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1.
Forensic Sci Int ; 360: 112074, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38823217

RESUMEN

Synthetic cathinones, which are novel psychoactive substances, have caused major social problems worldwide. A substance called 2-methyl-4'-(methylthio)-2-morpholinopropiophenone (MMMP), which is employed as a commercial industrial photoinitiator for triggering polymerization, has a basic cathinone backbone; however, few reports regarding MMMP have been published. In the current study, three potential metabolites of MMMP-namely hydroxy-MMMP (HO-MMMP), HO-MMMP-sulfoxide (HO-MMMP-SO), and HO-MMMP-sulfone (HO-MMMP-SO2)-were successfully synthesized, and MMMP and these three potential metabolites were used as standards to establish an analytic method based on liquid chromatography-tandem mass spectrometry for the quantitative analysis of urine. This analytic method and related parameters-including dynamic range, limit of quantification, selectivity, precision, accuracy, carryover effect, matrix effect, interference, and dilution integrity-were optimized and validated. Forty urine samples from 1,691 individuals who abused drugs were determined to contain MMMP, HO-MMMP, HO-MMMP-SO, or HO-MMMP-SO2; the results of this study indicate that approximately 2.37 % of drug abusers in Taiwan consumed MMMP in 2023. These 40 urine samples were analyzed to investigate the metabolism of MMMP in humans. The results indicate that HO-MMMP-SO is the main metabolite in human urine. This study recommends HO-MMMP-SO with a concentration of 2 ng/mL as a target and cutoff value, respectively, for identifying individuals who have consumed MMMP.


Asunto(s)
Psicotrópicos , Espectrometría de Masas en Tándem , Humanos , Psicotrópicos/orina , Psicotrópicos/análisis , Cromatografía Liquida , Propiofenonas/orina , Detección de Abuso de Sustancias/métodos , Drogas Ilícitas/análisis , Morfolinas/orina , Morfolinas/análisis , Límite de Detección
2.
Molecules ; 29(8)2024 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-38675680

RESUMEN

This study presents a method for analyzing dimethomorph residues in lychee using QuEChERS extraction and HPLC-MS/MS. The validation parameters for this method, which include accuracy, precision, linearity, and recovery, indicate that it meets standard validation requirements. Following first-order kinetics, the dissipation dynamic of dimethomorph in lychee was determined to range from 6.4 to 9.2 days. Analysis of terminal residues revealed that residues in whole lychee were substantially greater than those in the pulp, indicating that dimethomorph residues are predominantly concentrated in the peel. When applied twice and thrice at two dosage levels with pre-harvest intervals (PHIs) of 5, 7, and 10 days, the terminal residues in whole lychee ranged from 0.092 to 1.99 mg/kg. The terminal residues of the pulp ranged from 0.01 to 0.18 mg/kg, with the residue ratio of whole lychee to pulp consistently exceeding one. The risk quotient (RQ) for dimethomorph, even at the recommended dosage, was less than one, indicating that the potential for damage was negligible. This study contributes to the establishment of maximum residue limits (MRLs) in China by providing essential information on the safe application of dimethomorph in lychee orchards.


Asunto(s)
Litchi , Espectrometría de Masas en Tándem , Cromatografía Líquida de Alta Presión/métodos , Espectrometría de Masas en Tándem/métodos , Litchi/química , Morfolinas/análisis , Residuos de Plaguicidas/análisis , Contaminación de Alimentos/análisis
3.
Drug Test Anal ; 15(2): 181-191, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36239626

RESUMEN

The synthetic cannabinoid receptor agonists (SCRAs) (quinolin-8-yl 4-methyl-3-(morpholine-4-sulfonyl)benzoate [QMMSB]) and (quinolin-8-yl 4-methyl-3-((propan-2-yl)sulfamoyl)benzoate [QMiPSB], also known as SGT-46) are based on the structure of quinolin-8-yl 4-methyl-3-(piperidine-1-sulfonyl)benzoate (QMPSB) that has been identified on seized plant material in 2011. In clinical toxicology, knowledge of the metabolic fate is important for their identification in biosamples. Therefore, the aim of this study was the identification of in vitro Phase I and II metabolites of QMMSB and QMiPSB in pooled human liver S9 fraction (pHLS9) incubations for use as screening targets. In addition, the involvement of human monooxygenases and human carboxylesterases (hCES) was examined. Analyses were performed by liquid chromatography coupled with high-resolution tandem mass spectrometry. Ester hydrolysis was found to be an important step in the Phase I metabolism of both SCRAs, with the carboxylic acid product being found only in negative ionization mode. Monohydroxy and N-dealkyl metabolites of the ester hydrolysis products were detected as well as glucuronides. CYP2C8, CYP2C9, CYP3A4, and CYP3A5 were involved in hydroxylation. Whereas enzymatic ester hydrolysis of QMiPSB was mainly catalyzed by hCES1 isoforms, nonenzymatic ester hydrolysis was also observed. The results suggest that ester hydrolysis products of QMMSB and QMiPSB and their glucuronides are suitable targets for toxicological screenings. The additional use of the negative ionization mode is recommended to increase detectability of analytes. Different cytochrome P450 (CYP) isozymes were involved in the metabolism; thus, the probability of drug-drug interactions due to CYP inhibition can be assessed as low.


Asunto(s)
Agonistas de Receptores de Cannabinoides , Microsomas Hepáticos , Humanos , Agonistas de Receptores de Cannabinoides/análisis , Microsomas Hepáticos/metabolismo , Benzoatos , Isoenzimas/metabolismo , Glucurónidos/metabolismo , Sistema Enzimático del Citocromo P-450/metabolismo , Morfolinas/análisis
4.
Molecules ; 26(19)2021 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-34641333

RESUMEN

Pesticides in livestock products must be measured to ensure food safety. We developed a single-sample preparation method followed by liquid chromatography-tandem mass spectrometry (LC-MS/MS) for simultaneous determination of fenpropimorph and fenpropimorph acid in six different livestock products. The extraction method was a modification of the quick, easy, cheap, effective, rugged, and safe (QuEChERS) method and was validated according to the CODEX guidelines. The matrix-matched calibration curves for fenpropimorph and fenpropimorph acid exhibited good linearity, with coefficients of determination (R2 values) higher than 0.998. The limit of detection (LOD) and the limit of quantitation (LOQ) were 1.25 and 5.0 µg kg-1, respectively. The average recovery values ranged from 61.5% to 97.1% for samples fortified to the LOQ, 2 × LOQ, and 10 × LOQ. The method fully complied with the CODEX guidelines and was successfully applied to real samples obtained from domestic markets.


Asunto(s)
Morfolinas/análisis , Animales , Cromatografía Liquida , Análisis de los Alimentos , Límite de Detección , Ganado , Espectrometría de Masas en Tándem
5.
PLoS One ; 16(10): e0258266, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34648540

RESUMEN

Traditionally in Korea, Protaetia brevitarsis seulensis (white-spotted flower chafer) has been used as a medicine, and recently has attracted increased attention due to its antithrombotic efficacy. Some of spent mushroom compost or fermented oak sawdust, a feedstock for P. brevitarsis, were contaminated with three fungicides, carbendazim, dimethomorph, and fenoxanil, which could be transferred to the insect. This study was aimed to optimize a simple extraction method combined with liquid chromatography tandem mass spectrometry and apply it to the real samples. After the pulverized samples (5 g) were extracted with acetonitrile (10 mL) and formic acid (100 µL), fat and lipids in the samples were slowly precipitated at -20°C for 24 hours. After eight different clean-up methods were investigated, the mixture of 150 mg MgSO4/25 mg PSA/25 mg C18 was selected due to optimal recovery of the target compounds. Recovery (77.9%‒80.8% for carbendazim, 111.2%‒116.7% for dimethomorph, and 111.9%‒112.5% for fenoxanil) was achieved with reasonable relative standard deviation (<5.5%) The analytical method developed in this study was used to analyze three compounds in the 24 insect samples donated by the insect farm owners but no target compounds were detected. These results can provide important data for establishing the pesticide safety standards for P. brevitarsis before the medical applications.


Asunto(s)
Bencimidazoles/análisis , Carbamatos/análisis , Escarabajos/química , Morfolinas/análisis , Espectrometría de Masas en Tándem , Acetonitrilos/química , Animales , Cromatografía Liquida , Reproducibilidad de los Resultados
6.
Environ Sci Pollut Res Int ; 28(32): 43956-43969, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33846922

RESUMEN

Dimethomorph is a morpholine broad-spectrum fungicide and effectively controls taro blight, cucumber downy mildew, rice blast disease, and others. Fluopimomide is a newly developed broad-spectrum fungicide to primarily control oomycetes and rhizoctonia diseases. Taro, one of the earliest cultivated crops, is a staple food in Africa, Oceania, and Asia. Recently, a commercial suspension concentrate formulation containing 15% fluopimomide and 25% dimethomorph has been registered in China, the second largest taro producer in the world. The objective of this study was to develop a high-performance liquid chromatography tandem mass spectrometry method to detect the residues of fluopimomide and dimethomorph concurrently in taro samples. The results showed that the average recoveries of fluopimomide and dimethomorph ranged from 83 to 108%, and relative standard deviations (RSD) ranged from 1 to 11%. The limit of quantitation (LOQ) was 0.01 mg kg-1 for the two compounds. The dissipation results demonstrated that both fluopimomide and dimethomorph in taro degraded rapidly in taro fields, and the residues of the two fungicides were below the LOQ within 14 days post-application. The final residue levels of fluopimomide and dimethomorph in taro were lower than 0.066 mg kg-1 28 days post-application. For dietary risk assessments, the dietary structure of different genders and age of people in China exposure risk assessment and whole diet exposure risk assessment shows that the risk quotient (RQ) values were substantially lower than 100%, suggesting that the long-term risks of fluopimomide/dimethomorph mixed formulation in taro at the recommended dosage were negligible. In summary, our combined results from the dissipation behaviors, terminal residues, and dietary risk assessments provide the critical empirical data for the establishment of the maximum residue levels (MRLs) of the two broad-spectrum fungicides in taro, a traditional food for African, Oceanic, and South Asian cultures.


Asunto(s)
Colocasia , Fungicidas Industriales , Residuos de Plaguicidas , China , Cromatografía Líquida de Alta Presión , Dieta , Femenino , Fungicidas Industriales/análisis , Semivida , Humanos , Masculino , Morfolinas/análisis , Residuos de Plaguicidas/análisis , Medición de Riesgo , Espectrometría de Masas en Tándem
7.
Nature ; 586(7827): 113-119, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32707573

RESUMEN

The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in 2019 has triggered an ongoing global pandemic of the severe pneumonia-like disease coronavirus disease 2019 (COVID-19)1. The development of a vaccine is likely to take at least 12-18 months, and the typical timeline for approval of a new antiviral therapeutic agent can exceed 10 years. Thus, repurposing of known drugs could substantially accelerate the deployment of new therapies for COVID-19. Here we profiled a library of drugs encompassing approximately 12,000 clinical-stage or Food and Drug Administration (FDA)-approved small molecules to identify candidate therapeutic drugs for COVID-19. We report the identification of 100 molecules that inhibit viral replication of SARS-CoV-2, including 21 drugs that exhibit dose-response relationships. Of these, thirteen were found to harbour effective concentrations commensurate with probable achievable therapeutic doses in patients, including the PIKfyve kinase inhibitor apilimod2-4 and the cysteine protease inhibitors MDL-28170, Z LVG CHN2, VBY-825 and ONO 5334. Notably, MDL-28170, ONO 5334 and apilimod were found to antagonize viral replication in human pneumocyte-like cells derived from induced pluripotent stem cells, and apilimod also demonstrated antiviral efficacy in a primary human lung explant model. Since most of the molecules identified in this study have already advanced into the clinic, their known pharmacological and human safety profiles will enable accelerated preclinical and clinical evaluation of these drugs for the treatment of COVID-19.


Asunto(s)
Antivirales/análisis , Antivirales/farmacología , Betacoronavirus/efectos de los fármacos , Infecciones por Coronavirus/tratamiento farmacológico , Infecciones por Coronavirus/virología , Evaluación Preclínica de Medicamentos , Reposicionamiento de Medicamentos , Neumonía Viral/tratamiento farmacológico , Neumonía Viral/virología , Adenosina Monofosfato/análogos & derivados , Adenosina Monofosfato/farmacología , Alanina/análogos & derivados , Alanina/farmacología , Células Epiteliales Alveolares/citología , Células Epiteliales Alveolares/efectos de los fármacos , Betacoronavirus/crecimiento & desarrollo , COVID-19 , Línea Celular , Inhibidores de Cisteína Proteinasa/análisis , Inhibidores de Cisteína Proteinasa/farmacología , Relación Dosis-Respuesta a Droga , Sinergismo Farmacológico , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Hidrazonas , Células Madre Pluripotentes Inducidas/citología , Modelos Biológicos , Morfolinas/análisis , Morfolinas/farmacología , Pandemias , Pirimidinas , Reproducibilidad de los Resultados , SARS-CoV-2 , Bibliotecas de Moléculas Pequeñas/análisis , Bibliotecas de Moléculas Pequeñas/farmacología , Triazinas/análisis , Triazinas/farmacología , Internalización del Virus/efectos de los fármacos , Replicación Viral/efectos de los fármacos , Tratamiento Farmacológico de COVID-19
8.
J Pharm Biomed Anal ; 179: 112950, 2020 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-31761378

RESUMEN

A simple and sensitive liquid chromatography-tandem mass spectrometry (LC-MS/MS) coupled with one-step protein precipitation extraction method was developed and validated for determination of GSK2636771, a phosphoinositide 3 kinase (PI3K) inhibitor in rat plasma. After protein precipitation with acetonitrile, the chromatographic separation was carried out on a CORTECS UPLC C18 column, with acetonitrile and 0.1 % formic acid in water as mobile phase at a flow rate of 0.30 mL·min-1. The detection was performed on a triple quadrupole tandem mass spectrometer by multiple reaction monitoring (MRM) mode via electrospray ionization (ESI) source, with target quantitative ion pairs of m/z 434.2→416.2 for GSK2636771, and 411.2→367.2 for BKM120 (internal standard). The calibration curve was linear over the range of 2.0-8000 ng·mL-1, and the LLOQ was evaluated to be 2.0 ng·mL-1. The accuracy (relative error, RE %) ranged from -3.4 % to 4.7 %, and the intra- and inter-day precision were within 15 %, and with the mean extraction recovery 82.1-89.3 %. The validated method described a quantification method of GSK2636771 in detail for the first time and applied to a pharmacokinetic study after oral administration of GSK2636771 at low, medium and high doses in rats. The mean plasma concentration versus time profiles of GSK2636771 showed a dose-dependent relationship at different doses.


Asunto(s)
Cromatografía Liquida/métodos , Imidazoles/análisis , Morfolinas/análisis , Inhibidores de las Quinasa Fosfoinosítidos-3/análisis , Espectrometría de Masas en Tándem/métodos , Administración Oral , Animales , Relación Dosis-Respuesta a Droga , Imidazoles/administración & dosificación , Imidazoles/farmacocinética , Masculino , Morfolinas/administración & dosificación , Morfolinas/farmacocinética , Inhibidores de las Quinasa Fosfoinosítidos-3/administración & dosificación , Inhibidores de las Quinasa Fosfoinosítidos-3/farmacocinética , Ratas , Ratas Wistar
9.
Artículo en Inglés | MEDLINE | ID: mdl-30650034

RESUMEN

Morpholine is a common chemical used as emulsifier in the preparation of wax coatings for some fruit to help them remain fresh and protect against insects and fungal contamination. It has been reported that morpholine has acute toxic effects on rodents. In the present study, morpholine concentrations were analysed in fruits (citrus fruits, apples, strawberries and grapes) and juices (apple juice and orange juice) in order to determine dietary exposure among the Chinese population. A total of 732 fruit and juice samples were collected during 2015-2016, which covered major foods in China. Fruit and juice consumption data were taken from China National Nutrient and Health Survey (2002) and include data from 16,407 fruit or juice consumers. It was found that mean dietary exposure to morpholine residues from fruits and/or juices for general Chinese consumers and children 2-6 years old were 0.42 and 1.24 µg/kg bw/day, respectively. The 97.5% intake in general Chinese consumers and children 2-6 years old were 2.25 and 6.90 µg/kg bw/day, respectively. The primary food sources of the morpholine dietary intake of general Chinese consumers were citrus fruits (57.4%) and apples (40.8%). These findings suggested that dietary exposure to morpholine in the Chinese population was lower than the acceptable daily intake of morpholine, and there are no health concerns.


Asunto(s)
Dieta/estadística & datos numéricos , Exposición Dietética , Contaminación de Alimentos/análisis , Jugos de Frutas y Vegetales/análisis , Frutas/química , Morfolinas/análisis , China
10.
Regul Toxicol Pharmacol ; 100: 72-79, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30359702

RESUMEN

The residue behavior and dietary intake risk of two fungicides (dimethomorph and pyraclostrobin) in grape (Vitis vinifera L.) were investigated from field trials. A modified quick, easy, cheap, effective, rugged, and safe method for simultaneously determining dimethomorph and pyraclostrobin residues in grape and soil was established using high performance liquid chromatography-tandem mass spectrometry. The average recoveries of dimethomorph and pyraclostrobin in the grape and soil matrices varied from 76.88% to 97.05%, with relative standard deviations of 1.73%-10.38%. The degradation half-lives of dimethomorph and pyraclostrobin were 7.3-12.0 days and 3.6-7.0 days in grape and soil, respectively. The terminal residues of dimethomorph and pyraclostrobin in the two matrices were 0.05-0.87 mg/kg. For dietary exposure risk assessments, all of the hazard quotient and hazard quotient index values were below 100%, which indicated that the suspending agents of dimethomorph and pyraclostrobin were sprayed on grape at the recommended dosages with no significant potential risks for Chinese consumers. This study provides a reference for analytically evaluating residual degradation behavior and dietary intake risk of two fungicides under field conditions.


Asunto(s)
Exposición a Riesgos Ambientales/análisis , Frutas/química , Fungicidas Industriales/análisis , Morfolinas/análisis , Residuos de Plaguicidas/análisis , Contaminantes del Suelo/análisis , Estrobilurinas/análisis , Vitis , Adolescente , Adulto , Anciano , Niño , Preescolar , Dieta , Femenino , Contaminación de Alimentos/análisis , Humanos , Cinética , Masculino , Persona de Mediana Edad , Medición de Riesgo , Adulto Joven
11.
Artículo en Inglés | MEDLINE | ID: mdl-30211663

RESUMEN

A general solid-phase extraction (SPE) method using ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) for the determination of moroxydine residues in pig and chicken samples has been developed. After extraction and purification of real samples, moroxydine residues were detected using a hydrophobic interaction liquid chromatography column with an optimised mobile phase composition. The extraction reagents, the kind of SPE columns and the type of eluents were optimised to achieve the maximum extraction efficiency. The matrix effects from the animal tissue influenced the quality of the quantitative data obtained. Under the optimised conditions, the moroxydine residues in pig and chicken samples spiked at three levels (1.0 µg/kg, 5.0 µg/kg and 10.0 µg/kg) were determined with good recoveries (61.5%-105.4%) and adequate relative standard deviations (3.2%-13.0%). In pig and chicken samples, the limit of detection (LOD) was 0.3 µg/kg, and the limit of quantification (LOQ) was 1.0 µg/kg. A sufficiently linear relationship in the range of 1.0 µg/kg-20.0 µg/kg was achieved with a good correlation coefficient (R2 ≥ 0.99).


Asunto(s)
Antivirales/análisis , Residuos de Medicamentos/análisis , Análisis de los Alimentos , Morfolinas/análisis , Animales , Biguanidas , Pollos , Cromatografía Líquida de Alta Presión , Extracción en Fase Sólida , Porcinos , Espectrometría de Masas en Tándem
12.
Environ Sci Pollut Res Int ; 25(32): 32783-32790, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30251039

RESUMEN

Fluazinam and dimethomorph 35% suspension concentrate (SC) is a new combined fungicide formulation introduced in China to improve fungicidal efficacy and decrease the risk of resistance in potatoes. Fluazinam and dimethomorph dissipation and residues in potatoes, potato plants, and soil under field conditions were determined by ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS). Fluazinam and dimethomorph 35% SC was applied at two doses to potatoes and soil in Ningxia Autonomous Region and Anhui Province, China. Fluazinam and dimethomorph dissipation fitted first-order kinetics, and the fluazinam half-lives in potato plants and soil were 3.3-5.4 and 9.4-9.5 days, respectively. The dimethomorph half-lives in potato plants and soil were 2.1-2.6 and 5.9-8.6 days, respectively. Fluazinam and dimethomorph 35% SC was sprayed onto potato plants three or four times at application rates of 420 and 630 g a.i. ha-1 with 7 days between applications. Potato and soil samples were collected at 3, 7, and 14 days after the last application. Potatoes and soil had fluazinam concentrations of < 0.01 and < 0.05-0.183 mg kg-1, respectively, and dimethomorph concentrations of < 0.01 and 0.129-0.677 mg kg-1, respectively. The final fluazinam and dimethomorph concentrations in potatoes were below the EU maximum residue limits (0.02 and 0.05 mg kg-1, respectively) 3 days after application. Fluazinam and dimethomorph can therefore be applied to potatoes at the recommended doses.


Asunto(s)
Aminopiridinas/análisis , Fungicidas Industriales/análisis , Morfolinas/análisis , Residuos de Plaguicidas/análisis , Solanum tuberosum/química , China , Cromatografía Liquida , Semivida , Cinética , Suelo , Contaminantes del Suelo , Espectrometría de Masas en Tándem
13.
J Food Drug Anal ; 26(3): 1160-1170, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29976408

RESUMEN

In the present study, we compare the performance of two reversed-phase liquid chromatographic approaches using different eluents either conventional hydro-organic eluent or micellar one for simultaneous estimation of hydrocortisone acetate and pramoxine hydrochloride in presence of their degradants and process-related impurities; hydrocortisone and 4-butoxyphenol, respectively. For conventional reversed-phase liquid chromatography (RPLC), separation of the studied compounds was completed on an Inertsil ODS 3-C18 column (150 mm × 4.6 mm, 5 µm particle size) with a mobile phase consists of 50 mM phosphate buffer (pH 5.0): acetonitrile (50: 50, v/v). For micellar liquid chromatography (MLC), an Eclipse XDB-C8 column (150 mm × 4.6 mm, 5 µm particle size) was chosen for the separation with a green mobile phase consists of 0.15 M sodium dodecyl sulfate, 0.3% triethylamine and 10% n-butanol in 20 mM orthophosphoric acid (pH 5.0). Both methods were extended to analyze hydrocortisone acetate and pramoxine hydrochloride in their co-formulated cream. RPLC was superior to MLC with regard to sensitivity for the estimation of impurities. While, MLC represents an eco-friendly, less hazardous and biodegradable approach. Furthermore, the direct injection of the cream to the system without the need to laborious samples pretreatment, excessive amount of analysis time and/or use of large amount of toxic organic solvents is one of the outstanding advantages of MLC.


Asunto(s)
Cromatografía de Fase Inversa/métodos , Hidrocortisona/análogos & derivados , Morfolinas/análisis , Contaminación de Medicamentos , Hidrocortisona/análisis
14.
Biomed Chromatogr ; 32(7): e4231, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29500932

RESUMEN

MS Binding Assays represent a label-free alternative to radioligand binding assays. In this study, we present an LC-ESI-MS/MS method for the quantification of (R,R)-4-(2-benzhydryloxyethyl)-1-(4-fluorobenzyl)piperidin-3-ol [(R,R)-D-84, (R,R)-1], (S,S)-reboxetine [(S,S)-2], and (S)-citalopram [(S)-3] employed as highly selective nonlabeled reporter ligands in MS Binding Assays addressing the dopamine [DAT, (R,R)-D-84], norepinephrine [NET, (S,S)-reboxetine] and serotonin transporter [SERT, (S)-citalopram], respectively. The developed LC-ESI-MS/MS method uses a pentafluorphenyl stationary phase in combination with a mobile phase composed of acetonitrile and ammonium formate buffer for chromatography and a triple quadrupole mass spectrometer in the multiple reaction monitoring mode for mass spectrometric detection. Quantification is based on deuterated derivatives of all three analytes serving as internal standards. The established LC-ESI-MS/MS method enables fast, robust, selective and highly sensitive quantification of all three reporter ligands in a single chromatographic run. The method was validated according to the Center for Drug Evaluation and Research (CDER) guideline for bioanalytical method validation regarding selectivity, accuracy, precision, calibration curve and sensitivity. Finally, filtration-based MS Binding Assays were performed for all three monoamine transporters based on this LC-ESI-MS/MS quantification method as read out. The affinities determined in saturation experiments for (R,R)-D-84 toward hDAT, for (S,S)-reboxetine toward hNET, and for (S)-citalopram toward hSERT, respectively, were in good accordance with results from literature, clearly demonstrating that the established MS Binding Assays have the potential to be an efficient alternative to radioligand binding assays widely used for this purpose so far.


Asunto(s)
Compuestos de Bencidrilo/análisis , Cromatografía Liquida/métodos , Citalopram/análisis , Morfolinas/análisis , Piperidinas/análisis , Simportadores/metabolismo , Animales , Compuestos de Bencidrilo/metabolismo , Citalopram/metabolismo , Humanos , Morfolinas/metabolismo , Piperidinas/metabolismo , Unión Proteica , Reboxetina , Reproducibilidad de los Resultados , Espectrometría de Masa por Ionización de Electrospray/métodos , Espectrometría de Masas en Tándem/métodos
15.
J Pharm Biomed Anal ; 150: 152-161, 2018 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-29245084

RESUMEN

In the research presented we report the development of a simple and robust liquid chromatographic method for the quantification of two genotoxic alkyl sulphonate impurities (namely methyl p-toluenesulfonate and isopropyl p-toluenesulfonate) in Aprepitant API substances using the Analytical Quality by Design (AQbD) approach. Following the steps of AQbD protocol, the selected critical method attributes (CMAs) were the separation criterions between the critical peak pairs, the analysis time and the peak efficiencies of the analytes. The critical method parameters (CMPs) included the flow rate, the gradient slope and the acetonitrile content at the first step of the gradient elution program. Multivariate experimental designs namely Plackett-Burman and Box-Behnken designs were conducted sequentially for factor screening and optimization of the method parameters. The optimal separation conditions were estimated using the desirability function. The method was fully validated in the range of 10-200% of the target concentration limit of the analytes using the "total error" approach. Accuracy profiles - a graphical decision making tool - were constructed using the results of the validation procedures. The ß-expectation tolerance intervals did not exceed the acceptance criteria of±10%, meaning that 95% of future results will be included in the defined bias limits. The relative bias ranged between - 1.3-3.8% for both analytes, while the RSD values for repeatability and intermediate precision were less than 1.9% in all cases. The achieved limit of detection (LOD) and the limit of quantification (LOQ) were adequate for the specific purpose and found to be 0.02% (corresponding to 48µgg-1 in sample) for both methyl and isopropyl p-toluenesulfonate. As proof-of-concept, the validated method was successfully applied in the analysis of several Aprepitant batches indicating that this methodology could be used for routine quality control analyses.


Asunto(s)
Bencenosulfonatos/análisis , Cromatografía Líquida de Alta Presión , Contaminación de Medicamentos , Morfolinas/análisis , Tecnología Farmacéutica/métodos , Aprepitant , Calibración , Cromatografía Líquida de Alta Presión/normas , Límite de Detección , Análisis Multivariante , Control de Calidad , Estándares de Referencia , Reproducibilidad de los Resultados , Tecnología Farmacéutica/normas
16.
Food Chem ; 244: 71-74, 2018 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-29120807

RESUMEN

An efficient method has been developed for determining tridemorph in banana using high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). The dissipation and terminal residue of tridemorph in banana fields were carried out at good agricultural practice (GAP) conditions. The average recoveries ranged from 84.4% to 90.0% with relative standard deviations (RSDs) of 3.0%-7.0% at three different spiking levels. The results indicated that the tridemorph dissipated quickly in banana with half-lives of 7.0-7.7days. The results of residual distribution ranged from 0.01 to 0.26mg/kg, 0.01-0.62mg/kg and <0.01mg/kg in whole banana, peel and pulp, respectively. The relationship between application factor and residue was discussed. The results of risk assessment showed that the risk quotient (RQ) value was all below RQ=1. Given that China has not set an maximum residue limit (MRL) value for tridemorph in banana, this study could provide guidance for the reasonable use of tridemorph.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Análisis de los Alimentos/métodos , Morfolinas/análisis , Musa/química , Espectrometría de Masas en Tándem/métodos , China , Contaminación de Alimentos/análisis , Semivida , Morfolinas/metabolismo , Residuos de Plaguicidas/análisis , Residuos de Plaguicidas/metabolismo , Medición de Riesgo
17.
Drug Test Anal ; 10(2): 272-283, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28513099

RESUMEN

New psychoactive substances (NPS) are commonly referred to as 'research chemicals', 'designer drugs' or 'legal highs'. One NPS class is represented by dissociative anesthetics, which include analogues of the arylcyclohexylamine phencyclidine (PCP), ketamine and diphenidine. A recent addition to the NPS market was 4-[1-(3-methoxyphenyl)cyclohexyl]morpholine (3-MeO-PCMo), a morpholine analogue of 3-MeO-PCP. Although suspected to have dissociative effects in users, information about its pharmacological profile is not available. From clinical and forensic perspectives, detailed analytical data are needed for identification, especially when facing the presence of positional isomers, as these are frequently unavailable commercially. This study presents the analytical and pharmacological characterization of 3-MeO-PCMo along with five additional analogues, namely the 2- and 4-MeO-PCMo isomers, 3,4-methylenedioxy-PCMo (3,4-MD-PCMo), 3-Me-PCMo and PCMo. All six arylcyclohexylmorpholines were synthesized and characterized using chromatographic, mass spectrometric and spectroscopic techniques. The three positional isomers could be differentiated and the identity of 3-MeO-PCMo obtained from an internet vendor was verified. All six compounds were also evaluated for affinity at 46 central nervous system receptors including the N-methyl-d-aspartate receptor (NMDAR), an important target for dissociative anesthetics such as PCP and ketamine. In vitro binding studies using (+)-[3-3 H]-MK-801 in rat forebrain preparations revealed moderate affinity for NMDAR in the rank order of 3-Me >3-MeO > PCMo >3,4-MD > 2-MeO > 4-MeO-PCMo. 3-MeO-PCMo was found to have moderate affinity for NMDAR comparable to that of ketamine, and had an approximate 12-fold lower affinity than PCP. These results support the anecdotal reports of dissociative effects from 3-MeO-PCMo in humans.


Asunto(s)
Anestésicos Disociativos/química , Ketamina/farmacología , Morfolinas/análisis , Morfolinas/síntesis química , Morfolinas/farmacología , Fenciclidina/análogos & derivados , Piperidinas/farmacología , Receptores de N-Metil-D-Aspartato/química , Receptores de N-Metil-D-Aspartato/metabolismo , Anestésicos Disociativos/metabolismo , Animales , Humanos , Ketamina/química , Fenciclidina/análisis , Fenciclidina/síntesis química , Fenciclidina/farmacología , Piperidinas/química , Ratas
18.
Biomed Chromatogr ; 32(2)2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28731579

RESUMEN

Residue analysis of dimethomorph in Swiss chard cultivated at two different locations under greenhouse conditions was conducted using high-performance liquid chromatography-ultraviolet detection and confirmed by tandem mass spectrometry. The randomly collected samples (over 14 days) were extracted with acetonitrile and purified using a Florisil solid-phase extraction cartridge. Linearity over a concentration range of 0.05-50.0 mg/L had an excellent coefficient of determination of 0.9996. Recovery rate ranged from 82.98 to 95.43% with relative standard deviations ≤5.12% and limits of detection and quantification of 0.003 and 0.01 mg/kg, respectively. The initial deposits [day 0 (2 h post-application)] were considerably lower (7.57 and 8.55 mg/kg for sites 1 and 2, respectively) than the maximum residue limit (30 mg/kg) set by the Korean Ministry of Food and Drug Safety. The dissipation half-life was approximately the same, being 5.0 and 5.1 days for sites 1 and 2, respectively. Risk assessment estimated as acceptable daily intake revealed a value of 0.084 or 0.094% (day 0) and 0.014% (10 days post-application), for sites 1 and 2, respectively. The values indicated that dimethomorph can be safely used on Swiss chard, with no hazardous effects expected for Korean consumers.


Asunto(s)
Beta vulgaris/química , Morfolinas/análisis , Residuos de Plaguicidas/análisis , Cromatografía Líquida de Alta Presión/métodos , Inocuidad de los Alimentos , Límite de Detección , Modelos Lineales , Morfolinas/química , Residuos de Plaguicidas/química , Reproducibilidad de los Resultados , República de Corea , Medición de Riesgo , Espectrometría de Masas en Tándem/métodos
19.
J AOAC Int ; 101(2): 414-426, 2018 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-28766478

RESUMEN

The presence of coloring matters in syrups usually interferes with the spectrophotometric determination of active pharmaceutical ingredients. A novel approach was introduced to eliminate the interference of sunset yellow (coloring matter) in Cyrinol syrup. Smart, simple, accurate, and selective spectrophotometric methods were developed and validated for the simultaneous determination of a ternary mixture of carbinoxamine maleate, pholcodine, and ephedrine hydrochloride in syrup. Four of the applied methods used ratio spectra: successive derivative subtraction coupled with constant multiplication, successive derivative of ratio spectra, ratio subtraction coupled with ratio difference, and ratio spectra continuous wavelet transforms zero-crossing. In addition, a method that was based on the presence of an isosbestic point, the amplitude summation method, was also established. A major advantage of the proposed methods is the simultaneous determination of the mentioned drugs without prior separation steps. These methods were successfully applied for the determination of laboratory-prepared mixtures and a commercial pharmaceutical preparation without interference from additives, thus proving the selectivity of the methods. No significant difference regarding both accuracy and precision was observed upon statistical comparison of the results obtained by the proposed methods with each other and with those of official or reported ones.


Asunto(s)
Compuestos Azo/química , Codeína/análogos & derivados , Colorantes/química , Efedrina/análisis , Morfolinas/análisis , Piridinas/análisis , Espectrofotometría/métodos , Antitusígenos/análisis , Codeína/análisis , Límite de Detección
20.
Mycoses ; 60(12): 800-807, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28925059

RESUMEN

Patient adherence is a key consideration in the choice of a topical regimen for the treatment of onychomycosis. The objective of this study was to investigate patient-reported outcomes (treatment utilisation, adherence and satisfaction) in onychomycosis treated with once-weekly amorolfine 5% nail lacquer versus once-daily ciclopirox 8% nail lacquer (Study A) or once-daily urea 40% ointment/bifonazole 1% cream combination regimen (Study B). Study A: Subjects received amorolfine and ciclopirox on opposite feet for 12 weeks. Study B: Subjects received amorolfine and urea/bifonazole on opposite feet for 6-7 weeks. Assessments included subject adherence as per label, treatment preference and questionnaire. Study A: More subjects adhered to amorolfine (85%) than to ciclopirox (60%) (P = .025). Overall, subjects were satisfied (95% vs 100%, respectively) and the treatments were balanced in terms of preference (50% vs 45%) at week 12. Study B: More subjects adhered to amorolfine dosage (81.8%) than to the dosage of the urea/bifonazole combination regimen (59.1%) (P = .096). At the end of study, 85.7% of subjects preferred amorolfine versus 14.3% for urea/bifonazole. Fewer subjects experienced local side effects with amorolfine (4.5%) compared to urea (27.3%) and bifonazole (15%). Amorolfine 5% nail lacquer offers a simple and convenient treatment option, which may result in improved patient adherence and consequently lead to improved efficacy and patient satisfaction.


Asunto(s)
Antifúngicos/administración & dosificación , Dermatosis del Pie/tratamiento farmacológico , Morfolinas/administración & dosificación , Onicomicosis/tratamiento farmacológico , Administración Tópica , Adulto , Anciano , Ciclopirox , Esquema de Medicación , Femenino , Dermatosis del Pie/psicología , Humanos , Imidazoles/administración & dosificación , Laca/análisis , Masculino , Cumplimiento de la Medicación , Persona de Mediana Edad , Morfolinas/análisis , Onicomicosis/psicología , Medición de Resultados Informados por el Paciente , Piridonas/administración & dosificación
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