新型近红外试剂的合成及其现场二聚体与DNA作用的研究

合成了一种新型近红外阴离子染料，并对其水溶液及阳离子表面活性剂ＣＴＡＢ存在下的吸收荧光光谱进行了研究。结果表明，低浓度的ＣＴＡＢ与该近红外阴离子染料形成离子缔合物而使阴离子染料的荧光强度降低，当ＣＴＡＢ的浓度进一步加大时，其胶束前预聚集促使该染料形成非荧光二聚体，导致荧光急剧猝灭。

Synthesis of a Novel Near-IR Fluorescent Reagent and Study on its in-situ Dimer's Interaction with DNA

A new anionic Near IR fluorescent cyanine dye was synthesized and its absorption and fluorescence spectra in water and in the solution of cationic surfacant hexadecyltrimethyl ammonium bromide(CTAB) were studied. The results showed that the maximum excitation wavelength and emission wavelength were 765 nm and 795 nm in water, respectively. In the presence of low concentration of CTAB, the dye formed ionic associate with CTAB was made higher to form the premiceller aggregation, the fluorescence intensity decreased dramatically because of forming a low fluorescent in situ dimeric dye. When the concentration of CTAB was above the critical micelle concentration(cmc), the dimeric dye dissociated, and the fluorescence intensity of Near IR cyanine was restored, and the maximum emission wavelength was bathochromated from 795 nm to 812 nm. The possibility of using low fluorescent in situ dimeric dye as a Near IR region fluorescent probe for DNA was also studied.