Development of high performance photoelastic modulator and its application to measurements of solid-state circular dichroism

高性能光弹调制器的研制及其在固态圆二色性测量中的应用

基本信息

批准号：
15550011
负责人：
MAEDA Shiro
金额：
$ 1.6万
依托单位：
University of Fukui
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2003
资助国家：
日本
起止时间：
2003 至 2004
项目状态：
已结题

项目摘要

(1)Improvement of photoelastic modulator (PEM) driverPEM driver, which is optimized to have highest driving efficiency by means of phase-locked loop technique, was improved to have a wide range of driving frequency.(2)Development of thin PEM headsNovel thin PEM heads were made to minimize residual birefringence in the optical element of PEM head which results in artifact signals in solid-state CD measurements. The thickness of the conventional PEM head had been 6.4 mm from the birth of Schnattery type PEM. The thicknesses of novel PEM heads are 2, 3, and 4 mm. The values of R in the electrical equivalent circuit of PEM head are quite low compared with conventional ones.(3)In situ measurement of CD of DNA adsorbing onto a solid surfaceThe adsorption process of DNA dissolved in aqueous solutions onto the surface of polyethyleneimine (PEI) has been examined by the observation of in situ CD, including time-resolved measurements, to elucidate the conformation of DNA at the liquid/solid interface. The adsorption process can be characterized by two stages that are characterized in terms of CD. In the first stage, time (t) <700s, a slight change in the time-resolved CD spectra of DNA is observed, whereas in the second stage, t>700s, where no further adsorption occurs, a change in the induced CD as well as in the CD of DNA is observed.(4)Structural investigation of Poly(ε-lysine) (PL)by solid state-CD measurements.The conformation of microbial PL was estimated by means of solid-state CD measurements. The CD measurements were done by using artifact-free technique for the PL films obtained by casting the aqueous solution with various pH onto a glass plate.

（1）改进光弹性调制器（PEM）驱动程序驱动程序，该驱动器驱动器通过相锁定的环路技术进行了优化，其驱动效率最高，以提高到具有广泛驱动频率的范围。（2）制造薄PEM头的发展新型PEM头部，以最大程度地减少PEM头部光学元件中的残留双折射，从而导致固态CD测量中的伪影信号。传统PEM头的厚度与Schnattery型PEM的诞生相距6.4毫米。新型PEM头的厚度为2、3和4毫米。与常规电路相比，PEM头部电路中R的值非常低。（3）原位测量DNA的Cd的DNA cd上吸附到溶解在水溶液中的固体表面表面吸附过程中，包括在溶解在多乙烯（PEI）上的水溶液表面上，包括对cd的量子的测量，包括时间，对cd进行了测量。液体/实心界面。添加吸附过程可以以CD为特征的两个阶段来表征。在第一阶段，时间（t）<700s，观察到时间分辨的DNA的CD光谱发生了略有变化，而在第二阶段，在第二阶段，t> 700s，没有进一步添加吸附，诱导的CD的变化以及DNA的CD中的CD和CD的变化。通过固态CD的测量，CD测量是通过使用无伪影技术来完成通过将各种pH的水溶液施放到玻璃板上获得的PL膜的。