Department of Surgery, Division of General Surgery, Duke University Medical Center, Durham, North Carolina 27710, USA.
Microsc Res Tech. 2010 Jan;73(1):71-6. doi: 10.1002/jemt.20757.
Titanium is one of the most commonly used materials for implantable devices in humans. Scanning electron microscopy (SEM) serves as an important tool for imaging titanium surfaces and analyzing cells and other organic matter adhering to titanium implants. However, high-vacuum SEM imaging of a nonconductive sample requires a conductive coating on the surface. A gold/palladium coating is commonly used and to date no method has been described to "clean" such gold/palladium covered surfaces for repeated experiments without etching the titanium itself. This constitutes a major problem with titanium-based implantable devices which are very expensive and thus in short supply. Our objective was to devise a protocol to regenerate titaniumsurfaces after SEM analysis. In a series of experiments, titanium samples from implantable cardiac assist devices were coated with fibronectin, seeded with cells and then coated with gold/palladium for SEM analysis. X-ray photoelectron spectroscopy spectra were obtained before and after five different cleaning protocols. Treatment with aqua regia (a 1:3 solution of concentrated nitric and hydrochloric acid), with or without ozonolysis, followed by sonication in soap solution and sonication in deionized water, allowed regenerating titanium surfaces to their original state. Atomic force microscopy confirmed that the established protocol did not alter the titanium microstructure. The protocol described herein is applicable to almost all titanium surfaces used in biomedical sciences and because of its short exposure time to aqua regia, will likely work for many titanium alloys as well.
钛是人类植入装置中最常用的材料之一。扫描电子显微镜（SEM）是用于成像钛表面以及分析附着在钛植入物上的细胞和其他有机物质的重要工具。然而，对非导电样品进行高真空 SEM 成像需要在表面上进行导电涂层。金/钯涂层是常用的，迄今为止，还没有描述过一种方法可以在不腐蚀钛本身的情况下，对重复实验用的金/钯覆盖表面进行“清洁”。这是钛基植入式装置的一个主要问题，因为这些装置非常昂贵，因此供应短缺。我们的目标是设计一种方案，在 SEM 分析后再生钛表面。在一系列实验中，从植入式心脏辅助装置的钛样本上涂覆纤维连接蛋白，接种细胞，然后涂覆金/钯进行 SEM 分析。在五种不同清洗方案前后获得了 X 射线光电子能谱谱。用王水（浓硝酸和盐酸 1:3 的溶液）处理，臭氧氧化，然后在肥皂溶液中进行超声处理和在去离子水中进行超声处理，可以使钛表面恢复到原始状态。原子力显微镜证实，所建立的方案没有改变钛的微观结构。本文描述的方案适用于生物医学科学中使用的几乎所有钛表面，由于其短时间接触王水，可能也适用于许多钛合金。
