Abstract：
Ultraviolet (UV) photofunctionalization counteracts the biological aging of titanium to increase the bioactivity and osseointegration of titanium implants. However, UV photofunctionalization currently requires long treatment times of between 12 min and 48 h, precluding routine clinical use. Here, we tested the ability of a novel, xenon excimer lamp emitting 172 nm vacuum UV (VUV) to decompose organic molecules coated on titanium as a surrogate of photofunctionalization. Methylene blue as a model organic molecule was coated on grade 4 commercially pure titanium and treated with four UV light sources: (i) ultraviolet C (UVC), (ii) high-energy UVC (HUVC), (iii) proprietary UV (PUV), and (iv) VUV. After one minute of treatment, VUV decomposed 57% of methylene blue compared with 2%, 36%, and 42% for UVC, HUVC, and PUV, respectively. UV dose-dependency testing revealed maximal methylene blue decomposition with VUV within one minute. Equivalent decomposition was observed on grade 5 titanium alloy specimens, and placing titanium specimens in quartz ampoules did not compromise efficacy. Methylene blue was decomposed even on polymethyl methacrylate acrylic specimens at 20-25% lower efficiency than on titanium specimens, indicating a relatively small contribution of titanium dioxide-mediated photocatalytic decomposition to the total decomposition. Load-testing revealed that VUV maintained high efficacy of methylene blue decomposition regardless of the coating density, whereas other UV light sources showed low efficacy with thin coatings and plateauing efficacy with thicker coatings. This study provides foundational data on rapid and efficient VUV-mediated organic decomposition on titanium. In synergy with quartz ampoules used as containers, VUV has the potential to overcome current technical challenges hampering the clinical application of UV photofunctionalization.
摘要：
紫外线（UV）光功能化抵消钛的生物老化，以增加钛植入物的生物活性和骨整合。然而,紫外光功能化目前需要12分钟至48小时的长处理时间，排除常规临床使用。这里,我们测试了小说的能力，氙气准分子灯发射172nm真空UV（VUV），以分解涂覆在钛上的有机分子作为光功能化的替代品。将作为模型有机分子的亚甲基蓝涂覆在4级商业纯钛上，并用四个UV光源处理：（i）紫外线C（UVC），（ii）高能UVC（HUVC），(iii)专有UV(PUV)，和(iv)VUV。经过一分钟的治疗，VUV分解57%的亚甲基蓝比拟2%，36%,UVC为42%，HUVC,还有PUV,分别。UV剂量依赖性测试揭示了在一分钟内使用VUV的最大亚甲基蓝分解。在5级钛合金试样上观察到等效分解，并将钛标本放在石英安瓿中不会影响功效。即使在聚甲基丙烯酸甲酯丙烯酸样品上，亚甲基蓝的分解效率也比钛样品低20-25％，表明二氧化钛介导的光催化分解对总分解的贡献相对较小。负载测试表明，无论涂层密度如何，VUV都能保持高的亚甲基蓝分解效率，而其他紫外线光源在薄涂层下显示出低功效，而在较厚涂层下显示出稳定的功效。这项研究提供了快速有效的VUV介导的钛有机分解的基础数据。与用作容器的石英安瓿协同作用，VUV具有克服阻碍UV光功能化的临床应用的当前技术挑战的潜力。
