Abstract: The development of water-soluble fluorescent probes has become a topical research area for environmental and biological applications. Water solubility is desired for fluorescent probes to function in aqueous media. The introduction of water-soluble groups to conventional organic fluorophores is challenging in terms of preparation and purification. In this paper, fluorescent probes 3 , 6 and 9 based on spirobilfuorene skeleton were designed and synthesized, featuring naphthalene anhydride functionality. These compounds were prepared by hydrolysis of corresponding molecules bearing naphthalenedimide, which is a common electron acceptor often used in fluorophores. The anhydride group not only allows these compounds to be separated and purified in common organic solvents, such as chloroform and tetrahydrofuran, but also imparts enough water solubility. The anhydride group undergoes hydrolysis upon exposing to alkaline conditions in aqueous media, evidenced by a hypochromic-shift in UV-vis absorption spectra with increasing pH. For example, the ratio of absorption at 365 nm to 472 nm of compound 3 in water, elevated from 2.5 at pH = 2.0 continuously to 3.4 at pH = 11.0. The conversion from charge neutral anhydride form to negatively charged carboxylate form switches the solubility of such probes to more polar media. These probes displayed fluorescence emission in the visible range, at 519, 440, and 504 nm, respectively. After incubation Hela cells with these probes at 10 μmol/L for 30 min, confocal microscopy displays clear cell contours with minimal noise, demonstrating efficiency of our strategy.