Preparation And Properties Of An Organosilicone Hybrid Biomaterial And Gelatin Composites

Biomaterials with biological activity have always been an important research in the field of bone regeneration,but many biological materials have low biological activity,poor certain mechanical properties and biocompatibility.In this paper,organic-inorganic hybrid materials were the main research objects to explore their preparation methods and compounding with gelatin to prepare bioactive materials.In the first part,oligomer with short organic molecular chains was successfully synthesized with KH550 and KH560.The oligomer was mixed with tetraethylorthosilicate and calcium chloride to prepare organic-inorganic hybrid bioactive material(OI-BM)by sol-gel method,and its structure and properties were fully characterized.OI-BM exhibited elastic deformation under compression.The elastic modulus and ultimate stress of OI-BM were respectively 0.4±0.1 GPa and 23.0±4.0 MPa.The elastic modulus and ultimate stress of 45S5-BG were respectively 1.1±0.1 GPa and 32.0±5.0 MPa,which were lower than those of 45S5-BG.The elastic modulus and ultimate stress,while the failure strain and toughness modulus of OI-BM were respectively 4.5 times and 4 times that of 45S5-BG.OI-BM was easy to shape and has certain mechanical properties and excellent machining properties.OI-BM could produce hydroxyapatite in simulated body fluids in just one hour,which has excellent biological activity.CCK-8 analysis further proved the cytocommpatibility of OI-BM.Therefore,this organic-inorganic hybrid bioactive material has potential application value in bone transplantation.In the second part of the work,gelatin and OI-BM composites were used as raw materials,and a gelatin/OI-BM composite fiber mat capable of local drug delivery was prepared by electrospinning,metronidazole was used as a local drug delivery.The study found that the gelatin/OI-BM composite fiber loaded with metronidazole could trigger the formation of hydroxyapatite on the surface of the fiber mat,thereby exhibiting obvious biological activity,while the gelatin/OI-BM composite fiber mat without metronidazole loading The ability to initiate the formation of hydroxyapatite on the surface was low,so the biological activity was low.The mechanism may be the formation of Ca2+ channels caused by the release of metronidazole and the acidic environment brought about by the release of metronidazole,which promoted the release of Ca2+by OI-BM,and made the gelatin/OI-BM composite fibers form hydroxyapatite,ability was significantly enhanced.This point of view was verified by SEM,XRD,ICP,changes in pH and the release of metronidazole.After OI-BM was added,the mechanical properties of gelatin fibers were significantly enhanced,elongation at break increased by 4%,modulus of elasticity increased by 48.6%,and tensile strength increased by 2.5 times.On the basis of not changing the morphology of the gelatin fiber,the addition of organic-inorganic hybrid biological materials and metronidazole enabled the gelatin fiber to achieve the purpose of local drug delivery while having biological activity and a certain strength.The third part adopted a high-temperature calcination method,and the OI-BM prepared in the first part was calcined to obtain the porous bioactive material(PBM).Because PBM has a continuous interpenetrating channel structure,it was used to load ibuprofen.The Ibuprofen-loaded PBM was compounded with gelatin,and a gelatin bioactive scaffold with sustainable drug release was prepared by freeze-drying.The content of ibupro fen loaded in PBM could reach 25.73%by thermogravimetric test.The release effect of ibuprofen in PBM and PBM/Gelatin was tested by UV spectrophotometer,and it was found that the encapsulation effect of gelatin enabled the PBM/Gelatin composite scaffold to achieve drug delivery.Slowly and continuously release.After 30%IBU-PBM was added,the elastic modulus and yield stress of the composite scaffold were increased by 266%and 147%compared with the gelatin scaffold.Compared with the pure gelatin scaffold,the PBM/Gelatin composite scaffold has higher mechanical properties,and the scaffold has certain the biological activity.This PBM/Gelatin composite scaffold has potential application value in the field of bone graft biomaterials.