含二氧化钛和银的纳米羟基磷灰石/聚酰胺66复合骨填充材料体外抗菌性能及释放特性的实验研究

Lu Minpeng, Jiang Dianming, Quan Zhengxue, Li Guangzhou, Cao He, Liu Mingfang, Kuang Shangru, Li Jidong, Li Yubao

Department of Orthopedics, the First Affiliated Hospital, Chongqing Medical University, Chongqing, 400016, P.R. China.

Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi. 2010 Jun;24(6):691-5.

OBJECTIVE

Titania and Ag containing nano-hydroxyapatite/polyamide 66 (TiO2-Ag-nHA/PA66) composite bone filling material has good biocompatibility and biological safety. To investigate the antibacterial effect and Ag+ release characteristics of TiO2-Ag-nHA/PA66 composite bone filling material containing different concentrations of Ag+ in vitro.

METHODS

The n-HA/PA66 composite bone filling material A1 (material A1) was prepared by co-polymerization method, and TiO2-Ag-nHA/PA66 composite bone filling materials A2 and A3 (materials A2 and A3) were prepared by the same way containing Ag+ of 0.22wt% and 0.64wt%, respectively, and the TiO2 content was 2.35wt%. The materials A2 and A3 were respectively immersed in 50 mL simulated body fluid (SBF), and Ag+ concentration was measured by atomic absorption spectrometry at 1, 3, 7, 14, 21, and 49 days. The inhibition ring test and colony count method were used to evaluate antibiotic effect against Staphylococcus aureus and Escherichia coli, the anti-adhesion capacity of Staphylococcus aureus and Escherichia coli was observed by scanning electron microscope (SEM).

RESULTS

There was no significant difference in the Ag+ concentration between materials A2 and A3 at 1 day and 3 days (P > 0.05); and there were significant differences in the Ag+ concentration between materials A2 and A3 after 7 days (P < 0.05). The inhibition ring diameters of materials A2 and A3 to Staphylococcus aureus and Escherichia coli reached the maximum at 1 day, which were (13.40 +/- 2.88), (9.40 +/- 1.14) mm and (23.60 +/- 1.14), (18.80 +/- 0.84) mm, showing significant difference (P < 0.05) between materials A2 and A3 respectively; and then, the diameter of inhibition ring reduced with the time. The antibacterial effect of materials A2 and A3 against Staphylococcus aureus and Escherichia coli lasted 15, 33 days and 9, 24 days, respectively. No inhibition ring was observed around material A1 all the time. And the inhibitory rates of materials A2 and A3 were 89.74% +/- 3.62%, 94.18% +/- 2.05% and 78.65% +/- 5.64%, 85.96% +/- 2.50%; showing significant differences (P < 0.05) among materials A1, A2, and A3. SEM showed that bacterial adhesion of materials A2 and A3 was obviously fewer than that of material A1.

CONCLUSION

TiO2-Ag-nHA/PA66 composite bone filling material has antibacterial property against Staphylococcus aureus and Escherichia coli, and it has a good release effect in SBF.

目的

含二氧化钛和银的纳米羟基磷灰石/聚酰胺66（TiO₂-Ag-nHA/PA66）复合骨填充材料具有良好的生物相容性和生物安全性。体外研究不同银离子浓度的TiO₂-Ag-nHA/PA66复合骨填充材料的抗菌效果及银离子释放特性。

方法

采用共聚法制备n-HA/PA66复合骨填充材料A1（材料A1），并采用相同方法制备分别含0.22wt%和0.64wt%银离子、二氧化钛含量为2.35wt%的TiO₂-Ag-nHA/PA66复合骨填充材料A2和A3（材料A2和A3）。将材料A2和A3分别浸泡于50 mL模拟体液（SBF）中，于1、3、7、14、21和49天采用原子吸收光谱法测定银离子浓度。采用抑菌圈试验和菌落计数法评价对金黄色葡萄球菌和大肠杆菌的抗菌效果，通过扫描电子显微镜（SEM）观察金黄色葡萄球菌和大肠杆菌的抗黏附能力。

结果

材料A2和A3在1天和3天时银离子浓度差异无统计学意义（P>0.05）；7天后材料A2和A3的银离子浓度差异有统计学意义（P<0.05）。材料A2和A3对金黄色葡萄球菌和大肠杆菌的抑菌圈直径在1天时达到最大，分别为（13.40±2.88）、（9.40±1.14）mm和（23.60±1.14）、（18.80±0.84）mm，材料A2和A3之间差异有统计学意义（P<0.05）；随后，抑菌圈直径随时间减小。材料A2和A3对金黄色葡萄球菌和大肠杆菌的抗菌效果分别持续15、33天和9、24天。材料A1周围始终未观察到抑菌圈。材料A2和A3的抑菌率分别为89.74%±3.62%、94.18%±2.05%和78.65%±5.64%、85.96%±2.50%；材料A1、A2和A3之间差异有统计学意义（P<0.05）。SEM显示材料A2和A3的细菌黏附明显少于材料A1。