Síntesis verde y caracterización de nanopartículas de óxido de cobre como potencial bactericida para el tratamiento de agua del río Chibunga

Abstract

The irrational use of antibiotics has caused bacteria to develop antibiotic-resistance mechanisms. The water, especially from those polluted rivers, considerably influences the propagation of this phenomenon, therefore, the objective of this research was to perform the green synthesis and characterization of copper oxide nanoparticles as a bactericidal potential for the water treatment of the Chibunga River. To obtain the copper oxide nanoparticles, an aqueous extract of Eucalyptus globulus (eucalyptus) was used as a reducing agent and copper sulfate as a precursor salt; its characterization was carried out by Uv-vis spectroscopy, infrared (IR) spectroscopy and scanning electron microscopy (SEM), while its bactericidal activity was evaluated by bacterial inhibition tests, performing seedings in nutritive agar, every hour of exposure of water samples to nanoparticles. For the statistical analysis, the Pearson Correlation was used, and it was possible to establish an inverse correlation between the number of colonies and the exposure time since the bacterial load was considerably reduced from the first hour the water samples came into contact with the nanoparticles. In addition, it was determined that the best conditions for the formation of nanoparticles were using a low concentration of precursor salt (0.05 M) and a temperature of 80 ° C, thus obtaining CuONPs of oval shape and size between 23-39 nm according to the analysis of scanning electron microscopy, these characteristics allowed the nanoparticles to exert their bactericidal effect. Based on these results, it is concluded that CuONPs do have bactericidal activity against Gram-positive and Gram-negative antibiotic-resistant bacterial strains present in river water samples and therefore are a good alternative for water purification.