摘要
目的 评价自制的新型骨科生物复合材料——二氧化锆(Zirconia,ZrO2)梯度复合羟基磷灰石(hydroxyapatite,HA)的生物相容性和安全性。方法用化学沉淀法制备Zr02超细粉和HA粉体后,采用干铺-烧结法制备ZrO2梯度复合HA的新型生物复合材料,分别行以下实验:①小鼠急性毒性实验分2组(n=10),分别按50g/kg注射材料浸提液和生理盐水,观察小鼠毒性表现、死亡数和体重变化。②建立L929细胞生长代谢标准曲线。③细胞毒性实验分3组:材料组(材料浸提液)、阳性对照组(0.64%苯酚的培养液)和阴性对照组(RPMI-1640培养液),分别与细胞悬液培养,行细胞形态学观察和相对增殖率(relative proliferation rate,RGR)计算及毒性分级。④体外溶血实验分3组,分别取10ml材料浸提液、灭菌蒸馏水(阳性对照组)和0.9%生理盐水(阴性对照组),各加入抗凝稀释新鲜兔血0.2ml,测定溶血率。⑤骨和肌肉内植入实验分4组(n=3),分别于双侧臀部肌肉和股骨外髁处植入生物复合材料,于术后3、6、12和24周处死动物,分别作组织切片和电镜扫描。结果①全身急性毒性实验:3周内小鼠无死亡;3d内各组动物未见中毒症状或不良反应;材料组体重增长3.57±0.49g,对照组为3.62±0.61g,差异无统计学意义(P〉0.05)。②L929细胞生长代谢标准曲线表明,L929细胞接种量与细胞的增殖代谢率在接种细胞数为1~8×10^3个/孔范围内呈正直线相关。③细胞毒性实验:阳性对照组细胞体变小成圆形,核固缩,贴壁细胞聚集成团,毒性级为N级;材料组和阴性对照组细胞形态正常,数量增多,毒性级分别为Ⅰ级和0级;MTT比色法检测,阳性对照组明显低于材料组和阴性对照组,差异有统计学意义(P〈0.01);阴性对照组与材料组间差异无统计学意义(P〉0.05)。④溶血实验:阴性对照组的体外溶血率为0,阳性对照组体外溶血率为100%,而材料组的体外溶血率为1.66%,符合ISO规定的溶血率〈5%的标准。⑤兔肌肉和骨内植入实验:植入体内后,无明显异物反应;材料与受体骨发生牢固的生物键合,具有良好的骨诱导作用。结论ZrO2梯度复合HA生物复合材料具有良好的生物相容性,适合作为生物骨科材料。
Objective To evaluate the biocompatibility and safety of a novel orthopedics materials-graded zirconia(ZrO2)-hydroxyapatite(HA) composite biomaterials. Methods First, ultrafine powers of ZrO2 and HA powder were prepared by chemical precipitation method, then graded ZrO2-HA composite was synthesized by dry-laying and sintering method. After the physiological saline and culture medium extracts of the composite were prepared, four experiments were conducted as follows :① The mouse acute toxic test consists of 2 groups (n=10). The extracts were intravenously injected to mice in the first group, and physiological saline to mice in the second group. The dose was 50 g/kg. Their toxicity manifestation, morality and the change of weight were recorded. ② The standard curve of proliferation and metabolism of L929 cells was established. ③ The cytotoxinic test consists of 3 groups : materials group (extracts of the materials), positive control group (culture fluid with 0. 64% phenol), and negative control group (RPMI-1640 culture fluid). Each of three was cultured with cell suspension, and then the morphology of the cells was observed, the relative proliferation rate (RGR) was calculated, and the toxicity was classified. ④ In vitro hemolytic test was divided into 3 groups: extracts, sterile distilled water (positive control) and 0. 9% physiological saline. In each of three, 0. 2 ml anticoagulant diluted fresh rabbit blood was added. The percentage of hemolysis was tested. ⑤ The muscle and implantation test were divided into 4 groups(n=3). The composite biomaterials were implanted into pygal muscles on either side and lateral condyles of femurs. After surgery, the rats of four groups were sacrificed at 3, 6,12 and 24 weeks respectively. Tissue slice and scanning electronic microscopy were performed. Results ① General acute toxic test : no mouse died within 3 weeks ; no toxicity symptom or adverse effects were shown within 3 days. The weight of materials group increased by 3. 575=0.49 g, and the control group by 3. 625=0. 61 g, showing no statistically significant difference(P〉0.05). The standard curve of L929 cell perliferation and metabolism showed that their existed a positive correlation between the number of L929 cells and the perliferation. ② Cytotoxinic test : cytosomes in the positive control group diminished and appeared round, there were pyknotie nucleus, the attached cells agglomerated; the toxicity was level Ⅳ. The morphology of cells in materials group and negative control group was normal, and the number of them increased; the toxicity was level I and level 0, respectively. The MTT color experiments showed that positive control group was significantly lower than materials group and negative control group, showing statistically significant difference (P〈0. 01); there was no statistically significant difference between materials group and negative group. ③ Hemolytic test : in vitro hemolytic rate of negative control group was 0, of positive control group was 100%, and of materials group was 1. 66%, which accords with the standard that hemolytic rate should be lower than 5% specified in ISO.④ Implant test:No apparent rejection reaction took place after the composite was implanted; the composite bonded with the bones of the receptors firmly, which had good boned-induced effect. Conclusion Graded ZrO2-HA composite bioeeramie has good bioeompatibility and is suitable for orthopedic biomaterials.
出处
《中国修复重建外科杂志》
CAS
CSCD
北大核心
2006年第5期569-573,共5页
Chinese Journal of Reparative and Reconstructive Surgery
基金
浙江省科技计划资助项目(021103026)~~