Synthesis and Antibacterial Activities of Boronic Acid-Based Recyclable Spherical Polymer Brushes

Crosslinked poly(4-vinylbenzyl chloride) (PVBC) microbead was prepared by suspension polymerization. Various spherical polymer brushes (SPBs) were produced by grafting polymeric chains on their surfaces via surface initiated-atom transfer radical polymerization (SI-ATRP) using 4-vinylphenyl boronic acid (VPBA), 2-(dimethylamino)ethyl methacrylate (DMA), and quaternized DMA (QDMA). PVBC-g-PDMA, PVBC-g-PQDMA, PVBC-g-PVPBA, PVBC-g-P(VPBA-b-DMA), PVBC-g-P(VPBA-co-DMA) and PVBC-g-P(VPBA-b-QDMA) SPBs were characterized using nuclear magnetic resonance spectroscopy, attenuated total reflection Fourier transform infrared spectroscopy, thermogravimetric analysis, and scanning electron microscopy. Antibacterial activities of the synthesized SPBs were investigated against Escherichia coli and Staphylococcus aureus in nutrient and nutrient free media. Although PVBC-g-P(VPBA-b-DMA) SPB provided high antibacterial activity in the nutrient containing media due to its antibacterial, anti-biofilm and anti-QS properties, PVBC-g-P8QDMA SPB was found to be more effective in nutrient free media. Considering repeatable antibacterial activity, the PVBC-g-P(VPBA-b-8QDMA) SPB has advantageous over PVBC-g-P(VPBA-b-DMA) and PVBC-g-P8QDMA SPBs for long-term applications such as wastewater treatment in fluidized bad system.