title: Influence of scaffold size on bactericidal activity of nitric oxide-releasing silica nanoparticles.
abstract: A reverse microemulsion synthesis was used to prepare amine-functionalized silica nanoparticles of three distinct sizes (i.e., 50, 100, and 200 nm) with similar amine content. The resulting hybrid nanoparticles, consisting of N-(6-aminohexyl)aminopropyltrimethoxysilane and tetraethoxysilane, were highly monodisperse in size. N-Diazeniumdiolate nitric oxide (NO) donors were subsequently formed on secondary amines while controlling reaction conditions to keep the total amount of NO released constant for each particle size. The bactericidal efficacy of the NO-releasing nanoparticles against Pseudomonas aeruginosa increased with decreasing particle size. Additionally, smaller diameter nanoparticles were found to associate with the bacteria at a faster rate and to a greater extent than larger particles. Neither control (non-NO-releasing) nor NO-releasing particles exhibited toxicity toward L929 mouse fibroblasts at concentrations above their respective minimum bactericidal concentrations. This study represents the first investigation of the bactericidal efficacy of NO-releasing silica nanoparticles as a function of particle size.
authors.affiliation: Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA.
authors.forename: Alexis W
authors.initials: AW
authors.lastname: Carpenter
authors.forename: Danielle L
authors.initials: DL
authors.lastname: Slomberg
authors.forename: Kavitha S
authors.initials: KS
authors.lastname: Rao
authors.forename: Mark H
authors.initials: MH
authors.lastname: Schoenfisch
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000737:chemistry* / Q000494:pharmacology; D002460:Cell Line; D051379:Mice; D008826:Microbial Sensitivity Tests; D053758:Nanoparticles; D009569:Nitric Oxide / Q000737:chemistry*; D020030:Nitric Oxide Donors / Q000494:pharmacology; D010316:Particle Size; D011550:Pseudomonas aeruginosa; D012822:Silicon Dioxide
chemical_list: D000900:Anti-Bacterial Agents; D020030:Nitric Oxide Donors; D009569:Nitric Oxide; D012822:Silicon Dioxide