The Design, Synthesis And Characterizations Of Large Stokes Shift Dyes, Novel Photo-triggered NO Donors And Fluorescence

Fluorescence based techniques have become indispensable since 1980s. Traditional fluorescenct dyes such as fluorescein, rhodamines, coumarins, BODIPYs, and cyanine dyes have found wide-spread applications. Recently, the development of fluorescence based techniques have imposed higher requirements toward fluorescent dyes and this brings novel growth points for the field of synthetic dye chemistry. In flowcytometry, it has become routine practice to use two or more dyes simultaneously for multiplexing purposes. This allows extraction of two or more fold of information via different spectral channels. To quality for such applications, the pair of dyes should exhibit common excitation wavelength, but well-separated emission wavelengths to avoid mutual-interferences. Fluorescein and R-phycoerythrin are such a pair of dyes. However, due to the fact that R-phycoerythrin is a large fluorescent protein of ca.160 KD, its use in many other applications was limited. We have developed a series of novel fluorescent dyes, aminobenzo[c]cinnolinium dyes to replace R-phycoerythrin in such applications.Nitric oxide is an important endogenous small signaling molecule and play versitle roles in numerous physiological and pathological processes. However, the mechanism of NO involvement in many processes is not clearly understood. In these studies, nitric oxide donors are routinely used as a positive control. However, biological responses from the addition of such NO donors are not readily studied due to the fact that these spontaneous NO donors do not release NO in a controlled fashion. We have developed a class of NO donors to address this difficulty. Such NO donors will release NO upon UV irradiation and will give a fluorescence turn-on as well for convenient monitoring of the localization and kinetics of NO release.Hypochlorite is an important endogenous reactive oxygen species. Low level of hypochlorite is physiological and high level is pathological. Development of high-performance hypochlorite fluorescent probe is highly anticipated for in vitro or in vivo studies. We have designed and synthesized a novel fluorescent probe for hypochlorite based on our "covalent assembly" principle. The spectral and biological studies are ongoing.