic acid (MNBA)) in brown rice and rice straw using liquid chromatography-tandem mass spectrometry (LC/MS/MS). Samples extracted using various versions of Quick, Easy, Cheap, Effective, Rugged, and Safe “QuEChERS” (original unbuffered, acetate (AOAC), and citrate (EN) buffered) methods gave poor recoveries of all the tested analytes in both matrices. The extraction efficiency was improved when primary-secondary amine (PSA) sorbent was removed from the purification step, with the best recovery being achieved for EN-QuEChERS, which was subsequently used throughout the study. Overall, a determination coefficients ( R 2 ) ⩾ 0.995 was achieved at matrix-matched calibration curves at various concentration ranges. The recovery rates at three fortification levels (limit of quantification (LOQ), 1/2 maximum residue limit (1/2MRL), and MRL) ranged from 78 to 114.5, with relative standard deviations (RSDs) < 18% for all the tested analytes in both matrices. The LOQs for all herbicides were lower than the MRL set by the Ministry of Food and Drug Safety (MFDS), Republic of Korea. Field trials with the recommended, or double the recommended dose, revealed that the herbicides can safely be applied to rice, as no residues were detected in the harvested samples at 110 days. [ABSTRACT FROM AUTHOR]

We established and validated a specific and sensitive analytical method for the determination of 1-vinyl-2-pyrrolidone (VP) as 1-vinyl-2-pyrrolidone-mercapturic acid (VPMA) in urine using an electrospray liquid chromatography tandem mass spectrometry (ESI-LC/MS/MS) column switching method. An online solid phase extraction (SPE) for sample cleanup was performed by column switching to a restricted access material and back-flushing to the analytical column. A Phenomenex Luna C8 column was used for sample separation (150 mm; ID 4,6 mm; 3 μm). D4-VPMA served as an isotope labeled internal standard and was detected in negative multiple-reaction monitoring (MRM) mode. The Limit of quantification (LOQ) for VPMA was 1.5 μg/L, the intra-day precision of three concentrations (2 μg/L, 75 μg/L and 400 μg/L) of spiked urine samples ranged from 2.7 to 7.3%, the inter-day precision from 3.4 to 14.4%. The accuracy ranged from 6.2 to 9.0%, for the intra-day experiments and from 0.3 to 6.9% for the inter-day experiments. The method was applied to urines of Sprague-Dawley rats exposed to VP as a proof of principle of VPMA as a potential biomarker. [ABSTRACT FROM AUTHOR]

Liquid chromatography-isotope dilution mass spectrometry (LC-IDMS) with formic acid hydrolysis was established for the accurate quantification of λDNA. The over-decomposition of nucleobases in formic acid hydrolysis was restricted by optimizing the reaction temperature and the reaction time, and accurately corrected by using deoxynucleotides (dNMPs) and isotope-labeled dNMPs as the calibrator and the internal standard, respectively. The present method could quantify λDNA with an expanded uncertainty of 4.6% using 10 fmol of λDNA. The analytical results obtained with the present method were validated by comparing with the results of phosphate-base quantification by inductively coupled plasma-mass spectrometry (ICP-MS). The results showed good agreement with each other. We conclude that the formic acid hydrolysis/LC-IDMS method can quantify λDNA accurately and is promising as the primary method for the certification of DNA as reference material. [ABSTRACT FROM AUTHOR]

In the present study quantification of phenolic components of Achyranthes aspera and Aerva javanica leaves was made using LC-ESI-MS/MS. Antioxidant and antimutagenic activities of both plant leaves' extracts probably associated with their phenolic constituents were also monitored. Extracts were prepared using different concentrations of aqueous and acidified methanol. Extract yields and total phenols varied 5.4–58.8% (w/w) and 111.2 ± 1.2 to 325.5 ± 2.9 mg g − 1 of extract, respectively. Achyranthes aspera having lesser cytotoxicity (2.95 ± 0.14% at 0.5 mg mL − 1 ) than that of Aerva javanica (12.2 ± 0.85% at 0.5 mg mL − 1 ) provided relatively good protection against oxidative damage to pBR322 DNA plasmid. LC-ESI-MS/MS profiling exposed sixteen phenolics including kaempferol, catechin, syringic, quinic, sinapic, caffeic, chlorogenic acids in Achyranthes aspera ; and six compounds including p-coumaric, gallic acid, myricetin in Aerva javanica . Aside from quinic acid, the two species did not share any phenolic compound. [ABSTRACT FROM AUTHOR]

Aloe-emodin, a natural polyphenolic anthraquinone, has shown various beneficial bioactivities in vitro. The aim of this study was to investigate the pharmacokinetics and metabolism of aloe-emodin. Aloe-emodin was intravenously and orally administered to rats. The concentrations of aloe-emodin and rhein, a metabolite of aloe-emodin, were determined by HPLC method prior to and after hydrolysis with β-glucuronidase and sulfatase/ β-glucuronidase. The results showed that the systemic exposures of aloe-emodin and its metabolites were ranked as aloe-emodin glucuronides (G) > rhein sulfates (S) > aloe-emodin > rhein and rhein G when aloe-emodin was given intravenously. In contrast, when aloe-emodin was administered orally, the parent form of aloe-emodin was not absorbed per se, and the systemic exposures of its metabolites were ranked as aloe-emodin G > rhein G > rhein. In conclusion, the metabolites of aloe-emodin are more important than the parent form for the bioactivities in vivo. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Comprehensive profiling of sphingolipids is of great importance for clinical and pharmaceutical studies. An LC/MS/MS method was established for the simultaneous separation and quantification of individual sphingolipid species including ceramides, dihydroceramides, glucosylceramides, sphingosine, sphingosine-1-phosphate, sphinganine and sphinganine-1-phosphate. All target individual sphingolipid species were separated and quantified in a single chromatographic run of <20 min. Method validation results indicated that calibration curves were linear in the range of 2.5–10,000 nM for ceramides and glucosylceramides, 10–10,000 nM for dihydroceramides, 5–10,000 nM for sphingosine, sphingosine-1-phosphate, sphinganine and sphinganine-1-phosphate, respectively. The limits of detection ranged from 0.5 nM to 5 nM. Accuracies of 92.5–113% with precisions of 0.3–8.0% RSD were obtained for all of the standards over a wide range of concentrations. The application of this method was demonstrated using B cells collected from Chronic Lymphocytic Leukemia patients (n = 5) and healthy donors (n = 4). 17 sphingolipid species were successfully characterized and quantified in the lipid extract. This is a rapid method that could be readily adapted to lipidomic investigations of sphingolipids in other bio-fluids and tissues. [ABSTRACT FROM AUTHOR]

An unknown impurity was observed during stability studies of Gabapentin capsules. This impurity has been identified, synthesized, isolated and characterized using modern analytical tool. The novel impurity was confirmed as adduct of Gabapentin and lactose; an excipient used in formulation. The elucidated impurity was further confirmed by its synthesis, which was formed due to Maillard reaction and Amadori rearrangement. [ABSTRACT FROM AUTHOR]

Piperine (PIP), the major alkaloid component from Piper longum L. and Piper nigrum L., could enhance the bioavailabilities of other drugs including rosuvastatin, peurarin and docetaxel (DOX) via inhibition of CYP3A and P -glycoprotein activity. Nevertheless, the effect of such drug combination usage on the in vivo exposure of PIP has not been investigated due to lack of assay for the simultaneous determination of PIP and other drugs such as DOX. Besides, the reported pharmacokinetics of PIP varied a lot without appropriate bioavailability determined from the same dose. In the current study, an LC/MS/MS method has been developed to simultaneously determine the plasma concentrations of PIP and DOX and further applied to investigate the pharmacokinetics properties of PIP after oral and intravenous administrations as well as the pharmacokinetics interactions between PIP and DOX after their co-administration. A simple protein precipitation method was employed for plasma sample treatment by adding a mixture of methanol and acetonitrile (1:1, v/v ) with glibenclamide as internal standard (IS). The LC/MS/MS system consisted of Agilent 6430 series LC pumps and auto-sampler. The chromatographic separation was carried out in 15 min on a Waters C 18 column (150 × 3.9 mm i.d., 4 μm) with a mobile phase containing 0.2% formic acid and acetonitrile (1:1, v/v ) at a flow rate of 0.4 ml/min. The detection was performed using the positive ion electrospray ionization (ESI) in multiple reaction monitoring (MRM) mode with precursor-to-product ion transitions at m / z 286.1 → 201.1 for PIP, m / z 830.3 → 548.9 for DOX and m / z 494.2 → 369.0 for IS. The method demonstrated good linearity for both PIP and DOX over the concentration range of 2.5–1280 ng/ml with LLOD at 2.5 ng/ml. The intra-day and inter-day precisions were less than 13.34% and relative error (R.E.) representing accuracy was in the range of −11.38 to 3.15%. The recoveries of PIP, DOX and IS were above 75% and there was no matrix effect. PIP and DOX exhibited good stabilities under various conditions. PIP was administrated via intravenous bolus at 3.5 mg/kg and via oral administration at 35 mg/kg and 3.5 mg/kg, while DOX was intravenously administrated at 7 mg/kg to Sprague-Daley rats. The plasma concentrations of PIP and DOX were determined using the above developed and validated method. At the dose of 3.5 mg/kg, the bioavailability of PIP was calculated to be 25.36%. Its AUC 0 → t was unproportionally increased with doses, indicating a potential non-linear pharmacokinetics profile of PIP. It was found that the AUC 0 → t and C 0 of DOX and t 1/2 of PIP were significantly increased after their combination use, suggesting potential enhanced bioavailability of not only DOX but also PIP, which may lead to the overall enhanced pharmacological effects. [ABSTRACT FROM AUTHOR]

The role of water quality and the preservation of aquatic environments are highly important for sustainability, with special reference to the ecosystems' supply and preservation. Pesticides are pollutants that generate significant impacts on the environment, some of which are not totally known. Current research assesses water and sediment samples from the river Piquiri in a region featuring high production of wheat, soybean and corn in the state of Paraná, Brazil. In fact, the river Piquiri is directly affected by pesticides from the surrounding fields. Water samples were extracted with a mixture of hexane : dichloromethane and the sediment samples were extracted with a mixture of acetone : hexane. Extracts were analyzed in LC/MS/ MS and the presence of herbicides and fungicides used in the region under analysis was confirmed. Results of water samples revealed the herbicide atrazine (0.030 µg L-1) and the fungicide Carbendazim (0,178 µg L-1). The fungicides Carbendazim (26.8 µg L-1) and Azoxistrobina (0.712 µg L-1) had the highest rates in the sediments in the third harvest at collection site 3. Results confirm herbicide and fungicide residues in the water and sediment of the river Piquiri even though concentrations do not compromise water drinkability due to rates below the permitted maximum rate. [ABSTRACT FROM AUTHOR]

The effects of various washing procedures, including stagnant, running, and stagnant and running tap water, and the use of washing solutions and additives, namely NaCl (1% and 2%), vinegar (2%, 5%, and 10%), detergent (0.5% and 1%), and charcoal (1% and 2%), on the reduction rate of diethofencarb were estimated in field-incurred crown daisy, a model of leafy vegetables, grown under greenhouses located in 3 different areas (Gwangju, Naju, and Muan). The original Quick, Easy, Cheap, Effective, Rugged, and Safe “QuEChERS” method was modified for extraction and liquid chromatography–tandem mass spectrometry (LC/MS/MS) was used for analysis. The recovery of diethofencarb in unwashed and washed samples was satisfactory and ranged between 84.28% and 115.32% with relative standard deviations (RSDs) of <6%. The residual levels decreased following washing with stagnant, running, and stagnant + running tap water (i.e., decline in levels increased from 65.08% to 85.02%, 69.99 to 86.79, and 74.75 to 88.96, respectively). The percentage of decline increased and ranged from 77.46% to 91.19% following washing with various solutions. Application of 1% detergent was found to be the most effective washing method for reducing the residues in crown daisy. Additionally, washing with stagnant and running tap water or even stagnant water for 5 min might reduce the residue levels substantially, making the prepared food safe for human consumption. [ABSTRACT FROM AUTHOR]

The current study aims to investigate the pharmacokinetics and brain uptake of HIV-1 replication inhibitor DB213 via a developed LC/MS/MS analytical method. A sensitive, selective, accurate and reliable LC/MS/MS method for determination and quantification of DB213 in rat plasma and brain was developed and validated. A triple quadrupole mass spectrometer equipped with electrospray ionization (ESI) source was applied for the detection of DB213 and benzamidine (Internal Standard). The analytes were quantified by using multiple reaction monitoring (MRM) mode with m / z 333.4 → 86.1 and m / z 121.2 → 104 for DB213 and benzamidine respectively. Chromatographic separation of DB213 and benzamidine was achieved on a SunFire C 8 (4.6 × 250 mm, i.d. 5 μm) analytical column with gradient elution of a mobile phase consisted of acetonitrile and 20 mM ammonium formate buffer (containing 0.5% formic acid). The method achieved good linearity from 1.95 ∼ 1000 ng/ml ( r 2 = 0.999) in plasma and 0.98 ∼ 125 ng/ml ( r 2 = 0.999) in brain. The validated method was successfully applied to plasma pharmacokinetics (PK) and brain uptake of intravenous administration of DB213 water solution (1 mg/kg) to Sprague-Dawley rats. It was found that the area under the plasma concentration–time curve from 0 to 360 min (AUC 0→360 min ) was 184422.1 ± 42450.8 ng min/ml and the elimination half-life of DB213 after intravenous administration was 70.9 ± 16.1 min. In addition, DB213 has demonstrated a potential to cross the blood-brain barrier via intravenous administration with a brain tissue concentration of 11.3 ± 3.6 ng/g peaked at 30 min post-dosing. [ABSTRACT FROM AUTHOR]

The epigenetic and anti-cancer activities of the nucleoside analog DNA methyltransferase (DNMT) inhibitors decitabine (5-aza-2′-deoxycytidine, DAC), azacitidine, and guadecitabine are thought to require cellular uptake, metabolism to 5-aza-2′-deoxycytidine triphosphate, and incorporation into DNA. This genomic incorporation can then lead to trapping and degradation of DNMT enzymes, and ultimately, passive loss of DNA methylation. To facilitate measurement of critical exposure-response relationships of nucleoside analog DNMT inhibitors, a sensitive and reliable method was developed to simultaneously quantitate 5-aza-2′-deoxycytidine genomic incorporation and genomic 5-methylcytosine content using LC–MS/MS. Genomic DNA was extracted and digested into single nucleosides. Chromatographic separation was achieved with a Thermo Hyperpcarb porous graphite column (100 mm × 2.1 mm, 5 μm) and isocratic elution with a 10 mM ammonium acetate:acetonitrile with 0.1% formic acid (70:30, v/v) mobile phase over a 5 min total analytical run time. An AB Sciex 5500 triple quadrupole mass spectrometer operated in positive electrospray ionization mode was used for the detection of 5-aza-2′-deoxycytidine, 2′-deoxycytidine, and 5-methyl-2′-deoxycytidine. The assay range was 2–400 ng/mL for 5-aza-2′-deoxycytidine, 50–10,000 ng/mL for 2′-deoxycytidine, and was 5–1000 ng/mL for 5-methyl-2′-deoxycytidine. The assay proved to be accurate (93.0–102.2%) and precise (CV ≤ 6.3%) across all analytes. All analytes exhibited long-term frozen digest matrix stability at −70 °C for at least 117 days. The method was applied for the measurement of genomic 5-aza-2′-deoxycytidine and 5-methyl-2′-deoxycytidine content following exposure of in vitro cell culture and in vivo animal models to decitabine. [ABSTRACT FROM AUTHOR]

Pharmaceutically active compounds are taken up and accumulate in crops irrigated with treated wastewater. This raises the concern of chronic human exposure to pharmaceuticals via food consumption. Thus, there is a need to develop a reliable technique to detect and quantify pharmaceuticals at environmentally relevant concentrations in human biological matrices, particularly urine. In this study, we focus on carbamazepine, an antiepileptic drug and recalcitrant compound that is taken up by crops—making it an excellent model compound for this study. This paper presents a new analytical technique enabling quantification of trace concentrations of carbamazepine and its metabolites in the urine of individuals who have been environmentally exposed. Sample preparation included extraction with acetonitrile followed by clean-up through mixed-mode ion-exchange cartridges and analysis using LC/MS/MS. This technique, which was validated for a wide range of concentrations (5–2000 ng L −1 ), exhibits low limits of quantification (3.0–7.2 ng L −1 ), acceptable recovery levels (70–120%), and low relative standard deviation (<20%). Unlike currently available methods for the analysis of water or treated wastewater that require large volumes (up to 1 L), the new method uses only 10 mL of urine. Moreover, relative to available methods for carbamazepine detection in the urine of individuals who are chronically treated with this drug, the limit of quantification values with our method are six orders of magnitude lower. The newly developed method has been successfully applied for the quantification of carbamazepine and its metabolites in the urine of healthy people exposed to this pharmaceutical through their diet. Our analytical protocol can provide the scientific community and stakeholders with real data for risk assessments and the design of policies ensuring safe use of wastewater for crop irrigation. [ABSTRACT FROM AUTHOR]

Sumatriptan succinate (SS) is a 5-HT1 receptor agonist used in the treatment of migraine having poor bioavailability (15%) due to its extensive first-pass effect. The aim of this work was to prepare SS sublingual fast dissolving thin films (SFDTFs) allowing the drug to directly enter the systemic circulation and bypassing the first-pass metabolism. Plain thin films were prepared using solvent casting technique adopting 23 × 3 factorial design to study the effect of polymer and plasticizer type and concentration on mechanical properties andin vitrodisintegration time of the plain prepared films using Design-Expert®. Medicated films were prepared after addition of 35 mg SS to each of the two selected plain formulae (F6 and F7) having desirability values above 0.9 showing the values of: 0.038, 0.039 kgf/mm2and 156.24, 164.16% and 0.0248, 0.0240 kgf/mm2as tensile strength, percent elongation and elastic modulus, respectively. PVP K30 was efficient as crystallization inhibitor in retarding SS crystallization. Pharmacokinetic study of the optimum formula F7 (PVP K30:SS (1:1 w/w)) in healthy human volunteers using LC/MS/MS revealed a shortertmax(0.25 h) compared to Imitrex® tablet 25 mg (2 h) which is considered promising especially for the rapid relief of acute migraine attacks. [ABSTRACT FROM PUBLISHER]

Analysis of deoxynivalenol (DON) and its metabolites 3-acetyl and 15-acetyldeoxynivalenol (3-ADON and 15-ADON) in wheat flour samples by liquid chromatography–tandem mass spectrometry (LC/MS/MS) during 2011–2013 was conducted. [ 13 C 15 ]–DON was used as the internal standard to accomplish as accurate as possible quantitation. Of all wheat samples ( n = 672), 91.5% were positive for DON, at levels ranging from 2.4 to 1130 μg/kg, with a median value of 154 μg/kg. The DON derivatives (3-Ac-DON, 15-Ac-DON) were far less frequently found and at lower levels than DON. The probable daily intakes (PDI) of DON (0.49 in 2011; 0.86 in 2012; 0.56 in 2013, expressed as μg/kg body weight/day) were all within the PDI of 1.0 μg/kg of bw/day for DON set by Scientific Committee for Food (SCF) in 2002. Still, persistent monitoring of DON is important. [ABSTRACT FROM AUTHOR]

The mung bean ( Vigna radiata) is an important food crop with preventative effects against human diseases. The anti-allergic activities of mung bean sprouts of different lengths were evaluated by assaying in vivo antipruritic activity and in vitro hyaluronidase inhibitory effects. After 48 h of growth, sprouts were determined to have the best activity and extracted with petroleum (PeF), ethyl acetate (EaF), and n-butanol (nBF). The active EaF extracts were further assayed for in vivo effects on compound 48/80-induced mast cell degranulation and histamine release, as well as the anti-dinitrophenyl (DNP) IgE-induced passive cutaneous anaphylaxis (PCA) reaction. The main chemical constituents were further analyzed by UV spectrophotometry and high-performance liquid chromatography with tandem mass spectrometric detection (LC/MS/MS). EaF significantly protected against compound 48/80-induced mast cell degranulation and histamine release, and PCA. Flavonoids were determined to be the main contributors to the anti-allergic activity of the EaF extracts. [ABSTRACT FROM AUTHOR]

A rapid, sensitive and specific method for quantifying piracetam in human plasma using Piracetam d-8 as the internal standard (IS) is described. The analyte and the IS were extracted from plasma by one-step precipitation of protein using an acetonitrile (100%). The extracts were analyzed by high-performance liquid chromatography coupled with electrospray tandem mass spectrometry (HPLC-MS/MS). The method had a chromatographic run time of 3.8 min and a linear calibration curve over the range 0.5-50 µg/mL ( r > 0.99). This LC-MS-MS procedure was used to assess the bioavailability of two piracetam formulations: piracetam + l-carnitine (Piracar®; 270/330 mg tablet) and piracetam (Nootropil®; 800 mg tablet) in healthy volunteers of both sexes. The geometric means with corresponding 90% confidence interval (CI) for test/reference percentage ratios were 88.49% (90% CI = 81.19 - 96.46) for peak concentration/dose and 102.55% (90% CI = 100.62 - 104.51) for AUCinf/dose. The limit of quantitation of 0.5 µg/mL is well suited for pharmacokinetic studies in healthy volunteers. It was concluded that piracetam (Piracar®; 270/330 mg tablet) has a bioavailability equivalent to the piracetam (Nootropil®; 800 mg tablet) formulation with regard to both the rate and the extent of absorption. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Simvastatin is a lipid-lowering drug that is metabolized to its active metabolite simvastatin acid (SA). We developed and validated a sensitive liquid chromatography-tandem mass spectrometry (LC/MS/MS) method to quantitate SA in human plasma using a liquid-liquid extraction method with methanol. The protonated analytes generated in negative ion mode were monitored by multiple reaction monitoring. Using 500-mL plasma aliquots, SA was quantified in the range of 0.1-100 ng/mL. Calibration was performed by internal standardization with lovastatin acid, and regression curves were generated using a weighting factor of 1/x2. The linearity, precision, and accuracy of this assay for each compound were validated using quality control samples consisting of mixtures of SA (0.1, 0.5, 5, and 50 ng/mL) and plasma. The intra-batch accuracy was 95.3-107.8%, precision was -2.2% to -3.7%, and linearity (r2) was over 0.998 in the standard calibration range. The chromatographic running time was 3.0 min. This method sensitively and reliably measured SA concentrations in human plasma and was successfully used in clinical pharmacokinetic studies of simvastatin in healthy Korean adult male volunteers. [ABSTRACT FROM AUTHOR]

The degradation of boscalid (Bd) in an aqueous solution was studied using different oxidation systems, including the persulfate ion (PS), TiO 2 (UT), N-TiO 2 (NT) and mixtures of UT/PS and NT/PS under sunlight irradiation, in addition to using heat-activated (50 or 80 °C) PS ions. NT exhibited a higher percent Bd degradation than UT, which was explained by a higher surface area and a higher amount of anatase for NT. However, the NT/PS or UT/PS systems did not degrade Bd as much as PS alone under sunlight, which may be a result of interactions between the produced hydroxyl and sulfate radicals. Eventually, the highest Bd degradation was obtained by the activation of PS at 80 °C. However, the degradation of Bd by NT or UT in an aqueous solution containing MeOH was completely inhibited. MeOH is a scavenger for hydroxyl radicals, OH and the positive holes of activated catalysts. In addition, the PS system was influenced more than the UT/PS and NT/PS systems were in the presence of MeOH. This result can be explained by the facts that (i) MeOH scavenged more OH than SO 4 − , and (ii) more SO 4 − was present for the UT/PS and NT/PS systems than for the PS. Therefore, the NT/PS and UT/PS systems showed a higher percent Bd degradation in an aqueous solution containing MeOH than the PS system did. Eventually, an analysis of the Bd residues was carried out using LC/MS/MS, and the seven basic intermediates were identified. [ABSTRACT FROM AUTHOR]

Vonoprazan fumarate (TAK-438) is a potassium-competitive acid blocker which was approved in Japan for a treatment of acid-related diseases. In this study a simple and validated bioanalytical method, which can simultaneously determine vonoprazan (TAK-438F) and its four metabolites (M-I, M-II, M-III and M-IV-Sul) in human plasma, was developed. The method is based on protein precipitation and subsequent ultra-high performance liquid chromatography separation followed by tandem mass spectrometry detection. The mass spectrometric parameters for detection of TAK-438F, M-I, M-III and M-IV-Sul were modified from their optimum values in order to achieve a simultaneous quantification while retaining enough sensitivity and wide dynamic ranges for all the target analytes. The validity and robustness of the method was verified through a validation study as per the regulatory guidance on bioanalytical method validation. The calibration ranges are 0.1–100 ng/mL for TAK-438F and M-III, and 1–1000 ng/mL for M-I, M-II and M-IV-Sul using the 100 μL of human plasma. The total run time per sample is 5 min. The working solution for M-III was recommended to be prepared separately, especially for the long-term use, in order to avoid the instability of M-III in the mixed working solutions, which could cause the high consumption of reference standards. The established method was applied to clinical pharmacokinetic studies and concentrations of all the analytes in human plasma were successfully determined with high reproducibility ensured by incurred sample reanalysis, indicating the suitableness of the established method. [ABSTRACT FROM AUTHOR]