Physics Department, Brown University, Providence, Rhode Island 02912, USA.
J Biomed Mater Res A. 2010 Jun 15;93(4):1417-28. doi: 10.1002/jbm.a.32631.
Current orthopedic implants have several problems that include poor osseointegration for extended periods of time, stress shielding and wear debris-associated bone cell death. In addition, numerous patients receive orthopedic implants as a result of bone cancer resection, yet current orthopedic materials were not designed to prevent either the occurrence or reoccurrence of cancer. The objective of this in vitro study was to create a new biomaterial which can both restore bone and prevent cancer growth at the implant-tissue interface. Elemental selenium was chosen as the biologically active agent in this study because of its known chemopreventive and chemotherapeutic properties. It was found that when selenite salts were reduced by glutathione in the presence of an immersed titanium substrate, elemental selenium nucleated and grew into adherent, hemispherical nanoclusters that formed a nanostructured composite surface. Three types of surfaces with different selenium surface densities on titanium were fabricated and confirmed by SEM images, AFM, and XPS profiles. Compared to conventional untreated titanium, a high-density selenium-doped surface inhibited cancerous bone cell proliferation while promoting healthy bone cell functions (including adhesion, proliferation, alkaline phosphatase activity and calcium deposition). These findings showed for the first time the potential of selenium nanoclusters as a chemopreventive titanium orthopedic material coating that can also promote healthy bone cell functions.
目前的骨科植入物存在一些问题，包括长时间的骨整合不良、应力遮挡和与磨损颗粒相关的骨细胞死亡。此外，许多患者因骨癌切除而接受骨科植入物治疗，但目前的骨科材料并未设计用于预防癌症的发生或复发。本体外研究的目的是开发一种新的生物材料，既能修复骨骼，又能预防植入物-组织界面的癌症生长。本研究选择元素硒作为生物活性物质，因为它具有已知的化学预防和化疗特性。研究发现，当亚硒酸盐在浸入钛基底的谷胱甘肽存在下被还原时，元素硒成核并生长成附着的、半球形的纳米团簇，形成纳米结构的复合表面。通过 SEM 图像、AFM 和 XPS 谱图证实，在钛上制备了三种具有不同硒表面密度的表面。与传统的未处理钛相比，高密度硒掺杂表面抑制了癌细胞的增殖，同时促进了健康骨细胞的功能（包括粘附、增殖、碱性磷酸酶活性和钙沉积）。这些发现首次表明硒纳米团簇作为一种化学预防钛骨科材料涂层的潜力，它还可以促进健康骨细胞的功能。
