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Due to the emergence of wide-spread infectious diseases, there is a heightened need for antimicrobial and/or antifouling coatings that can be used to prevent infection and transmission in a variety of applications, ranging from healthcare devices to public facilities. While antimicrobial coatings kill pathogenic bacteria upon contact with the surface, the antimicrobial function alone often lacks long-term effectiveness due to the accumulation of dead cells and their debris on the surface, thus reducing the performance of the coating over time. Therefore, it is desirable to develop coatings with the dual functions of antimicrobial efficacy and fouling resistance, in which antifouling coatings provide the added benefit of preventing the adhesion of dead cells and debris. Leveraging the outstanding antifouling properties of zwitterionic coatings, we synthesized copolymers with this antimicrobial-antifouling dual function by immobilizing lysozyme, a common antimicrobial enzyme, to the surface of a pyridinium-based zwitterionic copolymer. Specifically, poly(4-vinylpyridine- co -pentaflurophenyl methacrylate- co -divinyl benzene) [P(4VP-PFPMA-DVB)] thin films were synthesized by an all-dry vapor deposition technique, initiated Chemical Vapor Deposition, and derivatized using 1,3-propane sultone to obtain sulfobetaine moieties. Lysozyme, known to hydrolyze polysaccharides in the cell wall of Gram-positive bacteria, was immobilized by forming amide bonds with the copolymer coating via nucleophilic substitution of the pentafluorophenyl group. The antifouling and antibacterial performance of the novel lysozyme-zwitterionic coating was tested against Gram-positive Bacillus subtilis and Gram-negative Pseudomonas aeruginosa . A reduction in surface adhesion of 87% was achieved for P. aeruginosa , and of 75% for B. subtilis , when compared to a common poly(vinyl chloride) surface. The lysozyme-zwitterionic coating also deactivated 67% of surface-attached Gram-positive bacteria, B. subtilis . This novel dual-function material can produce anti -infection surfaces for medical devices and surgical tools, personal care products, and surfaces in public facilities. 

To reduce the severe health risk and the huge economic impact associated with the fomite transmission of SARS-CoV-2, an imidazolium-based zwitterionic polymer was designed, synthesized, and demonstrated to achieve contact deactivation of a human coronavirus under dry ambient conditions that resemble fomite transmission. The zwitterionic polymer further demonstrated excellent antifouling properties, reducing the adhesion of coronavirus and the formation of bacteria biofilms under wetted conditions. The polymer was synthesized using a substrate-independent and solvent-free process, leveraging an all-dry technique named initiated chemical vapor deposition (iCVD). The broad applicability of this approach was demonstrated by applying the polymer to a range of substrates that are curved and/or with high-aspect-ratio nano/microporous structures, which remained intact after the coating process. The zwitterionic polymer and the synthesis approach reported here present an effective solution to mitigate viral transmission without the need for manual disinfection, reducing the health and economic impact of the ongoing pandemic. 

Abstract Chemical permeation enhancers (CPEs) represent a prevalent and safe strategy to enable noninvasive drug delivery across skin‐like biological barriers such as the tympanic membrane (TM). While most existing CPEs interact strongly with the lipid bilayers in the stratum corneum to create defects as diffusion paths, their interactions with the delivery system, such as polymers forming a hydrogel, can compromise gelation, formulation stability, and drug diffusion. To overcome this challenge, differing interactions between CPEs and the hydrogel system are explored, especially those with sodium dodecyl sulfate (SDS), an ionic surfactant and a common CPE, and those with methyl laurate (ML), a nonionic counterpart with a similar length alkyl chain. Notably, the use of ML effectively decouples permeation enhancement from gelation, enabling sustained delivery across TMs to treat acute otitis media (AOM), which is not possible with the use of SDS. Ciprofloxacin and ML are shown to form a pseudo‐surfactant that significantly boosts transtympanic permeation. The middle ear ciprofloxacin concentration is increased by 70‐fold in vivo in a chinchilla AOM model, yielding superior efficacy and biocompatibility than the previous highest‐performing formulation. Beyond improved efficacy and biocompatibility, this single‐CPE formulation significantly accelerates its progression toward clinical deployment.