Study On The Biomineralization Of Nanofiber Fabric And Cellulose Nano-whisker To Build Bone Repair Materials

The common phenomenon of human bone tissue defect or dysfunction resulted from the development of industry, transportation, sports and the aging of the population. Therefore, the clinical bone substitute materials have great demand. Autograft and allograft bone repair have larger defects for the repair and treatment of bone tissue. With the development of science and technology, the artificial biomedical materials are widely used for bone repair or replacement in clinical. This study employs two different methods and with natural bone structure as a starting point obtained have good biological and biomechanical properties of bone repair materials. One bionic natural structure material for bone repair is prepared by mineralization of nanofibers. The electro-spun technology is used to prepare yarns with twist and nanofibers along the axis orientation, and the yarns were weaving into multilayer fabrics. After the simulated body fluid mineralization of multilayer fabrics to build fabric enhanced bionic bone materials. The result showed that when the mass ratio of polylactic acid (PLA) and tussah silk fibroin (TSF) is 9:1, we can obtain continuously and fineness of uniform and good mechanical properties yarns by electro-spun technology. The multilayer fabric prepared by the yarns has tensile fracture strength of 417.65 MPa and young’s modulus of 180.36MPa. After mineralizing, the fabric shows a higher compression modulus of 1082.54 MPa and compression stress of 91.97 MPa. Related biological performance study shows that mineralization of composite nanofibers fabric is more advantageous to cell growth, proliferation and functional expression. Another bionic natural bone structure material for bone repair is prepared by mineralization of cellulose nano-whisker. Making use of the electrostatic self-assembly bionic mineralization obtain carboxymethylated cellulose nano-whisker (SCNW)/hydroxyapatite (HAP) composite particles, and combining the silk fibroin to preparation of gradient distribution density and porosity of porous material. The results indicated that carboxymethylated modification on the surface of nano-whisker is realized in the control growth of HAP. The HAP crystal is weak under the regulation of Chitosan (CS) that has smaller grain size (the average size is 30.2nm). The grain size is similar to HAP (10-50nm) in natural bone. The compression performance indicated that the compression strength (142.68MPa) and the compression modulus (2013.27 MPa) of gradient material prepared by SCNWV HAP (1:4) composite particles with SF is comparable to the test values of natural bone. In vitro cell culture results showed that the SCNW/HAP-TSF (1:4) composite material is advantageous to cell adhesion, growth, proliferation, and differentiation and functional expression. In general, the preparation method of these two kinds of material can provide new thought and theoretical basis for the design of bone repair materials.