Bioinspired antimicrobial glass coatings for clear and infection-resistant surfaces

Optically transparent glass surfaces that simultaneously prevent fogging, resist contamination, and eliminate microbial growth are highly desirable for medical optics, protective equipment, and advanced architectural applications. In applications where sustained visual clarity and resistance to microbial colonization are critical for diagnostic accuracy and patient safety, as well as in self-cleaning glass panels that reduce water consumption and reliance on chemical surfactants, multifunctional surface coatings are highly desirable. Here, we report a mussel-inspired, single-step dip-coating strategy for covalent immobilization of a dopamine-conjugated quaternary antimicrobial polymer (DQP_Pr) onto glass substrates, providing a robust, scalable route to multifunctional surface engineering. Atomic force microscopy (AFM) reveals uniform nanoscale coatings, with superhydrophilicity in the Wenzel wetting regime. The modified surfaces exhibit pronounced superhydrophilicity (contact angle of ∼3-4°) while maintaining high visible transparency, enabling effective antifogging performance. The coatings further demonstrate self-cleaning behaviour by efficiently removing hydrophobic particulates upon simple water rinsing. Importantly, above a threshold coating concentration, the surfaces display potent antimicrobial activity against Gram-positive and Gram-negative bacteria as well as drug-resistant fungal strains. The coatings retain structural integrity and functional performance after repeated washing cycles and across varying temperature conditions, underscoring their durability and strong potential for practical biomedical and protective applications.