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1.
Eur J Pharm Sci ; 127: 330-338, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-30445224

RESUMO

Mebendazole (MBZ), designated as a WHO essential drug, can exist in diverse solid forms and presents low absorption at the gastrointestinal level. Considering the potential of cyclodextrins to enhance the solubility and permeability of drugs, inclusion complexes of polymorphs A and C of MBZ with ß­cyclodextrin were obtained. The characterization of the complexes in solid state was performed by using a combination of experimental techniques including Fourier transform infrared spectroscopy, powder X-ray diffractometry and solid state nuclear magnetic resonance. Moreover, the effect of the binary complexes on their physical stability was evaluated. In addition, for a complete characterization of polymorphs A and C, one dimensional spectra and correlation nuclear magnetic resonance experiments were employed. Our physical studies showed that the inclusion complexes were new crystalline forms that induced shifts and broadening in the infrared and nuclear spectra. A molecular modelling analysis performed on the inclusion modes, demonstrated that the most favourable structure for the complex was the head down orientation. Moreover, the intermolecular interactions calculated for the complex with the atoms in molecules theory are in good agreement with the spectroscopic results. The inclusion complexes exhibited an increment of solubility in simulated physiological media. Furthermore, it was demonstrated that the complex formation did not affect the physical stability of the polymorphs.


Assuntos
Anti-Helmínticos/química , Mebendazol/química , beta-Ciclodextrinas/química , Cristalização , Modelos Moleculares
2.
J Pharm Biomed Anal ; 149: 225-233, 2018 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-29126084

RESUMO

In this work, a novel molecularly imprinted polymer (MIP) proposed as solid phase extraction sorbent was developed for the determination of propylparaben (PP) in diverse cosmetic samples. The use of parabens (PAs) is authorized by regulatory agencies as microbiological preservative; however, recently several studies claim that large-scale use of these preservatives can be a potential health risk and harmful to the environment. Diverse factors that influence on polymer synthesis were studied, including template, functional monomer, porogen and crosslinker used. Morphological characterization of the MIP was performed using SEM and BET analysis. Parameters affecting the molecularly imprinted solid phase extraction (MISPE) and elution efficiency of PP were evaluated. After sample clean-up, the analyte was analyzed by high performance liquid chromatography (HPLC). The whole procedure was validated, showing satisfactory analytical parameters. After applying the MISPE methodology, the extraction recoveries were always better than 86.15%; the obtained precision expressed as RSD% was always lower than 2.19 for the corrected peak areas. Good linear relationship was obtained within the range 8-500ngmL-1 of PP, r2=0.99985. Lower limits of detection and quantification after MISPE procedure of 2.4 and 8ngmL-1, respectively were reached, in comparison with previously reported methodologies. The development of MISPE-HPLC methodology provided a simple an economic way for accomplishing a clean-up/preconcentration step and the subsequent determination of PP in a complex matrix. The performance of the proposed method was compared against C-18 and silica solid phase extraction (SPE) cartridges. The recovery factors obtained after applying extraction methods were 96.6, 64.8 and 0.79 for MISPE, C18-SPE and silica-SPE procedures, respectively. The proposed methodology improves the retention capability of SPE material plus robustness and possibility of reutilization, enabling it to be used for PP routine monitoring in diverse personal care products (PCP) and environmental samples.


Assuntos
Cosméticos/análise , Impressão Molecular/métodos , Parabenos/análise , Polímeros/química , Águas Residuárias/análise , Cromatografia Líquida de Alta Pressão/instrumentação , Cromatografia Líquida de Alta Pressão/métodos , Cosméticos/toxicidade , Monitoramento Ambiental/instrumentação , Monitoramento Ambiental/métodos , Impressão Molecular/instrumentação , Parabenos/toxicidade , Dióxido de Silício/química , Extração em Fase Sólida/instrumentação , Extração em Fase Sólida/métodos , Águas Residuárias/toxicidade
3.
Dominguezia ; 30(1): 35-40, 2014. tab, graf
Artigo em Espanhol | MOSAICO - Saúde integrativa, LILACS | ID: biblio-1005882

RESUMO

Diversas especies de Passiflora L. (Passifloraceae) son usadas en medicina tradicional en el tratamiento de la ansiedad, el insomnio y otros trastornos nerviosos. De ellas han sido aisladas varias C-glicosilflavonas. En este trabajo se determinó la presencia de C-glicosilflavonas en Passiflora caerulea L. y P. foetida L., por medio de HPLC y se utilizó FTIR en forma comparativa, con el objeto de hacer un aporte al control de calidad y caracterizar los extractos acuoso y metanólico de ambas especies. Los cromatogramas de HPLC de ambos extractos mostraron tiempos de retención característicos a 12,10 min (vitexina), 17,94 min (isovitexina), 19,93 min (orientina) y 25,11 min (isoorientina), con espectros UV característicos. P. caerulea presentó las cuatro C-glicosilflavonas mencionadas, mientras que P. foetida careció solo de isoorientina en el extracto acuoso y únicamente presentó vitexina e isovitexina en el extracto metanólico. En la zona de la "huella dactilar" de los perfiles FTIR se observaron diferencias cualitativas sustanciales. P. foetida presentó una banda a 1.250 cm-1, que no se detectó en P. caerulea. En esta última la relación de áreas CO/CH del extracto acuoso fue de 3,87; mientras que para P. foetida fue de 1,58; en el extracto metanólico la relación de áreas CO/CH resultó 17,09 para P. caerulea y 15,40 para P. foetida. Estos datos espectrales aportan herramientas que pueden facilitar la caracterización de ambas especies durante el control de calidad de las drogas crudas y de los medicamentos herbarios que las contengan en su formulación. (AU)


Assuntos
Humanos , Plantas Medicinais , Extratos Vegetais , Passifloraceae , Argentina , Cromatografia , Medicina Tradicional
4.
Immunopharmacol Immunotoxicol ; 30(3): 489-501, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18668394

RESUMO

Larrea divaricata is a plant widely used in folk medicine in Argentina. This work aimed to study the mechanisms of decoction activity on the release of oxygen reactive species. Decoction increased the binding of zymosan-FITC and superoxide production. Cadmium decreased the superoxide production as well as malonate and barbital. Decoction decreased the release of hydrogen peroxide. Decoction increased the reduction of MTT but not when malonate and barbital were included. Together, decoction increased the expression of dectin-1 leading to increased superoxide production. It is possible that decoction increases the activity of peroxidase, and decreases the Cu, Zn-superoxide dismutase.


Assuntos
Peróxido de Hidrogênio/metabolismo , Larrea , Macrófagos Peritoneais/efeitos dos fármacos , Extratos Vegetais/farmacologia , Receptores de Complemento/efeitos dos fármacos , Superóxidos/metabolismo , Animais , Barbital/farmacologia , Cloreto de Cádmio/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Feminino , Larrea/química , Lectinas Tipo C , Macrófagos Peritoneais/metabolismo , Masculino , Malonatos/farmacologia , Proteínas de Membrana/metabolismo , Camundongos , Proteínas do Tecido Nervoso/metabolismo , Componentes Aéreos da Planta , Receptores de Complemento/metabolismo , Zimosan/metabolismo
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