RESUMEN
In this work, a method based on ultra-high-performance liquid chromatography with a photodiode array detector (UPLC-PDA) was developed to comprehensively analyze phenolic compounds in peels of lime (Citrus × latifolia), lemon (Citrus limon), and rangpur lime (Citrus × limonia). The reverse-phase separation was achieved with a C18 fused-core column packed with the smallest particles commercially available (1.3 um). The method was successfully coupled with high-resolution mass spectrometry (HRMS), allowing the detection of 24 phenolic compounds and five limonoids in several other citrus peels species: key lime, orange and sweet orange, tangerine, and tangerine ponkan, proving the suitability for comprehensive analysis in citrus peel matrices. Additionally, the developed method was validated according to the Food and drug administration (FDA) and National Institute of Metrology Quality and Technology (INMETRO) criteria, demonstrating specificity, linearity, accuracy, and precision according to these guidelines. System suitability parameters such as resolution, tailoring, plate count were also verified.
RESUMEN
Elicitation of cell suspensions culture is a strategy that could increase the production of secondary metabolites under controlled conditions. This research evaluated the effect of methyl jasmonate-MeJA and salicylic acid-SA as elicitors on the production of metabolites in cell suspensions of P. cumanense. The type of elicitor (MeJA or SA), the concentration of elicitor (10⯵M and 100⯵M), and time of exposition (3, 12, 24â¯h) on cell suspension were evaluated. Metabolic profiles of intracellular and extracellular extracts were analyzed by UHPLC-DAD and GC-MS. Differential production of metabolites was dependent on the type of elicitor, its concentration, and the time of exposition. Treatments with 100 µM SA were conducted to high production of 5-hydroxymethylfurfural (6.3 %), phenol (6.5 %), and (Z)-9-octadecenamide (8.8 %). This is the first report of elicitation on cell suspensions in the Piper genus and contributes to understanding the effect of MeJA and SA on metabolite production in plant cell culture.
RESUMEN
A simple and reliable method was developed and validated to determine the endocannabinoids anandamide (AEA) and 2-arachidonoylglycerol (2-AG) in rat brain samples by micro salting-out assisted liquid-liquid extraction combined with ultra-high performance liquid chromatography tandem mass spectrometry (SALLLE/UHPLC-MS/MS). The SALLE parameters (brain homogenate volume, salting-out agent, salt concentration, salt solution volume, organic solvent, organic solvent volume, and centrifugation temperature) were optimized to improve sensitivity and selectivity of the method. The SALLE/UHPLC-MS/MS method presented linear ranges from 2.00 to 20.00 ng mL-1 for AEA and from 0.300 to 10.00 µg mL-1 for 2-AG, no significant matrix effect, and inter- and intra-assay precision and accuracy with CV and RSE values lower than 15%, respectively. This innovative method was successfully applied to determine AEA and 2-AG in brain hemispheres from a 6-OHDA animal model of Parkinson's disease (PD).
Asunto(s)
Ácidos Araquidónicos/análisis , Química Encefálica/fisiología , Endocannabinoides/análisis , Glicéridos/análisis , Extracción Líquido-Líquido/métodos , Alcamidas Poliinsaturadas/análisis , Animales , Ácidos Araquidónicos/aislamiento & purificación , Cromatografía Líquida de Alta Presión/métodos , Modelos Animales de Enfermedad , Endocannabinoides/aislamiento & purificación , Glicéridos/aislamiento & purificación , Límite de Detección , Modelos Lineales , Masculino , Enfermedad de Parkinson/metabolismo , Alcamidas Poliinsaturadas/aislamiento & purificación , Ratas , Ratas Wistar , Reproducibilidad de los Resultados , Espectrometría de Masas en Tándem/métodosRESUMEN
Cleaning validation is the documented evidence that shows the effectiveness of cleaning procedures for the removal of product residues and other contaminants. The cleaning procedures must be validated and methods to determine trace amounts of drugs have to be considered with special attention. An ultra-high-performance liquid chromatography-ultraviolet (UHPLC-UV) method for the determination of mometasone furoate residues on stainless-steel surfaces was developed and validated in order to control a cleaning procedure. The chromatography separation was achieved on a Waters Acquity UPLC HSS T3 column (50 × 2.1 mm, 1.8 µm) at 40°C using acetonitrile and water (1:1, v/v) as the mobile phase at a flow rate of 0.5 mL/min. The injection volume was 2 µL, and the detection was performed at 254 nm. The swab and rinse procedures were optimized in order to obtain a recovery higher than 90% of mometasone furoate from stainless-steel surfaces, using ethanol as the extraction solvent. The method was validated in the range of 0.2-2.6 µg/mL and showed appropriate selectivity, limit of detection and quantification, linearity, precision, accuracy, and robustness. This method was found to be simple, fast, and sensitive for determination of mometasone furoate residues and, therefore, can be used for cleaning validation analysis.
Asunto(s)
Contaminación de Equipos/prevención & control , Furoato de Mometasona/análisis , Acero Inoxidable/análisis , Tecnología Farmacéutica/métodos , Tecnología Farmacéutica/normas , Rayos Ultravioleta , Cromatografía Líquida de Alta Presión/métodos , Cromatografía Líquida de Alta Presión/normas , Reproducibilidad de los ResultadosRESUMEN
This study was carried out in order to compare the relative bioavailability of two different formulations containing 400 mg of acetaminophen + 4 mg of phenylephrine hydrochloride + 4 mg of chlorpheniramine maleate, Test formulation (Cimegripe®) and Reference formulation (Resfenol®) in 84 healthy volunteers of both sexes under fasting conditions. The study was conducted in a single dose, randomized, open-label, crossover 3-way and partially replicated. The tolerability was evaluated by the monitoring of adverse events and vital signs, results of clinical and laboratory tests. Plasma concentrations were quantified by validated bioanalytical methods using the ultra-performance liquid chromatography coupled to tandem mass spectrometry. The Cmax, Tmax, AUC0-t, AUC0-inf, T1/2 and Kel pharmacokinetic parameters were calculated from these obtained concentrations. The 90% confidence intervals were constructed for the ratio reference/test from the geometric average of the Cmax and AUC parameters which were comprised between 80% and 125%. Only the Cmax parameter of the phenylephrine was applied the scaled average bioequivalence due to the intraindividual coefficient of variation > 30% obtained, thus extending the acceptance limits of the interval. It can be concluded that the two formulations were bioequivalent in terms of rate and absorption extent and thus interchangeable
Asunto(s)
Humanos , Masculino , Femenino , Fenilefrina/análisis , Cápsulas/clasificación , Disponibilidad Biológica , Clorfeniramina/análisis , Acetaminofén/análisis , Espectrometría de Masas/métodos , Dosis Única , Ayuno/efectos adversos , Estudios Cruzados , Absorción/efectos de los fármacos , Espectrometría de Masas en Tándem/métodos , Voluntarios Sanos/clasificaciónRESUMEN
It is important to study the stability of plant extracts used as active ingredients in phytotherapic medicine, as degradation of the active principles directly affects the efficacy and safety of these products. Therefore, a stability study of the hydroalcoholic extract of the species: Mikania glomerata and Mikania laevigata was conducted in order to determine the speed of degradation and shelf life of these extracts, which are incorporated in cough syrup in Brazil. Leaves of both species were dried in an oven or by lyophilization (freeze-dried). Hydroalcoholic extracts underwent both accelerated stability study of six months and long-term stability study for 12 months. Samples were stored at different temperatures and every three months were analysed by ultra-high performance liquid chromatography-mass spectrometry (UHPLC-MS) to monitor their chemical profile, quantifying coumarin and chlorogenic acid. For all conditions of the study, a reduction of the content of the chemical marker of this species, coumarin, greater than 5% was observed, so a shelf life of two years cannot be assigned to the hydroalcoholic extracts of these species as observed in commercial extracts.
Asunto(s)
Extractos Vegetales/análisis , Eficacia , Asteraceae/clasificación , Mikania/clasificación , Espectrometría de Masas/métodos , Ácido Clorogénico/efectos adversos , Cromatografía Líquida de Alta Presión/métodos , Tos , Cumarinas/clasificaciónRESUMEN
This work describes the development and validation of an ultra-high performance liquid chromatography tandem mass spectrometry method that uses disposable pipette extraction (DPX-UHPLC-MS/MS) to determine the endocannabinoid anandamide (AEA) in cerebrospinal fluid samples (CSF). The DPX parameters sorption equilibrium time, sample volume, number of draw-eject cycles, washing solvent volume, and elution solvent volume were optimized by design of experiments (DOE) techniques. The simple DPX protocol proposed herein required a reduced amount of CSF sample and organic solvent. The DPX-UHPLC-MS/MS method presented linear range from 0.10â¯ngâ¯mL-1 (LLOQ) to 3.0â¯ngâ¯mL-1, inter- and intra-assay accuracy with EPR values varying from -8.2% to 9.6%, inter- and intra-assay precision with CV values ranging from 1.3% to 14.8% (except for the LLOQ), and no significant matrix effect. The innovative DPX-UHPLC-MS/MS method was successfully applied to determine AEA in CSF samples from Parkinson's disease (PD) patients and should therefore be used in clinical studies.
Asunto(s)
Ácidos Araquidónicos/líquido cefalorraquídeo , Cromatografía Líquida de Alta Presión/métodos , Endocannabinoides/líquido cefalorraquídeo , Alcamidas Poliinsaturadas/líquido cefalorraquídeo , Espectrometría de Masas en Tándem/métodos , Ácidos Araquidónicos/aislamiento & purificación , Endocannabinoides/aislamiento & purificación , Humanos , Modelos Lineales , Alcamidas Poliinsaturadas/aislamiento & purificación , Reproducibilidad de los Resultados , Sensibilidad y EspecificidadRESUMEN
The use of fluoroquinolones for the treatment of infections in humans and animals has increased in Argentina, and they can be found in large amounts in water bodies. The present study investigated the occurrence and associated ecological risk of 5 fluoroquinolones in rivers and farm wastewaters of San Luis, Santa Fe, Córdoba, Entre Ríos, and Buenos Aires provinces of Argentina by high-performance liquid chromatography coupled to fast-scanning fluorescence detection and ultra-high-performance liquid chromatography coupled to triple quadrupole mass spectrometry detection. The maximum concentrations of ciprofloxacin, enrofloxacin, ofloxacin, enoxacin, and difloxacin found in wastewater were 1.14, 11.9, 1.78, 22.1, and 14.2 µg L-1 , respectively. In the case of river samples, only enrofloxacin was found, at a concentration of 0.97 µg L-1 . The individual risk of aquatic organisms associated with water pollution due to fluoroquinolones was higher in bacteria, cyanobacteria, algae, plants, and anurans than in crustaceae and fish, with, in some cases, risk quotients >1. The proportion of samples classified as high risk was 87.5% for ofloxacin, 63.5% for enrofloxacin, 57.1% for ciprofloxacin, and 25% for enoxacin. Our results suggest that the prevalence of fluoroquinolones in water could be potentially risky for the aquatic ecosystem, and harmful to biodiversity. Environ Toxicol Chem 2019;38:2305-2313. © 2019 SETAC.
Asunto(s)
Ecosistema , Fluoroquinolonas/análisis , Medición de Riesgo , Ríos/química , Aguas Residuales/química , Animales , Argentina , Cromatografía Líquida de Alta Presión , Exposición a Riesgos Ambientales/análisis , Geografía , Humanos , Contaminantes Químicos del Agua/análisisRESUMEN
In the present manuscript an analytical methodology for the simultaneous determination of ten mycotoxins and six pesticides in rice was developed. This methodology comprises the application of the dilute and shoot protocol followed by quantification via UHPLC-MS/MS. The methodology was validated and all figures of merit shown to be within the limits established by regulation. Hence, the recoveries for mycotoxins and pesticides were within the specified ranges. Precision was assessed by repeatability and intra-laboratory reproducibility with standard deviations smaller than or equal to 20%. The limits of detection, quantification and decision as well as the detection capacity were determined by the analytical curves whereas the measurement uncertainty was established by applying the bottom-up approach. Finally, the current methodology was applied to samples of rice (nâ¯=â¯42) commercialized in Brazil and positive results were found in only two for deoxynivalenol and zearalenone.
Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Micotoxinas/análisis , Oryza/química , Plaguicidas/análisis , Espectrometría de Masas en Tándem/métodos , Brasil , Cromatografía Líquida de Alta Presión/normas , Reproducibilidad de los Resultados , Espectrometría de Masas en Tándem/normasRESUMEN
Epicotyls from germinated soybeans (EGS) have great potential as sources of endogenous ß-glucosidase. Furthermore, this enzyme may improve the conversion of isoflavones into their corresponding aglycones. ß-Glucosidase may also increase the release of aglycones from the cell wall of the plant materials. Therefore, the aim of this work was to optimize both the extraction of ß-glucosidase from EGS and to further examine its application in defatted soybean cotyledon to improve the recovery of aglycones, which were evaluated by ultra-high performance liquid chromatography (UHPLC). A multistep optimization was carried out and the effects of temperature and pH were investigated by applying a central composite design. The linear effect of pH and the quadratic effect of pH and temperature were significant for the extraction of ß-glucosidase and recovery aglycones, respectively. Optimum extraction of ß-glucosidase from EGS occurred at 30 °C and pH 5.0. Furthermore, the maximum recovery of aglycones (98.7%), which occurred at 35 °C and pH 7.0â»7.6 during 144 h of germination, increased 8.5 times with respect to the lowest concentration. The higher bioaccessibility of aglycones when compared with their conjugated counterparts is well substantiated. Therefore, the data provided in this contribution may be useful for enhancing the benefits of soybean, their products, and/or their processing by-products.
RESUMEN
A novel, simple, easy and cheap sample treatment strategy based on salting-out assisted liquid-liquid extraction for ochratoxin A (OTA) ultra-trace analysis in beer samples using ultra-high-performance liquid chromatography-tandem mass spectrometry determination was developed. The factors involved in the efficiency of pre-treatment were studied employing factorial design in the screening phase and the optimal conditions of the significant variables on the analytical response were evaluated using a central composite face-centred design. Consequently, the amount of salt ((NH4)2SO4), together with the volumes of sample, hydrophilic (acetone) and nonpolar (toluene) solvents, and times of vortexing and centrifugation were optimised. Under optimised conditions, the limits of detection and quantification were 0.02 µg l-1 and 0.08 µg l-1 respectively. OTA extraction recovery by SALLE was approximately 90% (0.2 µg l-1). Furthermore, the methodology was in agreement with EU Directive requirements and was successfully applied for analysis of beer samples.
Asunto(s)
Cerveza/análisis , Extracción Líquido-Líquido/métodos , Micotoxinas/análisis , Ocratoxinas/análisis , Cloruro de Sodio/química , Cromatografía Líquida de Alta Presión , Espectrometría de Masas en TándemRESUMEN
Cancer is one of the biggest problems in public health worldwide. Plants have been shown important role in anticancer research. Viscum album L. (Santalaceae), commonly known as mistletoe, is a semi-parasitic plant that grows on different host trees. In complementary medicine, extracts from European mistletoe (Viscum album L.) have been used in the treatment of cancer. The study was conducted to identify chemical composition and antitumor potential of Viscum album tinctures. Chemical analysis performed by high resolution chromatography equipped with high resolution mass spectrometer identified caffeic acid, chlorogenic acid, sakuranetin, isosakuranetin, syringenin 4-O-glucoside, syringenin 4-O-apiosyl-glucoside, alangilignoside C and ligalbumoside A compounds. Some of these compounds are probably responsible for the reduction of tumoral cellular growth in a dose-dependent manner. It was observed that melanoma murine cells (B16F10) were more sensitive to V. album tinctures than human leukaemic cells (K562), besides non-tumoral cells (MA-104) had a much lower cytotoxicity to them. Apoptotic-like cells were observed under light microscopy and were confirmed by a typical DNA fragmentation pattern. Additionally, flow cytometry results using Annexin-V/FITC permitted to quantify increased expression of early and late apoptotic markers on tumoral cells, confirming augmented Sub G0 population, which was probably associated with a consistent decrease in G1, and an increase in S or G2/M populations. Results indicate the chemical composition of V. album tinctures influences the mechanisms of in vitro tumoral cell death, suggesting a potential use in cancer pharmacotherapy research.
RESUMEN
A new analytical method for multiresidue determination of 16 multiclass pesticides in lettuce was developed using ultra-high performance liquid chromatography with tandem mass spectrometry with a triple quadrupole mass analyzer and positive mode electrospray ionization, using a previously optimized quick, easy, cheap, effective, rugged, and safe method for sample preparation. Validation studies, according to document SANTE/11945/2015, demonstrated that the developed method is selective, accurate, and precise, providing recoveries of 70-120%, relative standard deviations ≤20% and quantification limits from 3 µg/kg. The method was compared with one based on high-performance liquid chromatography with tandem mass spectrometry, in terms of chromatographic performance, detectability and matrix effect for five varieties of lettuce. The new method provided a reduction in the time for the chromatographic analysis of 50%, from 30 to 15 min, using a lower mobile phase flow rate (0.147 mL/min), which reduced the consumption of mobile phase by 25%, and injection of smaller amounts of sample (1.7 µL). Lower limits of quantification were obtained for almost all pesticides studied for green-leaf lettuce. However, in relation to the matrix effect, four of the five types of lettuce studied presented higher matrix effects.
Asunto(s)
Lactuca/química , Cromatografía Líquida de Alta Presión , Residuos de Plaguicidas/análisis , Espectrometría de Masas en TándemRESUMEN
This study aimed at evaluating the polycyclic aromatic hydrocarbons (PAHs) contamination of commercial vegetable oils and examined the identity through the fatty acids profiles. Coconut, safflower, evening primrose, and linseed oils marketed in São Paulo (Brazil) were investigated totaling 69 samples. Four PAHs, benzo[a]anthracene (BaA), chrysene (Chr), benzo[b]fluoranthene (BbF), and benzo[a]pyrene (BaP), were detected in 96% of the samples at individual levels ranging from not detected to 14.99⯵gâ¯kg-1. Chrysene was the abundant hydrocarbon found among all types of oils, with the highest median values. The results of the fatty acid profiles revealed that 43% showed different profiles according to the ones on their labels, with a higher incidence of adulteration of evening primrose oils. The maximum tolerable limits by European Regulation No. 835/2011 were exceeded for BaP in 12%, and for total 4 PAHs in 28%, with a greater contribution of adulterated samples.
Asunto(s)
Ácidos Grasos/análisis , Contaminación de Alimentos/análisis , Aceite de Linaza/análisis , Aceites de Plantas/análisis , Hidrocarburos Policíclicos Aromáticos/análisis , Brasil , Crisenos , Aceite de Coco/análisis , Análisis de los Alimentos , Ácidos Linoleicos/análisis , Oenothera biennis , Aceites de Plantas/química , Aceite de Cártamo/análisis , Ácido gammalinolénico/análisisRESUMEN
The novel alkaloid, oleracimine, presented remarkable anti-inflammatory bioactivity, and therefore, its pharmacokinetics was investigated in rat plasma after intravenous and oral administration by using a rapid ultra-high-performance liquid chromatography (UHPLC) method with UV detection at 270 nm. The analysis was performed on a shim-pack ODS column (75 mm×2 mm, 1.6 µm particle size, Shimadzu, Japan) column using isocratic elution with a mobile phase consisting of methanol-water (62:38, v/v) within 3 min. The results indicated that oleracimine was rapidly distributed with Tmax for 11.7 min after oral administration, which presented the double-peak phenomenon in the pharmacokinetic profile with a higher oral absolute bioavailability of 55.1% ± 7.83%.
Asunto(s)
Animales , Masculino , Ratas , Farmacocinética , Cromatografía Liquida/métodos , Portulaca/efectos adversos , Alcaloides/análisisRESUMEN
The present study aimed at investigating possible alterations in the serum lipid profile of euthymic patients with bipolar disorder type I (BD) compared to healthy controls (HC). Thirty-five individuals from both genders were recruited, with 14 diagnosed and treated as BD patients (BD group) and 21 healthy subjects (HC group). Clinical assessment was based on the Structured Clinical Interview for DSM-IV Axis I Disorders (SCID-I), Young Mania Rating Scale (YMRS), and 17-items of Hamilton Depression Rating Scale (HDRS-17) data, which were used to confirm diagnosis, to verify psychiatric comorbidities, and to estimate the severity of manic and depressive symptoms. Ultra-high performance liquid chromatography (UHPLC) coupled to high resolution mass spectrometry (HRMS) was applied to analyze the lipids extracted from all serum samples from both studied groups. In this pioneer and exploratory study, we observed different serum lipid profiles for BD and HC groups, especially regarding glycerophospholipid, glycerolipid, and sphingolipid distribution. Multivariate statistical analyses indicated that 121 lipids were significantly different between BD and HC. Phosphatidylinositols were identified as the most altered lipids in BD patient sera. The results of this preliminary study reinforce the role of lipid abnormalities in BD and offer additional methodological possibilities for investigation in the field.
Asunto(s)
Trastorno Bipolar/sangre , Lípidos/sangre , Espectrometría de Masas , Adulto , Trastorno Bipolar/diagnóstico , Trastorno Bipolar/psicología , Estudios de Casos y Controles , Comorbilidad , Depresión/sangre , Depresión/diagnóstico , Depresión/psicología , Manual Diagnóstico y Estadístico de los Trastornos Mentales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Fosfatidilinositoles/sangreRESUMEN
ABSTRACT Hydroxydihydrobovolide (HDB) was for the first time isolated from Portulaca oleracea L. and then its cytotoxicity against SH-SYTY cells was studied. Moreover, a rapid and sensitive ultra-high performance liquid chromatographic (UHPLC) method with bergapten as internal standard (IS) was developed and validated to investigate the pharmacokinetics of HDB in rats after intravenous and oral administrations of extract (POE). The UHPLC analysis was performed on a Diamonsil C18 analytical column, using acetonitrile-water (35:65, v/v) as the mobile phase with UV detection at 220 nm. The calibration curve was linear over the range of 0.2-25 µg/mL in rat plasma. The average extraction recovery was from 90.1 to 98.9%, and the relative standard deviations (RSDs) of the intra- and inter-day precisions were less than 4.7 and 4.1%, respectively. The results showed that 50 µM HDB had significant cytotoxicity on the SH-SY5Y cells, which was rapidly distributed with a Tmax of 11 min after oral administration and presented a low absolute bioavailability, 4.12%.
Asunto(s)
Animales , Masculino , Farmacocinética , Portulaca/clasificación , Extractos Vegetales/análisis , Cromatografía Líquida de Alta Presión/métodosRESUMEN
This paper focuses on the development of a novel miniaturized molecularly imprinted solid-phase extraction (MISPE) and ultra high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method to determine venlafaxine (VEN), O-desmethylvenlafaxine (ODV), and N-desmethylvenlafaxine (NDV) in plasma samples. The molecularly imprinted polymer (MIP) was prepared by the precipitation polymerization approach; VEN, metacrylic acid, ethylene glycol dimethacrylate, 2,2-azobisisobutyronitrile, and toluene were used as template, monomer, crosslinker, initiator, and porogen solvent, respectively. MIP and of the non-imprinted control polymer (NIP) sorbents were characterized by Fourier transform infrared spectroscopy and scanning electron microscopy. MIP phase presented higher extraction efficiency (MISPE, using plasma samples spiked with VEN) than the NIP phase (84 and 49% recovery rates, respectively). Analysis of other antidepressants with different chemical structures by MISPE-UHPLC-MS/MS attested to the selectivity of the developed MIP. The developed method presented precision assays with coefficients of variation (CV) smaller than 15%; accuracy assays with relative standard error (RSE%) values ranging from -12 to 16%, and linear ranges from 3 to 700ngmL(-1) for VEN, from 5 to 700ngmL(-1) for ODV, and from 3 to 500ngmL(-1) for NDV. The coefficients of determination (r(2)) were higher than 0.995. The lack-of-fit test also attested to the linearity of this method. This method was successfully applied to determine VEN, NDV, and ODV in plasma samples from depressed patients undergoing therapy with VEN.
Asunto(s)
Ciclohexanoles/sangre , Succinato de Desvenlafaxina/sangre , Impresión Molecular , Polímeros/química , Extracción en Fase Sólida/métodos , Espectrometría de Masas en Tándem/métodos , Clorhidrato de Venlafaxina/sangre , Acrilatos/química , Antidepresivos/sangre , Antidepresivos/química , Antidepresivos/uso terapéutico , Cromatografía Líquida de Alta Presión , Ciclohexanoles/metabolismo , Depresión/sangre , Depresión/tratamiento farmacológico , Succinato de Desvenlafaxina/metabolismo , Humanos , Metacrilatos/química , Microscopía Electrónica de Rastreo , Nitrilos/química , Polimerizacion , Espectroscopía Infrarroja por Transformada de Fourier , Tolueno/química , Clorhidrato de Venlafaxina/metabolismo , Clorhidrato de Venlafaxina/farmacocinética , Clorhidrato de Venlafaxina/uso terapéuticoRESUMEN
A new molecularly imprinted polymer modified with restricted access material (a hydrophilic external layer), (MIP-RAM) was synthesized via polymerization in situ in an open fused silica capillary. This stationary phase was used as sorbent for in-tube solid phase microextraction (in-tube SPME) to determine parabens in breast milk samples by ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). Scanning electron micrographs (SEM) illustrate MIP surface modification after glycerol dimethacrylate (hydrophilic monomer) incorporation. The interaction between parabens and MIP-RAM was investigated by Fourier-transform infrared (FTIR) spectroscopy. The Scatchard plot for MIP-RAM presented two linear parts with different slopes, illustrating binding sites with high- and low-affinity. Endogenous compounds exclusion from the MIP-RAM capillary was demonstrated by in-tube SPME/LC-UV assays carried out with blank milk samples. The in-tube SPME/UHPLC-MS/MS method presented linear range from 10 ng mL(-1) (LLOQ) to 400 ng mL(-1) with coefficients of determination higher than 0.99, inter-assay precision with coefficient of variation (CV) values ranging from 2 to 15%, and inter-assay accuracy with relative standard deviation (RSD) values ranging from -1% to 19%. Analytical validation parameters attested that in-tube SPME/UHPLC-MS/MS is an appropriate method to determine parabens in human milk samples to assess human exposure to these compounds. Analysis of breast milk samples from lactating women demonstrated that the proposed method is effective.
Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Leche Humana/química , Parabenos/análisis , Parabenos/aislamiento & purificación , Polímeros/síntesis química , Microextracción en Fase Sólida/métodos , Espectrometría de Masas en Tándem/métodos , Adsorción , Cromatografía Líquida de Alta Presión/instrumentación , Femenino , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Lactancia , Impresión Molecular , Parabenos/química , Polimerizacion , Polímeros/química , Dióxido de Silicio/química , Microextracción en Fase Sólida/instrumentación , Espectrometría de Masas en Tándem/instrumentaciónRESUMEN
Nevirapine (NVP), a non-nucleoside reverse transcriptase inhibitor, is a drug widely used in the treatment of Acquired Immunodeficiency Syndrome (AIDS). The evaluation of NVP stability is of fundamental importance in order to guarantee drug product efficacy, safety and quality. In this study, NVP active pharmaceutical ingredient (API) and tablets were subjected to a detailed study of forced degradation, employing several degrading agents (acid, alkaline, water, metal ions, humidity, heat, light and oxidation agents). In order to determine NVP and the degradation products formed, a stability-indicating UHPLC method using fused core column was developed and validated. The separation was carried out using a Poroshell 120C18 column (100×2.1mm i.d.; 2.7µm particle size) and the mobile phase was composed of acetonitrile and water in a gradient elution, at a flow rate of 0.2ml/min. Chemical structures and mechanisms for the formation of three degradation products were proposed by means of LC/MS-MS. Also, NVP degradation kinetic was studied and its order of degradation evaluated. NVP was degraded in acidic and oxidative conditions and the degradation profile for NVP tablets and API were similar. The stability-indicating method proved to be selective for NVP and its degradation products. Calibration curve was linear in the range of 8-48µg/ml and the method showed to be precise, accurate and robust for both NVP API and tablets, with detection and quantification limits of 0.092µg/ml and 0.174µg/ml, respectively.