LIFETIME STUDY OF FLUORESCENT POLYMER SENSORS

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 我们一直在研究一系列含有多受体组件的新型荧光共轭聚合物材料。多个受体位置通过共轭聚合物(分子线)电子连接，并显示出比更传统的基于分子的荧光化学传感器更大的灵敏度增益。这些聚合物已被发现在低至4×10-9M的浓度下对过渡金属离子做出定量响应。我们还开发了一种新的方法来创建无机/有机杂化聚合物，通过“开启”荧光机制做出响应。该混合体系在生物铁的选择性检测中显示出良好的效果。为了更全面地描述荧光猝灭过程的动力学，有必要进行时间分辨发射和瞬时吸收测量。鉴于这些聚合物的非线性Stern-Volmer行为，这一点尤其重要，这些行为可归因于聚合物主链上的能量传递动力学和更传统的静态猝灭的组合。一个特定的光物理目标将是确定在猝灭过程中是否形成电荷转移产物。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. We have been investigating a new series of fluorescent, conjugated polymer materials that contain polyreceptor assemblies. The multiple receptor sites are electronically connected by the conjugated polymer (molecular wire) and exhibit larg sensitivity gains over more conventional molecule-based fluorescent chemosensors. These polymers have been found to respond quantitatively to transition metal ions at concentrations as low as 4*10-9 M. We have also developed a new method to create inorganic/organic hybrid polymers that respond through a "turn-on" fluorescence mechanism. This hybrid system is showing promising results for the selective detection of biological iron. In order to more completely characterize the dynamics of the fluorescent quenching process, time-resolved emission and transient absorption measurements are necessary. This is particularly important in light of the non-linear Stern-Volmer behavior of these polymers that can be attributed to a combination of energy transfer dynamics on the polymer backbone and more traditional static quenching. A specific photophysical goal will be to identify whether charge transfer products are formed during the quenching process.