Aggregation-induced emission-active poly (β-lactam) prepared by Staudinger polymerization as specific probe to Fe3+ ions and its antimicrobial properties

For the nontraditional aggregation-induced emission (AIE) active polymers, the heterocyclic structure on the macromolecular backbone and side chains play a crucial role in its fluorescence generation. In this paper, we facilely prepared a series of poly(β-lactam) derivatives (PLTM) by Staudinger polymerization. As expected, PLTMs with four-membered heterocycles along the main-chain shows a remarkable AIE performance with the fluorescence emission at 520 nm, while no fluorescence was observed for both β-lactam (repeating unit) and a model polymer for PLTM. The fluorescence properties of PLTMs greatly depend on the intramolecular aggregation of β-lactam structures, the size of the substituents, and appropriate length of CH 2 spacer. In addition, PLTMs can specifically detect Fe 3+ ions with a limit of detection (LOD) of 7.2 μM even in the presence of other 13 metal ions. Similar to the biological activity of β-lactam, AIE-active PLTMs shows a bactericidal effect on Staphylococcus aureus and Escherichia coli with the minimum inhibitory concentration of about 8 and 4 mg/mL. In brief, the preparation and versatility of PLTMs with β-lactam structure provide useful references for designing other nontraditional AIE-active polymers as well as for ion detection and antibacterial processes.