Department of Bioengineering, The University of Tokyo, 1-3-7 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.
Institute of Engineering Innovations, The University of Tokyo, 1-3-7 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.
Colloids Surf B Biointerfaces. 2015 Jun 1;130:119-25. doi: 10.1016/j.colsurfb.2015.04.024. Epub 2015 Apr 18.
The effect of hydroxyl radicals (OH) and thermal annealing on an amorphous InGaZnO4 (aIGZO) film surface was investigated for manipulation of DNA immobilization. X-ray photoemission and fluorescence measurements were conducted to reveal the status of surface OH coverage and DNA immobilization, respectively. Systematic examinations concerning OH termination on the film surface suggested that the surface coverage of OH leveling DNA immobilization was related to the local surface potential. Furthermore, OH affinity on the aIGZO film surface was sensitive to thermal annealing. A remarkable change in surface OH coverage was observed for the film surface annealed at high temperature. This behavior was framed by a structural change from amorphous to crystalline state, which regulated DNA immobilization. These results indicate that the OH affinity on aIGZO films is dependent on structural properties such as defects. This study suggests that an amorphous structure is critical for obtaining a high OH surface coverage governing DNA immobilization, and is hence more suitable for biosensing.
研究了羟基自由基 (OH) 和热退火对非晶 InGaZnO4 (aIGZO) 薄膜表面的影响，以实现 DNA 固定化的操控。分别通过 X 射线光电子能谱和荧光测量来揭示表面 OH 覆盖度和 DNA 固定化的状态。关于薄膜表面 OH 终止的系统研究表明，表面 OH 覆盖度与局部表面电势有关。此外，aIGZO 薄膜表面对 OH 的亲和力对热退火很敏感。对于在高温下退火的薄膜表面，观察到表面 OH 覆盖率的显著变化。这种行为是由非晶态到晶态的结构变化所决定的，从而调节了 DNA 的固定化。这些结果表明，aIGZO 薄膜表面的 OH 亲和力取决于结构特性，如缺陷。本研究表明，获得控制 DNA 固定化的高 OH 表面覆盖率，非晶结构是至关重要的，因此更适合用于生物传感。
