镁合金AZ31B材料表性与成骨细胞的黏附

背景：镁合金对成骨细胞的生物学行为及早期黏附是否有影响尚不明确。 目的：分析镁合金AZ31B的表性,并评价其对成骨细胞黏附的影响。 方法：采用扫描电镜及能谱分析明确镁合金AZ31B的表面形态及元素组成。以蛋白吸附实验检测镁合金AZ31B与钛合金对蛋白的吸附能力。将镁合金AZ31B与钛合金分别与小鼠前成骨细胞MC3T3-El共培养于24孔板内,观察培养2,6,24 h的细胞黏附情况。 结果与结论：扫描电镜可见镁合金AZ31B表面较为粗糙,有利于细胞在其表面的黏附.能谱分析结果表明镁合金AZ31B的主要元素有镁、铝、锌,其中镁约占96%,铝约占3%,锌约占1%,另有一些其他元素,含量较少。镁合金AZ31B与钛合金的蛋白吸附率差异无显著性意义。培养2 h时,镁合金AZ31B与钛合金上的细胞黏附率差异无显著性意义;培养6,24 h,镁合金AZ31B上的细胞黏附率显著低于钛合金上的细胞黏附率(P < 0.01)。培养于镁合金表面的成骨细胞贴壁展开,形态不规则,大多呈梭形,有较多突起,部分细胞间突起相互连接。表明镁合金AZ31B具有良好的细胞黏附性,适合于成骨细胞的早期黏附。     

氟转化涂层镁合金材料与诱导后人骨髓间充质干细胞的相容性*

背景：氟转化涂层的AZ31B镁合金和β-磷酸三钙涂层的AZ31B镁合金是中科院金属研究所新研制的镁合金,是否具有良好的生物相容性尚不确切。 目的：以诱导的人骨髓间充质细胞作为检测细胞,评价氟转化涂层的AZ31B镁合金和β-磷酸三钙涂层的AZ31B镁合金材料的细胞相容性。 方法：实验分为镁合金AZ31B组,氟转化涂层的AZ31B镁合金组和β-磷酸三钙涂层的AZ31B镁合金组。以诱导的人骨髓间充质细胞作为检测细胞,分别取3种材料浸提液进行体外细胞相容性实验。 结果与结论：氟转化涂层的AZ31B镁合金和β-磷酸三钙涂层的AZ31B镁合金材料细胞毒性分级均为1级,镁合金AZ31B材料细胞毒性分级为2级。提示氟转化涂层的AZ31B镁合金和β-磷酸三钙涂层的AZ31B镁合金材料生物相容性优于未经处理镁合金AZ31B材料。     

重视镁合金支架在胆管癌中的研发应用

胆管癌是胆道外科常见的恶性肿瘤,可发于胆管的任何分支[1].由于肝门区解剖位置和胆管癌的生物学特征,胆管癌早期诊断困难,同时根治性手术切除率低(10％～20％)[2],放化疗敏感性差,远期生存不理想.尤其是当胆管癌出现胆道梗阻后,黄疸成了需首要解决的问题.对于未能行根治手术的患者,胆道支架置入为主的治疗成为缓解梗阻性黄...     

AZ31镁合金材料植入物在兔股骨髁内的降解：Micro-CT评价

BACKGROUND: Magnesium can be degraded voluntarily in vivo, so a second surgery is avoided. However, its alloys have not been widely used in the clinical orthopedics because there is a lack of accurate and reliable methods to assess its degradation in vivo. OBJECTIVE: To explore the degradation of micro-arc-oxidized AZ31 magnesium alloy in the femoral condyle of rabbits based on micro-CT images and relative data. METHODS: Forty micro-arc-oxidized AZ31 magnesium alloys were implanted into the right femoral condyle of 40 New Zealand rabbits. Then 10 right femoral condyles were removed at 5, 10, 15 and 20 weeks after surgery, respectively, to quantitatively analyze and evaluate the degradation of AZ31 magnesium alloys by micro-CT images and relative data. RESULTS AND CONCLUSION: The surface of AZ31 alloys was corroded progressively with dark color and distorted appearance at 5-20 weeks post implantation. Micro-CT images showed that in the first 5 weeks, the degradation was inactive, and at the 10th week, it turned active; at the 15th week, the corrosion pits were obviously increased in number, and the corrosion area and corrosion speed were enlarged and fastened, respectively. Up to the 20th week, the alloy surfaces were full of corrosion pits besides roughness and discontinuity. Relevant data analysis showed that the volume fraction of magnesium alloy was 98.6%, 97.1% and 86.4% at the 5th, 10th and 20th weeks after implantation, respectively, and it had a significant decrease from the 10th to 15th week and from the 15th to 20th week (P < 0.05). Within 15-20 weeks, the volume fraction of magnesium alloy was decreased by 6.5% that was the maximum volume reduction per unit cycle. With the progress of corrosion, the surface continuously became rough and vague, and its surface area was enlarged; the ratio of surface area to volume continuously increased, and there was a significant difference at 15 and 20 weeks (P < 0.05). Because of the increasing number of corrosion pits, the cross-sectional radius decreased, which was reflected by the trabecular thickness decreasing from 1.00 to 0.87 mm. From the view of the slope of curve, the trabecular thickness decreased most rapidly at 10-15 weeks. The mineral density of magnesium alloy continuously decreased from 649.302 to 356.445 mg/cm3 during the whole experiment period (P < 0.05). In addition, the micro-CT image density decreased from 679.710 to 644.947 mg/cm3, but there was no significant difference. To conclude, the degradation speed is peaked at 10-20 weeks after implantation, and the content of magnesium alloys decrease with degradation, but the magnesium density has no significant change. 中国组织工程研究杂志出版内容重点：生物材料;骨生物材料; 口腔生物材料; 纳米材料; 缓释材料; 材料相容性;组织工程     

以专利技术申请信息分析生物可降解镁及镁合金血管支架的现状

BACKGROUND: Research on patented technology plays a real and important role in the technological development and industrial application. OBJECTIVE: To investigate the current patented technologies concerning biodegradable magnesium and magnesium alloy vascular stents. METHODS: We searched the patent applications for biodegradable magnesium and magnesium alloy stents in China, and analyzed relevant information in the following aspects: application trend, authorization trend, applicant geographical distribution, distribution of applicant types, sub-sector patented technology, and patented technology of major applicants. Afterwards, recommendations for patent application in this field could be given. RESULTS AND CONCLUSION: In China, Chinese applicants occupy a dominant position in the patent applications for biodegradable magnesium and magnesium alloy stents, and hot technologies in various sub-sectors are highlighted. Unfortunately, more patented technologies have not achieved a real breakthrough in the application.      

表面改性AZ91D镁合金鼠伤寒沙门氏菌回复突变实验

目的:评价表而改性后的AZ91D镁合金的点突变诱变性.方法:采用微弧氧化方法对AZ91D镁合金进行表面改性.选用组氨酸缺陷型鼠伤寒沙门氏菌TA97、TA98、TA100、TA102菌株,分别设计4个剂量组、自发同变对照组、溶剂对照组以及阳性对照组,采用平板掺入法通过鼠伤寒沙门氏菌回复突变实验(Ames实验),评价微弧氧化AZ91D镁合金是否具有遗传危害和潜在的敛癌作用.结果:材料各剂量组均未引起测试菌株同变菌落数的明显增加.结论:微弧氧化AZ91D镁合金微生物回复突变实验结果为阴性,不具有点突变诱变性.     

镁含量对粉末冶金Ti-Mg合金组织及性能的影响

背景:采用粉末冶金工艺可制备出高强度的钛合金,但制备的合金仍然存在着含有毒元素或弹性模量偏高等问题.目的:制备具有无毒、弹性模量接近于人体骨骼、强度符合人体植入物要求的Ti-Mg合金,并探讨镁含量对合金组织和力学性能的影响.方法:采用粉末冶金工艺将不同质量分数Mg粉与Ti粉进行配比,制备综合性能良好的新型医用Ti-Mg合金.通过光学显微镜、扫描电镜和X射线衍射仪等对烧结体的孔隙率、断口形貌和相组成进行观察,并测试合金的抗弯强度,冲击韧性和硬度等力学性能.结果与结论:随着镁质量分数的增加,容许应变先降低后增加,当镁质量分数为10%时,试样的容许应变为0.97%,最接近于皮质骨的容许应变0.67%;合金的孔隙率从18.3%降到了3.8%,孔洞更加圆滑,孔洞分部更加均匀.且随着镁质量分数的增加,合金的硬度、弯曲强度和模量具有相似的变化规律:即当镁质量分数低于10%时,变化不大,随着镁质量分数的继续增加明显降低,而后趋于稳定.当镁元素质量分数为10%时,合金的硬度、抗弯强度、冲击韧性均满足人体植入的力学性能要求,并且其弯曲模量和容许应变最接近于人体骨骼,显示了较好的生物力学相容性.     

医用可降解镁合金的研究进展

镁合金用于医学领域的研究总体说来还处于探索起步阶段,如何有效控制降解时间,改善力学性能,使其更适合人体生理,是目前研究亟待解决的关键问题。但随着镁合金研究的深入,尤其是材料选择及涂层技术方面的改进,镁合金的降解时间和力学性能的维持时间都有很大的提高。本文对近些年有关镁合金在骨固定材料以及合金支架方面取得的相关成果及主要面临的挑战作一综述。     

纯镁及镁合金材料用于骨组织工程的初步研究

目的探讨纯镁及镁合金材料作为骨组织工程支架材料的可行性。方法通过细胞毒性试验、遗传毒性实验、急性全身毒性试验、血液相容性试验评价材料的安全性。用直接接触的方法,通过AO/EB染色、扫描电镜、ALP活性测定考察材料的生物相容性。结果1%、10%、50%、100%镁及镁合金涂层材料浸提液作用MG63细胞24小时,细胞存活率均大于80%,细胞周期无改变,DNA无损伤。小鼠腹腔注射100%材料浸提液,72小时内无死亡,并且体重与空白对照组比无显著差异。100%纯镁材料浸提液和镁合金材料浸提液的溶血率分别为0.58%和0.33%。细胞复合材料,AO/EB染色观察到细胞在材料表面大量存活,形态正常。扫描电镜结果显示细胞种植于材料表面7天后,可以在材料表面伸展良好,分泌大量的细胞外基质,且ALP活性良好。结论纯镁材料和镁合金材料无细胞毒性和遗传毒性,无急性全身毒性,而不产生溶血现象。与细胞复合后,具有良好的生物相容性。     

Zr对高镁铝合金板材综合性能的影响

铝-镁合金具有良好的耐蚀性、优异的成型性和可焊性,广泛用于军、民用舰船上,但其强度不高。本试验通过在AL-Mg-Mn-Cr合金中加入0.1%～0.2%的Zr后,不仅使合金的强度得到提高,同时Zr还能显著细化晶粒,提高抗剥落腐蚀性,改善压力加工性和焊接性。为高镁铝合金在舰船上使用提供了更加优良的综合性能。