Thermostably photoswitchable red fluorescent polymeric nanoparticles for rewritable fluorescence patterning and zebrafish imaging

Abstract

Photoswitchable fluorescent nanomaterials (PFNs) are gaining popularity in a variety of applications including bioimaging, information encryption and anti-counterfeiting. However, the photoswitching properties of traditional PFNs are still far from application, due to the complex background fluorescence interference, the lower brightness and contrast, the poor thermal and light stability. To tackle this question, we developed new thermostably photoswitchable red fluorescent polymer nanoparticles (TPFPNs) through a facile miniemulsion polymerization in this study. TPFPNs contained a high quantum yield of red fluorescence dye, 1,6,7,12-tetra(p-tBu-phenoxy)-3,4,9,10-di(anhydride) perylene (TBPDI) as donor and a thermostably photochromic diarylethene derivative (DTEDA) as acceptor. When DTEDA changed from its opened-ring state (DTEDA-o) to its closed-ring form (DTEDA-c) after UV irradiation, fluorescence resonance energy transfer (FRET) process occurred from TBPDI to DTEDA-c, which induced the transition from red fluorescence to quenching state. In addition, TPFPNs showed adjustable FRET efficiency, outstanding thermal stability, prominent long-term stability, superior photoreversibility, as well as high contrast of on/off fluorescence. Moreover, TPFPNs were successfully used for photo-rewritable patterning and reversible fluorescence bioimaging in Zebrafish.