Application of mesoporous silica nanoparticles as drug delivery carriers for chemotherapeutic agents.

Recently, remarkable efforts have focused on research towards enhancing and delivering efficacious and advanced therapeutic agents. Even though this involves significant challenges, innovative techniques and materials have been explored to overcome these. The advantageous properties of mesoporous silica nanoparticles (MSNs), such as unique morphologies and geometries, makes then favorable for use for various drug delivery targeting purposes, particularly in cancer therapy. As we discuss here, MSNs have been utilized over the past few decades to improve the efficiency of anticancer drugs by enhancing their solubility to render them suitable for application, reducing adverse effects, and improving their anticancer cytotoxic efficiency.

Improved corneal bioavailability of ofloxacin: biodegradable microsphere-loaded ion-activated in situ gel delivery system.

The aim of the study was to improve corneal penetration and bioavailability of ofloxacin (OFX) eye preparations. OFX was incorporated in poly (lactide-co-glycolide) as biodegradable microspheres using oil in oil emulsion solvent evaporation technique. The prepared OFX microspheres were then incorporated in Gelrite(®) in situ gel preparation. In addition, OFX Gelrite-based in situ gel formulations were prepared. OFX formulations were characterized for gelling capacity, viscosity, and rheological properties. Release studies for OFX microspheres, OFX in situ gel, and OFX-loaded microspheres in situ gel formulations were carried out to investigate release characteristics of the drug. The prepared OFX formulations were then investigated in vivo compared with commercially available OFX eyedrops. Results showed that the optimum Gelrite concentration was at 0.4%-0.7% w/v; the prepared formulations were viscous liquid transformed into a pourable gel immediately after the addition of simulated tear fluid with a gelling factor of 27-35. Incorporation of OFX-loaded microspheres in Gelrite solution (0.4% w/v) significantly altered the release profiles of OFX-loaded microspheres in situ gel formula compared with the corresponding OFX gels and OFX microspheres. In vivo results in rabbits showed that OFX-loaded microspheres in situ gel formula improved the relative bioavailability by 11.7-fold compared with the commercially available OFX eyedrops. In addition, the longer duration of action of OFX-loaded microspheres in situ gel formula preparations is thought to avoid frequent instillations, which improves patient tolerability and compliance.