Sustained antibacterial release of zwitterionic globular hyperbranched polymer dots intercalated into layered double hydroxides

Abstract

This study introduces zwitterionic hyperbranched polymer (HBP) dots intercalated into layered double hydroxides (LDHs) for sustained antibacterial release. The proposed zwitterionic HBPs possess a three-dimensional spherical structure; unconventional blue fluorescent luminescence; water solubility; abundant COOH, amine, and amide functional groups; anionic exchangeability for intercalating into LDH interlayers; and sustained-release antibacterial activity. The intercalation for the layered nanomaterials was determined by adding different weight ratios of HBPs to Mg–Al LDHs to investigate the changes in the interlayer distance. X-ray diffraction revealed that the LDH layer spacing increased from 8.6 to 25.5 Å, effectively expanding the interlayer spacing with increasing HBP intercalation. Additionally, Fourier-transform infrared spectroscopy revealed the functional groups of the intercalated nanohybrids. Because the peripheral functional groups of HBPs are amino (–NH₂) groups, preliminary evaluations revealed that pristine HBPs exhibited antibacterial properties. We further examined the antibacterial properties of the HBP/LDH nanohybrids. The results showed that HBPs combined with LDHs' controllable release properties can effectively achieve long-term sustained antibacterial release.