The anti-oxidative properties of α-tocopherol in γ-irradiated UHMWPE with respect to fatigue and oxidation resistance
The anti-oxidative properties of α-tocopherol in γ-irradiated UHMWPE with respect to fatigue and oxidation resistance
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DOI：
10.1016/j.biomaterials.2005.02.035
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发表时间：
2005-10-01
期刊：
影响因子：
14
通讯作者：
Tomita, N
中科院分区：
文献类型：
--
作者：
Shibata, N;Tomita, N
尽管据报道添加抗氧化剂（α-生育酚）可防止超高分子量聚乙烯（UHMWPE）膝关节部件分层，但α-生育酚作为抗氧化剂对UHMWPE长期疲劳性能改善的作用机制尚不清楚。为了解决这一问题，对伽马辐照（25 kGy）、添加0.3 wt% α-生育酚的伽马辐照（25 kGy）和添加0.3 wt%醋酸生育酚的伽马辐照（25 kGy）UHMWPE样本进行了双向滑动疲劳测试。用扫描声断层成像（SAT）对内部缺陷的形成进行量化。此外，氧化指数和结晶度，获得从红外吸收光谱测量使用傅里叶变换红外（FT-IR）显微镜。仅伽马辐照UHMWPE样本导致严重疲劳断裂。添加α-生育酚的UHMWPE样本的缺陷投影面积比（1.80 +/- 0.82）显著低于伽马辐照样本（7.0 +/- 2.29）和添加生育酚乙酸酯样本（8.50 +/- 2.01）。与掺杂样品相比，伽马辐照UHMWPE样品的氧化指数（0.111 +/- 0.0052）极高;添加α-生育酚和添加生育酚乙酸酯的样品分别为0.0179 +/- 0.0026和0.0144 +/- 0.0069。与掺杂样品相比，经T辐照的UHMWPE样品的结晶度（57.5 +/- 1.16）较低;添加α-生育酚和添加生育酚乙酸酯的样品的结晶度分别为60.3 +/- 0.72和60.4 +/- 1.38。α-生育酚的加入显著改善了经γ辐照的UHMWPE的长期疲劳性能（具有氧化稳定性）。此外，α-生育酚的添加控制了大分子结构，从而改善了UHMWPE的疲劳性能。(c)2005爱思唯尔有限公司保留所有权利。
Although addition of an antioxidant (alpha-tocopherol) is reported to prevent delamination in ultrahigh molecular weight polyethylene (UHMWPE) knee components, contribution of alpha-tocopherol as an antioxidant to the improvement of long-term fatigue performance of UHMWPE is an unknown mechanism. To solve this problem, bi-directional sliding fatigue tests were performed for gamma-irradiated (25 kGy), gamma-irradiated (25 kGy) with 0.3 wt% alpha-tocopherol added, and gamma-irradiated (25 kGy) with 0.3 wt% tocopheryl acetate added UHMWPE specimens. Internal defect initiation was quantified with scanning acoustic tomography (SAT). Also, oxidation index and crystallinity were obtained from infrared absorption spectra measured using Fourier transform infrared (FT-IR) microscopy. Only gamma-irradiated UHMWPE specimens resulted in severe fatigue fractures. alpha-Tocopherol-added UHMWPE specimens showed significantly lower projected area ratio of defects (1.80 +/- 0.82) than did gamma-irradiated (7.0 +/- 2.29) and tocopheryl acetate-added ones (8.50 +/- 2.01). The oxidation index of gamma-irradiated UHMWPE specimens (0.111 +/- 0.0052) was extremely higher, compared to those of doped ones; 0.0179 +/- 0.0026 and 0.0144 +/- 0.0069 for a-tocopherol-added and tocopheryl acetate-added ones, respectively. The crystallinity of T-irradiated UHMWPE specimens (57.5 +/- 1.16) was lower compared to those of doped ones; 60.3 +/- 0.72 and 60.4 +/- 1.38 for alpha-tocopherol-added and tocopheryl acetate-added ones, respectively. The incorporation of a-tocopherol significantly improves the long-term fatigue performance of y-irradiated UHMWPE with oxidation stability. Also, the addition of alpha-tocopherol controls macromolecular structures resulting in the improvement of fatigue performance of UHMWPE. (c) 2005 Elsevier Ltd. All rights reserved.