Preparation And Performance Research Of Porous N-HA/PEEK/CS And N-HA/PEEK/C₈-HPCS Composite Materials

With the rapid development of biotechnology, improvement of people's life and economic and the growth of aging people, people pay attention to the rehabilitation of health and medical more and more. Amony which bone defect caused by accidents, trauma, infections and other causes, etc. is an important issue to be resolved. At present, repairing materials of artificial bone used clinically are as follows: Self body bone transplant, Variant body same bone transplant and synthetic materials. Although Self body bone transplant is not easy to cause rejection, it always results in new damage and neopathy at the don or site. On the other hand, Variant body same bone transplant always leads to immunogenicity disease transmission and so on. Therefore artificial bone substitutes become the research focus as reparing materials for bone plerosis.Polymer-based composite combines the rigidity, dimensional stability, and toughness of inorganic filler, with ductility, adhesion, processing and rudubility of polymer. That composite possess good medicinical properties biocompatibility and biodegradability appropriate replacement, is an ideal reparing material of bone defect. During the treatment of bone defect two or more pathological changes inflammation and infection will appear, traditional medicine injections are adapt. However, it can cause concentration fluctuated phenomenon or side effects of antibiotics. Thus anti-infective agents is incorporated in the bone subsititutes to prepare a new drug porous composite bone repair material.It not only can resist infection but also release sustainablely and effectively, which acts together to treat the bone defect.This paper shows that the polymer-based inorganic bone substitutes n-HA/PEEK/CS/TOB and n-HA/PEEK/CS/C₈-HPCS/TOB composite smaterials are prepared by nano-Hydroxyapatite?n-HA?, Polyether ether ketone?PEEK? like human bone, Chitosan?CS? and O-hydroxypropyl chitosan-N-octyl?C₈-HPCS? with good degradation and great bone creation, antibiotics drug Tobramycin?TOB?. The physical and chemical properties, biological evaluation and biocompatibility of the composite materials are tested, drug release performance is also studied by this paper. The study and the results are as followings:1. Different ratios of composite n-HA/PEEK/CS are prepared in this experiment by microwave solution blending method and their basic properties are explored. Characterized porous composite performances which show different components of the display surface morphology evenly disperses composite are studied by the Scanning electron microscope?SEM?. Simultaneous thermal analysis?TG? shows that its thermal stability is good. X-ray diffraction?XRD? test is showed that the crystalline state of the composite material does not change significantly. Infrared Spectroscopy?FTIR? is showed that the composite material contains only the main characteristic peaks of single component, with no significant shift or a new peak. The composite water absorption and mechanical properties of test results are showed when the water absorption of the composite material are 2²0%, compressive strength will reach 9¹9MPa. The tests show that composite conform the requirements of bone tissue mechanical properties.2. Preparation of porous n-HA/PEEK/CS composite particles are explored by the legal hole, measured porosity and its other basic performance. The results show that the total porosity of the porous n-HA/PEEK/CS composite is 37 ⁷5%. Combined with FTIR, XRD analysis, it easier to mix n-HA, PEEK and CS, the high surface activity of n-HA and the polarity of them, which may also be formed between three good chemical inter face. SEM shows that the hole diameter of the porous in composites between 150⁵00?m, so it is filled the biology requirements of the hole that it is beneficial to cell, tissue ingrowth.3. Several biological evaluation experiment results by GB/T 16886.1-2001 on porous n-HA/PEEK/CS composite show that the composite ha s no acute poisoning and Hemolysis phenomenon to happen. Simulated body fluid?SBF? experiments are showed that after 30 h immersion system p H is varied between 7.40⁷.50, suggesting that bone tissue repair material is suitable for the growth of the human body in a similar environment. Thus porous n-HA/PEEK/CS composite bone substitutes have good biological properties and conform the basic requirements of biomedical materials.4. O-hydroxypropyl chitosan-octyl?C₈-HPCS? is modified by Microwave and Phase Transfer Catalysis, then the porous n-HA/PEEK/C₈-HPCS is prepared and its performance is detected. The results show that the critical micelle concentration of C₈-HPCS is 0.015g/L, the surface tension is 58.5m N /m, the HLB is 13.44. XRD is showed C₈-HPCS amorphous structure chitosan derivatives; TG is showed good thermal stability of C 8-HPCS; FTIR and nuclear magnetic resonance?NMR? structural analysis is showed that CS is modified to C₈-HPCS structure which is consistent with anticipation.The characteristic peaks of porous composites is unchanged, which each component material characteristic peak shift less and the structure.5. The antibiotic Tobramycin?TOB? loading in n-HA/PEEK/CS and n-HA/PEEK/C₈-HPCS composites are prepared via the blending method. Drugs physical and chemical properties are explored, drug-delivery performance is tested on composites by semipermeable membrane method, using SBF as release medium. The experimental results show that when the content of composites is increased from 0 to 30%, the release of drugs is increased from 34.60% to 87.50%. Under the same conditions, the release of C 8-HPCS composites from the drug is increased from 34.60% to 94.29%, indicating that the biodegradable material CS and C₈-HPCS added are conducive to dissolution of the drug, and the drug release increasely composites with increasing CS and C 8-HPCS. In comparison, the modified chitosan C₈-HPCS promotes drug to release and k eeps drug releasing sustainably better than CS, and TOB in simulated body fluid release time can be up to 15 days. FTIR and XRD show t hat the chemical composition of composite materials and structures are not changed with the addtion of Tobramycin.