Determinación in vitro de la actividad bactericida del óxido de grafeno, copos de pocas capas de grafeno y nanohíbrido de grafeno con plata

Abstract

To establish the bactericidal activity of graphene derivatives such as graphene oxide (GO), graphene few-layered flakes and the nanohybrid of graphene oxide with silver (GO-Ag), was the objective of this investigative work, by using a method in vitro against bacterial strains that are common agents of human infections, which were strains of Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa and Klebsiella pneumoniae. In order to carry out all the microbiological tests, the synthesis of each of the nanoparticles was first carried out through simple chemical processes, the bactericidal activity was determined by evaluating the minimum bactericidal concentration (MIC) of each nanoparticle at different concentrations against each bacterial strain at a specific concentration, this was done by dilution in broth with culture medium, LB broth, where bacterial growth was observed or not, depending on the presence of turbidity, the MIC was also determined by means of an agar diffusion in Müller Hinton culture medium, in which the inhibition halos that the bacteria presented against each nanoparticle were measured, in addition, one of the most used antibiotics was placed against infections caused by each bacterium to perform a comparison of its activity, finally it was determined whether there are significant differences between each treatment, active through ANOVA analysis together with a Tukey test. It is concluded that the nanoparticle with the greatest bactericidal effect was the graphene oxide by its physical and chemical properties of the nanomaterial specially against to Gram bacteria that have a cell wall thinner and more accessible to the nanoparticle bacterial activity. It is recommended to carry out studies at different concentrations of both nanoparticles and bacterial strains and correlate the results to verify whether the nanomaterials have greater or lesser bactericidal activity when changing the parameters used in the present study.