Stable copper nanoparticles functionalized by siloxanes and its microbicidal behavior

ESTANISLAO PORTA RAMBALDI; SEBASTIÁN COGLIATI; MARCOS FRANCISCO; MARÍA VIRGINIA ROLDÁN; NADIA MAMANA; DR. ROBERTO GRAU; NORA PELLEGRI

JOURNAL OF INORGANIC AND ORGANOMETALLIC POLYMERS AND MATERIALS

SPRINGER

Lugar: Berlin; Año: 2019

1574-1443

The emergence and spread of pathogenic microbes with resistance to multiple antibiotics necessitates the development ofnew broad-spectrum microbicides. Metal nanoparticles are one such microbicide and they have been recognized for theirpotential value in fighting harmful microbes. In this work, we show the preparation and antimicrobial characterization ofcopper nanoparticles, with a small percentage of copper (I) oxide, synthesized by a chemical method based on a bottom-upapproach in a nonaqueous medium. In particular, we developed a new route to stabilize the copper nanoparticles, synthesizedin ethanol, using an aminosilane as a capping agent. The particles were later centrifuged and suspended in ethylene glycol.The morphology, structure and stability of the Cu-APTMS NPs were characterized by UV?Vis and FTIR spectroscopy,TEM, AFM and GI-XRD techniques. The presence of colloidal nanoparticles was found 4 months after synthesization anda characteristic absorption LSPR band was registered in the UV?Vis spectrum. The Cu-APTMS NPs showed a significantin vitro degradation activity against bacterial DNA, which is important in vivo microbicidal activity. The Cu-APTMS NPsshowed a strong bactericidal effect against planktonic forms of Gram-negative (Pseudomonas aeruginosa and enterohemorrhagic Escherichia coli) and Gram-positive (Staphylococcus aureus and Listeria monocytogenes) bacteria. This bactericidaleffect was also observed to severely limit the viability and germination proficiency of spores of the food-poisoning and gasgangrene producer Clostridium perfringens. In addition, pathogenic fungi (Candida tropicalis and Fusarium verticillioides)were irreversibly deactivated by treatment with Cu-APTMS NPs.