title: An environmentally benign antimicrobial nanoparticle based on a silver-infused lignin core.
abstract: Silver nanoparticles have antibacterial properties, but their use has been a cause for concern because they persist in the environment. Here, we show that lignin nanoparticles infused with silver ions and coated with a cationic polyelectrolyte layer form a biodegradable and green alternative to silver nanoparticles. The polyelectrolyte layer promotes the adhesion of the particles to bacterial cell membranes and, together with silver ions, can kill a broad spectrum of bacteria, including Escherichia coli, Pseudomonas aeruginosa and quaternary-amine-resistant Ralstonia sp. Ion depletion studies have shown that the bioactivity of these nanoparticles is time-limited because of the desorption of silver ions. High-throughput bioactivity screening did not reveal increased toxicity of the particles when compared to an equivalent mass of metallic silver nanoparticles or silver nitrate solution. Our results demonstrate that the application of green chemistry principles may allow the synthesis of nanoparticles with biodegradable cores that have higher antimicrobial activity and smaller environmental impact than metallic silver nanoparticles.
authors.affiliation: Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, North Carolina 27695, USA.
authors.forename: Alexander P
authors.initials: AP
authors.lastname: Richter
authors.affiliation: Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, North Carolina 27695, USA.
authors.forename: Joseph S
authors.initials: JS
authors.lastname: Brown
authors.affiliation: Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, North Carolina 27695, USA.
authors.forename: Bhuvnesh
authors.initials: B
authors.lastname: Bharti
authors.affiliation: United States Environmental Protection Agency, Office of Research and Development, RTP, North Carolina 27711, USA.
authors.forename: Amy
authors.initials: A
authors.lastname: Wang
authors.affiliation: United States Environmental Protection Agency, Office of Research and Development, RTP, North Carolina 27711, USA.
authors.forename: Sumit
authors.initials: S
authors.lastname: Gangwal
authors.affiliation: United States Environmental Protection Agency, Office of Research and Development, RTP, North Carolina 27711, USA.
authors.forename: Keith
authors.initials: K
authors.lastname: Houck
authors.affiliation: United States Environmental Protection Agency, Office of Research and Development, RTP, North Carolina 27711, USA.
authors.forename: Elaine A
authors.initials: EA
authors.lastname: Cohen Hubal
authors.affiliation: Surfactant and Colloid Group, Department of Chemistry, University of Hull, Hull HU6 7RX, UK.
authors.forename: Vesselin N
authors.initials: VN
authors.lastname: Paunov
authors.affiliation: Physical Chemistry and Soft Matter, Wageningen University, Wageningen, The Netherlands.|Department of Mechanical Engineering, University College London, Torrington Place, London WC1E 7JE, UK.
authors.forename: Simeon D
authors.initials: SD
authors.lastname: Stoyanov
authors.affiliation: Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, North Carolina 27695, USA.
authors.forename: Orlin D
authors.initials: OD
authors.lastname: Velev
mesh_terms: D000818:Animals; D000890:Anti-Infective Agents / Q000737:chemistry* / Q000494:pharmacology* / Q000633:toxicity; D001419:Bacteria / Q000187:drug effects; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D015169:Colony Count, Microbial; D004625:Embryo, Nonmammalian / Q000187:drug effects; D057166:High-Throughput Screening Assays; D006801:Humans; D008031:Lignin / Q000737:chemistry* / Q000633:toxicity; D050296:Microbial Viability / Q000187:drug effects; D053758:Nanoparticles / Q000737:chemistry* / Q000633:toxicity; D051381:Rats; D012834:Silver / Q000737:chemistry* / Q000494:pharmacology* / Q000633:toxicity; D015027:Zebrafish
chemical_list: D000890:Anti-Infective Agents; D012834:Silver; D008031:Lignin