Development of Nonoactuators by Using of Light Radiation Pressure

本研究在阐明DNA链凝聚态物理的同时，开发了利用DNA链的纳米致动器1。要使DNA链以辐射力为驱动力进行扩张和收缩，首先需要在DNA链末端结合一个固定在金薄膜（衬底）上的金纳米胶体粒子。对于金胶体或金膜与DNA链的结合，分别采用DNA末端的生物素与金胶体上的链亲和胺之间的抗原抗体反应或DNA另一端的金（底物）与巯基之间的结合反应。利用Nd:YAG激光器和光学显微镜组成的光学操作设备，研制了DNA柔性操作系统。利用该系统在水溶液中对λ DNA进行操纵操作时，发现利用光对DNA分子进行捕获和移动操作是可能的。为了探测光控制金薄膜基片-金胶体之间距离的表面等离子体共振信号，研制了以氦氖激光为光源的表面等离子体共振测量系统。在SPR测量中，单链和双链DNA的SPR信号出现了显著差异。根据链式条件的不同，DNA分子的物理性质（长度和弹性）不同。通过重复上述第1节中描述的方法，可以制备可控的多个dna -金胶体层。随着层数的增加，SPR信号有显著的正角位移，且随层数的增加，SPR信号增强。因此，SPR信号的增强表明dna -金胶体层的增殖。这项研究表明，DNA分子作为纳米致动器材料是很有前途的。

In this research, while clarifying the condensed matter physics of a DNA chain, nanoactuators using the DNA chain were developed1.To make a DNA chain expand and contract by radiation forces as driving forces, it is necessary to bind a gold nano-colloid particle at the end of the DNA chain fixed on gold thin film (substrate) first of all. For binding between either the gold colloid or the gold film and the DNA chain, antigen-antibody reaction between biotin at the end of the DNA and streptavidine on the Au colloid or binding reaction between gold (substrate) and thiol group at the another end of the DNA was used, respectively.2.The DNA flexible operation system using the optical manipulation equipment which consists of Nd:YAG laser and an optical microscope was developed. When manipulation operation of λ DNA was preformed in aqueous solution using this system, it found out that capture and movement operation of the DNA molecule were possible using light.3.To detect the surface plasmon resonance (SPR) signals in controlling the distance between gold thin film substrate-gold colloid by light, the SPR measurement system wish He-Ne laser as a light source was developed. In the SPR measurement, remarkable difference in the SPR signal between the single-and double-strand DNA appeared. It is suggested that the difference arises in the physical properties (length and elasticity) of the DNA molecule according to a chain condition.4.By repeating of the method described in the section I above, controllable multiple the DNA-gold colloid layers can be fabricated. Remarkable positive SPR angular shift was observed with increase of the layer numbers, and enhancement of the SPR signal accompanying multilayering was shown. Therefore, the enhancement of the SPR signal suggests that the multiplication of the DNA-gold colloid layer. This research has shown that DNA molecules were promising as nanoactuator materials.