RUI: Host/Guest Interactions of Thermochromic and Photochromic Molecules in Binary Aqueous Media

在这个项目中，惠顿学院的Maria T.Buthelezi教授和她的学生得到了化学系化学结构、动力学和机理(CSDM)计划的本科生研究活动(RUI)的支持，以研究螺吡喃与环糊精和环番的包合物的热溶变色和光致变色。除了研究这一过程的基本科学吸引力外，螺吡喃(SP，闭环形式)到花菁(MC，开环形式)的光致变色转化可用于开发开关光学应用和用于光致变色开关、光致变色透镜(验光)、荧光生物标志物、纳米温度计和药物输送装置的材料。然而，这些光和热相互转化过程是依赖于溶剂和热不稳定的，这减缓了使用该系统的应用开发的步伐。在这个项目中，我们将利用稳态光谱、纳秒时间分辨光谱、量热法和计算方法，系统地研究主体化合物的结构和溶剂组成对螺吡喃/花菁相互转化的影响。这些研究有望确定稳定螺吡喃/花菁体系的主体化合物和溶剂的组合。螺吡喃是一种光致变色和热致变色分子。在可见光下，螺吡喃(SP)溶液是无色的，但当受到紫外光照射时，溶液会变色，形成花菁(MC)。当MC溶液吸收可见光时，MC被转化回SP分子，溶液颜色消失。这种相互转化可以在某些溶剂混合物中加热来引发。像这样的转换可以用于许多重要的应用，如适应不同光线水平的眼镜和光学数字存储设备。在这些类型的应用程序中使用这种特定的转换需要彻底了解解决方案组件如何影响转换过程。Buthelezi教授和她的学生将在许多情况下研究这一过程，并使用许多方法来努力发展这种理解。惠顿学院的本科生将参与这个项目的所有方面，从拟议的项目中获得的实践经验将对他们的职业前景产生重大影响，并为他们继续研究生或健康专业学习以及最终在学术界、政府实验室和行业就业做好准备。

In this project, Prof. Maria T. Buthelezi and her students at Wheaton College receive support under the auspices of the Research in Undergraduate Institutions (RUI) activity from the Chemical Structure, Dynamics and Mechanism (CSDM) program of the Division of Chemistry to investigate the thermosolvatochromism and photochromism of spiropyran inclusion complexes with cyclodextrins and cyclophanes. In addition to the fundamental scientific appeal of studying this process, photochromic conversion of spiropyran (SP, closed ring form) to merocyanine (MC, open ring form) may be used in the development of on-and-off optical switching applications and materials for photochromic switches, photochromic lenses (optometry), fluorescent biomarkers, nanothermometers, and drug delivery devices. However, these photo- and thermal-interconversion processes are solvent dependent and thermally unstable, which have slowed the pace of application development using this system. In this project, systematic investigation of the impact of host compound structure and solvent composition on spiropyran/merocyanine interconversion will be investigated using steady-state optical spectroscopy, nanosecond time-resolved optical spectroscopy, calorimetry and computational methods. These studies are expected to identify combinations of host compound and solvent that stabilize the spiropyran/merocyanine system. Spiropyran is a photochromic and thermochromic molecule. Under visible light, spiropyran (SP) solutions are colorless, but when subjected to ultraviolet light, the solutions become colored as merocyanine (MC) is formed. When MC solutions absorb visible light, MC is converted back to SP molecule and the solution color disappears. This interconversion can be initiated with heat in some solvent mixtures. Conversions like this can be used in many important applications such as eyeglasses that adapt to varying light levels and optical digital storage devices. Utilizing this specific conversion in these kinds of applications requires a thorough understanding of how the solution components affect the conversion process. Prof. Buthelezi and her students will investigate this process under many conditions and using many methods in an effort to develop that understanding. The undergraduate students at Wheaton College will be involved in all aspects of this project and the hands-on experience gained from the proposed project will impact significantly their professional outlook and prepare them to pursue graduate or health professional studies and for eventual employment in academia, government laboratories, and industry.