Biomedical Engineering Program, The University of South Dakota, Sioux Falls, South Dakota 57107, United States.
Langmuir. 2012 Aug 7;28(31):11511-26. doi: 10.1021/la301636z. Epub 2012 Jul 26.
Cobalt-chromium (Co-Cr) alloys have extensive biomedical applications including drug-eluting stents (DES). This study investigates the use of eight different microrough Co-Cr alloy surfaces for delivering paclitaxel (PAT) for potential use in DES. The eight different surfaces include four bare microrough and four self-assembled monolayer (SAM) coated microrough surfaces. The bare microrough surfaces were prepared by grit blasting Co-Cr with glass beads (50 and 100 μm in size) and Al(2)O(3) (50 and 110 μm). The SAM coated surfaces were prepared by depositing a -COOH terminated phosphonic acid monolayer on the different microrough surfaces. PAT was then deposited on all the bare and SAM coated microrough surfaces. The surfaces were characterized using scanning electron microscopy (SEM), 3D optical profilometry, and Fourier transform infrared spectroscopy (FTIR). SEM showed the different morphologies of microrough surfaces without and with PAT coating. An optical profiler showed the 3D topography of the different surfaces and the changes in surface roughness and surface area after SAM and PAT deposition. FTIR showed ordered SAMs were formed on glass bead grit blasted surfaces, while the molecules were disordered on Al(2)O(3) grit blasted surfaces. Also, FTIR showed the successful deposition of PAT on these surfaces. The PAT release was investigated for up to two weeks using high performance liquid chromatography. Al(2)O(3) grit blasted bare microrough surfaces showed sustained release profiles, while the glass bead grit blasted surfaces showed burst release profiles. All SAM coated surfaces showed biphasic drug release profiles, which is an initial burst release followed by a slow and sustained release. SAM coated Al(2)O(3) grit blasted surfaces prolonged the sustained release of PAT in a significant amount during the second week of drug elution studies, while this behavior was not observed for any other surfaces used in this study. Thus, this study demonstrates the use of different microrough Co-Cr alloy surfaces for delivering PAT for potential applications in DES and other medical devices.
钴铬（Co-Cr）合金在生物医学领域有广泛的应用，包括药物洗脱支架（DES）。本研究旨在探索八种不同的微粗糙 Co-Cr 合金表面用于递送紫杉醇（PAT）的可能性，以应用于 DES 及其他医疗器械。这八种不同的表面包括四种裸微粗糙表面和四种自组装单分子层（SAM）涂覆的微粗糙表面。裸微粗糙表面通过用玻璃珠（粒径为 50 和 100μm）和 Al2O3（粒径为 50 和 110μm）对 Co-Cr 进行喷丸处理来制备。SAM 涂覆表面通过将 -COOH 端基膦酸单层沉积在不同的微粗糙表面上来制备。然后将 PAT 沉积在所有裸微粗糙和 SAM 涂覆的微粗糙表面上。通过扫描电子显微镜（SEM）、三维光学轮廓仪和傅里叶变换红外光谱（FTIR）对表面进行了表征。SEM 显示了具有和不具有 PAT 涂层的微粗糙表面的不同形貌。光学轮廓仪显示了不同表面的三维形貌以及 SAM 和 PAT 沉积后表面粗糙度和表面积的变化。FTIR 表明，玻璃珠喷丸处理的表面形成了有序的 SAM，而 Al2O3 喷丸处理的表面上分子则无序排列。此外，FTIR 表明 PAT 成功地沉积在这些表面上。通过高效液相色谱法研究了 PAT 的释放情况，长达两周。Al2O3 喷丸处理的裸微粗糙表面显示出持续释放的曲线，而玻璃珠喷丸处理的表面则显示出突释释放的曲线。所有 SAM 涂覆的表面均显示出双相药物释放曲线，即初始突释释放后缓慢持续释放。SAM 涂覆的 Al2O3 喷丸处理表面在药物洗脱研究的第二周显著延长了 PAT 的持续释放量，而在本研究中使用的其他表面上未观察到这种行为。因此，本研究证明了使用不同的微粗糙 Co-Cr 合金表面递送 PAT 的可能性，以应用于 DES 和其他医疗器械。
