Construction of organic compatible kaolinite antibacterial material via a dry process and its enhanced antibacterial activity

In today’s world of antibiotic abuse and bacterial resistance, it is urgent to propose a non-antibiotic solution against bacterial wound infections. Hence, the present work prepared kaolinite (KAO)-based organic antibacterial material (CA/KAO) modified with chlorhexidine acetate (CA) via a dry process. And the potential of CA/KAO in the doping preparation of antibacterial wound dressings was evaluated with poly(vinyl alcohol) (PVA) as an organic matrix. The results demonstrated that a synergistic promotion system between CA and kaolinite was formed. Kaolinite optimized the thermal stability of CA and controlled it to achieve a demand-oriented release mode of “burst + slow” release. CA was mainly attached to the surface of kaolinite by hydrogen bonding to impart its antibacterial properties and enhanced organic compatibility. For Staphylococcus aureus (S. aureus), which is prone to induce wound infections, CA/KAO showed a low-level MIC of 11.72 mg/L and achieved a 98.37% antibacterial rate by contact inactivation and released CA sterilization. CA/KAO was homogeneously dispersed in PVA film and achieved inhibition zones of 15.393 mm and 12.663 mm against S. aureus and Escherichia coli (E. coli), respectively, at 30 wt% doping. It is expected that CA/KAO would be an option for the mass production of antibacterial wound dressings.