Preparation And Photo-Responsive Bactericidal Performance Of Ultra-Fast Assembling Bionic Surfaces

Bacteria tend to colonize on various surfaces,then reproduce and spread.The adhesive and colonization of pathogenic bacteria on surfaces like medical materials have become the main reason for infectious diseases and deaths.As the most common treatment of bacterial infections,the overuse of conventional antibiotics has resulted in a serious risk of antimicrobial resistance,which has become a new threat to humans.As an emerging material,metal-organic frameworks（MOFs）,with numerous reactive sites and tunable pore size,have shown great potential in the field of photocatalysis,drug loading,and antibacterial.Using MOFs as a bridge,combined with photosensitizers,the photo-responsive MOFs for bactericidal can transfer light into heat,reactive oxygen species,or NO to kill bacteria.With the advantage of risking no bacterial resistance,it is expected to provide a new way to solve the resistance problem induced by antibiotics.However,MOFs can barely combine with surface material directly,which has greatly limited their application.Inspired by the adhesion behavior of marine organisms,the polymerization of dopamine（DA）provides a promising avenue for achieving a stable assembly of MOFs surfaces.Nevertheless,the conventional mussel-like MOFs assembly is limited by the lengthy polymerization time（20 h）,and the strong alkaline or oxygen reaction environment,resulting in low preparation efficiency.Moreover,the traditional MOFs assembly induced by DA polymerization could cause damage to unstable particles.Therefore,there is an urgent need for a simple,feasible,and environmentally friendly strategy for light-responsive MOFs surface with efficient bactericidal properties.Herein,based on bionic principles and inspired by the adhesion behavior of marine organisms,we designed a novel mussel-like MOFs membrane platform strategy for photo-responsive antimicrobial surfaces.With the improvement of conventional mussel-like chemical particle assembly,MOFs particles could maintain the unique adsorptive property and photocatalysis property to improve the photo-responsive antibacterial performance of surfaces.The novel assembly mechanism,photo-responsive antibacterial ability,and biocompatibility of the materials were investigated,respectively.（1）To address the alkaline slow polymerization during the conventional mussel-like adhesion assembly,for the first time,we achieved the assembly of zeolitic imidazole skeleton-8（ZIF-8）nanoparticles in a neutral environment（p H=7）within 30min,which was approximately 40 times faster than traditional polydopamine assembly.Without relying on polydopamine polymerization or any catalysis initiator,ZIF-8particles were assembled by the rapid complexation reaction between the catechol in dopamine and the metal center ions in MOFs.Moreover,the underwater stability of the ZIF-8/DA-0.5 film was examined by underwater ultrasonic cleaning tests,and the universality was verified on different material surfaces.The novel bioinspired strategy provided a new design paradigm for a mild,fast,and stable MOFs film assembly.（2）To address the influence of DA-assisted MOFs film assembly technique towards the unique adsorptive property of MOFs particles,we introduced bifunctional responsive photosensitizers by leveraging the unique adsorption properties of MOFs surfaces to construct photothermal/photodynamic synergistic ZIF-8/DA-0.5/ICG antimicrobial surfaces.Under a single NIR light irradiation（808 nm,1.0 m W）,the surface can generate appropriate heat and ROS simultaneously,which also confirms the well-maintained adsorption of MOFs film.The antibacterial surface exhibit efficient killing performance for both S.aureus and E.coli.Moreover,the ZIF-8/DA-0.5/ICG antimicrobial surfaces obtained a great elimination effect on biofilms.The good cytocompatibility and blood compatibility performance of the surface showed great potential for application in medical materials and daily life protection.（3）To address the influence of DA-assisted MOFs film assembly technique towards the unique adsorptive property and photocatalysis property of MOFs particles,PCN-224 was assembled through the novel mussel-inspired MOFs assembly system.We have shortened the assembly time of the MOF film surface to 10 minutes within a neutral environment.By leveraging the adsorption properties of the PCN-224/DA₁₀surfaces,the NO catalyst L-arginine was incorporated to construct a cascade reaction PCN-224/DA₁₀/LA antimicrobial surfaces.Under visible light illumination(650 nm,20 m W cm^-2),the antibacterial ability of the PCN-224/DA₁₀ film was highly improved.The PCN-224/DA₁₀/LA surface achieved good photo-responsive bactericidal performance under a single light and can also resist biofilm formation.Moreover,the good biocompatibility and the wide irradiation range of the PCN-224/DA₁₀/LA hold significant potential for bactericidal applications in everyday household products.