RGD肽自组装多层膜修饰钛表面的研究

Surface Modification of Titanium by RGD Peptide Self-assembling Multilayers

目的利用层层自组装技术,在钛表面构建RGD肽(Arg-Gly-Asp Peptides)多层膜,评价其血液相容性,探讨该技术在医用金属表面改性领域内的应用前景。方法采用氢氧化钠(NaOH)预先处理钛试件,获得多孔、负电荷的钛表面,吸附一层正电荷的聚乙烯亚胺,然后多次交替吸附RGD肽,形成RGD肽的多层膜结构。通过对该涂层进行物理表征测定及体外血液相容性检测,评价其血液相容性。结果 RGD肽自组装多层膜表面水接触角为78.21±1.98°,体外溶血率为0.76%,该涂层还可有效延长部分活化凝血酶原时间(APTT)至(15.1±0.2)s,并且能够有效抑制血小板的粘附与激活。结论利用层层自组装技术形成的RGD肽涂层血液相容性高,有望成为一种新型的生物化钛表面,显示了其在医用金属表面改性领域的广阔应用前景。

Objective To establish RGD peptide multilayers on the surface of titanium by layer-by-layer（LBL）self-assembling technique,and to explore the blood compatibility of this titanium and its application in the area of medical metal surface modification.Methods The porous and negatively charged surface of titanium was obtained by pretreatment of titanium with NaOH,which absorbed one layer of positive charged PEI and then alternately RGD peptide to form the multilayer structure of RGD peptide.The blood compatibility of the pure titanium with RGD peptide multilayers was examined in terms of the physical characteristics and in vitro blood compatibility.Results The surface water contact angle of RGD peptide self-assembly multilayer was（78.21±1.98）°,and the hemolysis rate was 0.76%.The RGD peptide self-assembly multilayer could prolong APTT to（15.1±0.2）s and effectively inhibit platelet adhesion and activation.Conclusion The blood compatibility of pure titanium can be significantly improved after being coated with RGD peptide multilayers,which are expected to become a novel biological tinanium surface and show broad application prospects in the area of medical metal surface modification.