title: Sunlight-Triggered Nanoparticle Synergy: Teamwork of Reactive Oxygen Species and Nitric Oxide Released from Mesoporous Organosilica with Advanced Antibacterial Activity.
abstract: Colonization of surfaces by microorganisms is an urging problem. In combination with the increasing antibiotic resistance of pathogenic bacteria, severe infections are reported more frequently in medical settings. Therefore, there is a large demand to explore innovative surface coatings that provide intrinsic and highly effective antibacterial activity. Materials containing silver nanoparticles have been developed in the past for this purpose, but this solution has come into criticism due to various disadvantages like notable toxicity against higher organisms, the high price, and low abundance of silver. Here, we introduce a new, sunlight-mediated organosilica nanoparticle (NP) system based on silver-free antibacterial activity. The simultaneous release of nitric oxide (NO) in combination with singlet oxygen and superoxide radicals (O2(•-)) as reactive oxygen species (ROS) leads to the emergence of highly reactive peroxynitrite molecules with significantly enhanced biocidal activity. This special cooperative effect can only be realized, if the ROS-producing moieties and the functional entities releasing NO are spatially separated from each other. In one type of particle, Rose Bengal as an efficient singlet oxygen ((1)O2) producer was covalently bound to SH functionalities applying thiol-ene click chemistry. "Charging" the second type of particles with NO was realized by quantitatively transferring the thiol groups into S-nitrosothiol functionalities. We probed the oxidation power of ROS-NP alone and in combination with NO-NP using sunlight as a trigger. The high antibacterial efficiency of dual-action nanoparticles was demonstrated using disinfection assays with the pathogenic bacterium Pseudomonas aeruginosa.
authors.affiliation: Department of Chemistry and ‡Department of Biology, University of Konstanz , Konstanz D-78457, Germany.
authors.forename: Julia
authors.initials: J
authors.lastname: Gehring
authors.affiliation: Department of Chemistry and ‡Department of Biology, University of Konstanz , Konstanz D-78457, Germany.
authors.forename: Bastian
authors.initials: B
authors.lastname: Trepka
authors.affiliation: Department of Chemistry and ‡Department of Biology, University of Konstanz , Konstanz D-78457, Germany.
authors.forename: Nele
authors.initials: N
authors.lastname: Klinkenberg
authors.affiliation: Department of Chemistry and ‡Department of Biology, University of Konstanz , Konstanz D-78457, Germany.
authors.forename: Hannah
authors.initials: H
authors.lastname: Bronner
authors.affiliation: Department of Chemistry and ‡Department of Biology, University of Konstanz , Konstanz D-78457, Germany.
authors.forename: David
authors.initials: D
authors.lastname: Schleheck
authors.affiliation: Department of Chemistry and ‡Department of Biology, University of Konstanz , Konstanz D-78457, Germany.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Polarz
mesh_terms: D057930:Click Chemistry; D004202:Disinfectants / Q000737:chemistry / Q000494:pharmacology*; D004203:Disinfection / Q000379:methods*; D004357:Drug Synergism; D053758:Nanoparticles / Q000737:chemistry*; D009569:Nitric Oxide / Q000737:chemistry / Q000494:pharmacology*; D017646:Organosilicon Compounds / Q000737:chemistry / Q000494:pharmacology*; D055668:Photochemical Processes; D011550:Pseudomonas aeruginosa / Q000187:drug effects; D017382:Reactive Oxygen Species / Q000737:chemistry / Q000494:pharmacology*; D012395:Rose Bengal / Q000737:chemistry; D013438:Sulfhydryl Compounds / Q000737:chemistry / Q000494:pharmacology; D013472:Sunlight
chemical_list: D004202:Disinfectants; D017646:Organosilicon Compounds; D017382:Reactive Oxygen Species; D013438:Sulfhydryl Compounds; D012395:Rose Bengal; D009569:Nitric Oxide