钛表面ALD构建氧化锌纳米薄膜及其性能研究

The properties of ZnO nanofilms on titanium surface by atomic layer deposition

目的 比较研究原子层沉积法(atomic layer deposition, ALD)不同沉积周期制备氧化锌(ZnO)纳米薄膜的理化特点及其抗菌效应。方法 根据不同的沉积周期,将实验分为4组(光滑钛组、300循环组、600循环组、1 200循环组)。以二乙基锌、水为前驱体,在纯钛试件表面利用ALD技术制备氧化锌纳米薄膜。采用扫描电子显微镜(SEM)观察薄膜表面形貌,能谱仪(EDS)和X射线衍射仪(XRD)检测薄膜的元素组成和晶型,水接触角检测仪检测薄膜的亲水性,椭偏仪检测镀膜厚度。通过CCK-8实验、光密度法评估薄膜的细胞毒性及其对金黄色葡萄球菌的体外抗菌效果。结果 SEM结果显示ALD在纯钛表面制备的薄膜均匀致密,晶粒尺寸随着沉积周期增加而增大,EDS、XRD结果显示镀膜主要由Zn、O元素构成,成分为氧化锌晶体。水接触角结果显示薄膜为疏水。椭偏仪结果显示各实验组薄膜厚度为纳米级,与沉积周期之间呈线性关系。各实验组均未表现出细胞毒性,具有体外抗金黄色葡萄球菌效果,1 200循环组在24、48 h表现出最高抗菌率,分别为65.9%和52.3%,效果最佳。结论 ALD法在纯钛表面制备的不同沉积周期的氧化锌纳米薄膜均匀、致密,厚度随沉积周期数增加而增厚,具有良好的生物相容性和体外抗金黄色葡萄球菌效应,且1 200循环组抗菌效果最佳。

Objective To compare and investigate the physicochemical characteristics and antibacterial effect of ZnO nanofilms prepared by atomic layer deposition(ALD) at different deposition cycles. Methods According to different ALD cycles, four groups were set up(control group, 300, 600 and 1 200 cycles group). Using DEZn and water as precursors, ZnO nanofilms were prepared by ALD on the surface of pure titanium specimens. Surface morphology of the films was observed by scanning electron microscope(SEM);the element composition and crystal type of the films were observed by energy dispersive spectrometer(EDS) and X-Ray Diffraction(XRD);the hydrophilicity and thickness of the films were detected by water contact angle detector and ellipsometer. The cytotoxicity of the films was evaluated by CCK-8 assay. The antibacterial effect against S. aureus in vitro of the films was evaluated by optical density method. Results The surface morphology of the films was uniform and compact as shown through SEM. The grain size increased with the increase of the number of ALD cycles. EDS results showed that the films were mainly composed of Zn and O elements. XRD results confirmed that the composition of the films was ZnO. Results of water contact angle showed that the films were hydrophobic. The thickness of the films was nanoscale and there was a linear relationship between the thickness and ALD cycles. All experimental groups showed no cytotoxicity. The 1 200 cycles group showed the highest antibacterial rate of 65.9% and 52.3% at 24 and 48 hours respectively, which was the best among all experimental groups. Conclusion The ZnO nanofilms prepared by ALD at different cycles on pure titanium surface are uniform and compact. Thickness of the films increases with the increase of ALD cycles. The films have good biocompatibility and anti-S. aureus effect in vitro. The 1 200 cycles group has the best antibacterial effect.