Effect of Hydration on Interfacial Interactions between DNA Brush Layers

2017 Fiscal Year Final Research Report

• Project/Area Number: 26410232
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Polymer/Textile materials
• Research Institution: Shinshu University (2016-2017); Institute of Physical and Chemical Research (2014-2015)
• Principal Investigator: KANAYAMA Naoki 信州大学, 総合工学系研究科, 准教授(特定雇用) (80377811)
• Project Period (FY): 2014-04-01 – 2018-03-31
• Keywords: DNA / 界面 / 水和 / 界面間力 / フォースカーブ

Outline of Final Research Achievements

Colloidal probe atomic force microscopy was employed to examine how the outermost base pairs affect the interaction between the dsDNA-grafted layers (dsDNA layers). The dsDNA layers having complementary (GC) or mismatched (CC) outermost base pairs were grafted onto the surfaces of colloidal probes and gold substrates. Force-distance curves measured in an aqueous medium under high-salt conditions revealed that the surface forces between the dsDNA layers were bilateral in nature and were governed by the outermost base pairs. Between complementary outermost dsDNA layers, the surface force changed from repulsive to attractive with an increase in the NaCl concentration (10-1000 mM). The attraction observed under high-salt conditions was attributed to the site-specific interaction proceeded only between complementary dsDNA terminals. In fact, between mismatched outermost dsDNA layers, the repulsive force was mostly dominant within the same NaCl concentration range.

Free Research Field

生体関連高分子