Dexamethasone-loaded poly(ɛ-caprolactone)/silica nanoparticles composites prepared by supercritical CO2 foaming/mixing and deposition

• Published in: International journal of pharmaceutics Vol. 456; no. 2; pp. 269 - 281
• Main Authors: de Matos, M.B.C., Piedade, A.P., Alvarez-Lorenzo, C., Concheiro, A., Braga, M.E.M., de Sousa, H.C.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 18-11-2013
• Subjects: carbon dioxide; Carbon Dioxide - chemistry; Chromatography, Supercritical Fluid - methods; composite materials; Composites; dexamethasone; Dexamethasone - chemical synthesis; foaming; Mezoporous silica nanoparticles; mixing; nanoparticles; Nanoparticles - chemistry; Poly(ɛ-caprolactone); Polyesters - chemical synthesis; Silicon Dioxide - chemical synthesis; solvents; Supercritical CO2 foaming/mixing; Supercritical CO2 impregnation/deposition; X-Ray Diffraction; Supercritical CO2 foaming/mixing; Supercritical CO2 impregnation/deposition; Composites; Poly(ɛ-caprolactone); Mezoporous silica nanoparticles; Supercritical CO impregnation/deposition; Supercritical CO foaming/mixing
• ISSN: 0378-5173; 1873-3476
• DOI: 10.1016/j.ijpharm.2013.08.042

A supercritical carbon dioxide (scCO2)-assisted foaming/mixing method (SFM) was implemented for preparing dexamethasone (DXMT)-loaded poly(ɛ-caprolactone)/silica nanoparticles (PCL/SNPs) composite materials suitable for bone regeneration. The composites were prepared from PCL and mesoporous SNPs (MCM-41/SBA-15) by means of scCO2-assisted SFM at several operational pressures, processing times and depressurization conditions. DXMT was loaded into SNPs (applying a scCO2 solvent impregnation/deposition method – SSID) and into PCL/SNPs composites (using the SFM method). The effects of the employed operational and compositional variables on the physicochemical and morphological features as well as in the in vitro release profiles of DXMT were analyzed in detail. This work demonstrates that the above-referred scCO2-based methods can be very useful for the preparation of DXMT-loaded PCL/SNPs composites with tunable physicochemical, thermomechanical, morphological and drug release properties and suitable for hard-tissue regeneration applications.