A powerful “one-pot” tool for fabrication of AIE-active luminescent organic nanoparticles through the combination of RAFT polymerization and multicomponent reactions

Abstract

Multicomponent reactions (MCRs) have recently received increasing attention for the synthesis of structural complexity in a single step from three or more reactants. They have also been considered as a powerful tool for the construction of sequence-controlled multifunctional polymers owing to their good substrate adaptability, simple operation and high efficiency. In this work, we reported methods that are a combination of the three-component mercaptoacetic acid locking imine (MALI) reaction and reversible addition fragmentation chain transfer (RAFT) polymerization in one pot to form luminescent organic nanoparticles (LONs) with aggregation-induced emission (AIE) features, high-brightness, great water dispersibility, ultra-small nanoscale size and excellent biocompatibility. In the reaction system, the MALI reaction and RAFT polymerization happened simultaneously in a “one-pot” route. On the one hand, the AIE-active organic dye with one amino group ((Z)-3-(4-aminophenyl)-2-(10-hexadecyl-10H-phenothiazin-3-yl)acrylonitrile) (named as Phe-NH₂) was conjugated with an aldehyde-containing monomer (10-undecenal) by the MALI reaction, while the aldehyde-containing monomer was copolymerized with the hydrophilic monomer polyethylene glycol methyl methacrylate (PEGMA) through RAFT polymerization at the same time. Compared with other fabrication strategies, “one-pot” strategies possess some advantages such as high efficiency, simplicity, and atom economy. On the other hand, due to the good applicability of RAFT polymerization and the MALI reaction, many other multifunctional AIE-active LONs could also be fabricated via adjusting the function of the substrates. Therefore, this strategy should be a general and important route for fabrication of AIE-active materials for different applications.