Diarylene Fluorescent Switches And Their Biological Applications

Diarylethene is one of the most promising photoswitchable units within the classic photochromic system because of its excellent thermal stability, great fatigue resistance, fast response and high quantum yield. But now research of this kind material is mostly localized in organic field. Thus, the research work on exploiting the applications in biomaterials is carried out. A series of diarylethene have been designed and synthesized by improving fluorescence and water-dispersibility. The characteristic of structures and spectra by light regulating and the applications in fluorescence imaging and photo delivery were studied.1. Amphiphilic Diarylethene for Cells ImagingAmphiphilic molecules were designed with hydrophilic and hydrophobic chains at two ends of a rigid diarylethene core. Because of the self-assembly by hydrophobic force, they formed stable vesicles in water and exhibits obviously different fluorescence and color in open and closed states under alternating irradiation of UV and visible light. These fluorescence probes had potential utility as cellular markers or fluorescence switches with high-ratio signal change, excellent resistance to fatigue, low cytotoxicity and great biocompatibility.2. Targeted Diarylethene for Metal Ions SensorTargeted diarylethene was designed with terpyridine functional units. It exhibited effective switchable fluorescence controlled by UV/visible light or metal ions/EDTA in solution, because of the photochromic reaction and coordinating with Zn2+ and Cu2+. It also had potential application as imaging and metal ions sensor. It served well as a photoswitchable probe for cell imaging with low cytotoxicity, acted as a detector for the biological process of the metal ion transmembrane transport.3. Nano Hybrid Diarylethene Materials for Photo-control drug delivery modelNano hybrid materials were designed with the substance of silica nanoparticles and the luminescence features of UCNPs, combined with synthesized fluorescent naphthalic anhydride and fluorescence switch of diarylethene by the linkage of photo sensitizer of nitrobenzyl, which was served as research model for photo-control drug delivery. It released the fluorescence group by light stimulus in solution, simulated drug delivery in organism by cell imaging.