Zero-crosstalk and color-specific photoswitching of dual-emissive polymer nanoparticles for multiple applications

Abstract Color-specific photoswitchable dual-emissive systems are highly desirable for encryption, bioimaging and other applications. However, it is difficult to design ideal systems with ultrahigh switching efficiency and none overlap of emission signals. Herein, we report a class of zero-crosstalk dual-emissive polymer nanoparticles (ZDPNs) showing fully color-specific photoswitching property. ZDPNs contain a photochromic fluorescent diarylethene (DBTEO) and a fluorescent tetraphenylporphyrin (TPP) dye. TPP displays large Stokes shift and none spectral overlap with ring-closed form of DBTEO and therefore, blocked energy transfer effect is achieved. Upon irradiation of different lights, cyan emission of DBTEO is 100 % photo-switched, while the red fluorescence from TPP is constant. Polymer nanoparticles with different photoswitchable dual-emissive signals can be prepared by simply adjusting the feeding ratio of DBTEO and TPP. In addition, taking advantages of the facile synthesis, good water dispersibility, high-contrast of dual-emissive signals, prominent photoreversibility and photostability of the as-prepared nanoparticles, these nanoparticles exhibit great potentials in multiple applications including information encryption, anti-counterfeiting, photo-rewritable patterning and cancer cell-targeted dual-color bioimaging.