Cai Kaiyong, Hu Yan, Wang Yuanliang, Yang Li
College of Bioengineering, Chong Qing University, Chong Qing 400044, People's Republic of China.
J Biomed Mater Res A. 2008 Feb;84(2):516-22. doi: 10.1002/jbm.a.31458.
In an effort to surface engineering of poly(D,L-lactic acid) (PDLLA), layer-by-layer (LbL) self-assembly of chitosan (Chi) and deoxyribonucleic acid (DNA) were employed to build up multilayered films. The formation of multilayers was monitored by using Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), water contact-angle measurement, and atomic force microscopy (AFM), respectively. A full coverage of Chi/DNA pair film was formed only after the fifth sequential deposition (PEI/(DNA/Chi)2), which was revealed by contact-angle measurement. Surface chemistry and topography of multilayered films were directly related to the corresponding outmost layer component. Discernable island-like structures on PEI/(DNA/Chi)5/DNA layered PDLLA film was observed. Lysozyme-mediated multilayer degradation and DNA-releasing measurement suggested that DNA was gradually released into the incubation medium over a period of up to 32 h. The approach presented here may be exploited to develop controlled administration of functional DNA constructs from the surfaces of biomedical materials and devices in situ.
为了对聚（D，L-乳酸）（PDLLA）进行表面工程，采用壳聚糖（Chi）和脱氧核糖核酸（DNA）的层层（LbL）自组装来构建多层膜。分别使用傅里叶变换红外光谱（FTIR）、X射线光电子能谱（XPS）、水接触角测量和原子力显微镜（AFM）监测多层膜的形成。通过接触角测量发现，仅在第五次顺序沉积（PEI/（DNA/Chi）2）后才形成了完全覆盖的Chi/DNA对膜。多层膜的表面化学和形貌与相应的最外层成分直接相关。在PEI/（DNA/Chi）5/DNA层状PDLLA膜上观察到了明显的岛状结构。溶菌酶介导的多层降解和DNA释放测量表明，在长达32小时的时间内，DNA逐渐释放到孵育介质中。本文提出的方法可用于开发从生物医学材料和装置表面原位控制功能性DNA构建体给药的方法。
