作者：Fang CHENG1,2, Mingyang LI1,2, Wei HE1,3, Hanqi WANG1,2
1 State Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian 116023, Liaoning Province, P. R. China
2 School of Pharmaceutical Science and Technology, Dalian University of Technology, Dalian 116023, Liaoning Province, P. R. China
3 School of Chemical Engineering, Dalian University of Technology, Dalian 116023, Liaoning Province, P. R. China
摘要：Control over the ligand surface density provides an accurate molecular basis for the quantitative study of biomolecular interactions. However, the classic hybrid self-assembly method lacks general applicability toward different self-assembly systems. In this paper, we report a new method based on the reaction kinetics of vinyl sulfone groups presented on surface to control the surface ligand density. Nα, Nα-bis(carboxymethyl)-L-lysine (ab-NTA) was selected as the model biological ligand and the catalyst for surface reaction was screened. The surface reaction was characterized by X-ray photoelectron spectroscopy (XPS) and the surface membrane potential. Static water contact angle was used to quantify the kinetics of the surface reaction, and calculations showed that the rate constant was 0.0012 min-1. The ability of the biological functional surface to bind a histidine labeling protein (SA-6His) was investigated by surface plasmon resonance (SPR). The results show that such a surface has a higher protein binding quantity and binding strength than the traditional NHS-NTA surface. Four biological functional surfaces with different ligand densities were prepared by controlling the reaction time and catalyst, and the protein static adsorption of these surfaces was analyzed by SPR. The results show that ligand density and multivalence of the biological functional surface can be controlled by modulating the reaction time and catalyst.
