POLYCAPROLACTONE MICROPARTICLES IN CHITOSAN/PLURONIC THERMOGEL FOR DEXAMETHASONE DELIVERY

Abstract

The use of local intra-articular injection therapy for the treatment of osteoarthritis has experienced an increase in recent decades. With this treatment, frequent injections are necessary to obtain an adequate anti-inflammatory effect, which implies greater inconveniences for the patients. An alternative could be use injectable controlled release systems that allow to reduce the frequency of application. The aim of this research is to develop a system based on dexamethasone-loaded polycaprolactone particles dispersed in a thermosensitive chitosan/Pluronic® F-127 hydrogel. The microparticles were obtained by the double emulsion / solvent evaporation technique. The hydrogel is prepared from a physical mixture of chitosan and Pluronic® F127. The microparticle / hydrogel system was prepared by dispersing 50 mg of particles in 2 mL of the liquid hydrogel. The samples were characterized by Fourier transform infrared spectroscopy and scanning electron microscopy. The cytocompatibility of the samples was evaluated using the C-28 cell line of human chondrocytes by the 3- (4,5-dimethylthiazol-2-yl) -5- (3-carboxymethoxyphenyl) -2- (4-sulfophenyl) -2H-tetrazolium (MTS) assay and a study of dexamethasone release in phosphate buffered saline solution (PBS) was carried out for 7 days. The particles have a defined spherical shape and a size between 4-14 µm. The characterization by Fourier transform infrared spectroscopy showed that there are no chemical interactions between chitosan and Pluronic® F127 in the hydrogel. All the analyzed samples were cytocompatible with the C-28 cell line. The release study showed that the system has greater control over dexamethasone release. The system proves to be a promising option as an intra-articular administration system in the pharmacological treatment of osteoarthritis.