title: Synergistic influence of polyoxometalate surface corona towards enhancing the antibacterial performance of tyrosine-capped Ag nanoparticles.
abstract: We illustrate a new strategy to improve the antibacterial potential of silver nanoparticles (AgNPs) by their surface modification with the surface corona of biologically active polyoxometalates (POMs). The stable POM surface corona was achieved by utilising zwitterionic tyrosine amino acid as a pH-switchable reducing and capping agent of AgNPs. The general applicability of this approach was demonstrated by developing surface coronas of phosphotungstic acid (PTA) and phosphomolybdic acid (PMA) around AgNPs. Our investigations on Gram negative bacterium Escherichia coli demonstrate that in conjugation with AgNPs, the surface corona of POMs enhances the physical damage to the bacterial cells due to synergistic antibacterial action of AgNPs and POMs, and the ability of tyrosine-reduced AgNPs (AgNPs(Y)) to act as an excellent carrier and stabiliser for the POMs. The further extension of this study towards Gram positive bacterium Staphylococcus albus showed a similar toxicity pattern, whereas these nanomaterials were found to be biocompatible for PC3 epithelial mammalian cells, suggesting the potential of these materials towards specific antimicrobial targeting for topical wound healing applications. The outcomes of this work show that facile tailorability of nanostructured surfaces may play a considerable role in controlling the biological activities of different nanomaterials.
authors.affiliation: NanoBiotechnology Research Lab (NBRL), Centre for Advanced Materials & Industrial Chemistry (CAMIC), School of Applied Sciences, RMIT University, GPO Box 2476V, Melbourne, VIC 3000, Australia. vipul.bansal@rmit.edu.au.
authors.forename: Hemant K
authors.initials: HK
authors.lastname: Daima
authors.forename: P R
authors.initials: PR
authors.lastname: Selvakannan
authors.forename: Ahmad E
authors.initials: AE
authors.lastname: Kandjani
authors.forename: Ravi
authors.initials: R
authors.lastname: Shukla
authors.forename: Suresh K
authors.initials: SK
authors.lastname: Bhargava
authors.forename: Vipul
authors.initials: V
authors.lastname: Bansal
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000494:pharmacology; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D004926:Escherichia coli / Q000187:drug effects*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D053768:Metal Nanoparticles / Q000737:chemistry*; D008826:Microbial Sensitivity Tests; D010316:Particle Size; D012834:Silver / Q000737:chemistry / Q000494:pharmacology; D013210:Staphylococcus / Q000187:drug effects*; D013499:Surface Properties; D017973:Tungsten Compounds / Q000737:chemistry*; D014443:Tyrosine / Q000737:chemistry*; D000099294:Polyoxometalates
chemical_list: D000900:Anti-Bacterial Agents; D012834:Silver; D017973:Tungsten Compounds; D014443:Tyrosine; C102296:polyoxometalate I; D000099294:Polyoxometalates