Cross-Linked Castor Oil-Based Hybrid Microparticles as Drug Delivery Systems

Vegetable oil-based microparticles were elaborated using environmentally friendly chemistry for pharmaceutical applications such as drug delivery systems. Castor oil (CO) was cross-linked by sol–gel chemistry to obtain a hybrid material offering original properties. CO functionalization was successfully achieved in the bulk with 3-isocyanatopropyltriethoxysilane (IPTES), then a simple and robust o/w emulsion process allowed both shaping functionalized oil into microparticles and favoring oil cross-linking. Several parameters were studied such as the stirring mode or the gelling agent for controlling microparticle characteristics. Spherical hybrid microparticles with a monodispersed size (around 300 μm) and a hybrid composition (13% w/w of mineral part) were characterized by size measurement, electronic microscopy, energy-dispersive X-ray spectroscopy, and thermal analysis. The effectiveness of the microparticles as potential drug delivery systems using ibuprofen as model molecule was demonstrated with a l...