Desenvolvimento de modelo de microesfera de poli(ácido láctico-co-glicólico) como arcabouço para esferoide condrogênico: aplicações na regeneração da cartilagem articular

Abstract

Introduction: Articular cartilage is a highly organized tissue that facilitates smooth movements in diarthrodial joints. Notable for its unique ability to support weight and reduce friction, hyaline cartilage is devoid of vascular, neural, and lymphatic networks, as well as local progenitor cells. These characteristics make it particularly challenging to restore function and integrity after traumatic or degenerative injuries. Objective: To develop a new therapeutic alternative with poly(lactic-co-glycolic acid) (PLGA) copolymer microspheres for chondrocyte culture, based on an in vitro model aiming at future clinical applications in osteoarthritis (OA), and to compare two PLGA protocols by simple emulsion and solvent evaporation, regarding the production of scaffolds for cell culture. Methods: Microspheres were synthesized using the simple emulsion method with solvent evaporation, comparing two protocols: (1) using 500 mg of PLGA 80:20 dissolved in 12 mL of CHCl₃, mixed with a PVA solution at 0 .25% and homogenized at 10,000 rpm. The emulsion was sonicated for 10 minutes, stirred for 24 hours, centrifuged, washed, frozen at -20°C, and freeze-dried at - 100°C, (2) microspheres produced by dissolving PLGA 80:20 in CHCL3. 1% PVA was added to this solution, with a stirring speed of 500 rpm on a magnetic stirrer (DOX-AGIT) for 18 hours. The microspheres were washed in sterile deionized water and lyophilized for 24h at - 100°C. The characterization of the microspheres was evaluated with Scanning Electron Microscopy (SEM) with analysis of the diameter of the spheroids. Results: after evaluating the two protocols used, protocol 2 was the one that produced microspheres with the best characteristics for cell culture, with diameters ranging from 2.6 to 398.3 μms, the majority being between 100 and 300 μms. Conclusion: The results of this study demonstrated that Protocol 2 was superior in the production of microspheres for cell culture. Given the physiological difficulties associated with this tissue, the analyzed protocol may represent a promising alternative for future clinical applications