The Mineralization Of Esterified Agarose-based Scaffold Material And Its Application On Femur Repair

Bone defect seriously affects people's life.The polymeric materials for bone defect repair have advantage of good processing performance.However,common synthetic polymer such as polylactic acid,polyester materials brings to patients with potential danger as the acidic degradation products,and the natural polymer for bone regeneration often has insufficient mechanical strength.Seeking new bone repair materials is becoming a research hotspot.The previous studies of the esterified agarose(AGA)in our lab indicated that it had biocompatibility,good processing performance,the degradation without an overly acidic environment.Its bio-inert can provide long-term security for orthopedic implants.Meanwhile,it possesses higher mechanical properties compared with natural materials.Thus,this paper would find out the feasibility of esterified agarose as a bone repair material.1.Esterified agarose fibrous membranes were fabricated by electrospun,and mineralization of the fibrous membranein vitro was further explored.The esterified agarose membrane was mineralized in the normal concentration simulated body fluid(SBF)for 15 d and 30 d,respectively.The XRD result showed there are characteristic peak of hydroxyapatite after 15 d mineralization.The TGA showed that a high amount of hydroxyapatite mineralized in the membrane.The presence of hydroxyapatite can be observed by scanning electron microscopy and X-ray energy spectrum.2 Esterified agarose fibrous membranes containing different weight percentages of?-tricalcium phosphate(?-TCP)were successfully developed through electrospinning.?-TCP increases the diameter of the fiber,and improves the hydrophilicity and the mechanical strength of.The AGA based fibrous membranes had a good adhesion to BMSCs and BMSCs proliferated on the fibrous membrane well.It was found that more BMSCs were differentiated to osteoblast-like cells on the ?-TCP containing fibrous membranes compared with the single AGA one,and more alkaline phosphatase(ALP)and mineralized matrix could be detected when BMSCs were cultured on the ?-TCP containing fibrous membranes.The fibrous membranes wereimplanted into SD rats for biocompatibility test.Histological analysis results showed that there were less inflammatory responses.3 A three-dimensional porous scaffold was prepared with AGA by particle leaching process.The rabbit femoral defect repair experiment showed that the esterified agarose scaffold significantly improved the process of bone repair compared with blank control.Compared with PDLLA group,there was no significant difference in bone repair,but it was found that esterified agarose had a slower degradation rate without acidic degradation products.These result showed that AGA had a good biocompatibility and could provide a good mineralized environment in vitro.AGA composited with bio-active particles can through different processing methods,and the resulting scaffold could promote BMSCs proliferation and differentiation to osteogenesis.All of experimental results suggested that the AGA based materials had the great potential to application in bone repair.