RESUMO
This work aimed at improving the solubility of curcumin by the preparation of spray-dried ternary solid dispersions containing Gelucire®50/13-Aerosil® and quantifying the resulting in vivo oral bioavailability and anti-inflammatory activity. The solid dispersion containing 40% of curcumin was characterised by calorimetry, infrared spectroscopy and X-ray powder diffraction. The solubility and dissolution rate of curcumin in aqueous HCl or phosphate buffer improved up to 3600- and 7.3-fold, respectively. Accelerated stability test demonstrated that the solid dispersion was stable for 9 months. The pharmacokinetic study showed a 5.5-fold increase in curcumin in rat blood plasma when compared to unprocessed curcumin. The solid dispersion also provided enhanced anti-inflammatory activity in rat paw oedema. Finally, the solid dispersion proposed here is a promising way to enhance curcumin bioavailability at an industrial pharmaceutical perspective, since its preparation applies the spray drying, which is an easy to scale up technique. The findings herein stimulate further in vivo evaluations and clinical tests as a cancer and Alzheimer chemoprevention agent.
Assuntos
Anti-Inflamatórios/química , Anti-Inflamatórios/farmacocinética , Curcumina/química , Curcumina/farmacocinética , Estabilidade de Medicamentos , Animais , Anti-Inflamatórios/farmacologia , Disponibilidade Biológica , Química Farmacêutica/métodos , Curcumina/farmacologia , Gorduras/química , Gorduras/farmacocinética , Gorduras/farmacologia , Masculino , Óleos/química , Óleos/farmacocinética , Óleos/farmacologia , Ratos , Ratos Wistar , Dióxido de Silício/química , Dióxido de Silício/farmacocinética , Dióxido de Silício/farmacologia , Solubilidade , Tecnologia Farmacêutica/métodos , Difração de Raios X/métodosRESUMO
WHAT IS KNOWN AND OBJECTIVE: Cannabis withdrawal in heavy users is commonly followed by increased anxiety, insomnia, loss of appetite, migraine, irritability, restlessness and other physical and psychological signs. Tolerance to cannabis and cannabis withdrawal symptoms are believed to be the result of the desensitization of CB1 receptors by THC. CASE SUMMARY: This report describes the case of a 19-year-old woman with cannabis withdrawal syndrome treated with cannabidiol (CBD) for 10 days. Daily symptom assessments demonstrated the absence of significant withdrawal, anxiety and dissociative symptoms during the treatment. WHAT IS NEW AND CONCLUSION: CBD can be effective for the treatment of cannabis withdrawal syndrome.
Assuntos
Canabidiol/uso terapêutico , Cannabis/efeitos adversos , Síndrome de Abstinência a Substâncias/tratamento farmacológico , Adulto , Feminino , Humanos , Adulto JovemRESUMO
An original, simple, specific, and rapid high-performance liquid chromatography assay for the determination of clofazimine in human plasma is presented. The procedure consists of extracting the drug and the internal standard (medazepam) from 0.5 mL plasma with dichloromethane/diisopropyl ether (1:1, v/v) at pH 3.0, after precipitating the proteins with methanol. The drugs were then quantitated on a reversed-phase C8 using a mobile phase consisting of a mixture of methanol/0.25 N sodium acetate buffer at pH 3.0 (74:26, v/v). The flow-rate and wavelength were set at 1 mL/min and 286 nm, respectively. The precision, linearity, and limit of quantitation of the method were within acceptable limits. The method was considered adequate and could be applied in studies involving blood level monitoring and pharmacokinetics in leprosy patients.
Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Clofazimina/farmacocinética , Monitoramento de Medicamentos/métodos , Hansenostáticos/farmacocinética , Hanseníase/metabolismo , Clofazimina/uso terapêutico , Feminino , Humanos , Hansenostáticos/uso terapêutico , Hanseníase/tratamento farmacológico , Masculino , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
A sensitive and automated method is described for determination of rifampicin in plasma samples for therapeutic drug monitoring by in-tube solid-phase microextraction coupled with liquid chromatography (in-tube SPME/LC). Important factors in the optimization of in-tube SPME are discussed, such as coating type, sample pH, sample draw/eject volume, number of draw/eject cycles, and draw/eject flow rate. Analyte pre-concentrated in the polyethylene glycol phase was directly transferred to the liquid chromatographic column by percolation of the mobile phase, without carryover. The method was linear over the 0.1-100 µg/mL range, with a linear coefficient value (r(2)) of 0.998. The inter-assay precision presented coefficient of variation ≤ 1.7%. The effectiveness and practicability of the proposed method are proven by analysis of plasma samples from ageing patients undergoing therapy with rifampicin.