Department of Materials Science and Engineering, Institute of Biomaterials, University of Erlangen-Nuremberg, Cauerstr.6, 91058 Erlangen, Germany.
Institute of Physics of Materials ASCR, CEITEC IPM, Žižkova 22, 61662 Brno, Czech Republic.
Int J Mol Sci. 2020 Apr 10;21(7):2637. doi: 10.3390/ijms21072637.
Bacterial infection associated with medical implants is a major threat to healthcare. This work reports the fabrication of Copper(II)-Chitosan (Cu(II)-CS) complex coatings deposited by electrophoretic deposition (EPD) as potential antibacterial candidate to combat microorganisms to reduce implant related infections. The successful deposition of Cu(II)-CS complex coatings on stainless steel was confirmed by physicochemical characterizations. Morphological and elemental analyses by scanning electron microscopy (SEM) and energy-dispersive X-ray (EDX) spectroscopy verified the uniform distribution of copper in the Chitosan (CS) matrix. Moreover, homogeneous coatings without precipitation of metallic copper were confirmed by X-ray diffraction (XRD) spectroscopy and SEM micrographs. Controlled swelling behavior depicted the chelation of copper with polysaccharide chains that is key to the stability of Cu(II)-CS coatings. All investigated systems exhibited stable degradation rate in phosphate buffered saline (PBS)-lysozyme solution within seven days of incubation. The coatings presented higher mechanical properties with the increase in Cu(II) concentration. The crack-free coatings showed mildly hydrophobic behavior. Antibacterial assays were performed using both Gram-positive and Gram-negative bacteria. Outstanding antibacterial properties of the coatings were confirmed. After 24 h of incubation, cell studies of coatings confirms that up to a certain threshold concentration of Cu(II) were not cytotoxic to human osteoblast-like cells. Overall, our results show that uniform and homogeneous Cu(II)-CS coatings with good antibacterial and enhanced mechanical stability could be successfully deposited by EPD. Such antibiotic-free antibacterial coatings are potential candidates for biomedical implants.
医用植入物相关的细菌感染是对医疗保健的重大威胁。本工作报道了通过电泳沉积（EPD）制备铜（II）-壳聚糖（Cu（II）-CS）复合涂层，作为潜在的抗菌候选物，以对抗微生物，减少与植入物相关的感染。通过物理化学特性证实了 Cu（II）-CS 复合涂层在不锈钢上的成功沉积。扫描电子显微镜（SEM）和能谱（EDX）的形貌和元素分析证实了铜在壳聚糖（CS）基质中的均匀分布。此外，X 射线衍射（XRD）光谱和 SEM 显微照片证实了没有金属铜沉淀的均匀涂层。控制溶胀行为描绘了铜与多糖链的螯合，这是 Cu（II）-CS 涂层稳定性的关键。所有研究的系统在孵育七天内的磷酸盐缓冲盐水（PBS）-溶菌酶溶液中均表现出稳定的降解率。随着 Cu（II）浓度的增加，涂层表现出更高的机械性能。无裂纹的涂层表现出轻度疏水性。使用革兰氏阳性和革兰氏阴性细菌进行了抗菌试验。证实了涂层具有出色的抗菌性能。孵育 24 h 后，涂层的细胞研究证实，在一定的 Cu（II）阈值浓度下，对人成骨样细胞没有细胞毒性。总体而言，我们的结果表明，通过 EPD 可以成功沉积具有良好抗菌性和增强机械稳定性的均匀和均匀的 Cu（II）-CS 涂层。这种无抗生素的抗菌涂层是生物医学植入物的潜在候选材料。
