Ultrabright and biocompatible AIE dye based zwitterionic polymeric nanoparticles for biological imaging

Abstract

The development of novel fluorescent nanoprobes with remarkable optical properties, suitable particle size, high water dispersibility and good biocompatibility has recently attracted increasing interest for various biomedical applications. In this work, a novel type of luminescent polymeric nanoparticle based on polymerizable dyes with aggregation induced emission (AIE) properties and a zwitterionic monomer were prepared via reversible addition fragmentation chain transfer polymerization. Due to their amphiphilic properties, these copolymers could facilely self-assemble into AIE dye containing luminescent zwitterionic polymeric nanoparticles, which were characterized by a series of characterization techniques including transmission electronic microscopy, Fourier transform infrared spectroscopy, fluorescence spectroscopy and X-ray photoelectron spectroscopy. The results showed that these luminescent polymeric nanoparticles with diameters of tens of nanometers showed high water dispersibility and strong fluorescence in aqueous solution. To explore their potential for biomedical applications, biocompatibility and cell uptake behavior of these luminescent polymeric nanopartilces were further evaluated. We demonstrated that these polymeric nanoparticles are biocompatible with A549 cells and promising for bioimaging applications. Taken advantage of these merits of the AIE dye based zwitterionic polymeric nanoparticles, which could elegantly avoid the aggregation induced quenching of conventional organic dyes and nonbiodegradability of fluorescent inorganic nanoparticles, the ultrabright and biocompatible luminescent polymeric nanoparticles described in this work should be of highly potential for various biomedical applications.