title: Design and characterization of antimicrobial usnic acid loaded-core/shell magnetic nanoparticles.
abstract: The application of magnetic nanoparticles (MNPs) in medicine is considered much promising especially because they can be handled and directed to specific body sites by external magnetic fields. MNPs have been investigated in magnetic resonance imaging, hyperthermia and drug targeting. In this study, properly functionalized core/shell MNPs with antimicrobial properties were developed to be used for the prevention and treatment of medical device-related infections. Particularly, surface-engineered manganese iron oxide MNPs, produced by a micro-emulsion method, were coated with two different polymers and loaded with usnic acid (UA), a dibenzofuran natural extract possessing antimicrobial activity. Between the two polymer coatings, the one based on an intrinsically antimicrobial cationic polyacrylamide (pAcDED) resulted to be able to provide MNPs with proper magnetic properties and basic groups for UA loading. Thanks to the establishment of acid-base interactions, pAcDED-coated MNPs were able to load and release significant drug amounts resulting in good antimicrobial properties versus Staphylococcus epidermidis (MIC = 0.1 mg/mL). The use of pAcDED having intrinsic antimicrobial activity as MNP coating in combination with UA likely contributed to obtain an enhanced antimicrobial effect. The developed drug-loaded MNPs could be injected in the patient soon after device implantation to prevent biofilm formation, or, later, in presence of signs of infection to treat the biofilm grown on the device surfaces.
authors.affiliation: Department of Chemistry, Sapienza University of Rome, Italy; School of Pharmacy, University of Nottingham, University Park, Nottingham NG7 2RD United Kingdom.
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Taresco
authors.affiliation: Department of Chemistry, Sapienza University of Rome, Italy. Electronic address: iolanda.francolini@uniroma1.it.
authors.forename: Iolanda
authors.initials: I
authors.lastname: Francolini
authors.affiliation: Technical Unit for Material Technologies, Agenzia Nazionale per le Nuove Tecnologie, l'Energia e lo Sviluppo Economico Sostenibile (ENEA), Casaccia Research Centre, Rome, Italy.
authors.forename: Franco
authors.initials: F
authors.lastname: Padella
authors.affiliation: Technical Unit for Material Technologies, Agenzia Nazionale per le Nuove Tecnologie, l'Energia e lo Sviluppo Economico Sostenibile (ENEA), Casaccia Research Centre, Rome, Italy.
authors.forename: Mariangela
authors.initials: M
authors.lastname: Bellusci
authors.affiliation: Istituto Italiano di Tecnologia, Center for Nanotechnology Innovation @NEST, Piazza San Silvestro, 12-56127 Pisa, Italy.
authors.forename: Adriano
authors.initials: A
authors.lastname: Boni
authors.affiliation: INSTM and Department of Chemistry, University of Florence, Italy.
authors.forename: Claudia
authors.initials: C
authors.lastname: Innocenti
authors.affiliation: Department of Chemistry, Sapienza University of Rome, Italy.
authors.forename: Andrea
authors.initials: A
authors.lastname: Martinelli
authors.affiliation: Department of Chemistry, Sapienza University of Rome, Italy.
authors.forename: Lucio
authors.initials: L
authors.lastname: D'Ilario
authors.affiliation: Department of Chemistry, Sapienza University of Rome, Italy. Electronic address: antonella.piozzi@uniroma1.it.
authors.forename: Antonella
authors.initials: A
authors.lastname: Piozzi
mesh_terms: D000890:Anti-Infective Agents / Q000737:chemistry* / Q000494:pharmacology*; D001572:Benzofurans / Q000737:chemistry*; D008280:Magnetics; D058185:Magnetite Nanoparticles / Q000737:chemistry*; D013212:Staphylococcus epidermidis / Q000187:drug effects
chemical_list: D000890:Anti-Infective Agents; D001572:Benzofurans; D058185:Magnetite Nanoparticles; C073339:usnic acid
keywords: Drug targeting; Magnetic nanoparticles; Medical device-related infections; Staphylococcus epidermidis; Usnic acid