Syntheses, Properties And Application Of Fluorescent Dyes With Large Stokes Shift

Due to the simple synthesis, good biological compatibility of organic fluorescent dyes, they gradually become the vital tool to image in living cells. However, as the main physical parameter of fluorescence, stokes shift can make us design fluorescent dyes reasonably. In this paper, we designed and synthesized two types of fluorescent dyes with large stokes shift, Rhodoul and Naphthalimides, and investigated their structure, properties and applications in bioanalysis.Started with xanthene, the common parent of rhodamine and fluorescein, we embellished it with tetrahydroquinoxaline to obtain Rhodoul(RD). We modified the Rhodoul to form rhodoul methyl ester(RD-JZ), alcohol(RD-JC) and bromobenzene derivative(RD-XB). The test results of spectral properties showed that these rhodoul dyes not only emission in the near infrared region, but also have a large stokes shift(in water RD: 178 nm, RD-JZ: 130 nm, RD-JC: 130 nm, RD-XB: 150 nm). Due to the present of2,4-dinitro bromobenzene, RD-XB could recognized GSH with the presence of GST.Living cell fluorescence imaging test results showed that, three rhodoul derivatives emitted with red fluorescence in living cells. And in the presence of GST, RD-XB specificity identify GSH in living cells and glow red. The development and application of this new type of fluorescent dyes provided a broad development for cell multicolor imaging.A new fluorescent chemosensor(Lyso NO-Naph) for detecting NO in lysosomes was developed on the basis of 4-bromo-1,8-naphthalic anhydride. Spectral properties of the test results show that Lyso NO-Naph has a large stokes shift with 143 nm in acetonitrile.Lyso NO-Naph can occur with NO condensation reaction selectivity, which made the chemosensor generate blue fluorescence. Lyso NO-Naph has low detection limit of NO and can stay the same from weak acid to weak base. Moreover, through introducing a lysosome-targetable group 4-(2-aminoethyl)-morpholine into the probe, Lyso NO-Naph can recognize NO in lysosomes. The synthesis and application of this naphthalimidefluorescent probe for NO in lysosomes laid to future development.