| At present, human bone tissue repairing materials are divided into three types: self body bone transplant, variant body same bone transplant, synthetic materials. Self body transplant would cause new hurt on supply area; variant body transplant would cause immunogenicity and disease transmission. So human hopes to develop ideal artificial alternative bone to repair defect bone. Polymer-based inorganic composite drug-carrying bone repairing nanometer materials not only have good surface effect and strong interface bonding performance of nanometer materials, and have go od rigidity, dimensional stability, thermal stability performance of inorganic, but also have good toughness, bonding property, easy workability, degradability performance of polymer. Presently the target of material researchers and clinical doctor s is that bone repairing materials have good repairing performance and good drug carrying performance to release drug slowly and locally.This paper prepares polymer-based inorganic drug-carrying bone repairing nanometer materials n-HA/PA/CS/EM composite materials by nano-Hydroxyapatite(n-HA), Polyamide(PA) like collagen structure and human bone, Chitosan(CS) with good degradation and good bone creation, antibiotics drug erythromycin(EM). This paper tests physical and chemical properties, biological evaluation and biocompatibility on the composite materials, and shows that the materials have good bioactivity of n-HA, good strength, toughness, easy workability of PA, good biocompatibility, degradability of CS. This paper also study drug release performance. The study and the results are as followings:1. Porous composite n-HA/PA/CS are prepared in this experiment by solution blending method, CS content and n-HA content on mechanical performance effect are studied, and IR, XRD, SEM are used to characterize porous composite performances. Study suggests that when the ratio of CS is from 10w% to 30w%, water absorption rate is 7~13w%, the composite press strength is 12~19 MPa to be fit for body bone mechamical performance, these data is fit for artificial bone requirement. SBF soaking shows that the composite is fit for creating in body. SEM study suggests that 100~150μm pore is benefit for osteoid tissue and blood vessel creating, and is conductive to transmit nutrients create mineralized bone. TG analysis shows that the composite has good thermal stabi lity. Comprehensive analysis of FTIR and XRD shows that n-HA/PA/CS are easy to be blended uniformly to format stable chemical interface because of n-HA good surface activity and PA/CS polarity.2. Several biological evaluation experiment results by GB/T 16886.1-2001 on composite n-HA/PA/CS shows that the composite have not acute poisoning; cells poison in vitro is 0,1 scale; skin reaction type is microscopic level; late onset allergic reaction is 0 level; and no Hemolysis phenomenon happens. The composite have met the international requirement and are qualified biological materials.3. Drug-delivery performance is tested on n-HA/PA/CS/EM composite by turn basket method and semipermeable membrane method, using SBF as release medium. The experiment shows that time of maximum concentration by turning basket is 24 hours, and time for maximum concentration by semipermeable membrane is 48 hours. When CS content is increased from 0 to 30w%, the composite is released from 41.6w% to 82.4w%, this shows that CS is benefit for medicine release, EM release quantity increases with CS content increasing. EM can release for 7 days continuously, it is shown that EM can not cause chemical composite and structure changing by FTIR and XRD tests. |
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