•A system of fluorescent photoswitchings based on benzimidazole-naphthopyran dyads was designed and prepared.•The fluorescence emission of benzimidazole can be efficiently modulated by photochromism of naphthopyran.•Photoinduced energy transfer is responsible for the modulation of fluorescence emission.•The non-destructive readout ability of synthesized dyads in doped PMMA film was achieved.The fluorescent photo-switching systems were prepared based on fluorescent benzimidazole and photochromic naphthopyran. Naphthopyran in this systems displayed excellent photochromic performance in tetrahydrofuran solutions and in PMMA films. The fluorescent emission of benzimidazole was modulated between “on” and “off” via the photoisomerization of naphthopyran in high-contrast due to the photoinduced energy transfer from benzimidazole to the open-form naphthopyran. Both the fluorescent photoswitching and the photochromism of benzimidazole-naphthopyran dyads in solutions and films displayed excellent fatigue resistance. The spaces between benzimidazole and naphthopyran affect the absorbance and fluorescence spectra of benzimidazole-naphthopyran dyads. The non-destructive readout ability of synthesized dyads in doped PMMA film was achieved.

•An amphiphilic naphthopyran derivative (DSNP) was designed and prepared.•DSNP can self-assemble into the LBL films with cationic quaternized poly(4-vinylpyridine).•DSNP also assemble into light-responsive micelles with polyethylene glycol–triethylamine bromide.•Naphthopyran displayed a markedly slower fading rate in LBL films.•The photochromic reaction of naphthopyran induced disassembly and re-assembly of micelles.An amphiphilic naphthopyran derivative (DSNP) with negative-charged di-sulfatoethoxy was first designed and synthesized. DSNP was used to prepare the LBL self-assembly films with cationic quaternized poly(4-vinylpyridine) (P4VPQ). The multilayer assembly process was monitored via UV–Vis spectra and the DSNP displayed a significant slow fading rate in film. In addition, DSNP was also used as the light-responsive group to fabricate light-responsive micelles with polyethylene glycol–triethylamine bromide (PEG–NEt3). The photoisomerization of naphthopyran moieties can rapidly and reversibly tune the disassembly and re-assembly of the micelles. The changes of fluorescent spectra of Nile Red (NR) in water solution of polymeric micelles demonstrated that the polymeric micelle can be used as nanocarriers to encapsulate, release and re-encapsulate guest solutes on demand controlling of light irradiation. The results indicate that the amphiphilic naphthopyran can be used in both optical-switches and biomedical area for drug delivery.