RESUMEN
The object of this study was to prepare rosiglitazone maleate (RM) sustained-release floating microspheres and investigate their pharmacokinetics. RM microspheres were prepared with ethyl cellulose (EC) and octadecyl alcohol as the carrier materials by an emulsion-solvent diffusion method, and the properties of morphology in vitro floating capability, drug loading (DL), entrapment efficiency (EE), in vitro release and in vivo pharmacokinetics were investigated. The prepared microspheres had a completely spherical shape. The percentage of microspheres floating after 12 h was (91.45 +/- 1.62)%, and the DL and EE were (9.31 +/- 0.31)% and (89.55 +/- 1.65)% respectively. Pharmacokinetic studies demonstrated that the RM floating microspheres were superior to commercial tablets in terms of the decrease in peak plasma concentration and maintenance of RM concentration in plasma. The area under the curve of plasma concentration-time (AUC) of the floating microspheres was equivalent to that of reference tablets. The results showed that floating microspheres are a feasible approach for the sustained-release preparation of drugs which have limited absorption sites in the upper small intestine.
Asunto(s)
Hipoglucemiantes/administración & dosificación , Hipoglucemiantes/química , Tiazolidinedionas/administración & dosificación , Tiazolidinedionas/química , Adulto , Área Bajo la Curva , Disponibilidad Biológica , Química Farmacéutica , Cromatografía Líquida de Alta Presión , Preparaciones de Acción Retardada , Composición de Medicamentos , Vaciamiento Gástrico , Semivida , Humanos , Hipoglucemiantes/farmacocinética , Absorción Intestinal , Masculino , Microscopía Electrónica de Rastreo , Microesferas , Rosiglitazona , Tiazolidinedionas/farmacocinética , Adulto JovenRESUMEN
In this study, digoxin (DG)-loaded solid lipid nanoparticles (DG-SLNs) were successfully prepared by an ultrasonic and high pressure homogenization method. The particle size and distribution, drug loading capacity, drug entrapment efficiency (EE %), zeta potential, and long-term physical stability of the SLNs were characterized in detail. A pharmacokinetic study was conducted in rabbits after oral administration of 0.25 mg DG in different SLNs and it was found that the relative bioavailability of DG in the SLNs was significantly increased compared with that of a DG solution. The addition of CMC-Na in SLNs also markedly increased the oral absorption of DG. These results indicate that DG absorption is enhanced significantly by employing SLN formulations and SLNs are a potential as an oral delivery carrier for poorly water soluble drugs.
Asunto(s)
Cardiotónicos/administración & dosificación , Cardiotónicos/farmacocinética , Digoxina/administración & dosificación , Digoxina/farmacocinética , Animales , Disponibilidad Biológica , Cardiotónicos/química , Química Farmacéutica , Cromatografía Líquida de Alta Presión , Digoxina/química , Composición de Medicamentos , Estabilidad de Medicamentos , Almacenaje de Medicamentos , Electroquímica , Lípidos , Nanopartículas , Tamaño de la Partícula , Conejos , SolucionesRESUMEN
In this study, solid lipid nanoparticles (SLNs) were successfully prepared by an ultrasonic and high-pressure homogenization method to improve the oral bioavailability of the poorly water-soluble drug cryptotanshinone (CTS). The particle size and distribution, drug loading capacity, drug entrapment efficiency, zeta potential, and long-term physical stability of the SLNs were characterized in detail. A pharmacokinetic study was conducted in rats after oral administration of CTS in different SLNs, and it was found that the relative bioavailability of CTS in the SLNs was significantly increased compared with that of a CTS-suspension. The incorporation of CTS in SLNs also markedly changes the metabolism behavior of CTS to tanshinone IIA. These results indicate that CTS absorption is enhanced significantly by employing SLN formulations, and SLNs represent a powerful approach for improving the oral absorption of poorly soluble drugs.
