DNA 하이드로겔 기반의 다공성 구조를 갖는 전도성 하이브리드 섬유의 제조 및 특성 연구

Abstract

ABSTRACT

Synthesis and Characterization of Highly Responsive Fiber by Porous Structure composed DNA

Lee, Sun Hee Dept. of Biomedical engineering The Graduate School Hanyang University

Exploring porous structured materials have been interested to actuator, bio-sensor to function as excellent electrochemical properties by high surface area for detection, energy storage, and ion transport channel. DNA hydrogels have been shown fast and large length in change to stimulus by salt and pH. This response by DNA arises from the electrostatic repulsion of the phosphate groups of DNA and from the hydrophobic interaction of the base pairs of the flexible DNA backbone. Furthermore, DNA hydrogel fiber have porous structure giving high surface area. The DNA hydrogel fibers we developed were shaped into fibers through a randomly intertwined and entangled network of individual DNA strands without any chemical modification. This means that the response of these DNA hydrogel fibers to pH and salt reflected the conformational changes of a single DNA strand. Surprisingly, the DNA hydrogel fibers show a fast and large change in length to a salt and pH stimulus under biological conditions ([Na+] = 0.15 M at pH = 7), and these DNA hydrogel fibers may be useful in bio-artificial muscles. And then using the DNA high porous structure, we successfully achieved the stable and improved actuation performance of PPy/CNT hybrid fiber although DNA/PPy/CNT hybrid fiber have not good conductivity. It means that high surface area is very important for actuation performance. The high performing DNA/PPy/CNT hybrid fibers have been prepared by a simple chemical polymerization. The porous structure of DNA hydrogel fibers induced uniformly doped the PPy on inner and outer surface through the association of PPy on DNA with supramolecular interaction. As a result, the Porous structure of DNA/PPy/CNT hybrid fibers caused that the ion can easily go in out on the surface. Therefore DNA/PPy/CNT hybrid fibers have the enhanced actuation performance without gradation from outer surface to inner surface in a low electrolyte concentration and at the low applied voltage. Additionally, DNA/PPy/CNT hybrid fibers also have improved capacitance. Therefore DNA/PPy/CNT hybrid fibers will form the basis for new intelligent materials for applications, such as artificial muscles.