Characterization of Silver Nanoparticles Obtained by a Green Route and Their Evaluation in the Bacterium of <i>Pseudomonas aeruginosa</i>

• Main Authors: Juan Carlos Martínez Espinosa, Raúl Carrera Cerritos, Maria Antonieta Ramírez Morales, Karla Paola Sánchez Guerrero, Rocio Alejandra Silva Contreras, Juan H. Macías
• Format: Article
• Language: English
• Published: MDPI AG 2020-05-01
• Series: Crystals
• Subjects: silver nanoparticles; green synthesis; antibacterial activity; <i>Pseudomonas aeruginosa</i>
• Online Access: https://www.mdpi.com/2073-4352/10/5/395

Metal nanoparticles are widely used in different areas such as biotechnology and biomedicine, for example in drug delivery, imaging and control of bacterial growth. The antimicrobial effect of silver has been identified as an alternative approach to the increasing bacterial resistance to antibiotics. Silver nanoparticles were synthesized by the green route using the <i>Geranium</i> extract as a reducing agent. The characterization was carried out by the techniques of UV-Vis spectrophotometry, transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), X-ray emitted photoelectron spectroscopy (XPS) and X-ray diffraction. Nanoparticle diameters between 15 and 50 nm were obtained and the interplanar spaces calculated from the electron diffraction pattern corresponding to a mixture of silver with 4H and <i>FCC</i> structures. To determine the minimum inhibitory concentration of silver nanoparticles (AgNPs) on the <i>Pseudomonas aeruginosa</i> bacteria (ATCC-27853), different concentrations of colloidal solution 0.36, 0.18, 0.09 and 0.05 μg/mL were evaluated as a function of the incubation time, measuring the inhibition halo and colony forming unit (CFU) during 0, 2 and 4 h of incubation. The minimum inhibitory AgNPs concentration (MIC) is 0.36 μg/mL at 0 h while the concentration of 0.18 μg/mL presents a total inhibition of the bacterium after 2 h. For the rest of the dilutions, gradual inhibitions as a function of time were observed. We evaluate the antibacterial effect of silver nanoparticles obtained by a green methodology in <i>Pseudomonas aeruginosa</i> bacteria. Finally, the colloidal nanoparticle solution can be an antibacterial alternative for different biomedical approaches.