The Synthesis and Spectral Properties of Some New Monomethine Cyanine Dyes for Live Cell Imaging

Abstract

Four monomethine cyanine dyes were synthesized and their structures were confirmed by 1H NMR, IR, UV–Vis, and HRMS. Their spectral properties were studied. It could be found that the λmax of the dyes was shorter in the protonic solvents compared with that in the non‐protonic solvents. Moreover, the λmax shows a hypsochromic shift with the increasing polarity of the solvents. The interactions of four dyes with DNA were also studied. The results showed that the fluorescence intensities of the dyes 3a and 3b took place a qualitative change in the presence of DNA compared with the free dyes. The dyes used as cellular imaging agents were researched. The results indicated that the dye 3b could penetrate the live cell membrane.