RESUMEN
Solid lipid nanoparticles (SLNs) and nanosuspensions (NSs) have shown great promise for improving bioavailability of poorly water-soluble drugs. This study was aimed to develop SLNs and NS of Saquinavir (SQ) for improvement in bioavailability. These formulations were characterized and their pharmacokinetics and biodistribution in mice were evaluated. Saquinavir-loaded SLNs (SQSLNs) showed particle size 215 ± 9 nm and entrapment efficiency 79.24 ± 1.53%, while solid-state studies (differential scanning calorimetry and X-ray diffraction) indicated entrapment of the drug in SLNs. Saquinavir NS (SNS) showed particle size 344 ± 16 nm with fourfold increase in saturation solubility and its solid-state studies showed reduction in crystallinity. Pharmacokinetics and biodistribution studies of orally administered SQSLN and SNS in mice exhibited higher plasma level concentration compared to saquinavir microsuspension (SMS). The relative bioavailabilities for SNS and SQSLN were 37.39% and 66.53%, respectively, compared to 18.87% bioavailability obtained after administration of SMS, indicating suitability of nanoparticulate formulations for improving bioavailability.
Asunto(s)
Portadores de Fármacos/química , Inhibidores de la Proteasa del VIH/administración & dosificación , Inhibidores de la Proteasa del VIH/farmacocinética , Lípidos/química , Nanopartículas/química , Saquinavir/administración & dosificación , Saquinavir/farmacocinética , Animales , Rastreo Diferencial de Calorimetría , Femenino , Infecciones por VIH/tratamiento farmacológico , Masculino , Ratones , Nanopartículas/ultraestructura , Tamaño de la Partícula , Solubilidad , Difracción de Rayos XRESUMEN
Stereoselective synthesis of an E-hydroxystilbene has been carried out using the McMurry reaction. Synthesis of a monoiodinated hydroxystilbene has been carried out by a McMurry cross-coupling reaction. For the purpose of biological evaluation, the facile electrophilic substitution route has been attempted to radioiodinate it with (125)I. The HPLC pattern of the radioiodinated hydroxystilbene, which could be obtained in >90% radiochemical purity, was found to be identical to that of its non-radioactive analog that has been independently prepared using the McMurry cross-coupling route. In vitro cell uptake studies were carried out in breast cancer cells MCF7, overexpressing estrogen receptors. In vivo biodistribution studies in female Swiss mice show a uterine uptake of 0.85±0.4% ID/g at 3h.p.i. with a uterus to muscle ratio of 2.83. Uptake in the thyroid was insignificant indicating good in vivo stability of the radioiodinated hydroxystilbene.
