Preparation of Optical Waveguide Devices with Polymer Nano-Assemblies for Molecular Sensing

本项目旨在研究光波导在分子传感中的应用。使用由LB膜组成的聚合物纳米组装，并结合各种光学技术，如集成光波导和表面等离子体共振技术。研究结果总结如下：1.光波导在聚合物单分子膜中的应用利用Langmuir-Blodgett(LB)技术在锥形石英波导上制备了甲基丙烯酸9-苯甲酸甲酯(AMMA)和甲基丙烯酰胺新戊酯(NPMA)共聚物的单分子膜，并用集成光波导法精确监测了该共聚物(p(NPMA-AMMA))的光谱性质。与透射式UV-Vis光谱相比，吸光度增加了200倍。因此，可以方便而准确地表征p(NPMA-AMMA)LB膜中的光交联反应随照射时间的变化。2.聚合物LB膜中正色光特性的原位观察共聚物L…制备了由N-十二烷基丙烯酰胺(DDA)和可光降解单体叔丁基-4-乙烯基苯基碳酸酯(TVPC)组成的多层B膜。在空气中，当深紫外光照射到共聚LB膜(p(DDA/tBVPC))上时，LB膜发生光解，从而使LB膜的厚度逐渐减小。另一方面，在Ar气氛中辐照，薄膜的厚度没有明显的变化。基于层间电荷转移络合物相互作用的光开关器件研究了聚合物LB膜中芘分子的荧光猝灭。使用了电子供体分子N，N-二甲基苯胺和电子受体分子1，3-二硝基苯。聚合物LB膜中的给体和受体分子通过层间电荷转移猝灭了Py的荧光。这意味着产生了新的瞬变物种。利用表面等离子体共振组态中的电荷转移反应实现了光开关。探测光强度(441.6 nm)被泵浦光(&gt；350 nm)重复调制。较少

This project aims at optical waveguide application for molecular sensing. Polymer nano-assemblies consisting of LB films was used and coupled with various optical techniques, such as integrated optical waveguide and surface plasmon resonance technique. The findings were summarized as follows;1.Optical Waveguide Application for Polymer MonolayerMonolayers from the copolymer of 9-anthrylmethyl methacrylate (AMMA) with neopentyl methacrylamide (nPMA) were deposited on a tapered quartz waveguide by Langmuir-Blodgett (LB) technique, and spectroscopic properties of the copolymer (p(nPMA-AMMA)) monolayer were precisely monitored by integrated optical waveguide technique. Magnitude of absorbance increased by a factor of 200 compared with transmission UV-Vis spectroscopy. Consequently, photo-cross-linking reaction in p(nPMA-AMMA) LB films was characterized easily and accurately as a function of irradiation time.2.In situ Observation for Positive-tone Photopatterns in Polymer LB FilmsCopolymer L … More B films composed of N-dodecylacrylamide (DDA) which is known to form a stable monolayer and a photo-degradable monomer, tert-butyl-4-vinylphenyl carbonate (tVPC), were prepared. When deep UV light was irradiated onto the copolymer LB films (p(DDA/tBVPC)) in air, the photodecomposition took place, consequently the thickness in the LB film was gradually decreased. On the other hand, there were no significant changes in the thickness with the irradiation at the argon atmosphere.3. Optical Switching Devices based on Interlayer Charge-Transfer Complex InteractionFluorescence quenching of pyrene molecules in polymer LB films was studied. An electron donor moleucule N, N-dimethylaniline and an electron acceptor molecule 1,3-dinitrobenzene were used. Pyrene fluorescence was quenched by donor and acceptor molecules in polymer LB films through inter layer charge-transfer. This implies that new transient species generate. Optical switching was demonstrated by using the charge-transfer reaction in surface plasmon resonance configuration. The probe beam intensity (at 441.6 nm) was modulated repeatedly by pumping light (>350 nm). Less