Surface functionalization of acrylic based photocrosslinkable resin for 3D printing applications

The limited number of resins,available for stereolithography applications,is one of the key drivers in research applied to rapid prototyping.In this work an acrylic photocrosslinkable resin based on methyl methacrylate(MMA),butyl methacrylate(BMA)and poly(ethylene glycol)dimethacrylate(PEGDA)was developed with different composition and characterized in terms of mechanical,thermal and biological behaviour.Two different systems have been developed using different amount of reagent.The influence of every components have been evaluated on the final characteristic of the resin in order to optimize the final composition for applications in bone tissue engineering.The crosslinked materials showed good mechanical properties and thermal stabilities and moreover cytotoxicity test confirms good biocompatibility with no cytotoxic effect on cells metabolism.Moreover two different treatments have been proposed,using fetal bovine serum(FBS)and methanol(MeOH),in order to improve cell recognition of the surfaces.Samples threatened with MeOH allow cell adhesion and survival,promoting spreading,elongation and fusion of C2C12 muscle myoblast cells.

In situ sol-gel synthesis of hyaluronan derivatives bio-nanocomposite hydrogels

The main driving idea of the present study was the comparison between two different chemical modifications of hyaluronic acid(HA)followed by the development of nanocomposite hydrogels directly in situ by biomineralization of photocrosslinkable HA polymers through sol-gel synthesis.In this way,it has been possible to overcome some limitations due to classical approaches based on the physical blending of inorganic fillers into polymer matrix.To this aim,methacrylated and maleated HA,synthesized with similar degree of substitution(DS)were compared in terms of mechanical and physico-chemical properties.The success of in situ biomineralization was highlighted by reflect Fourier transform infrared spectroscopy and thermogravimetric analysis.Furthermore,mechanical characterization demonstrated the reinforcing effect of inorganic fillers evidencing a strong correlation with DS.The swelling behavior resulted to be correlated with filler concentration.Finally,the cytotoxicity tests revealed the absence of toxic components and an increase of cell proliferation over culture time was observed,highlighting these bio-nanocomposite hyaluronan derivatives as biocompatible hydrogel with tunable properties.