title: The cellular responses and antibacterial activities of silver nanoparticles stabilized by different polymers.
abstract: Silver nanoparticles (AgNPs) are known for their excellent antibacterial activities. The possible toxicity, however, is a major concern for their applications. Three types of AgNPs were prepared in this study by chemical processes. Each was stabilized by a polymer surfactant, which was expected to reduce the exposure of cells to AgNPs and therefore their cytotoxicity. The polymer stabilizers included poly(oxyethylene)-segmented imide (POEM), poly(styrene-co-maleic anhydride)-grafting poly(oxyalkylene) (SMA) and poly(vinyl alcohol) (PVA). The cytotoxicity of these chemically produced AgNPs to mouse skin fibroblasts (L929), human hepatocarcinoma cells (HepG2), and mouse monocyte macrophages (J774A1) was compared to that of physically produced AgNPs and gold nanoparticles (AuNPs) as well as the standard reference material RM8011 AuNPs. Results showed that SMA-AgNPs were the least cytotoxic among all materials, but cytotoxicity was still observed at higher silver concentrations (>30 ppm). Macrophages demonstrated the inflammatory response with cell size increase and viability decrease upon exposure to 10 ppm of the chemically produced AgNPs. SMA-AgNPs did not induce hemolysis at a silver concentration below 1.5 ppm. Regarding the antibacterial activity, POEM-AgNPs and SMA-AgNPs at 1 ppm silver content showed 99.9% and 99.3% growth inhibition against E. coli, while PVA-AgNPs at the same silver concentration displayed 79.1% inhibition. Overall, SMA-AgNPs demonstrated better safety in vitro and greater antibacterial effects than POEM-AgNPs and PVA-AgNPs. This study suggested that polymer stabilizers may play an important role in determining the toxicity of AgNPs.
authors.affiliation: Institute of Polymer Science and Engineering, National Taiwan University, Taipei, Taiwan.
authors.forename: Jiang-Jen
authors.initials: JJ
authors.lastname: Lin
authors.forename: Wen-Chun
authors.initials: WC
authors.lastname: Lin
authors.forename: Rui-Xuan
authors.initials: RX
authors.lastname: Dong
authors.forename: Shan-hui
authors.initials: SH
authors.lastname: Hsu
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000737:chemistry* / Q000494:pharmacology* / Q000633:toxicity; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D004926:Escherichia coli / Q000187:drug effects; D004927:Escherichia coli Infections / Q000188:drug therapy; D006801:Humans; D008298:Maleates / Q000737:chemistry; D051379:Mice; D053758:Nanoparticles / Q000737:chemistry* / Q000633:toxicity / Q000648:ultrastructure; D011092:Polyethylene Glycols / Q000737:chemistry; D011108:Polymers / Q000737:chemistry; D011137:Polystyrenes / Q000737:chemistry; D011142:Polyvinyl Alcohol / Q000737:chemistry; D012834:Silver / Q000737:chemistry* / Q000494:pharmacology* / Q000633:toxicity; D013501:Surface-Active Agents / Q000737:chemistry
chemical_list: D000900:Anti-Bacterial Agents; D008298:Maleates; D011108:Polymers; D011137:Polystyrenes; D013501:Surface-Active Agents; C521900:poly(styrene-co-maleic anhydride); D012834:Silver; D011092:Polyethylene Glycols; D011142:Polyvinyl Alcohol