title: Destruction of Opportunistic Pathogens via Polymer Nanoparticle-Mediated Release of Plant-Based Antimicrobial Payloads.
abstract: The synthesis of antimicrobial thymol/carvacrol-loaded polythioether nanoparticles (NPs) via a one-pot, solvent-free miniemulsion thiol-ene photopolymerization process is reported. The active antimicrobial agents, thymol and carvacrol, are employed as "solvents" for the thiol-ene monomer phase in the miniemulsion to enable facile high capacity loading (≈50% w/w), excellent encapsulation efficiencies (>95%), and elimination of all postpolymerization purification processes. The NPs serve as high capacity reservoirs for slow-release and delivery of thymol/carvacrol-combination payloads that exhibit inhibitory and bactericidal activity (>99.9% kill efficiency at 24 h) against gram-positive and gram-negative bacteria, including both saprophytic (Bacillus subtilis ATCC 6633 and Escherichia coli ATCC 25922) and pathogenic species (E. coli ATCC 43895, Staphylococcus aureus RN6390, and Burkholderia cenocepacia K56-2). This report is among the first to demonstrate antimicrobial efficacy of essential oil-loaded nanoparticles against B. cenocepacia - an innately resistant opportunistic pathogen commonly associated with debilitating respiratory infections in cystic fibrosis. Although a model platform, these results point to promising pathways to particle-based delivery of plant-derived extracts for a range of antimicrobial applications, including active packaging materials, topical antiseptics, and innovative therapeutics.
authors.affiliation: School of Polymers and High Performance Materials, University of Southern Mississippi, Hattiesburg, MS, 39406, USA.
authors.forename: Dahlia N
authors.initials: DN
authors.lastname: Amato
authors.affiliation: School of Polymers and High Performance Materials, University of Southern Mississippi, Hattiesburg, MS, 39406, USA.
authors.forename: Douglas V
authors.initials: DV
authors.lastname: Amato
authors.affiliation: Department of Biological Sciences, University of Southern Mississippi, Hattiesburg, MS, 39406, USA.
authors.forename: Olga V
authors.initials: OV
authors.lastname: Mavrodi
authors.affiliation: School of Polymers and High Performance Materials, University of Southern Mississippi, Hattiesburg, MS, 39406, USA.
authors.forename: Dwaine A
authors.initials: DA
authors.lastname: Braasch
authors.affiliation: School of Polymers and High Performance Materials, University of Southern Mississippi, Hattiesburg, MS, 39406, USA.
authors.forename: Susan E
authors.initials: SE
authors.lastname: Walley
authors.affiliation: School of Polymers and High Performance Materials, University of Southern Mississippi, Hattiesburg, MS, 39406, USA.
authors.forename: Jessica R
authors.initials: JR
authors.lastname: Douglas
authors.affiliation: Department of Biological Sciences, University of Southern Mississippi, Hattiesburg, MS, 39406, USA.
authors.forename: Dmitri V
authors.initials: DV
authors.lastname: Mavrodi
authors.affiliation: School of Polymers and High Performance Materials, University of Southern Mississippi, Hattiesburg, MS, 39406, USA.
authors.forename: Derek L
authors.initials: DL
authors.lastname: Patton
mesh_terms: D001419:Bacteria / Q000254:growth & development*; D001424:Bacterial Infections / Q000188:drug therapy*; D063566:Biodegradable Plastics / Q000737:chemistry / Q000494:pharmacology; D000081007:Cymenes; D003692:Delayed-Action Preparations / Q000737:chemistry / Q000494:pharmacology; D039821:Monoterpenes / Q000737:chemistry / Q000494:pharmacology; D053758:Nanoparticles / Q000737:chemistry / Q000627:therapeutic use; D009894:Opportunistic Infections / Q000188:drug therapy*; D013943:Thymol / Q000737:chemistry / Q000494:pharmacology
chemical_list: D063566:Biodegradable Plastics; D000081007:Cymenes; D003692:Delayed-Action Preparations; D039821:Monoterpenes; D013943:Thymol; C073316:carvacrol
keywords: antimicrobial; carvacrol; miniemulsion polymerization; polymer nanoparticles; thymol