Novel Strategy toward AIE-Active Fluorescent Polymeric Nanoparticles from Polysaccharides: Preparation and Cell Imaging

Fluorescent polymeric nanoparticles (FPNs) as novel theranostic agents for cancer diagnosis and treatment have been widely investigated in recent years. However, most FPNs were constructed with typical inorganic quantum dots, fluorescent proteins, and conventional organic dyes, which have still suffered from many obstacles such as serious cytotoxicity, easy enzymolysis, and vicious aggregation-caused fluorescence quenching (ACQ). Herein, to overcome these problems, we design and synthesize novel FPNs with a unique aggregation-induced emission (AIE) feature using resourceful and cost-effective oxidized sodium alginate (OSA) as natural polymer protected shells of FPNs. Moreover, differing from commercial or synthetic polymers such as PEG, BSA, and lecithin, sodium alginate from marine seaweeds is a cheaper, abundant source and excellent has biocompatibility. Thus-prepared AIE-active OSA-Phe-OSA FPNs by the facile Schiff base condensation have many advantages, such as strong fluorescence, great water dispersity, excellent photostability and desirable biocompatibility, and stained performance. These features endow them great potential for various biomedical applications.