Department of Bioengineering, University of California, Riverside, 900 University Avenue, Riverside, CA 92521, USA.
J Mater Sci Mater Med. 2013 Feb;24(2):307-16. doi: 10.1007/s10856-012-4796-y. Epub 2012 Oct 27.
In an attempt to develop biodegradable, mechanically strong, biocompatible, and conductive nerve guidance conduits, pure magnesium (Mg) was used as the biodegradable substrate material to provide strength while the conductive polymer, poly(3,4-ethylenedioxythiophene) (PEDOT) was used as a conductive coating material to control Mg degradation and improve cytocompatibility of Mg substrates. This study explored a series of electrochemical deposition conditions to produce a uniform, consistent PEDOT coating on large three-dimensional Mg samples. A concentration of 1 M 3,4-ethylenedioxythiophene in ionic liquid was sufficient for coating Mg samples with a size of 5 × 5 × 0.25 mm. Both cyclic voltammetry (CV) and chronoamperometry coating methods produced adequate coverage and uniform PEDOT coating. Low-cost stainless steel and copper electrodes can be used to deposit PEDOT coatings as effectively as platinum and silver/silver chloride electrodes. Five cycles of CV with the potential ranging from -0.5 to 2.0 V for 200 s per cycle were used to produce consistent coatings for further evaluation. Scanning electron micrographs showed the micro-porous structure of PEDOT coatings. Energy dispersive X-ray spectroscopy showed the peaks of sulfur, carbon, and oxygen, indicating sufficient PEDOT coating. Adhesion strength of the coating was measured using the tape test following the ASTM-D 3359 standard. The adhesion strength of PEDOT coating was within the classifications of 3B to 4B. Tafel tests of the PEDOT coated Mg showed a corrosion current (I(CORR)) of 6.14 × 10(-5) A as compared with I(CORR) of 9.08 × 10(-4) A for non-coated Mg. The calculated corrosion rate for the PEDOT coated Mg was 2.64 mm/year, much slower than 38.98 mm/year for the non-coated Mg.
为了开发可生物降解、机械强度高、生物相容性好、导电性好的神经引导导管，本研究使用纯镁 (Mg) 作为可生物降解的基底材料，以提供强度，而将导电聚合物聚(3,4-亚乙基二氧噻吩) (PEDOT) 用作导电涂层材料，以控制 Mg 的降解并提高 Mg 基底的细胞相容性。本研究探索了一系列电化学沉积条件，以在大型三维 Mg 样品上制备均匀、一致的 PEDOT 涂层。在离子液体中浓度为 1 M 的 3,4-亚乙基二氧噻吩足以涂覆尺寸为 5×5×0.25 mm 的 Mg 样品。循环伏安法 (CV) 和计时安培法两种涂层方法都能得到足够的覆盖和均匀的 PEDOT 涂层。低成本的不锈钢和铜电极可以像铂和银/氯化银电极一样有效地沉积 PEDOT 涂层。使用电位范围为 -0.5 至 2.0 V 的 CV 进行 5 个循环，每个循环 200 s，以产生进一步评估的一致涂层。扫描电子显微镜照片显示了 PEDOT 涂层的微多孔结构。能谱分析显示了硫、碳和氧的峰值，表明 PEDOT 涂层充足。使用 ASTM-D 3359 标准的胶带试验测量涂层的附着力。PEDOT 涂层的附着力符合 3B 至 4B 的分类。PEDOT 涂层的 Mg 的 Tafel 测试显示腐蚀电流 (I(CORR))为 6.14×10(-5) A，而未涂层的 Mg 的 I(CORR)为 9.08×10(-4) A。计算得出 PEDOT 涂层的 Mg 的腐蚀速率为 2.64 mm/年，远低于未涂层的 Mg 的 38.98 mm/年。
