A wavelength-tunable and facilely functionable D-A type naphthalene core skeleton: Synthesis, photophysical property, and bio-imaging applications for cells and tissues

Abstract

A new wavelength-tunable and facilely functionable electron donor (D)-acceptor (A) type fluorescent naphthalene core skeleton and its application for cell membrane imaging are reported. The core skeleton shows bright green fluorescence with aldehyde(-CHO) moiety at the electron acceptor site, and its emission wavelength is tuned to blue and red by introducing the moiety of nitrile (-CN) and dicyanovinyl (-CH(CN)2), respectively, at the acceptor site. In addition, the core skeleton can be readily functionable by introducing a targeting moiety at the extra hydroxyl group. For the first demonstration as a fluorescent probe, a long-chain carbon is introduced and evaluated its bio-imaging ability for the cellular membranes on cells and tissues by using confocal laser scanning microscopy (CLSM) and two-photon microscopy (TPM). The synthesis, photophysical property, and quantum chemical calculations are also identified.