Damage on Escherichia coli and Staphylococcus aureus using white light photoactivation of Au and Ag nanoparticles
Por:
Mendez-Pfeiffer, Pablo A., Soto Urzua, Lucia, Sanchez-Mora, Enrique, Gonzalez, Ana L., Romo-Herrera, J. M., Gervacio Arciniega, Jose Juan, Martinez Morales, Luis Javier
Publicada:
1 ene 2019
Categoría:
Physics and astronomy (miscellaneous)
Resumen:
Bactericidal efficiency of Au and Ag nanoparticles (NPs) is reported with and without photoactivation by white light. Au and Ag NPs were synthesized with an average size of 14 ± 1.2 nm and of 4.6 ± 0.5 nm, respectively. The size distribution of the Ag colloid was relatively wide. Less than 4 % of these NPs were largely decahedral, which, based on numerical calculations, determined the position of the optical band. In contrast, the Au colloid had a narrow optical band; a concentration of 1.3 µ g / ml was determined by theoretical and experimental spectra. Ag and Au NPs showed a superficial charge of - 35 mV and + 57 mV due to the presence of the citrate ions and cetyltrimethylammonium bromide on their surface, respectively. The effect of the NPs concentration on the viability of Escherichia coli and Staphylococcus aureus strains was investigated. It was found that Ag NPs were more effective against E. coli than Au NPs, whereas Au NPs were more effective against S. aureus than Ag NPs. The induced damage to the bacteria by the NPs was evaluated by AFM. The images show that the bacterial cell wall was changed in shape and in surface roughness, being more noticeable in S. aureus than in E. coli. The bactericidal activity of the photoactivated Ag NPs was almost doubled for both bacteria, whereas for the Au NPs, no bactericidal enhancement was observed for either strain. This can be explained by the high efficiency of Ag NPs to absorb white light and the consequent creation of hot spots that contribute to kill the bacteria. © 2019 Author(s).
Filiaciones:
Mendez-Pfeiffer, Pablo A.:
Centro de Investigaciones en Ciencias Microbiológicas, Instituto de Ciencias, Benemérita Universidad Autónoma de Puebla, Puebla, 72570, Mexico
Benemerita Univ Autonoma Puebla, Inst Ciencias, Ctr Invest Ciencias Microbiol, Puebla 72570, Mexico
Soto Urzua, Lucia:
Centro de Investigaciones en Ciencias Microbiológicas, Instituto de Ciencias, Benemérita Universidad Autónoma de Puebla, Puebla, 72570, Mexico
Benemerita Univ Autonoma Puebla, Inst Ciencias, Ctr Invest Ciencias Microbiol, Puebla 72570, Mexico
Sanchez-Mora, Enrique:
Instituto de Física, Benemérita Universidad Autónoma de Puebla, Apartado Postal J48, Puebla, 72570, Mexico
Benemerita Univ Autonoma Puebla, Inst Fis, Apartado Postal J48, Puebla 72570, Mexico
Gonzalez, Ana L.:
Instituto de Física, Benemérita Universidad Autónoma de Puebla, Apartado Postal J48, Puebla, 72570, Mexico
Benemerita Univ Autonoma Puebla, Inst Fis, Apartado Postal J48, Puebla 72570, Mexico
Romo-Herrera, J. M.:
Centro de Nanociencias y Nanotecnología, UNAM, Ensenada B.C. C.P., 22800, Mexico
UNAM, Ctr Nanociencias & Nanotecnol, Ensenada 22800, Baja California, Mexico
Gervacio Arciniega, Jose Juan:
CONACYT-Facultad de Ciencias Físico-Matemáticas, Benemérita Universidad Autónoma de Puebla, Av. San Claudio y Av. 18 Sur, Puebla C.P., 72570, Mexico
Benemerita Univ Autonoma Puebla, CONACYT Fac Ciencias Fis Matemat, Av San Claudio & Av 18 Sur, Puebla 72570, Mexico
Martinez Morales, Luis Javier:
Centro de Investigaciones en Ciencias Microbiológicas, Instituto de Ciencias, Benemérita Universidad Autónoma de Puebla, Puebla, 72570, Mexico
Benemerita Univ Autonoma Puebla, Inst Ciencias, Ctr Invest Ciencias Microbiol, Puebla 72570, Mexico
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