INFIQC   05475
INSTITUTO DE INVESTIGACIONES EN FISICO- QUIMICA DE CORDOBA
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
A silver-plated gold heart. A promising alternative against resistant bacteria
Autor/es:
SILVERO MJ; FASCIANI C; ANGHEL A; SCAIANO JC; ARGÜELLO G A; BECERRA M C
Lugar:
Córdoba
Reunión:
Otro; RICiFa 3° Reunión Internacional de Ciencias Farmacéuticas.; 2014
Institución organizadora:
Dpto. Farmacia. Fac. Ciencias Químicas-UNC y la Univ. Nac. de Rosario.
Resumen:
A SILVER-PLATED GOLD HEART. A PROMISING ALTERNATIVE AGAINST RESISTANT BACTERIA Silvero, MJ1,2,3; Fasciani, C2; Anghel, A2; Scaiano, JC2; Argüello, GA1 and Becerra, MC3. jsilvero@fcq.unc.edu.com.ar 1 Instituto de Investigaciones en Físico Química de Córdoba (INFIQC) CONICET-UNC, Departamento de Físico Química. Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Ciudad Universitaria, X5000HUA Córdoba Argentina. 2 Department of Chemistry and Centre for Catalysis Research and Innovation, University of Ottawa, 10 Marie Curie, Ottawa, Ontario, K1N 6N5, Canada 3 Instituto Multidisciplinario de Biología Vegetal (IMBIV), CONICET and Dpto. de Farmacia, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba. Ciudad Universitaria, X5000HUA Córdoba, Argentina. Increase of pathogens resistance to available drugs is a matter of concern for pharmaceutics all around the world. In this work, we present gold nanoparticles (AuNPs) and a novel kind of coreshell nanoparticle as efficient alternative therapies against bacteria strains not sensitive to clinically used antibiotics. When a metal nanoparticle interacts with light, having a wavelength longer than the dimensions of the particle itself, Surface Plasmon Resonance (SPR) takes place. In case of gold, SPR absorptions occur in the visible range; this allows us to use cheap and harmless LEDs (525nm) as radiation source. Gold nanoparticles were synthesized according to Turkevich method and the new nanomaterial reported here consists of a gold core, encapsulated in a silver shell and stabilized with a dipeptide, specifically aspartame. The gold core is designed for the purpose of efficient heat delivery through established plasmonic mechanisms. The silver shell retains the antibacterial properties that are now well characterized in the case of AgNP. The surface protection with aspartame (Asp) leads to excellent aqueous stabilization with long shelf life. Further, aspartame is non-toxic, remarkably inexpensive and easy to replace by another molecule of interest. Complete inhibition was achieved only in samples irradiated of three clinical Pseudomonas aeruginosa strains and for a clinical strain of Escherichia coli extended-spectrum β-lactamases (ESBL). Nine hours of irradiation were necessary when bacterial suspensions were treated with AuNPs and just 6 hours were needed when Asp@Ag@AuNPs were used. These results would suggest that complete inhibition was achieved earlier in samples irradiated and treated with Asp@Ag@AuNPs rather with AuNPs. This antibacterial activity could be attributed to the synergism between the silver shell and the plasmon excitation of gold core. TEM images revealed membrane structural damage of the bacillus. KEYWORDS: nanoparticles, bacterial resistant strains, light