Preparation and Characterization of TPGS-Colloidal Silica Microparticles for Enhancement of Solubility and Oral Bioavailability of Lercanidipine Hydrochloride

In this study, colloidal silica microparticles containing solubilizing excipient were prepared using the spray-drying process to enhance dissolution and oral absorption of lercanidipine hydrochloride. Several measurements including scanning electron microscopy, powder X-ray diffraction, particle size determination, in vitro dissolution, and pharmacokinetic study were conducted in rats. Among the tested solubilizing excipients, d-α-tocopheryl polyethylene glycol 1000 succinate (TPGS) dramatically enhanced the solubility of lercanidipine hydrochloride through micelle solubilization. In addition, TPGS-colloidal silica microparticles at the ratio of 1:10:10 (drug:TPGS:colloidal silica) showed rapid dissolution rate in all dissolution media and displayed higher area under the curve and maximum plasma concentration values compared with raw lercanidipine hydrochloride. Therefore, amorphous TPGS-colloidal silica microparticles fabricated using the spray-drying process have great potential in the clinical application of lercanidipine hydrochloride.