碳纳米管复合微球修饰L-色氨酸及其对LDL的吸附性能

本文以多孔碳纳米管/活性炭复合微球为载体, 以L-色氨酸为配基, 采用环氧氯丙烷偶联法, 制得修饰L-色氨酸的碳纳米管/活性炭复合微球(L-CNTs/AC)。采用扫描电镜、氮气吸附、傅立叶红外光谱、热分析、X射线光电子能谱等对复合微球进行表征;通过体外静态吸附法对其低密度脂蛋白(LDL)吸附能力进行初步研究。结果表明:环氧氯丙烷偶联法可接枝上L-色氨酸。复合微球中碳纳米管加入量越多, 对LDL的吸附能力越强;当碳纳米管加入量为45wt%时, 对LDL的吸附量达4.623 mg·g^-1, 是未添加碳纳米管的2.3倍多。这是因为碳纳米管不仅可促进复合微球中20~100 nm孔的形成, 而且还可促进复合微球配基修饰量的增多, 从而大大增强了复合微球对LDL的吸附能力。此复合微球可望开发成一种新型的血液灌流LDL吸附剂。

Modification Carbon Nanotubes Composite Beads by L-Tryptophan and Their Adsorption Capacity for Low Density Lipoprotein

The porous carbon nanotubes (CNTs)/activated carbon composite beads were modified by L-tryptophan using epichlorohydrin coupling method. The composite beads were characterized by SEM, N2 adsorption, FTIR, TGA and XPS etc. Then these composite beads were applied to adsorb low density lipoprotein (LDL) by static adsorption experiment in vitro. The results show that the composite beads could be modified by L-tryptophan using epichlorohydrin coupling method. With the increase CNTs mass ratio, the adsorption capacity of LDL increase. When CNTs ratio is 45wt%, the adsorption amount of LDL reaches 4.623 mg·g^-1, is 2.3 times as great as that of beads without CNTs. These should be ascribed to the highly developed 20~100 nm porous structures and the increase of L-tryptophan amount on the composite beads mainly brought about by CNTs, enhancing the LDL adsorption ability onto the composite beads greatly. So the composite beads have good prospects as LDL adsorbent in hemoperfusion.