A highly selective and sensitive 1,8-naphthalimide-based fluorescent sensor for Zn2+ imaging in living cells

•1,8-Naphthalimide-based fluorescent Zn2+ sensor with a new receptor contained two different arms iminoacetic acid and iminoethoxyacetic acid, was synthesized.•It demonstrates high selectivity and sensitivity for sensing Zn2+.•It was applied successfully to detection of Zn2+ in aqueous solution and image Zn2+ in living cells.