血浆蛋白分子在单壁碳纳米管无纺膜表面吸附行为的研究

近年来,碳纳米管的独特表面拓扑结构、化学组成和优异的物理性能已经吸引了众多领域的研究兴趣,以生物医学应用为目标的探索性研究正在迅速形成一个新的方向。我们以血液接触环境下的应用为目标,通过扫描电镜观察、表面元素分析、以及利用酶联免疫分析技术,系统研究了与凝血过程密切相关的纤维蛋白原、白蛋白、免疫球蛋白以及新鲜血浆在单壁碳纳米管无纺膜(SWNT膜)表面的吸附行为。实验结果显示,单壁碳纳米管无纺膜对血浆中的纤维蛋白原分子具有强烈的倾向性吸附,对免疫球蛋白也显示出一定的吸附性,但是,对白蛋白分子却几乎不吸附。血浆蛋白分子在SWNT膜表面的吸附行为与其在其它碳材料表面和其它大多数生物材料表面的吸附行为显著不同。SWNT膜对血浆蛋白分子的独特吸附作用有可能对后续的血液细胞响应产生重要影响。

Study of the Adsorption Behaviors of Plasma Proteins on the Single-walled Carbon Nanotubes Nonwoven

Single walled carbon nanotubes (SWNT) have attracted increasing research interests for the purpose of biomedical application because they provide not only nanostructured topography, but also chemical composition of pure carbon atoms, as well as ultra high strength and excellent flexibility. Regarding the interactions of nanomaterials to biological systems, non-specific adsorption of plasma proteins is one of the most important issues to be concerned, which plays a crucial role that would determine how biological systems response to the biomaterials. Motivated by application of SWNT materials in biomedical fields, in this study, the adsorption behaviors of plasma proteins on the surface of SWNT nonwoven, prepared directly by floating chemical vapor observation and energy deposition method were investigated by means of scanning electron microscope (SEM), dispersive X-ray (EDX) analysis and ELISA. Results indicated the SWNT non-woven showed a clear adsorption preference of fibrinogen over albumin. There was no human serum albumin detected using above analysis methods on the SWNT nonwoven even incubated in the albumin solution of 4 mg/ml. While more than 0.15 microg of human fibrinogen was detected by ELISA on the SWNT nonwoven with area of 40 mm x 40 mm incubated in the fibrinogen solution of 5 microg/ml. In addition, IgG of sheep-anti-human serum fibrinogen exhibited strong nonspecific adsorption on the surface of SWNT nonwoven. The adsorption behaviors are different significantly from those of other carbon materials and conventional biomaterials. The unique interaction of SWNT nonwoven to plasma proteins is of significance to further studies of blood cells responses.