Chemical and biological processes studied with advanced imaging techniques

我们的研究计划集中在开发基于荧光的方法来研究化学和生物系统，以及应用使用这些方法获得的基本知识来产生新的材料和诊断。我们能够合成具有理想的化学反应性和光物理行为的定制荧光探针，然后开发和利用最先进的单分子荧光成像方法，以追求复杂系统的机械基础。 我们研究工作的基础是我们监测单分子活动的能力。单分子光谱学领域已经从最初专注于生物物理现象的研究，发展到对非均相介质中反应的机械探索，包括表面和各种纳米复合材料/催化剂。最诱人的是最近在生物系统成像和催化剂表征方面取得的突破，这些催化剂具有“超分辨率”(超出衍射极限)和灵敏度。这些技术利用对化学反应(含氟化合物)的荧光诱导/增强来可视化、绘制地图并最终理解在微观和纳米(十亿分之一米)水平上发生的事情。然而，这些技术主要局限于光化学触发的荧光探针的子集(它们是物理观察者-信标)。在仔细设计对感兴趣的活性化学物种(活跃的参与者“化学耀斑”)作出反应的含氟化合物的基础上，存在着询问生物系统和纳米材料的巨大机会。 在即将到来的赠款期间，我们将利用我们过去6年的进展和超分辨率成像领域的最新发展，致力于解决三个相互关联的当代问题。(I)我们将设计和制备荧光探针，以监测脂膜的氧化还原状态，并设计和制备荧光亲电探针，以触发类似于观察到的脂质过氧化副产物的反应。我们的目标是建立活性氧物种(ROS)的化学与其生物学之间的关系。(Ii)我们将实施我们新开发的探测器，结合短信息技术和超分辨率成像战略，可视化、绘制和研究生物系统和纳米材料中的关键氧化还原过程。(Iii)我们将开发新的SMS策略，探索超分子结构/纳米材料的结构和组装动力学，并调整条件，以获得高产量和更高质量的材料。在这种情况下，我们的目标是获得关键的机械信息，并在适用的情况下将其转化为更好的纳米材料的制造。 总的来说，我们将获得关于新化合物的光化学/光物理的知识。我们将开发具有许多研究人员寻求的功能的分子。化学选择性探针和成像方法将使与ROS产生相关的细胞功能和活动产生广泛影响的根本性转变发现成为可能。这些探针和成像方法也将为制备改进的纳米材料/超分子结构铺平道路。待开发的新成像技术将成为纳米科学质量和结构表征的标准。 我们的计划将提供里程碑式的例子，探索独特的方法，并开发尖端成像技术来了解化学和生物系统。

Our research program centres on the development of fluorescence-based methodologies to study chemical and biological systems, and on the application of the fundamental knowledge gained using these methods to generate novel materials and diagnostics. We are able to synthesize customized fluorescent probes with desirable chemical reactivity and photophysical behaviour, and to then develop and exploit state-of-the-art single molecule fluorescence imaging methodologies with them, in our pursuit of the mechanistic underpinning of complex systems. Fundamental to our research work is our ability to monitor single molecules in action. The field of single molecule spectroscopy has evolved from its original focus on the study of biophysical phenomena, to mechanistic exploration of reactions in heterogeneous media, both on the surface and within a diverse range of nanocomposite materials/catalysts. Most tantalizing are recent breakthroughs in the imaging of biological systems and characterization of catalysts at work with “super resolution” (beyond diffraction limit) and sensitivity. These techniques exploit the induction/enhancement of fluorescence upon a chemical reaction (fluorogenic compounds) to visualize, map and ultimately understand what occurs at the microscopic and nanoscopic (a billionth of a meter) level. The techniques are however mostly limited to a subset of fluorogenic probes that are photochemically triggered (they are physical spectators - beacons). Tremendous opportunities exist to interrogate biological systems and nanomaterials upon careful design of fluorogenic compounds that respond to reactive chemical species of interest (active players “chemical flares”). In the coming grant period we will capitalize on our progress of the past 6 years and on recent developments in the field of super resolution imaging working on 3 interrelated contemporary problems. (I) We will design and prepare fluorogenic probes to monitor the redox status of lipid membranes and also fluorogenic electrophilic probes to trigger reactions akin to those observed with by-products of lipid peroxidation. Our goal is to establish the relationship between the chemistry of reactive oxygen species (ROS) and their biology. (II) We will visualize, map and study key redox processes both in biological systems and nanomaterials implementing our newly developed probes, combining SMS and incorporating super resolution imaging strategies. (III) We will develop new SMS strategies to explore the structure and the assembly dynamics of supramolecular structures/nanomaterials tuning conditions for high yields and improved quality materials. Our goal in this case is to gain key mechanistic information and translate it to the manufacture of better nanomaterials when applicable. In general, we will gain knowledge on the photochemistry/photophysics of new compounds. We will develop molecules that have functions that many researchers seek. The chemoselective probes and imaging methodologies will enable fundamental transforming discoveries of broad impact on cell function and activity correlated with ROS production. The probes and imaging methods will also pave the way to prepare improved nanomaterials/supramolecular structures. New imaging technologies to be developed will become the standards of quality and structural characterization in nanoscience. Our program will provide landmark examples where unique approaches are explored and cutting-edge imaging technologies are developed toward understanding chemical and biological systems.