Steady State and Lifetime Fluorescence Spectrophotometer

麻省理工学院化学工程系打算购买一台SPEX Fluorolog-T2荧光光谱仪，该仪器将专门用于支持工程研究。该仪器将用于环境、生物和材料领域的几个研究项目，以探测不同微域提供的微环境，这些系统包括：(I)嵌段共聚胶束和树枝状星形聚合物，用作分离和反应的增溶介质；(Ii)用于色谱和传感器的量身定制的自组装有机表面；(Iii)用于药物合成反应的新型溶剂，包括超临界流体介质；(Iv)用于光催化的胶体纳米晶体；(V)经过化学修饰的荧光；以及(Vi)与聚合物相连的蛋白质，作为细胞表面受体的配体。使用稳态和时间分辨的荧光和去极化可以获得有关微极性、宏观粘度、对探针旋转和过渡运动的限制以及特定和非特定溶剂化效应的信息。不同微域(如胶束、薄膜、蛋白质活性链、无机吸附体)之间的探针交换动力学将被量化，并确定微域的大小，如胶束。这些结果将对所考虑的应用范围内的微多相系统的设计有所帮助。

ABSTRACT T. Alan Hatton MIT CTS-9500227 The Department of Chemical Engineering at the Massachusetts Institute of Technology intends to purchase a SPEX Fluorolog-t2 Fluorescence Spectrometer which will be dedicated to support research in engineering. This instrument will be used for several research projects in the environmental, biological and materials areas to probe the microenvironments afforded by different microdomains in systems such as: (i) Block copolymer micelles and dendritic star polymers to be used as solubilization media for separations and reactions; (ii) tailored self-assembled organic surfaces for chromatographic and sensor applications; (iii) novel solvents for pharmaceutical synthesis reactions, including supercritical fluid media; (iv) colloidal nanocrystals for photocatalytic applications; (v) chemically-modified fluoresces; and (vi) proteins tethered to polymers as ligands for cell-surface receptors. Information on micropolarities, mocroviscosities, restrictions on rotational and transitional motion of probes, and specific and non-specific solvation effects can be obtained using steady state and time-resolved fluorescence and depolarization. Dynamics of exchange of probes between different microdomins (e.g., micelles, thin films, protein active sties, inorganic adsorbates) will be quantified, and the sizes of microdomains such as micelles determined. These results will be useful in the design of microheterogeneous systems for the range of application considered.