Chromatography-electrospray Ionization-tandem Mass Research Articles

In vivo localization and postmortem stability of benzo[a]pyrene-DNA adducts.

DNA adducts of carcinogenic polycyclic aromatic hydrocarbons (PAHs) play a critical role in the etiology of gastrointestinal tract cancers in humans and other species orally exposed to PAHs. Yet, the precise localization of PAH-DNA adducts in the gastrointestinal tract, and the long-term postmortem PAH-DNA adduct stability are unknown. To address these issues, the following experiment was performed. Mice were injected intraperitoneally with the PAH carcinogen benzo[a]pyrene (BP) and euthanized at 24 h. Tissues were harvested either at euthanasia (0 time), or after 4, 8, 12, 24, 48, and 168 hr (7 days) of storage at 4°C. Portions of mouse tissues were formalin-fixed, paraffin-embedded, and immunohistochemically (IHC) evaluated by incubation with r7,t8-dihydroxy-t-9,10-epoxy-7,8,9,10-tetrahydrobenzo[a]pyrene (BPDE)-DNA antiserum and H-scoring. The remaining tissues were frozen, and DNA was extracted and assayed for the r7,t8,t9-trihydroxy-c-10-(N 2 -deoxyguanosyl)-7,8,9,10-tetrahydrobenzo[a]pyrene (BPdG) adduct using two quantitative assays, the BPDE-DNA chemiluminescence immunoassay (CIA), and high-performance liquid chromatography electrospray ionization tandem mass spectrometry (HPLC-ES-MS/MS). By IHC, which required intact nuclei, BPdG adducts were visualized in forestomach basal cells, which included gastric stem cells, for up to 7 days. In proximal small intestine villus epithelium BPdG adducts were visualized for up to 12 hr. By BPDE-DNA CIA and HPLC-ES-MS/MS, both of which used DNA for analysis and correlated well (P= 0.0001), BPdG adducts were unchanged in small intestine, forestomach, and lung stored at 4°C for up to 7 days postmortem. In addition to localization of BPdG adducts, this study reveals the feasibility of examining PAH-DNA adduct formation in wildlife species living in colder climates. Environ. Mol. Mutagen. 61:216-223, 2020. © 2019 Wiley Periodicals, Inc.

Extraction of triazine herbicides in environmental water samples using alumina nanoparticles and determination of residues by LC–MS/MS

The alumina nanoparticles (Al2O3 NPs) prepared by sol-gel method by reaction of aluminum sulfate with ammonia was tested for their adsorption capacity in the extraction of pesticide residues in water. The synthesized nanoparticles (NPs) size was determined by X-ray Diffraction (XRD) and Transmission Electron Microscope (TEM). The surface morphology of NPs was described by Scanning Electron Microscope (SEM). The cartridges of solid phase extraction (SPE) were prepared by Al2O3 NPs and protected between two polytetrafluoroethylene (PTFE) frits. These cartridges are used in extraction of different types of pesticide residues (ametryn, prometryn, simazine, and simetryn) in water. The water samples were spiked and passed through the cartridges with aliquots of pesticides. Testing of the amounts of pesticides adsorbed on the cartridges. The impact of temperature, sample quantity, flow rate, pH and ionic strength on cartridge performance was verified. Results of fortified sample assessment were contrasted with information collected from commercially accessible C18 cartridges for sample volume. The Liquid Chromatography Electrospray Ionization Tandem Mass Spectroscopy (LC-ESI-MS/MS) method involves the simultaneous determination of four herbicides in multiple reactions monitoring (MRM) mode and the detection limit is 0.005–0.025 μg/mL and the quantification limit is 0.01 μg/mL.

An LC/ESI-MS/MS method to quantify the PI3K inhibitor GDC-0084 in human plasma and cerebrospinal fluid: Validation and clinical application.

A liquid chromatography electrospray ionization tandem mass spectrometry (LC/ESI-MS/MS) method was developed and validated to measure GDC-0084 in human plasma and cerebrospinal fluid (CSF). Reverse-phase chromatography with gradient elution was performed using a C18 column (50 × 2.0 mm, 3 μm). Solid-phase extraction of plasma and CSF was employed to give excellent recovery. MS detection was performed with positive ion screening in multiple reaction monitoring mode. The precursor to the product ions (Q1 → Q3) selected for GDC-0084 and GDC-0084-d6 were 383.2 → 353.2 and 389.2 → 353.2, respectively. A separate calibration curve was established for human plasma and CSF. Both calibration curves, ranging from 0.2 to 200 ng/mL, were linear and had acceptable intra- and inter-day precision and accuracy. The lower limit of quantitation and limit of detection for GDC-0084 in human plasma were 0.2 ng/mL (signal/noise ≥47) and 0.005 ng/mL (signal/noise ≥3.5), respectively, and for GDC-0084 in human CSF were 0.2 ng/mL (signal/noise ≥19.7) and 0.04 ng/mL (signal/noise ≥7.2). This method was successfully applied to analyze serial plasma samples obtained from children with diffuse intrinsic pontine gliomas and other midline gliomas who participated in pharmacokinetic studies as part of a phase I clinical trial of GDC-0084.

Comparative metabolomics reveals differences in flavonoid metabolites among different coloured buckwheat flowers

Flavonoids are the largest group of secondary metabolites, and they play important biological functions. Buckwheat, particularly its flowers, contains a considerable amount of flavonoids. However, only a few flavonoid metabolites have been identified to date, and differences in flavonoid metabolites between Tartary and common buckwheat flowers have not yet been reported. In the present study, one Tartary buckwheat variety with green flowers and three common buckwheat varieties with white, pink and red flowers were sampled. Flowers of red-flowered common buckwheat had the highest total flavonoid content, followed by Tartary buckwheat flowers. The flower extracts were analysed using ultra-performance liquid chromatography–electrospray ionisation–tandem mass spectrometry (UPLC–ESI–MS/MS), and a total of 188 flavonoid metabolites, including 53 flavones, 39 flavonols, 33 flavone C-glycosides, 24 flavanones, 18 anthocyanins, 11 isoflavones, 5 proanthocyanidins and 5 flavonolignans, were detected. Multivariate statistics revealed a distinct difference in the flavonoid metabolism between Tartary and common buckwheat flowers, and both of them had unique functional metabolites. For example, common buckwheat flowers were rich in luteolin and apigenin, whereas Tartary buckwheat flowers were rich in tricin. These results provide new information regarding the flavonoid metabolites of buckwheat flowers and offer important theoretical support for the exploitation of buckwheat flowers.

Parallel enrichment of polyphenols and phytosterols from Pinot noir grape seeds with molecularly imprinted polymers and analysis by capillary high-performance liquid chromatography electrospray ionisation tandem mass spectrometry

This investigation describes an integrated workflow for the parallel extraction and recovery of polyphenols and phytosterols from Pinot noir grape seeds. Using (E)-resveratrol and stigmasterol as exemplars, the approach employs two different molecular imprinted polymers in tandem for the extraction of these compounds and their subsequent analysis by capillary high-performance liquid chromatography (capHPLC) interfaced with electrospray ionisation tandem mass spectrometry (ESI MS/MS). Information on the selectivity of the solid-phase extraction processes was obtained through analysis of the binding behaviour of (E)-resveratrol- and stigmasterol-imprinted polymers using structurally similar polyphenols or phytosterols with the extent of binding determined from the capHPLC-ion trap ESI MS/MS data. This study documents with Pinot noir grape seed extracts and optimised solid-phase extraction protocols that the (E)-resveratrol-templated MIP enabled a very high recovery (99%) of the health-beneficial polyphenol (E)-resveratrol with co-purification of procyanidin and catechin/epicatechin. Further, the stigmasteryl-3-O-methacrylate-templated polymer resulted in high recovery (96%) of the phytosterol stigmasterol with co-purification of campesteryl glycoside. The results also demonstrate that rapid and high-resolution capHPLC-ESI MS/MS methods can be used as part of the work flow for selectivity optimisation and monitoring of the performance of MIPs intended for use in the solid-phase extraction of bioactive molecules with nutraceutical properties from agricultural waste streams.

Purification and identification of a novel antifungal protein from Bacillus subtilis XB-1.

This study aimed to characterize a powerful antifungal component from bacteria. Bacillus subtilis strain XB-1, which showed maximal inhibition of Monilinia fructicola, was isolated and identified, and an antifungal protein was obtained from it. Ammonium sulfate precipitation, ion exchange chromatography, and sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) were used to purify and identify the proteins secreted by B. subtilis XB-1. Analyses revealed that purified fraction V had the strongest antifungal effect, with the largest pathogen inhibition zone diameter of 4.15cm after 4days (P < 0.05). This fraction showed a single band with a molecular weight of approximately 43kDa in SDS-PAGE. Results from SDS-PAGE and liquid chromatography electrospray ionization tandem mass spectrometry analyses demonstrated that fraction V was likely a member of the chitosanase family. These results suggest that B. subtilis XB-1 and its antifungal protein may be useful in potential biocontrol applications.

In vitro-digested milk proteins: Evaluation of angiotensin-1-converting enzyme inhibitory and antioxidant activities, peptidomic profile, and mucin gene expression in HT29-MTX cells

Over the past decades, several studies investigated the health-promoting functions of milk peptides. However, to date many hurdles still exist regarding the widespread use of milk-derived bioactive peptides, as they may be degraded during gastrointestinal digestion. Thus, the aim of our study was to in vitro digest intact whey protein isolate (WPI) and casein proteins (CNP), mimicking in vivo digestion, to investigate their bioactive effects and to identify the potential peptides involved. Whey protein isolate and CNP were digested using a pepsin-pancreatin protocol and ultra-filtered (3-kDa cutoff membrane). A permeate (<3 kDa) and a retentate (>3 kDa) were obtained. Soy protein was included as a control (CTR). Angiotensin-1-converting enzyme inhibitory (ACE1-I) and antioxidant activity (AOX) were assessed and compared with those observed in undigested proteins and CTR. Furthermore, the permeate was characterized by nano-liquid chromatography electrospray ionization tandem mass spectrometry (LC-nano ESI MS/MS) using a shotgun peptidomic approach, and retentate was further digested with trypsin and analyzed by MS using a shotgun proteomic approach to identify potentially bioactive peptides. Further, the effects of WPI, CNP, and CTR retentate on cell metabolic activity and on mucus production (MUC5AC and MUC2 gene expression) were assessed in intestinal goblet HT29-MTX-E12 cells. Results showed that WPI permeate induced a significant ACE1-I inhibitory effect [49.2 ± 0.64% (SEM)] compared with undigested WPI, CNP permeate, and retentate or CTR permeate (10.40 ± 1.07%). A significant increase in AOX (1.58 ± 0.04 and 1.61 ± 0.02 µmol of trolox AOX equivalents per mg of protein, respectively) upon digestion was found in WPI. Potentially bioactive peptides associated with ACE1-I and antihypertensive effects were identified in WPI permeate and CNP retentate. At specific concentrations, WPI, CNP, and CTR retentate were able to stimulate metabolic activity in HT29-MTX-E12 cells. Expression of MUC5AC was increased by CNP retentate and unaltered by WPI retentate; MUC2 expression was significantly increased by 0.33 mg/g of CNP and reduced by 1.33 mg/g of CNP. Our results confirm that milk proteins may be rich sources of bioactive compounds, with the greatest beneficial potential of CNP at the intestinal goblet cell level.

Dose-dependent exposure profile and metabolic characterization of notoginsenoside R1 in rat plasma by ultra-fast liquid chromatography-electrospray ionization-tandem mass spectrometry.

Notoginsenoside R1 (NGR1 ), a diagnostic protopanaxatriol-type (ppt-type) saponin in Panax notoginseng, possesses potent biological activities including antithrombotic, anti-inflammatory, neuron protection and improvement of microcirculation, yet its pharmacokinetics and metabolic characterization as an individual compound remain unclear. The aim of this study was to investigate the exposure profile of NGR1 in rats after oral and intravenous administration and to explore the metabolic characterization of NGR1 . A simple and sensitive ultra-fast liquid chromatographic-tandem mass spectrometric method was developed and validated for the quantitative determination of NGR1 and its major metabolites, and for characterization of its metabolic profile in rat plasma. The blood samples were precipitated with methanol, quantified in a negative multiple reaction monitoring mode and analyzed within 6.0 min. Validation parameters (linearity, precision and accuracy, recovery and matrix effect, stability) were within acceptable ranges. After oral administration, NGR1 exhibited dose-independent exposure behaviors with t1/2 over 8.0 h and oral bioavailability of 0.25-0.29%. A total of seven metabolites were characterized, including two pairs of epimers, 20(R)-notoginsenoside R2 /20(S)-notoginsenoside R2 and 20(R)-ginsenoside Rh1 /20(S)-ginsenoside Rh1 , with the 20(R) form of saponins identified for the first time in rat plasma. Five deglycometabolites were quantitatively determined, among which 20(S)-notoginsenoside R2 , ginsenoside Rg1 , ginsenoside F1 and protopanaxatriol displayed relatively high exploration, which may partly explain the pharmacodynamic diversity of ginsenosides after oral dose.

Formation of Bulky DNA Adducts by Non-Enzymatic Production of 1,2-Naphthoquinone-Epoxide from 1,2-Naphthoquinone under Physiological Conditions.

Quinones may be formed metabolically or abiotically from environmental pollutants and polycyclic aromatic hydrocarbons (PAHs); many are recognized as toxicological intermediates that cause a variety of deleterious cellular effects including mutagenicity. The PAH-o-quinone, 1,2-naphthoquinone (1,2-NQ), may exert its genotoxic effects through interactions with cellular nucleophiles such as DNA, however, the mechanisms of 1,2-NQ adduct formation are still under investigation. With the aim to further understand these mechanisms, the chemical structures of adducts formed from the reaction of 2'-deoxyguanosine (dG) with 1,2-NQ under physiological conditions were investigated by liquid chromatography electrospray ionization tandem mass spectrometry and 1H NMR analyses. Results showed that 1,2-NQ underwent non-enzymatic oxidation to form a 1,2-NQ-epoxide which in turn formed at least four bulky adducts with dG, and these adducts were more likely to be formed under physiological conditions. A mechanism was proposed whereby hydration of 1,2-NQ to form unstable naphthohydroquinones and 2-hydroxy-1,4-naphthoquinone resulted in formation of hydrogen peroxide that oxidized 1,2-NQ. These results suggest that the genotoxicity of 1,2-NQ may not only be caused through oxidative DNA damage and adduct formation through Michael addition but also through non-enzymatic oxidative transformation of 1,2-NQ itself to form an intermediate PAH-epoxide which covalently binds to DNA.

Ziziphora taurica subsp. taurica: Analytical Characterization and Biological Activities.

The Lamiaceae family comprises many flowering plants classified into about 236 genera. The genus Ziziphora is one of the well-known genera of this family and its species are important in different fields of pharmaceutical, chemical, traditional, and folk medicines. The phytochemicals present in Ziziphora include monoterpenic essential oils, triterpenes, and phenolic substances. The aim of this paper was to study the phytochemical profile of Ziziphora taurica subsp. taurica and compare and evaluate the biological activities of its ethyl acetate (ZTT-EtOAc), methanolic (ZTT-MeOH), and aqueous (ZTT-W) extracts based on their enzyme inhibition and antioxidant capacities. Determination of total phenolic (TPC) and total flavonoid (TFC) contents as well as biological activities were determined using spectrophotometric procedures. Subsequently, the individual phenolic compounds were detected by liquid chromatography–electrospray ionization–tandem mass spectrometry (LC–ESI–MS/MS). In total, twenty-two different phenolic compounds were identified, including apigenin, ferulic acid, and luteolin which were the most common. ZTT-MeOH extract showed the best antioxidant activity, whereas ZTT-EtOAc extract was the most effective against tyrosinase and α-amylase. Ziziphora taurica subsp. taurica represents a potential source of natural compounds with positive effects on human health.

Lysophosphatidylcholine is a Major Component of Platelet Microvesicles Promoting Platelet Activation and Reporting Atherosclerotic Plaque Instability.

Microvesicles (MVs) are small cell-derived vesicles, which are mainly released by activated cells. They are part of a communication network delivering biomolecules, for example, inflammatory molecules, via the blood circulation to remote cells in the body. Platelet-derived MVs are known to induce vascular inflammation. Research on the mediators and mechanisms of their inflammatory effects has attracted major interest. We hypothesize that specific lipids are the mediators of vascular inflammation caused by platelet-derived MVs. Liquid chromatography electrospray ionization-tandem mass spectrometry was used for lipid profiling of platelet-derived MVs. Lysophosphatidylcholine (LPC) was found to be a major component of platelet-derived MVs. Investigating the direct effects of LPC, we found that it induces platelet activation, spreading, migration and aggregation as well as formation of inflammatory platelet-monocyte aggregates. We show for the first time that platelets express the LPC receptor G2AR, which mediates LPC-induced platelet activation. In a mouse model of atherosclerotic plaque instability/rupture, circulating LPC was detected as a surrogate marker of plaque instability. These findings were confirmed by matrix-assisted laser desorption ionization imaging, which showed that the LPC concentration of human plaques was highest in vulnerable plaque regions. LPC is a major component of platelet-derived MVs and via its interaction with G2AR on platelets contributes to platelet activation, spreading, migration and aggregation and ultimately to vascular inflammation. Circulating LPC reports on atherosclerotic plaque instability in mice and is significantly increased in unstable areas of atherosclerotic plaques in both mice and humans, linking LPC to plaque instability.

Reactive carbonyl compounds, carbonyl stress, and neuroinflammation in methyl alcohol intoxication

Methyl alcohol intoxications are characterized by high lethality and high prevalence of serious visual and brain damage in survivors. The mechanisms of toxic brain damage are complex and the role of carbonyl stress has not been studied yet. We measured the acute and follow-up concentrations of reactive carbonyl compounds in patients with acute methyl alcohol intoxication. Blood samples were collected from 28 subjects hospitalized with confirmed methyl alcohol intoxication and from 36 subjects who survived poisoning 2 years after discharge. Serum concentrations of C6–12 reactive aldehydes were measured by liquid chromatography–electrospray ionization–tandem mass spectrometry. The acute concentrations of all measured reactive aldehydes were higher than the follow-up concentrations: 36.4 ± 4.8 vs. 21.6 ± 5.2 ng cm−3 for C6; 38.9 ± 5 vs. 17.0 ± 2.0 ng cm−3 for C7; 18.8 ± 3.9 vs. 4 ± 0 cm−3 for C8; 36.5 ± 3.9 vs. 19.0 ± 3.0 ng cm−3 for C9; 6.1 ± 0.4 vs. 4.0 ± 0.5 ng cm−3 for C10; 13.6 ± 3.0 vs. 3.7 ± 0.6 ng cm−3 for C11; and 7.8 ± 0.4 vs. 4.7 ± 0.4 ng cm−3 for C12 (all p < 0.001). The patients who survived the intoxication had higher concentration of reactive carbonyl compounds than those who died: 38.6 ± 5.9 vs. 28.3 ± 1.7 ng cm−3 for C6 (p = 0.002); 20.7 ± 4.7 vs. 11.8 ± 1.2 ng cm−3 for C8 (p = 0.001); 37.7 ± 4.8 vs. 31.8 ± 3.8 ng cm−3 for C9 (p = 0.042); and 7.9 ± 0.6 vs. 7.3 ± 0.5 ng cm−3 for C12 (p = 0.022). A significant association was present between severity of metabolic acidosis, anion gap, and the acute concentration of measured biomarkers: r = − 0.39; p = 0.046 for C6; r = − 0.42; p = 0.035 for C7; r = − 0.48; p = 0.012 for C8; r = − 0.39; p = 0.046 for C9; and r = − 0.47; p = 0.015 for C11. The acute concentration of C6–C12 reactive aldehydes positively correlated with the acute serum concentration of leukotrienes (all p < 0.05). Acute elevation of serum concentration of reactive carbonyl compounds suggests that carbonyl stress is involved in the mechanisms of leukotriene-mediated neuroinflammatory response to methyl alcohol-induced toxic brain damage.

METHOD DEVELOPMENT AND VALIDATION FOR THE ESTIMATION OF AMPRENAVIR IN HUMAN PLASMA BY LIQUID CHROMATOGRAPHY–ELECTROSPRAY IONIZATION–TANDEM MASS SPECTROMETRY

Objective: The main aim of the present study was to develop a sensitive liquid chromatography–electrospray ionization–tandem mass spectrometric technique for the quantitation of amprenavir in human plasma.&#x0D; Methods: Chromatographic separation was achieved on a reversed-phase Symmetry C18 (50 mm×4.6 mm, 3.5 μm) column with isocratic elution by acetonitrile and 0.1% v/v formic acid in the ratio of 90:10 v/v as mobile phase. Chromatographic peaks were resolved with 0.7 ml/min flow rate. Drug was extracted with ethyl acetate solvent by liquid–liquid extraction method. Monitoring of transition of m/z 506.2 and 71.0 for amprenavir and 628 and 421 for methyl-indinavir was made on multiple reaction monitoring.&#x0D; Results: Calibration curve of amprenavir was linear over 1–600 ng/ml concentration range with regression coefficient (r2) value of &gt;0.99. The % relative standard deviation values were &lt;8.5% for interday and intraday precision and accuracy. The method has excellent recovery, and the percentage recovery values of lower quality control (QC), median QC, and higher QC samples were 101.86%, 102.8%, and 99.28%, respectively.&#x0D; Conclusion: The drug was stable for more time at variable stability conditions, and method was successfully applicable to regular analysis of amprenavir in biological matrices.

In vitro DNA/RNA Adductomics to Confirm DNA Damage Caused by Benzo[a]pyrene in the Hep G2 Cell Line.

In the development of new chemical substances, genetic toxicity evaluations are a high priority for safety risk management. Evaluation of the possibility of compound carcinogenicity with accuracy and at reasonable cost in the early stages of development by in vitro techniques is preferred. Currently, DNA damage-related in vitro genotoxicity tests are widely-used screening tools after which next generation toxicity testing may be applied to confirm DNA damage. DNA adductomics may be used to evaluate DNA damage in vitro, however confirmation of DNA adduct identities through comparison to authentic standards may be time-consuming and expensive processes. Considering this, a streamlined method for confirming putative DNA adducts that are detected by DNA adductomics may be useful. With this aim, in vitro DNA adductome methods in conjunction with in vitro RNA adductome methods may be proposed as a DNA adductome verification approach by which to eliminate false positive annotations. Such an approach was evaluated by conducting in vitro assays whereby Hep G2 cell lines that were exposed to or not exposed to benzo[a]pyrene were digested to their respective 2'-deoxynucleosides or ribonucleosides and analyzed by liquid chromatography electrospray ionization tandem mass spectrometry (LC/ESI-MS/MS) by comparative DNA and RNA adductomics through neutral loss targeting of the [M + H]+ > [M + H – 116]+ or [M + H]+ > [M + H −132]+ transitions over predetermined ranges. Comparisons of DNA adductome maps revealed putative DNA adducts that were detected in exposed cells but not in unexposed cells. Similarly, comparisons of RNA adductome maps revealed putative RNA adducts in exposed cells but not in unexposed cells. Taken together these experiments revealed that analogous forms of putative damage had occurred in both DNA and RNA which supported that putative DNA adducts detected by DNA adductomics were DNA adducts. High resolution mass spectrometry (HRMS) was utilized to confirm that putative nucleic acid adducts detected in both DNA and RNA were derived from benzo[a]pyrene exposure and these putative adducts were identified as 7,8-dihydroxy-9,10-epoxy-7,8,9,10-tetrahydrobenzo[a]pyrene- (B[a]PDE)-type adducts. Overall, this study demonstrates the usefulness of utilizing DNA/RNA adductomics to screen for nucleic acid damage.

Curcumin Combined with FOLFOX Chemotherapy Is Safe and Tolerable in Patients with Metastatic Colorectal Cancer in a Randomized Phase IIa Trial

ABSTRACTBackgroundCurcumin is the main active ingredient of the spice turmeric, investigated extensively for putative anticancer properties.ObjectivesThis phase IIa open-labelled randomized controlled trial aimed to assess safety, efficacy, quality of life, neurotoxicity, curcuminoids, and C-X-C-motif chemokine ligand 1 (CXCL1) in patients receiving folinic acid/5-fluorouracil/oxaliplatin chemotherapy (FOLFOX) compared with FOLFOX + 2 g oral curcumin/d (CUFOX).MethodsTwenty-eight patients aged >18 y with a histological diagnosis of metastatic colorectal cancer were randomly assigned (1:2) to receive either FOLFOX or CUFOX. Safety was assessed by Common Toxicity Criteria-Adverse Event reporting, and efficacy via progression-free survival (PFS) and overall survival (OS). Quality of life and neurotoxicity were assessed using questionnaires (European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-C30 and Functional Assessment of Cancer Treatment-Gynecologic Oncology Group-Neurotoxicity). Plasma curcuminoids were determined with liquid chromatography (LC) electrospray ionization tandem mass spectrometry and CXCL1 by ELISA.ResultsAddition of daily oral curcumin to FOLFOX chemotherapy was safe and tolerable (primary outcome). Similar adverse event profiles were observed for both arms. In the intention-to-treat population, the HR for PFS was 0.57 (95% CI: 0.24, 1.36; P = 0.2) (median of 171 and 291 d for FOLFOX and CUFOX, respectively) and for OS was 0.34 (95% CI: 0.14, 0.82; P = 0.02) (median of 200 and 502 d for FOLFOX and CUFOX, respectively). There was no significant difference between arms for quality of life (P = 0.248) or neurotoxicity (P = 0.223). Curcumin glucuronide was detectable at concentrations >1.00 pmol/mL in 15 of 18 patients receiving CUFOX. Curcumin did not significantly alter CXCL1 over time (P = 0.712).ConclusionCurcumin is a safe and tolerable adjunct to FOLFOX chemotherapy in patients with metastatic colorectal cancer. This trial was registered at clinicaltrials.gov as NCT01490996 and at www.clinicaltrialsregister.eu as EudraCT 2011-002289-19.

Development and Validation of HPLC–MS/MS Method for the Simultaneous Determination of 8-Hydroxy-2′-deoxyguanosine and Twelve Cosmetic Phenols in Human Urine

A simple and sensitive method based on liquid–liquid extraction (LLE) and liquid chromatography electrospray ionization tandem mass spectrometry (LC–ESI–MS/MS), was developed and validated for the simultaneous determination of 8-hydroxy-2′-deoxyguanosine and twelve cosmetic phenols, including five benzophenone (BP)-type ultraviolet (UV) filters, five parabens, bisphenol A (BPA) and triclosan (TCS) in human urine. Urine samples were treated by a combination of enzymatic deconjugation with β-glucuronidase/arylsulfatase and extraction with ethyl acetate. The efficiencies of different extraction procedures were investigated. Both chromatographic and mass spectrometric conditions were optimized. As a result, under the optimized conditions, the limits of detection (LODs) for the analytes in the range from 0.01 to 0.23 μg/L were achieved. The intra-day and inter-day precisions were within the range of 0.8–6.1% and 1.8–9.5% (relative standard deviation, RSD), respectively. The correlation coefficients (R2) and recoveries for the analytes were ranged from 0.991–0.999 and 80.0–108%, respectively. The developed method initially combines the simultaneous analysis of urinary 8-hydroxy-2′-deoxyguanosine, BP-type UV filters, parabens, BPA and TCS, and was successfully applied to urine samples from children in South China.

Pharmacokinetics of cligosiban in dog plasma after oral administration by liquid chromatography electrospray ionization tandem mass spectrometry

In this study, a simple and reliable liquid chromatography coupled with Q-Exactive-Orbitrap-MS was developed and validated for detecting and quantifying cligosiban and its metabolites in dog plasma after oral administration. The plasma samples were pretreated with acetonitrile and separated on a Diamonsil C18 column (4.6 × 100 mm, i.d. 3 μm) with 0.1% formic acid in water and acetonitrile as mobile phase. The method was validated according to the guidance of the US Food and Drug Administration. The assay was linear over the tested concentration ranges with coefficients of correlation >0.995. The extraction recovery was >83.23% with RSD <15%. Precision was <9.31% and accuracy ranged from -4.40 to 10.20%. The method was free of matrix effects. Under the conditions used, four metabolites were detected and their identities were identified by accurate masses and fragment ions. M1 and M3 were further confirmed by reference standards. The biotransformation pathways included demethylation and glucuronidation. The validated method was further applied to quantify cligosiban, M1 and M3 in dog plasma. After oral administration, cligosiban was detectable in dog plasma and reached the maximum concentration at ~1.67 ± 0.58 h post-dose. It was rapidly eliminated with a half-life of 3.48 ± 0.80 h. M1 showed high plasma exposure with its area under the curve being 23.31% of that of cligosiban.

Serotransferrin and C-type lectin could mediated NCC activity by interacting with NCCRP-1 in Nile tilapia (Oreochromis niloticus)

The alumina nanoparticles (Al2O3 NPs) prepared by sol-gel method by reaction of aluminum sulfate with ammonia was tested for their adsorption capacity in the extraction of pesticide residues in water. The synthesized nanoparticles (NPs) size was determined by X-ray Diffraction (XRD) and Transmission Electron Microscope (TEM). The surface morphology of NPs was described by Scanning Electron Microscope (SEM). The cartridges of solid phase extraction (SPE) were prepared by Al2O3 NPs and protected between two polytetrafluoroethylene (PTFE) frits. These cartridges are used in extraction of different types of pesticide residues (ametryn, prometryn, simazine, and simetryn) in water. The water samples were spiked and passed through the cartridges with aliquots of pesticides. Testing of the amounts of pesticides adsorbed on the cartridges. The impact of temperature, sample quantity, flow rate, pH and ionic strength on cartridge performance was verified. Results of fortified sample assessment were contrasted with information collected from commercially accessible C18 cartridges for sample volume. The Liquid Chromatography Electrospray Ionization Tandem Mass Spectroscopy (LC-ESI-MS/MS) method involves the simultaneous determination of four herbicides in multiple reactions monitoring (MRM) mode and the detection limit is 0.005–0.025 μg/mL and the quantification limit is 0.01 μg/mL.

Simultaneous quantification of five lignans from Schisandra chinensis in various tissues of rats

In this research study, a rapid, sensitive, and specific high-performance liquid chromatography–electrospray ionization–tandem mass spectrometry (HPLC–ESI–MS/MS) method was established and validated, in regard to the simultaneous quantification of five sedative and hypnotic lignans (schisandrin, schisandrol B, schisantherin A, deoxyschisandrin, and schisandrin B) in various tissues of rats (including heart, liver, spleen, lung, and kidney). The purpose of the study was to clarify the tissue distribution of the total lignans extract of Schisandra chinensis (SC). Then, the analytes were separated on a MERCK Purospher STAR LP C18 column (250 mm × 4.6 mm, 5 μm), with a mobile phase consisting of 0.05% (v/v) formic acid acetonitrile, and 0.05% (v/v) formic acid water, and a flow rate of 1 mL/min. All of the calibration curves of the five components showed good linearity (r &gt; 0.9950), with ranges of 4.8 to 1920 ng/mL for analytes. The intra-day and inter-day precisions (relative standard deviation [RSD] %) were within 13.76% for all of the analytes. The average recoveries of the five analytes were greater than 85.23%, and the mean value of the matrix effect ranged from 82.3% to 93.4%. The five analytes were confirmed to be stable during the storage, preparation, and analytic procedures. The major target tissues of the total lignans extract of the SC in the rats were the livers and kidneys.

Simultaneous Determination of Preservatives, Artificial Sweeteners, and Synthetic Dyes in Kimchi by Ultra-Performance Liquid Chromatography Electrospray Ionization Tandem Mass Spectrometry (UPLC-ESI-MS/MS)

A simple and rapid method was developed for the simultaneous determination of five preservatives, six artificial sweeteners, and nine synthetic dyes in kimchi using ultra-performance liquid chromatography electrospray ionization tandem mass spectrometry (UPLC-ESI-MS/MS) with multiple reaction monitoring (MRM). The chromatographic separation was performed in 5.5 min using an Acquity UPLC BEH C18 column (100 mm × 2.1 mm, 1.7 µm) with a mobile phase composed of 0.002% trifluoroacetic acid and 10 mM aqueous ammonium acetate or 9:1 (v/v) methanol:acetonitrile. Linear calibration curves were obtained with correlation coefficients above 0.98. The limits of quantification ranged between 0.227 and 8.569 ng/mL, while the recovery values in kimchi samples were from 83.1 to 113.5%. Forty kimchi samples were analyzed for the food additives, with sweeteners detected in more than half of these samples. The most commonly detected sweetener was saccharin, and six of the kimchi samples contained a combination of sweeteners; dulcin, sucralose, acesulfame K, preservatives, and synthetic dyes were not detected. Based on these results, the developed method can be used for the rapid quality control of food additives in kimchi.