Preparation Of Organic-inorganic Hybrid Bone Tissue Engineering Materials By Thiol-alkene Click Chemistry

In traditional tissue engineering applications,a key principle is to develop scaffold materials that can match the mechanical properties of natural tissues,and scaffolds can stimulate stem cell differentiation for tissue regeneration.Bone is a complex composed of hard mineral nanoparticles(hydroxyapatite,HAP)and organic fiber collagen,and HAP is regularly and directionally arranged on the organic fiber collagen.Because of its complex nano-structure,it can form this kind of high-strength and high-toughness structure.Based on the exploration of bone structure,more research tends to simulate the structural characteristics of organic/inorganic hybridization in bone,so as to prepare biomaterials with high strength and toughness.Inspired by the toughening mechanism in nature,we have prepared polyhedral oligomeric silsesquioxane(POSS)-based organic-inorganic hybrid materials.The mechanical properties,biological activities,histocompatibility and promotion of bone repair of the hybrid materials have been systematically studied,providing a new idea for the preparation of high-toughness bone tissue engineering materials.The main contents are as follows:1.POSS-based organic/inorganic hybrid materials were prepared by click chemistry.The structure,thermodynamic stability,strength and toughness of the hybrid materials were analyzed by infrared,XRD,TGA,swelling properties,contact angle,scanning electron microscope and mechanical properties tests.The results show that the strength and toughness of POSS-based organic/inorganic hybrid materials can be adjusted by changing the reactive flexible chain in the middle.The compression test proves that the hybrid materials have high strength and toughness,which meet the requirements of mechanical properties in bone tissue engineering materials.2.POSS-based organic/inorganic hybrid materials exhibit excellent biological activity by forming plate-like hydroxyapatite crystals in simulated body fluid(SBF),and exhibit good cell adhesion and cell compatibility.POSS-based organic/inorganic hybrid materials can also be used to guide differentiation and mineralization of adipose tissue-derived mesenchymal stem cells.3.We evaluated the histocompatibility of the hybrid materials by establishing a mouse subcutaneous implantation model and sampling at different times after operation.In addition,we established a rabbit femoral condyle defect model to evaluate the bone histocompatibility and their ability to promote bone defect repair of two hybrid materials(OEG1-POSS,OEG2-POSS).The results show that POSS-based organic/inorganic hybrid materials have good histocompatibility.And the ability to promote bone repair.Therefore,POSS-based organic/inorganic hybrid materials can be applied to bone tissue engineering as a class of high-performance biomaterials.