화학공학소재연구정보센터
Langmuir, Vol.31, No.15, 4386-4393, 2015
Highly Emissive Nanoparticles Based on AIE-Active Molecule and PAMAM Dendritic "Molecular Glue"
The highly emissive nanoparticles Gn-TCMPE (n = 0-4) were prepared by using PAMAM dendrimers as "molecular glue" to adhere an AIE-active molecule tetra(4-(carboxymethoxy)phenyl)ethylene (TCMPE). The electrostatic interaction of ammonium carboxylate ion pairs provides a driving force between TCMPE and PAMAM dendrimers to form the nanoparticles Gn-TCMPE (n = 0-4), which is validated by the FTIR and H-1 NMR spectra. The formation of nanoparticles dramatically blocks the nonradiative pathway and enhances the fluorescence of TCMPE. The quantum yields of Gn-TCMPE gradually boost at first and then reach to a plateau with increasing the generation of PAMAM dendrimers, and the highest absolute quantum yields are obtained to be 0.42 and 0.64 for Gn-TCMPE (n = 2 4) in methanol dispersion and solid phases, respectively. The fluorescence of the nanoparticles can be tuned by addition of ttifluoroacetic acid (TEA). Furthermore, the G4-TCMPE has been successfully applied to selectively image cytoplasm of Hela Cells with excellent photostability and low cytotoxicity. This study provides a novel noncovalent strategy for developing highly emissive and robust organic materials fitting for cell fluorescence imaging.