From a Molecular Toolbox to a Toolbox for Photoswitchable Fluorescent Polymeric Nanoparticles

Switchable organic fluorescent materials are attracting much interest in many fields including flexible display, information storage, anti-counterfeit, and bioimaging, due to their prominent properties and relatively low cost. Herein, a class of novel photoswitchable fluorescent polymeric nanoparticles (PFPNs) toolbox that shows switchable full-colored emission including white light is described. This nanoparticles toolbox consists of a series of reversibly photoswitchable and non-PFPNs with red, green, and blue fluorescence, and is built up from three primary fluorescent dyes and a photochromic diarylethene molecule, through a facile one-pot miniemulsion method. The as-prepared PFPNs display the merits of high fluorescence resonance energy transfer efficiency and fluorescence quantum yield, rapid responsiveness, prominent photoreversibility, and brilliant long-term fluorescence stability ( ≈ 6 weeks). They enable switchable emission between white light and any visible color on-demand in both solution and film states. Their potential in complex fluorescent encryption and photoswitchable white light-emitting diode is described and its great potential in anti-counterfeiting technology, data encryption, and the next generation of optoelectronic materials is foreseen.