Hidrogéis Nanocompósitos Termossensíveis aplicados no crescimento de Células–tronco Mesenquimais e Condrócitos para a engenharia tecidual

Abstract

Injectable biomaterials have gained prominence in tissue engineering since they present a minimal invasive option for therapeutic delivery. However, longer gelation time, instability of physicochemical properties, cytotoxicity and scarce in vitro and in vivo studies limited these biomaterials for clinical practice. In this study, it was proposed the in situ synthesis of nanocomposites based on the thermosensitive polymer poly(N-vinylcaprolactam) (PNVCL) as potential injectable biomaterials for cartilage tissue engineering due to their biocompatibility and ability to gel at physiological temperature. The combination of PNVCL with poly(vinyl acetate) and modified mesoporous silica nanofibers (SiO2-MPS) enabled obtaining thermosensitive nanocomposites with a diffuse phase transition below the room temperature, suitable for application as injectable biomaterials. In addition, the materials exhibited higher rheological properties in the presence of SiO2-MPS and PVAc, and dependent on the concentration of the hydrogels and the temperature, which resulted in an interconnected structure formed between the polymer chains covalently bonded to SiO2-MPS. The evaluation of the biological activity of the materials demonstrated that they were biocompatible with mesenchymal stem cells (MSCs) and chondrocytes (CDs). Additionally, hydrogels of PNVCL and PNVCL with 1 % of SiO2-MPS maintained the chondrocytes phenotype, induced chondrogenic differentiation of MSCs and secreted neocartilage components. Therefore, these studies demonstrate the distinct properties that nanocomposites based on thermosensitive polymers can perform, expanding their perspectives of application, especially as injectable biomaterials in tissue engineering.