Recent advances and future prospects of polymer-based antimicrobial nanogels

The growing threat of multidrug-resistant (MDR) microbes requires innovative strategies beyond traditional antibiotics. In this context, biodegradable and biocompatible synthetic polymers provide a cost-effective solution, and the effectiveness of such materials can be further enhanced by soft polymer hydrogels with “trap and kill” mechanisms. However, macroscopic hydrogels face limitations in vivo. Nanogels—stimuli-responsive hydrogels at the nanoscale—offer a promising alternative due to their ability to undergo sol-gel transition and penetrate microbial biofilms. Despite increasing biomedical interests, full antimicrobial potential of stimuli-responsive nanogel remains underexplored, hindered by challenges such as improving stimuli responsiveness and targeting. This review highlights recent advances in the development of polymer-based antimicrobial nanogels, their advantages over other biomaterials, and explains various microbe-killing mechanisms, addressing limitations like narrow-spectrum loading and limited effectiveness against biofilm strains. These insights position nanogel systems as a promising future platform for antimicrobial applications.