Oxidized Mesoporous Silicon Microparticles for Improved Oral Delivery of Poorly Soluble Drugs. Molecular pharmaceutics [Mol Pharm] Journal article

Surface functionalized mesoporous silicon (pSi) microparticles are reported as a solid dispersion carrier for improving dissolution and enhancing the orally administered pharmacokinetics (fasted rat model) of indomethacin (IMC) - employed as a model poorly soluble BCS type II drug. IMC was loaded via immersion/solvent evaporation onto the thermally oxidized pSi particles, which provide a stable hydrophilic matrix with a nano-porous structure. The solid state properties of IMC loaded pSi were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray powder diffraction (XRD), differential scanning calorimetry (DSC) and thermogravametric analysis (TGA). IMC molecules are encapsulated in a non-crystalline state due to geometric confinement in the nano-pores; stability of the non-crystalline state has been demonstrated for several months under accelerated storage conditions. The pSi carrier facilitates accelerated immediate release of IMC and enhanced oral delivery performance in comparison with crystalline indomethacin and Indocid(R) i.e. a 4-times reduction on Tmax, a 200% increase on Cmax and a significant increase in bioavailability. The in vitro-in vivo correlation (IVVC) is discussed based on non-compartment model and gives insight into the delivery mechanism for the pSi carrier.

Molecular pharmaceutics [Mol Pharm]