Liquid Chromatography Quadrupole Time-of-flight Mass Spectrometry Research Articles

Effects of heat-reinforcing acupuncture on urine metabolites in rheumatoid arthritis rabbits

To compare the effects of different acupuncture methods on urine metabolites in rheumatoid arthritis (RA) rabbits, and to explore the specificity mechanism of heat-reinforcing acupuncture for RA. A total of 40 clean purple-blue rabbits were randomly allocated to a normal group, a model group, a mild reinforcing-reducing needling (MRRN) group, a twirling-reinforcing needling (TRN) group and a heat-reinforcing needling (HRN) group, 8 rabbits in each one. Except the normal group, the rabbits in the remaining groups were treated with ovalbumin and freezing to establish RA model. The rabbits in the MRRN group, TRN group and HRN group were treated with MRRN, TRN and HRN at "Zusanli" (ST 36), respectively, 30 min per treatment, once a day for seven days. After treatment, 24-h urine was collected. The rabbits were sacrificed to collect synovial tissues of knee to perform morphology observation; the liquid chromatography quadrupole time-of-flight mass spectrometry (LC-Q/TOF-MS) was applied to measure urine metabolites. All the data were analyzed by principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA). Compared with the normal group, the leucine-related metabolites, as main urine metabolites, were decreased in the model group (P<0.05), while the purine-related metabolites and tryptophane-related metabolites were increased (P<0.05). Compared with the model group, the leucine-related metabolites, as main urine metabolites, were increased in the three needling groups after treatment (P<0.05), while the tryptophan-related metabolites andpurine-related metabolites were decreased (P<0.05), moreover, the leucine-related metabolites in the HRN group were obviously higher than those in the MRRN group and TRN gruop (P<0.05). MRRN, TRN and HRN can regulate the pathway of leucine metabolism (energy metabolism), purine metabolism (oxidative damage) and tryptophane metabolism (immune regulation) for RA, The specificity of HRN for RA focuses on regulation of leucine metabolism (energy metabolism).

Effect of mixing different kinds of fruit juice with sour cherry puree on nutritional properties.

The main objective of this study was to investigate the effect of mixing sour cherry puree with apple, pear, quince and flowering quince juices on characteristics of 17 different products (12 smoothies and 5 semi-products). Compounds (phenolic compounds, vitamin C, sugar, pectin), antioxidant activity (ORAC, ABTS, FRAP), and physicochemical parameters (titratable acidity, soluble solids, viscosity, colour) of different products were evaluated. Depending on the type of product, 8 to 20 phenolic compounds, belonging to the anthocyanins, flavan-3-ols, flavonols, hydroxycinnamic acids, and dihydrochalcone, were identified by liquid chromatography/quadrupole time-of-flight mass spectrometry (LC/QTOF-MS). The highest content of polyphenols was observed in the sour cherry-flowering quince smoothie, while the lowest was observed in the sour cherry-pear smoothie. The study showed that the major polyphenols compounds in the smoothies were polymeric procyanidins, which were positively correlated with antioxidant activity. In addition, some kind of synergistic effect was observed between some compounds of sour cherry and flowering quince which could increase the antioxidant activity of the final product. The mixing of various fruit products could be interesting from a nutritional as well as commercial perspective.

Analysis of Phytochemicals in Petroleum Ether Leaves Extract from Abutilon Pannosum and Grewia Tenax by Liquid Chromatography/ Quadrupole Time-of-Flight Mass Spectrometry (LC/Q-TOF-MS) after Continuous Hot Percolation Successive Soxhlet Extraction

Analysis of Phytochemicals in Petroleum Ether Leaves Extract from Abutilon Pannosum and Grewia Tenax by Liquid Chromatography/ Quadrupole Time-of-Flight Mass Spectrometry (LC/Q-TOF-MS) after Continuous Hot Percolation Successive Soxhlet Extraction

Comparison of sample preparation strategies for target analysis of total thyroid hormones levels in serum by liquid chromatography-quadrupole time-of-flight-mass spectrometry

This paper describes a novel method based on liquid chromatography quadrupole time-of-flight-mass spectrometry (LC-QTOF-MS) for target analysis of total THs in serum. Several sample preparation strategies have been evaluated to reduce matrix effect (namely, HybridSPE cartridges, supported liquid extraction, SLE and solid phase extraction, SPE). Deproteinization and further clean-up with mixed-mode SPE was selected as the best strategy for sample preparation, since achieved the cleanest extracts and reduced ionization suppression effects (between −11 and −24%).Method validation was performed by the analysis of control human serum samples. Criteria for confirming THs identity in serum extracts were based on retention times, accurate masses, isotopic pattern and MS/MS fragmentation pattern. Moreover, the quantitation capabilities of the LC-QTOF-MS method were also evaluated in terms of linearity, precision, accuracy and sensitivity by the application of matrix-matched calibration.Additionally, the developed LC-QTOF-MS method successfully provides qualitative information on endogenous components responsible of ion suppression (e.g. lysophosphatidylcholines), via post acquisition data analysis. This demonstrates the significant advantage of using LC-QTOF-MS, as it allows retrospective querying of the acquired data without the need of re-injecting/re-processing the samples.

Identification of urinary metabolites with potential blood pressure-lowering effects in lentil-fed spontaneously hypertensive rats.

Urine samples were obtained from a previously completed study that showed lentil consumption attenuates the increase in blood pressure that occurs over time in spontaneously hypertensive rats (SHRs). The objective of the present study was to compare the metabolite profile of the urine samples from control and lentil-fed SHR in relation to the compounds present in lentils but not in other pulses. The urine samples were from 17-week-old, male SHR fed semi-purified diet prepared with powder (30%, w/w) from cooked whole pulses or a pulse-free control diet (n=8/group) for 4weeks. Pulse powders, control diet and urine samples were extracted using acetonitrile and analyzed by a high-performance liquid chromatography/quadrupole time-of-flight mass spectrometry (LC-QTOF-MS). Twenty-seven metabolites were significantly different in urine samples from lentil-fed SHR compared to SHR fed control diet, but only 7 were not present in the urine of SHR fed other pulses. Of these metabolites, only citrulline is linked to blood pressure regulation via production of the vasodilator nitric oxide (NO). Several arginine-related compounds that are NO synthase substrates or inhibitors were detected in lentils but not the control diet or other pulse powders. Consumption of lentils increases the availability of arginine and several related compounds that could potentially elevate production of NO and contribute to the blood pressure-lowering effects of lentil-rich diets.

New Potential Biomarker for Methasterone Misuse in Human Urine by Liquid Chromatography Quadrupole Time of Flight Mass Spectrometry.

In this study, methasterone urinary metabolic profiles were investigated by liquid chromatography quadrupole time of flight mass spectrometry (LC-QTOF-MS) in full scan and targeted MS/MS modes with accurate mass measurement. A healthy male volunteer was asked to take the drug and liquid–liquid extraction was employed to process urine samples. Chromatographic peaks for potential metabolites were hunted out with the theoretical [M − H]− as a target ion in a full scan experiment and actual deprotonated ions were studied in targeted MS/MS experiment. Fifteen metabolites including two new sulfates (S1 and S2), three glucuronide conjugates (G2, G6 and G7), and three free metabolites (M2, M4 and M6) were detected for methasterone. Three metabolites involving G4, G5 and M5 were obtained for the first time in human urine samples. Owing to the absence of helpful fragments to elucidate the steroid ring structure of methasterone phase II metabolites, gas chromatography mass spectrometry (GC-MS) was employed to obtain structural information of the trimethylsilylated phase I metabolite released after enzymatic hydrolysis and the potential structure was inferred using a combined MS method. Metabolite detection times were also analyzed and G2 (18-nor-17β-hydroxymethyl-2α, 17α-dimethyl-androst-13-en-3α-ol-ξ-O-glucuronide) was thought to be new potential biomarker for methasterone misuse which can be detected up to 10 days.

Liquid chromatography-quadrupole-time-of-flight mass spectrometry screening procedure for urine samples in forensic casework compared to gas chromatography-mass spectrometry.

This work represents the development, validation, and application of a liquid chromatography-quadrupole-time-of-flight mass spectrometry (LC-QTOF-MS) screening method for the detection of pharmaceutical substances and illicit drugs (acidic, basic, and neutral organic drugs) in urine samples. Time-of-flight mass spectrometry was performed using an LC-Triple TOF 5600 system with electrospray ionization operated in both positive and negative mode, respectively. The limits of detection (LODs), determined for 34 substances, were < 10 ng/mL for 91% of the compounds. The limits of quantitation (LOQs) were < 20 ng/mL for 91% of the substances. The identification of the compounds was based on exact mass (< ± 5 ppm), retention time (<2%) if available, isotopic pattern fit (<10%) and library hit (>70%). These four parameters served as identification criteria and are discussed according to their role in identifying compounds even without reference substances. In routine casework, two in-house XIC (extracted ion chromatogram) lists, consisting of 456 protonated and 26 deprotonated compounds were used and retention times for 365 compounds were available. Compared to the results found with the established gas chromatography-mass spectrometry (GC-MS) procedure, the findings with the LC-QTOF-MS screening method showed a good comparability. Results that were not detected by LC-QTOF-MS because of a missing entry in the targeted XIC list could retrospectively be confirmed by simply entering the elemental formula of the relevant substance into the software and reprocessing the sample. LC-QTOF-MS offers an attractive technique for the fast and specific identification of illicit drugs and toxic compounds in urine samples. Copyright © 2016 John Wiley & Sons, Ltd.

Identification of five pyrrolidinyl substituted cathinones and the collision‐induced dissociation of electrospray‐generated pyrrolidinyl substituted cathinones

This article reports on the analytical properties of five pyrrolidinyl substituted cathinones: α-pyrrolidinononaphenone (α-PNP, 1), 4-chloro-α-pyrrolidinopropiophenone (4-Cl-α-PPP, 2), 4-chloro-α-pyrrolidinovalerophenone (4-Cl-α-PVP, 3), 5-dihydrobenzofuranpyrovalerone (5-DBFPV, 4), and 2-(pyrrolidin-1-yl)-1-(5,6,7,8-tetrahydronaphthalen-2-yl)hexan-1-one (β-THNPH, 5). These identifications were based on liquid chromatography-quadrupole time-of-flight-mass spectrometry (LC-QTOF-MS), gas chromatography-mass spectrometry (GC-MS) and nuclear magnetic resonance spectroscopy (NMR). To our knowledge, no analytical data about α-PNP, 4-Cl-α-PPP, 4-Cl-α-PVP, and β-THNPH have appeared until now, making this the first report on these compounds. Moreover, in order to study the collision-induced dissociation (CID) characteristic fragmentation routes of pyrrolidinyl substituted cathinones, a total number of 13 pyrrolidinyl substituted cathinones were selected and discussed. The major fragmentation pathways under CID mode are produced, leading to the formation of characteristic ions. Product ions of [M-C4 H9 N]+ and Cn H2n N+ indicate the presence of pyrrolidinyl substitution. Characteristic fragments are also produced via the cleavages of the CH-N(CH2 )4 bond and the CO-CHN bond. Copyright © 2016 John Wiley & Sons, Ltd.

Oxidative degradation of triclosan by potassium permanganate: Kinetics, degradation products, reaction mechanism, and toxicity evaluation

In this study, we systematically investigated the potential applicability of potassium permanganate for removal of triclosan (TCS) in water treatment. A series of kinetic experiments were carried out to study the influence of various factors, including the pH, oxidant doses, temperature, and presence of typical anions (Cl−, SO42−, NO3−), humic acid (HA), and fulvic acid (FA) on triclosan removal. The optimal reaction conditions were: pH = 8.0, [TCS]0:[KMnO4]0 = 1:2.5, and T = 25 °C, where 20 mg/L of TCS could be completely degraded in 120 s. However, the rate of TCS (20 μg/L) oxidation by KMnO4 ([TCS]0:[KMnO4]0 = 1:2.5) was 1.64 × 10−3 mg L−1·h−1, lower than that at an initial concentration of 20 mg/L (2.24 × 103 mg L−1·h−1). A total of eleven products were detected by liquid chromatography-quadrupole-time-of-flight-mass spectrometry (LC-Q-TOF-MS) analysis, including phenol and its derivatives, benzoquinone, an organic acid, and aldehyde. Two main reaction pathways involving CO bond cleavage (−C(8)O(7)−) and benzene ring opening (in the less chlorinated benzene ring) were proposed, and were further confirmed based on frontier electron density calculations and point charges. Furthermore, the changes in the toxicity of the reaction solution during TCS oxidation by KMnO4 were evaluated by using both the luminescent bacteria Photobacterium phosphoreum and the water flea Daphnia magna. The toxicity of 20 mg/L triclosan to D. magna and P. phosphoreum after 60 min was reduced by 95.2% and 43.0%, respectively. Phenol and 1,4-benzoquinone, the two representative degradation products formed during permanganate oxidation, would yield low concentrations of DBPs (STHMFP, 20.99–278.97 μg/mg; SHAAFP, 7.86 × 10−4−45.77 μg/mg) after chlorination and chloramination. Overall, KMnO4 can be used as an effective oxidizing agent for TCS removal in water and wastewater treatment.

Identification of biotransformation products of citalopram formed in activated sludge

Citalopram (CTR) is a worldwide highly consumed antidepressant which has demonstrated incomplete removal by conventional wastewater treatment. Despite its global ubiquitous presence in different environmental compartments, little is known about its behaviour and transformation processes during wastewater treatment. The present study aims to expand the knowledge on fate and transformation of CTR during the biological treatment process. For this purpose, batch reactors were set up to assess biotic, abiotic and sorption losses of this compound. One of the main objectives of the study was the identification of the formed transformation products (TPs) by applying suspect and non-target strategies based on liquid chromatography quadrupole-time-of-flight mass spectrometry (LC-QTOF-MS). The complementary use of reversed phase liquid chromatography (RPLC) and hydrophilic interaction liquid chromatography (HILIC) for the identification of polar TPs, and the application of in-house developed quantitative structure-retention relationship (QSRR) prediction models, in addition to the comprehensive evaluation of the obtained MS/MS spectra, provided valuable information to support identification. In total, fourteen TPs were detected and thirteen of them were tentatively identified. Four compounds were confirmed (N-desmethylCTR, CTR amide, CTR carboxylic acid and 3-oxo-CTR) through the purchase of the corresponding reference standard. Probable structures based on diagnostic evidence were proposed for the additional nine TPs. Eleven TPs are reported for the first time. A transformation pathway for the biotransformation of CTR was proposed. The presence of the identified TPs was assessed in real wastewater samples through retrospective analysis, resulting in the detection of five compounds. Finally, the potential ecotoxicological risk posed by CTR and its TPs to different trophic levels of aquatic organisms was evaluated by means of risk quotients.

Identification and analytical characterization of four synthetic cathinone derivatives iso-4-BMC, β-TH-naphyrone, mexedrone, and 4-MDMC.

New psychoactive substances (NPS) have gained much popularity on the global market over the last number of years. The synthetic cathinone family is one of the most prominent groups and this paper reports on the analytical properties of four synthetic cathinone derivatives: (1) 1-(4-bromophenyl)-1-(methylamino)propan-2-one (iso-4-BMC or iso-brephedrone), (2) 2-(pyrrolidin-1-yl)-1-(5,6,7,8-tetrahydronaphthalen-2-yl)pentan-1-one (β-TH-naphyrone), (3) 3-methoxy-2-(methylamino)-1-(4-methylphenyl)propan-1-one (mexedrone), and (4) 2-(dimethylamino)-1-(4-methylphenyl)propan-1-one (4-MDMC). These identifications were based on liquid chromatography-quadrupole time-of-flight-mass spectrometry (LC-QTOF-MS), gas chromatography-mass spectrometry (GC-MS) and nuclear magnetic resonance (NMR) spectroscopy. To our knowledge, no chemical or pharmacological data about compounds 1-3 have appeared until now, making this the first report on these compounds. The Raman and GC-MS data of 4 have been reported, but this study added the LC-MS and NMR data for additional characterization. Copyright © 2016 John Wiley & Sons, Ltd.

A Liquid Chromatography‐Quadrupole‐Time of Flight Mass Spectrometry (LC‐Q‐TOF MS) Study for Analyzing 35 Corticosteroid Compounds: Elucidation of MS/MS Fragmentation Pathways

Corticosteroids have been often found to be added to a dietary supplement for the purpose of illegally improving the effect of their products. Thus, it is imperative to develop or improve a method that enables one to rapidly and reliably analyze corticosteroids in health or dietary supplements, for the safety management purpose. In the present study, results from liquid chromatography‐quadrupole time‐of‐flight mass spectrometry (LC‐Q‐TOF‐MS) experiments for the selected 35 corticosteroid compounds are presented, which can be useful for the qualitative screening of corticosteroids in health or dietary supplements. Specifically, retention times, accurate mass data of the protonated steroids, m/z values of major fragment ions are given for the 35 corticosteroids. Further, fragmentation pathways for the selected steroids are also suggested. Based on the suggested fragmentation pathways, it was shown that an unknown steroid compound can be readily identified using the knowledge of a group of unique and specific common skeletal fragments. The high selectivity and sensitivity of the LC‐Q‐TOF‐MS/MS results combined with the knowledge of the fragmentation pathways can offer a new opportunity for rapid and accurate screening of corticosteroids, thus preventing health‐related incidents involving adulterated products and clamping down on illegally circulated health products.

Nitenpyram degradation in finished drinking water.

Neonicotinoid pesticides and their metabolites have been indicated as contributing factors in the decline of honey bee colonies. A thorough understanding of neonicotinoid toxicity requires knowledge of their metabolites and environmental breakdown products. This work investigated the rapid degradation of the neonicotinoid nitenpyram in finished drinking water. Nitenpyram reaction products were characterized using liquid chromatography/quadrupole time-of-flight mass spectrometry (LC/QTOFMS). A software algorithm that compared degraded and control samples was utilized to facilitate efficient data reduction. Fragmentation pathways for six reaction products and nitenpyram were proposed using predictive software and manual product ion analysis. This study showed that nitenpyram degradation in unpreserved finished drinking water was likely the result of oxidation, hydrolysis and reaction with Cl2 . Structures for six nitenpyram reaction products were proposed that suggest the C9/C11 olefin as the key reactive site. Similarities between the identified nitenpyram reaction products and imidacloprid metabolites highlight the importance of this study, as the toxicity of neonicotinoids to pollinators has been linked to their metabolites. Based on the proposed reaction mechanisms, the identified nitenpyram reaction products in finished drinking water could also be present in the environment and water treatment facilities. As such, identifying these degradation products will aid in evaluating the environmental impact of neonicotinoid pesticides. Copyright © 2016 John Wiley & Sons, Ltd.

Identification and analytical characterization of four synthetic cannabinoids ADB-BICA, NNL-1, NNL-2, and PPA(N)-2201.

Since the first appearance as psychotropic drugs in illegal markets in 2008, the spread of synthetic cannabinoids is becoming a serious problem in many countries. This paper reports on the analytical properties and structure elucidation of four cannabimimetic derivatives in seized material: 1-benzyl-N-(1-carbamoyl-2,2-dimethylpropan-1-yl)-1H-indole-3-carboxamide (ADB-BICA, 1), N-(1-carbamoylpropan-1-yl)-1-(5-fluoropentyl)-1H-pyrrolo[2,3-b]pyridine-3-carboxamide (NNL-1, 2), (4-benzylpiperazin-1-yl)(1-(5-fluoropentyl)-1H-indol-3-yl)methanone (NNL-2, 3), and N-(1-carbamoyl-2-phenylethyl)-1-(5-fluoropentyl)-1H-indazole-3-carboxamide (PPA(N)-2201, 4). The identifications were based on liquid chromatography-quadrupole-time-of-flight-mass spectrometry (LC-QTOF-MS), gas chromatography-mass spectrometry (GC-MS), Fourier transform infrared spectroscopy (FT-IR), and nuclear magnetic resonance (NMR) spectroscopy. No chemical or pharmacological data about compounds 1-3 have appeared until now, making this the first report on these compounds. The GC-MS data of 4 has been reported, but this study added the LC-MS, FT-IR, and NMR data for additional characterization. Copyright © 2016 John Wiley & Sons, Ltd.

Identification of in vitro and in vivo human metabolites of the new psychoactive substance nitracaine by liquid chromatography coupled to quadrupole time-of-flight mass spectrometry

The purpose of this work was to investigate the in vitro metabolism of nitracaine, a new psychoactive substance, using human liver microsome incubations, to evaluate the cytochrome P450 (CYP) enzyme isoforms responsible for the phase-I metabolism and to compare the information from the in vitro experiments with data resulting from an authentic user's urine sample. Accurate mass spectra of metabolites were obtained using liquid chromatography-quadrupole time-of-flight mass spectrometry (LC-QTOF-MS) and were used in the structural identification of metabolites. Two major and three minor phase-I metabolites were identified from the in vitro experiments. The observed phase-I metabolites were formed through N-deethylation, N,N-deethylation, N-hydroxylation, and de-esterification, with CYP2B6 and CYP2C19 being the main enzymes catalyzing their formation. One glucuronidated product was identified in the phase-II metabolism experiments. All of these metabolites are reported for the first time in this study except the N-deethylation product. All the in vitro metabolites except the minor N,N-deethylation product were also present in the human urine sample, thus demonstrating the reliability of the in vitro experiments in the prediction of the in vivo metabolism of nitracaine. In addition to the metabolites, three transformation products (p-nitrobenzoic acid, p-aminobenzoic acid, and 3-(diethylamino)-2,2-dimethylpropan-1-ol) were identified, as well as several glucuronides and glutamine derived of them.

Isolation of the Binding Protein of Periplocoside E from BBMVs in Midgut of the Oriental Amyworm Mythimna separata Walker (Lepidoptera: Noctuidae) through Affinity Chromatography.

Periplocosides, which are insecticidal compounds isolated from the root bark of Periploca sepium Bunge, can affect the digestive system of insects. However, the mechanism though which periplocosides induces a series of symptoms remains unknown. In this study, affinity chromatography was conducted by coupling periplocoside E-semi-succinic acid ester with epoxy amino hexyl (EAH) sepharose 4B. Sodium dodecyl sulfonate-polyacrylamide gelelectrophoresis (SDS-PAGE) was performed to analyze the fraction eluted by periplocoside E. Eight binding proteins (luciferin 4-monooxygenase, aminopeptidase N, aminopeptidase N3, nicotinamide adenine dinucleotide health (NADH) dehydrogenase subunit 5, phosphatidylinositol 3-phosphate 3-phosphatase myotubularin, actin, uncharacterized family 31 glucosidase KIAA1161, and 2OG-Fe(2) oxygenase superfamily protein) were obtained and identified through liquid chromatography/quadrupole-time of flight-mass spectrometry (LC/Q-TOF-MS) analysis of the midgut epithelium cells of Mythimna separata larvae. Aminopeptidase N and N3 are potential putative targets of periplocosides. This study establishes the foundation for further research on the mechanism of action and target localization of periplocosides in agricultural pests.

A multi-residue method for 17 anticoccidial drugs and ractopamine in animal tissues by liquid chromatography-tandem mass spectrometry and time-of-flight mass spectrometry.

A new and sensitive multi-residue liquid chromatography-tandem mass spectrometry (LC-MS/MS) and liquid chromatography-quadrupole time-of-flight-mass spectrometry (LC-QToF-MS) method was developed and validated for the determination and confirmation of residues of 17 anticoccidials, plus free ractopamine in poultry muscle and liver, and bovine muscle, liver, and kidney tissues. The 17 anticoccidials are lasalocid, halofuginone, narasin, monensin, semduramicin, ethopabate, robenidine, buquinolate, toltrazuril as its sulfone metabolite, maduramicin, salinomycin, diclazuril, amprolium, decoquinate, dinitolmide, clopidol, and the nicarbazin metabolite DNC (N,N1-bis(4-nitrophenyl)urea). The analytes were extracted and cleaned up within a 3-hour period by simply extracting the analytes into a solvent mixture with salts followed by centrifugation, dilution, and filtration. The validated method was used in a pilot study for the analysis of 173 samples that included quail liver, bovine kidney, liver, muscle, and horse muscle. The predominant residues found in this study were monensin, ractopamine, and lasalocid. The results of this pilot study showed that this new method is applicable to real samples, and is fit for use in a regulatory testing programme. © 2016 Her Majesty the Queen in Right of Canada. Drug Testing and Analysis. © 2016 John Wiley & Sons, Ltd.

Evaluation of nitrate effects in the photodegradability of cyprodinil. Kinetics study and transformation products elucidation.

The effects of nitrate in the kinetics and the transformation routes of the fungicide cyprodinil (CYP) were investigated using aqueous solutions, ultrapure water and river water samples, spiked with the precursor compound and containing different levels of nitrate. Samples were exposed either to 254nm radiation or to solar light, depending on the experiment. Time course of CYP and formation of transformation products (TPs) were simultaneously assessed by direct injection of different irradiation time aliquots in a liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QTOF-MS) system. Empirical formulae and structures of TPs were inferred from their accurate MS and MS/MS scan spectra, respectively. Under all investigated situations, nitrate anions enhanced the degradability of CYP with a noticeable reduction of its half-life (t 1/2). TPs arising from aqueous photodegradation of CYP were formed through three different routes: (1) hydroxylation of the benzenic ring; (2) hydroxylation of the pyrimidine cycle, followed by ring opening and further dealkylation; and (3) nitration of the benzenic ring. The latter group of TPs display higher estimated acute toxicities than CYP and remained stable for long irradiation times. Graphical Abstract Photonitration of cyprodinil.

Effects of Galium aparine extract on the cell viability, cell cycle and cell death in breast cancer cell lines

Ethnopharmacological relevanceGalium species have been traditionally used for its anti-cancer, antioxidant, anti-inflammatory, antimicrobial and cardioprotective effects in the folk medicine. Galium aparine (GA) is a typical climbing plant growing widespread in Anatolia. Aim of the studyTo investigate the potential anti-proliferative and apoptotic effect of GA methanol (MeOH) extract on MCF-7 and MDA-MB-231 human breast cancer cells and MCF-10A untransformed breast epithelial cells. Materials and methodsFirst, the extract was characterized by both liquid chromatography/quadrupole time-of-flight mass spectrometry (LC/Q-TOF/MS) and gas chromatography-mass spectrometry (GC-MS) analyses. Then, cell viability and cell cycle distribution were investigated by XTT assay and PI staining by flow cytometry, respectively. Cell death was determined by Annexin V FITC/7-AAD staining. ResultsA total of 14 major phytochemicals were identified by LC/Q-TOF/MS and 34 volatile compounds were determined by GC-MS. The extract was cytotoxic in both breast cancer cell lines in a concentration and time dependent manner and showed G1 block after 72h extract treatment. However, it was not cytotoxic to MCF-10A breast epithelial cells. Flow cytometry analyses revealed that apoptosis was induced in MDA-MB-231 cells; however, necrosis was induced in MCF-7 cells. ConclusionOur study suggests that GA MeOH extract may have potential anti-cancer effects against breast cancer cells without impairing normal breast epithelial cells. Ability to induction of non-apoptotic cell death besides apoptotic cell death by this complex plant-derived mixture may enable the killing of apoptosis resistant breast cancer cells but further studies should be conducted to investigate the bioavailability and metabolism of it in vivo.

Identification of phase I and II metabolites of the new designer drug α‐pyrrolidinohexiophenone (α‐PHP) in human urine by liquid chromatography quadrupole time‐of‐flight mass spectrometry (LC‐QTOF‐MS)

After publication of this article,1, the following errors were identified. A further fragment at m/z 186.1286 (C13H16N+, mass error: 4.83 ppm) may be the product of the loss from two H2O molecules and a neutral loss of C3H6. A subsequent loss of the radical fragment C4H7O2• led to another prominent radical cation at m/z 173.1198 (C12H15N•+, mass error: −0.58 ppm).