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Soybean crop is regulated by abiotic and biotic stresses with great potential in reducing grain yield and quality. The selection of resistant cultivars is a promising approach for mitigating these damages. We evaluated the chemical profile of Glycine max leaves from different cultivars in order to explore their defense mechanisms against Spodoptera cosmioides caterpillars. We optimized solid-liquid extraction techniques using ultrasound bath and static headspace extraction. Additionally, we developed an approach based on liquid and gas chromatography for analyzing the chemical profile of G. max cultivars. The principal component analysis allowed the classification of transgenic cultivars, which are classified as susceptible to S. cosmioides, from those obtained by genetic improvement and resistant to the insect. Differences were observed in the abundance of phenolic glycosides, lipids, aldehydes, and alcohols. More specifically, S. cosmioides resistant cultivars presented molecules related to the jasmonic and salicylic acid pathways. Such data can contribute to a molecular understanding of phenotypic diversity in soybean cultivars, from plant quality to resistance mechanisms and adaptation, to environmental stress and herbivory.
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High-temperature exposure during hot melt extrusion processing of amorphous solid dispersions may result in thermal degradation of the drug. Polymer type may influence the extent of degradation, although the underlying mechanisms are poorly understood. In this study, the model compound, ritonavir (Tm = 126 °C), undergoes thermal degradation upon high-temperature exposure. The extent of degradation of ritonavir in amorphous solid dispersions (ASDs) formulated with poly(vinylpyrrolidone) (PVP), poly(vinylpyrrolidone) vinyl acetate copolymer (PVP/VA), hydroxypropyl methylcellulose acetate succinate (HPMCAS), and hydroxypropyl methylcellulose (HPMC) following isothermal heating and hot melt extrusion was evaluated, and mechanisms related to molecular mobility and intermolecular interactions were assessed. Liquid chromatography-mass spectrometry (LC-MS/MS) studies were used to determine the degradation products and pathways and ultimately the drug-polymer compatibility. The dominant degradation product of ritonavir was the result of a dehydration reaction, which then catalyzed a series of hydrolysis reactions to generate additional degradation products, some newly reported. This reaction series led to accelerated degradation rates with protic polymers, HPMCAS and HPMC, while ASDs with aprotic polymers, PVP and PVP/VA, had reduced degradation rates. This work has implications for understanding mechanisms of thermal degradation and drug-polymer compatibility with respect to the thermal stability of amorphous solid dispersions.
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Composición de Medicamentos/métodos , Polímeros , Ritonavir/química , Cromatografía Líquida de Alta Presión , Liberación de Fármacos , Tecnología de Extrusión de Fusión en Caliente/métodos , Ritonavir/administración & dosificación , Espectrofotometría Infrarroja , TermogravimetríaRESUMEN
Forced degradation tests are studies used to assess the stability of active pharmaceutical ingredients (APIs) and their formulations. These tests are performed submitting the API under extreme conditions in order to know the main degradation products in a short period of time. The results of these studies are used to assess the degradation susceptibility of APIs and to validate chromatographic analytical methods. However, most of degradation studies are performed using one-factor-at-the-time (OFAT) which does not consider the interactions between degradation variables. This work proposes the use of Design of Experiment (DoE) approach in forced degradation of albendazole (ABZ). It was used a central composite design (CCD) to evaluate the forced degradation in a multivariate way. Experiments were performed taking into account the variables pH, temperature, oxidizing agent (H2O2) and UV radiation. It was verified the influence of the variables and their interactions on the ABZ degradation. The ABZ oxidation showed to be the main degradation route for ABZ, which is strongly influenced by the temperature. The hydrolysis was relevant at alkaline medium and high temperature. LC-IT-MSn was used to identify the degradation products. It was found three known degradation products (albendazole-2-amino, albendazole sulfoxide and albendazole sulfone) and a new derivate of albendazole molecule (albendazole sulfoxide with a chlorine). This last one was isolated and characterized by UPLC-QToF-MS and NMR analyses.
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Antihelmínticos , Preparaciones Farmacéuticas , Albendazol , Cromatografía Liquida , Composición de Medicamentos , Peróxido de HidrógenoRESUMEN
New antifungals are increasingly needed due to the emergence of resistant fungal strains. Traditional antifungal assays are laborious and require significant amounts of samples. The present work presents a new proposal to evaluate antifungal activity and antagonism among fungal species, based on experiments of fungal culture and co-culture, 1H NMR profile of fungal culture extracts and chemometrics. In order to develop the work, six axenic cultures of fungi that infested fruits (Fusarium guttiforme, Pestalotiopsis diospyri, Phoma caricae-papayae, Colletotrichum horii, Phytophthora palmivora, and C. gloeosporioides), and co-cultures of all possible combination among them were performed (totalizing 63 experiments). All fungal extracts were evaluated by 1H NMR followed by Principal Component Analyses (PCA) in order to determine spectral dissimilarity among the extracts. Results showed that 1H NMR data evaluated by PCA were capable to predict both antagonism and antifungal activity. Traditional antifungal in vitro assays of active and inactive extracts were also performed in order to prove the prediction made by PCA. The obtained data showed that the approach is an outstanding tool to simultaneously obtain and evaluate bioactive compounds because: it was able to predict the activity of five different extracts in a collection of sixty-three, which would be much more difficult and time consuming if applied randomly; most important antifungal extracts are indicated by PCA; hundreds of traditional in vitro assays are avoid; and, the method is very time and money saving.
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Antifúngicos/farmacología , Hongos/efectos de los fármacos , Espectroscopía de Resonancia Magnética , Técnicas de Cocultivo , Técnicas de Cultivo , Hongos/clasificación , Pruebas de Sensibilidad Microbiana , Análisis de Componente PrincipalRESUMEN
Ethanolic extracts of propolis are consumed for their health benefits even though direct consumption of alcoholic extracts is not always ideal. Natural Deep Eutectic Solvents (NADES) can potentially extract similar compounds as alcoholic extracts while being better for direct consumption. Therefore, in this work alternative solvents for the extraction of green propolis including its biomarker artepillin C were examined. Sixteen NADES made from low toxicity chemicals, including the essential amino acid l-lysine, were explored along with twelve individual NADES components and honey, which showed similar physical-chemical properties to NADES. At 50⯰C NADES made from choline chloride-propylene glycol or lactic acid proved to be equal or better than the benchmark EtOH:Water 7:3 (v/v). Alternatively, aqueous l-lysine appeared as a potential solvent for the preparation of aqueous propolis extracts. From these findings NADES, honey and aqueous l-lysine solutions all demonstrated the potential to replace ethanol or water for extracting green propolis.
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Colina/química , Lisina/química , Extractos Vegetales/química , Própolis/química , Propilenglicol/química , Solventes/química , Agua/química , Colina/análisis , Cromatografía Líquida de Alta Presión/métodos , Lisina/análisis , Extractos Vegetales/análisis , Própolis/análisis , Propilenglicol/análisis , Solventes/análisis , Agua/análisisRESUMEN
ABSTRACT Concepts of sustainability have received attention from people involved in investigation of nature-derived matrices. The effects of concomitant pollutant activities are cumulative and harmful to the environment from which these matrices are obtained. High performance liquid chromatography analyses generate millions of litters of chemical waste worldwide every year. Reduction of organic solvent consumption during the analyses and replacement of harmful solvents with greener options are the main approaches to mitigate this problem. This work explored the strategy of employing monolithic columns when the problematic acetonitrile is intended to be replaced with the greener but more viscous ethanol in fingerprinting a leaf extract of Lippia sidoides Cham., Verbenaceae, by high performance liquid chromatography. Two monolithic columns were coupled in series to test a more critical backpressure condition while doubling the number of theoretical plates, which can be useful to separate the hundreds of compounds present in plant extracts. All work was conducted by employing design of experiments. A mathematical model indicated an optimum point in which ethanol was the only organic solvent of the mobile phase. However, the use of a proper metric, which considered environmental parameters together with separation parameters, evidenced that an experimental condition of the original central composite design should be preferred over the former even if containing 20% acetonitrile in the organic modifier mixture. Flow rates of up to 3 ml/min were accommodated with two coupled monolithic columns without exceeding 250 bar. These findings reinforced that no state-of-the-art instruments are needed to shift from traditional harmful solvents to greener ones, but only require a shift in researchers' approach toward sustainability.
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The aim of this work was to quantify B-complex vitamins in pharmaceutical samples by surface enhanced Raman spectroscopy technique using gold colloid substrate. Synthesis of gold nanoparticles was performed according to an adapted Turkevich method. Initial essays were able to suggest the orientation of molecules on gold nanoparticles surface. Central Composite design was performed to obtain the highest SERS signal for nicotinamide and riboflavin. The evaluated parameters in the experimental design were volume of AuNPs, concentration of vitamins and sodium chloride concentration. The best condition for nicotinamide was NaCl 2.3×10-3molL-1 and 700µL of AuNPs colloid and this same condition showed to be adequate to quantify thiamine. The experimental design for riboflavin shows the best condition at NaCl 1.15×10-2molL-1 and 2.8mL of AuNPs colloid. It was possible to quantify thiamine and nicotinamide in presence of others vitamins and excipients in two solid multivitamin formulations using the standard addition procedure. The standard addition curve presented a R2 higher than 0.96 for both nicotinamide and thiamine, at orders of magnitude 10-7 and 10-8molL-1, respectively. The nicotinamide content in a cosmetic gel sample was also quantified by direct analysis presenting R2 0.98. The t-student test presented no significant difference regarding HPLC method. Despite the experimental design performed for riboflavin, it was not possible its quantification in the commercial samples.
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Composición de Medicamentos , Espectrometría Raman , Complejo Vitamínico B/análisis , Concentración de Iones de Hidrógeno , Estándares de Referencia , Propiedades de Superficie , ComprimidosRESUMEN
The occurrence, partitioning, and spatio-temporal distribution of seven pharmaceuticals for human use, three steroid hormones and one personal care product were determined in surface water, suspended particulate matter (SPM), and sediment of Piraí Creek and Jundiaí River (Jundiaí River Basin, São Paulo, Brazil). The maximum average detected concentrations of the compounds in the Piraí River samples were < 30 ng L-1, except for caffeine (222 ng L-1). In Jundiaí River samples, most of the compounds were frequently detected, wherein caffeine had the highest concentration, with maximum average concentrations of 14,050 ng L-1, followed by atenolol (431 ng L-1), ibuprofen (268 ng L-1) and diclofenac (214 ng L-1). Atenolol, propranolol, estrone, and triclosan were the contaminants most frequently detected in sediment and SPM samples. Triclosan had the highest average proportion of SPM as opposed to in the aqueous phase (> 75%). Contaminants with acid functional groups showed, in general, a lower tendency to bind to particulate matter and sediments. In addition, hydrophobicity had an important effect on their environmental partitioning. The spatial distribution of contaminants along the Jundiaí River was mainly affected by the higher concentration of contaminants in water samples collected downstream from a sewage treatment plant (STP). The results obtained here clearly showed the importance of the analysis of some contaminants in the whole water, meaning both dissolved and particulate compartments in the water, and that the partitioning is ruled by a set of parameters associated to the physicochemical characteristics of contaminants and the matrix properties of the studied, which need be considered in an integrated approach to understand the fate of emerging chemical contaminants in aquatic environments.
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Cafeína/análisis , Monitoreo del Ambiente/métodos , Sedimentos Geológicos/química , Ríos/química , Triclosán/análisis , Contaminantes Químicos del Agua/análisis , Brasil , Humanos , Material Particulado/químicaRESUMEN
A major challenge in metabolomic studies is how to extract and analyze an entire metabolome. So far, no single method was able to clearly complete this task in an efficient and reproducible way. In this work we proposed a sequential strategy for the extraction and chromatographic separation of metabolites from leaves Jatropha gossypifolia using a design of experiments and partial least square model. The effect of 14 different solvents on extraction process was evaluated and an optimized separation condition on liquid chromatography was estimated considering mobile phase composition and analysis time. The initial conditions of extraction using methanol and separation in 30 min between 5 and 100% water/methanol (1:1 v/v) with 0.1% of acetic acid, 20 µL sample volume, 3.0 mL min(-1) flow rate and 25°C column temperature led to 107 chromatographic peaks. After the optimization strategy using i-propanol/chloroform (1:1 v/v) for extraction, linear gradient elution of 60 min between 5 and 100% water/(acetonitrile/methanol 68:32 v/v with 0.1% of acetic acid), 30 µL sample volume, 2.0 mL min(-1) flow rate, and 30°C column temperature, we detected 140 chromatographic peaks, 30.84% more peaks compared to initial method. This is a reliable strategy using a limited number of experiments for metabolomics protocols.
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Jatropha/metabolismo , Metaboloma , Metabolómica/métodos , Hojas de la Planta/metabolismo , Cromatografía Líquida de Alta Presión , Jatropha/química , Análisis de los Mínimos Cuadrados , Modelos Moleculares , Extractos Vegetales/química , Extractos Vegetales/metabolismo , Hojas de la Planta/químicaRESUMEN
Ezetimibe (EZT), in its anhydrous form, is a drug used for cholesterol and lipids reduction in blood plasma. The presence of EZT monohydrate in commercial tablets can change the solubility rate of the API, decreasing its activity. The objective of this work was to verify if the humidity present in the excipients could promote the phase transition from EZT anhydrous to hydrate. Initially the stability of the pure anhydrous form was monitored by Raman, at room temperature (23°C) and relative humidity (75%). The MCR-ALS method showed that almost all EZT changed to hydrated form in 30 min. Then tablets of ezetimibe in the presence of its excipients were prepared and vacuum packed using a polyethylene film. Such tablet was monitored by Raman spectroscopy for 24h in order to quantify the mixture of the crystalline forms. A multivariate calibration model using Raman spectroscopy and Partial Least Square (PLS) regression was built, with validation and cross validation errors around 0.6% (wt/wt), for both crystalline forms, and R(2) higher than 0.96. The PLS model was used to quantify the crystalline mixture of ezetimibe in the monitored tablet, after 24h more than 70% of ezetimibe changed to the hydrated form.
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Excipientes/química , Ezetimiba/química , Calibración , Química Farmacéutica/métodos , Cristalización , Estabilidad de Medicamentos , Humedad , Análisis de los Mínimos Cuadrados , Transición de Fase , Solubilidad , Espectrometría Raman/métodos , Comprimidos/química , TemperaturaRESUMEN
Sediments are the fate of several emerging organic contaminants, such as pharmaceuticals, personal care products and hormones, and therefore an important subject in environmental monitoring studies. In the present work, a simple and sensitive method was developed, validated and applied for the simultaneous extraction of atenolol, caffeine, carbamazepine, diclofenac, ibuprofen, naproxen, propranolol, triclosan, estrone, 17-ß-estradiol and 17-α-ethinylestradiol using ultrasound-assisted extraction from freshwater sediment samples followed by solid-phase extraction clean-up and liquid chromatography with tandem mass spectrometry detection. The solvent type and extraction pH were evaluated to obtain the highest recoveries of the compounds. The best method shows absolute recoveries between 54.0 and 94.4% at 50 ng/g concentration. The method exhibits good precision with relative standard deviation ranging from 1.0-16%. The detection and quantification limits ranged from 0.006-0.067 and 0.016-0.336 ng/g, respectively. The developed method was successfully applied to freshwater sediment samples collected from different sites in Jundiaí River basin of São Paulo State, Brazil. The compounds atenolol, caffeine, propranolol and triclosan were detected in all the sampling sites with concentrations of 13.8, 41.0, 28.5 and 176 ng/g, respectively.
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Fraccionamiento Químico/métodos , Agua Dulce/química , Sedimentos Geológicos/química , Contaminantes Químicos del Agua/análisis , Brasil , Cromatografía Liquida/métodos , Monitoreo del Ambiente/métodos , Humanos , Concentración de Iones de Hidrógeno , Ríos/química , Extracción en Fase Sólida/métodos , Solventes , Espectrometría de Masas en Tándem/métodos , UltrasonidoRESUMEN
INTRODUCTION: Bauhinia forficata Link. is recognised by the Brazilian Health Ministry as a treatment of hypoglycemia and diabetes. Analytical methods are useful to assess the plant identity due the similarities found in plants from Bauhinia spp. HPLC-UV/PDA in combination with chemometric tools is an alternative widely used and suitable for authentication of plant material, however, the shifts of retention times for similar compounds in different samples is a problem. OBJECTIVE: To perform comparisons between the authentic medicinal plant (Bauhinia forficata Link.) and samples commercially available in drugstores claiming to be "Bauhinia spp. to treat diabetes" and to evaluate the performance of multivariate curve resolution - alternating least squares (MCR-ALS) associated to principal component analysis (PCA) when compared to pure PCA. METHODOLOGY: HPLC-UV/PDA data obtained from extracts of leaves were evaluated employing a combination of MCR-ALS and PCA, which allowed the use of the full chromatographic and spectrometric information without the need of peak alignment procedures. RESULTS: The use of MCR-ALS/PCA showed better results than the conventional PCA using only one wavelength. Only two of nine commercial samples presented characteristics similar to the authentic Bauhinia forficata spp., considering the full HPLC-UV/PDA data. CONCLUSION: The combination of MCR-ALS and PCA is very useful when applied to a group of samples where a general alignment procedure could not be applied due to the different chromatographic profiles. This work also demonstrates the need of more strict control from the health authorities regarding herbal products available on the market.
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Bauhinia/química , Cromatografía Líquida de Alta Presión/métodos , Preparaciones de Plantas/análisis , Análisis de Componente Principal/métodos , Espectrofotometría Ultravioleta/métodos , Análisis por Conglomerados , Análisis de los Mínimos Cuadrados , Análisis Multivariante , Hojas de la Planta/química , Preparaciones de Plantas/clasificación , Preparaciones de Plantas/normas , Vigilancia de Productos Comercializados/métodos , Vigilancia de Productos Comercializados/normas , Estándares de Referencia , Reproducibilidad de los ResultadosRESUMEN
A considerable amount of chemical waste from liquid chromatography analysis is generated worldwide. Acetonitrile is the most employed solvent in liquid chromatography analyses since it exhibits favorable physicochemical properties for separation and detection, but it is an unwelcome solvent from an environmental point of view. Acetone might be a much greener alternative to replace acetonitrile in reversed-phase liquid chromatography, since both share similar physicochemical properties, but its applicability with ultraviolet absorbance-based detectors is limited. In this work, a reference method using acetonitrile and high-performance liquid chromatography coupled to an ultraviolet photodiode array detector coupled to a corona charged aerosol detector system was developed to fingerprint a complex sample. The possibility of effectively substituting acetonitrile with acetone was investigated. Design of experiments was adopted to maximize the number of peaks acquired in both fingerprint developments. The methods with acetonitrile or acetone were successfully optimized and proved to be statistically similar when only the number of peaks or peak capacity was taken into consideration. However, the superiority of the latter was evidenced when parameters of separation and those related to greenness were heuristically combined. A green, comprehensive, time- and resource-saving approach is presented here, which is generic and applicable to other complex matrices. Furthermore, it is in line with environmental legislation and analytical trends.
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In this work, filter paper was used as a low cost substrate for silver nanoparticles in order to perform the detection and quantification of acetylsalicylic acid by SERS in a commercial tablet. The reaction conditions were 150mM of ammonium hydroxide, 50mM of silver nitrate, 500mM of glucose, 12min of the reaction time, 45°C temperature, pretreatment with ammonium hydroxide and quantitative filter paper (1-2µm). The average size of silver nanoparticles deposited on the paper substrate was 180nm. Adsorption time of acetylsalicylic acid on the surface of the silver-coated filter paper was studied and an adsorption time of 80min was used to build the analytical curve. It was possible to obtain a calibration curve with good precision with a coefficient of determination of 0.933. The method proposed in this work was capable to quantify acetylsalicylic acid in commercial tablets, at low concentration levels, with relative error of 2.06% compared to the HPLC. The preparation of filter paper coated with silver nanoparticles using Tollen's reagent presents several advantages such as low cost of synthesis, support and reagents; minimum amount of residuals, which are easily treated, despite the SERS spectroscopy presenting fast analysis, with low sample preparation and low amount of reactants as in HPLC analysis.
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Antiinflamatorios no Esteroideos/análisis , Aspirina/análisis , Filtración/métodos , Nanopartículas del Metal/química , Plata/química , Espectrometría Raman/métodos , Adsorción , Límite de Detección , Nanopartículas del Metal/ultraestructura , Modelos Moleculares , Papel , ComprimidosRESUMEN
The use of chemical markers of undoubted anthropogenic sources for surface freshwater contamination by wastewaters was evaluated employing correlations observed between measured physico-chemical parameters as the electrical conductivity and the concentration of different emerging organic compounds. During the period from April/2011 to April/2012 spatial-temporal variations and contamination patterns of two rivers (Piraí and Jundiaí rivers), São Paulo state, Brazil were evaluated. Seven physico-chemical parameters and concentrations of different classes of emerging contaminants were determined in samples collected in seven field campaigns. The high linear correlation coefficients obtained for the compounds diclofenac (r=0.9085), propanolol (r=0.8994), ibuprofen (r=0.8720) and atenolol (r=0.7811) with electrical conductivity, also corroborated by principal component analysis (PCA), point to the potential use of these compounds as markers of investigated surface water contamination by wastewaters. Due to specific inputs, these environmental markers showed very good effectiveness for the identification and differentiation of water body contamination by discharges of treated and untreated urban sewage.
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Conductividad Eléctrica , Monitoreo del Ambiente/métodos , Agua Dulce/química , Aguas Residuales/análisis , Contaminantes Químicos del Agua/química , Brasil , Aguas Residuales/química , Contaminantes Químicos del Agua/análisisRESUMEN
Supported silver nanoparticles on filter paper were synthesized using Tollens' reagent. Experimental designs were performed to obtain the highest SERS enhancement factor by study of the influence of the parameters: filter paper pretreatment, type of filter paper, reactants concentration, reaction time and temperature. To this end, fractional factorial and central composite designs were used in order to optimize the synthesis for quantification of nicotinamide in the presence of excipients in a commercial sample of cosmetic. The values achieved for the optimal condition were 150 mM of ammonium hydroxide, 50 mM of silver nitrate, 500 mM of glucose, 8 min for the reaction time, 45 °C temperature, pretreatment with ammonium hydroxide and quantitative filter paper (1-2 µm). Despite the variation of SERS intensity, it was possible to use an adapted method of internal standard to obtain a calibration curve with good precision. The coefficient of determination of the linear fit was 0.97. The method proposed in this work was capable of quantifying nicotinamide on a commercial cosmetic gel, at low concentration levels, with a relative error of 1.06% compared to the HPLC. SERS spectroscopy presents faster analyses than HPLC, also complex sample preparation and large amount of reactants are not necessary.
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Cosméticos/análisis , Nanopartículas del Metal/química , Niacinamida/análisis , Papel , Plata/química , Espectrometría Raman/métodos , Filtración , Propiedades de SuperficieRESUMEN
In the present work the homogeneity of a pharmaceutical formulation presented as a cream was studied using infrared imaging spectroscopy and chemometric methodologies such as principal component analysis (PCA) and multivariate curve resolution with alternating least squares (MCR-ALS). A cream formulation, presented as an emulsion, was prepared using imiquimod as the active pharmaceutical ingredient (API) and the excipients: water, vaseline, an emulsifier and a carboxylic acid in order to dissolve the API. After exposure at 45°C during 3 months to perform accelerated stability test, the presence of some crystals was observed, indicating homogeneity problems in the formulation. PCA exploratory analysis showed that the crystal composition was different from the composition of the emulsion, since the score maps presented crystal structures in the emulsion. MCR-ALS estimated the spectra of the crystals and the emulsion. The crystals presented amine and C-H bands, suggesting that the precipitate was a salt formed by carboxylic acid and imiquimod. These results indicate the potential of infrared imaging spectroscopy in conjunction with chemometric methodologies as an analytical tool to ensure the quality of cream formulations in the pharmaceutical industry.
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Aminoquinolinas/análisis , Análisis de Componente Principal , Crema para la Piel/análisis , Aminoquinolinas/química , Imiquimod , Análisis de los Mínimos Cuadrados , Análisis Multivariante , Espectrofotometría Infrarroja , Espectroscopía Infrarroja CortaRESUMEN
Co-crystals are multicomponent substances designed by the addition of two or more different molecules in a same crystallographic pattern, in which it differs from the crystallographic motif of its co-formers. The addition of highly soluble molecules, like nicotinamide, in the crystallographic pattern of ibuprofen enhances its solubility more than 7.5 times, improving the properties of this widely used drug. Several analytical solid state techniques are used to characterize the ibuprofen-nicotinamide co-crystal, being the most used: mid-infrared (ATR-FTIR), differential scanning calorimetry (DSC), X-ray diffraction (XRPD) and Raman spectroscopy. These analytical solid state techniques were evaluated to quantify a mixture of ibuprofen-nicotinamide co-crystal and its co-formers in order to develop a calibration model to evaluate the co-crystal purity after its synthesis. Raman spectroscopy showed better result than all other techniques with a combination of multivariate calibration tools, presenting lower values of calibration and prediction errors. The partial least squares regression model gave a mean error lower than 5% for all components presented in the mixture. DSC and mid-infrared spectroscopy proved to be insufficient for quantification of the ternary mixture. XRPD presented good results for quantification of the co-formers, ibuprofen and nicotinamide, but fair results for the co-crystal. This is the first report of quantification of ibuprofen-nicotinamide co-crystal, among its co-formers. The quantification is of great importance to determine the yield of the co-crystallization reactions and the purity of the product obtained.
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Ibuprofeno/química , Niacinamida/química , Calibración , Rastreo Diferencial de Calorimetría/métodos , Química Farmacéutica/métodos , Cristalización/métodos , Cristalografía por Rayos X/métodos , Análisis de los Mínimos Cuadrados , Difracción de Polvo/métodos , Solubilidad , Espectroscopía Infrarroja Corta/métodos , Espectrometría Raman/métodos , Tecnología Farmacéutica/métodos , Difracción de Rayos X/métodosRESUMEN
A chromatographic fingerprint is a comprehensive method that reveals the distinctive pattern of peaks across the chromatogram for a given sample. It is considered an effective strategy to assess the identity and quality of herbal materials, as well as for the control of the quality of their derived products. HPLC is the most employed technique for these purposes and it is used routinely for quality control in industry. Hence, its impact on the environment should not be neglected. This work provides a rational and generic procedure to qualitatively fingerprint complex matrices. Resource- and time-saving experimental designs were selected; an alternative safer organic solvent was tested and a time-saving and innovative response entitled the green chromatographic fingerprinting response was developed and employed. This procedure was applied in the development of chromatographic fingerprints for extracts of Bauhinia forficata and Casearia sylvestris. Moreover, the response proposed here can be combined with a complementary metric available in the literature to compare methods using different solvents. According to this, the chromatographic fingerprints developed here using ethanol as the organic solvent provided a performance better than that of reference methods in which more harmful acetonitrile or methanol were employed.
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Bauhinia/química , Casearia/química , Cromatografía Líquida de Alta Presión/métodos , Tecnología Química Verde/métodos , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Extracción en Fase Sólida/métodos , Bauhinia/metabolismo , Casearia/metabolismo , Metaboloma , Extractos Vegetales/metabolismoRESUMEN
The Lippia genus is used in ethnobotany as food, beverages, seasoning and antiseptic remedies, among others. The chemical compositions of fifteen extracts of six Lippia species were investigated comparatively by HPLC-PDA. To avoid data replication of previous works on this genus, Lippia lupulina Cham. root ethanol extract was selected for isolation procedures based on Principal Component Analyses (PCA) of such data. Seven compounds previously unreported in this genus were isolated from this extract (a triterpene, two furanonaphtoquinones, a furanochromone, an isoflavone, a stilbene and an iridoid). The activities of extracts, fractions and pure compounds towards Candida albicans, Candida krusei, Candida parapsilosis and Cryptococcus neoformans were investigated. Two fractions from the extract of Lippia salviaefolia leaves showed marked inhibition of fungal growth, in addition to verbascoside and asebogenin, which showed MICs lower than 15.6µg/ml and may be promising leads for the development of new antifungal agents, especially against C. neoformans.