Department of Polymer Science and Materials, Sichuan University, State Key Laboratory of Polymer Materials Engineering, Chengdu 610065, China.
Colloids Surf B Biointerfaces. 2011 Aug 1;86(1):189-97. doi: 10.1016/j.colsurfb.2011.03.041. Epub 2011 Apr 5.
Ultrasonication is often used to disperse nano-particles in aqueous solution. However, a good dispersion of nano-particles in aqueous solution is not always achieved, due to the fact that incoming ultrasonicwaves in liquid are usually reflected and damped at the gas/liquid interface. In this work, we report a so-called wet-grinding assisted ultrasonication (GU) method, in which wet-grinding of multi-walled carbon nanotubes (MWCNTs) in chitosan solution is carried out before ultrasonication. The dispersions of MWCNTs were characterized by visual comparison, UV/vis spectroscopy, and scanning electron microscopy (SEM). The results demonstrate that the dispersion quality of chitosan/MWCNT suspension prepared by wet-grinding assisted ultrasonication is much better than that by ultrasonication or wet-grinding alone. It was found that wet-grinding could improve the water wettability of MWCNTs and eliminate the barrier of air layer around MWCNTs to ultrasonicwaves. Meanwhile, the composite from the chitosan/MWCNTs suspension prepared by GU method has an obvious improvement in mechanical property compared to pure chitosan. This simple method for integrating MWCNTs and biocompatible chitosan into a homogeneous dispersion may have great potential application in biotechnology, such as preparing composite materials for medicine, bio-fiber, biosensor, antibacterial coating, and cell cultivation.
超声处理通常用于在水溶液中分散纳米颗粒。然而，由于进入液体的超声波在气/液界面通常会被反射和阻尼，因此并不总是能在水溶液中实现纳米颗粒的良好分散。在这项工作中，我们报告了一种所谓的湿磨辅助超声（GU）方法，其中在超声处理之前，在壳聚糖溶液中进行多壁碳纳米管（MWCNT）的湿磨。通过视觉比较、紫外/可见光谱和扫描电子显微镜（SEM）对 MWCNT 的分散体进行了表征。结果表明，通过湿磨辅助超声处理制备的壳聚糖/MWCNT 悬浮液的分散质量明显优于单独超声处理或湿磨处理的分散质量。研究发现，湿磨可以提高 MWCNTs 的亲水性，并消除 MWCNTs 周围空气层对超声波的阻碍。同时，与纯壳聚糖相比，GU 法制备的壳聚糖/MWCNTs 悬浮液的复合材料在机械性能方面有明显的提高。这种将 MWCNTs 和生物相容性壳聚糖集成到均匀分散体中的简单方法，在生物技术领域可能具有很大的潜在应用，如制备用于药物、生物纤维、生物传感器、抗菌涂层和细胞培养的复合材料。
