The choice of antimicrobial polymers: Hydrophilic or hydrophobic?

Owing to the spread of COVID-19, it is difficult to ignore the existence and importance of antimicrobial polymers (AMPs) because most protective appliances are made of polymers. Generally, bacteria prefer hydrophilic compounds, while fungi prefer hydrophobic ones. In recent decades, AMPs have made significant strides due to the versatile design of the functional groups or units for hydrophilic, hydrophobic, or amphiphilic performances. This review summarizes the advances of AMPs itself from the perspective of their wettability. Moreover, this study aims to clarify how the functional groups determine the interaction between the polymer and microorganisms directly affects the antimicrobial efficacy of the designed polymers. Based on the advances, the challenges and outlooks of AMPs from the perspective of wettability are systematically discussed to build a bridge between the structural design of AMPs and the requirements of practical applications.