Antibacterial properties of nickel and aluminum nanoparticles

Abstract

The high level of polyantibiotic resistance of pathogenic bacteria dictates the need to search for and develop new classes of substances that have a different mechanism of action compared to antibiotics. As alternatives, metal nanoparticles can be considered, especially if an environmentally friendly method of production is used in the process of creating the latter. Nickel and aluminum nanoparticles were synthesized by the laser ablation method in liquid, which belongs to the “green” chemistry methods. The optical, structural, and morphological properties of the synthesized nanoparticles were studied using a spectrophotometer, atomic force and transmission electron microscopy, respectively. The antibacterial properties of nickel and aluminum nanoparticles were analyzed on the example of two strains of Gram-positive, five strains of Gram-negative bacteria. The performed studies have shown that nickel nanoparticles have characteristic absorption maxima in the middle ultraviolet (285 nm) and red (750 nm) regions of the spectrum, the optical density spectrum of a colloidal solution of aluminum nanoparticles does not have pronounced maxima. Atomic force and transmission electron microscopy revealed that the nanoparticles of the studied metals are predominantly spherical in shape and their diameters correspond to the range (20–60 nm). At the same time, in an insignificant amount, individual conglomerates (≥100 nm in size) are observed. The performed bacteriological studies have revealed the presence of pronounced antimicrobial properties in nickel and aluminum nanoparticles in relation to the most common clinical pathogenic strains of both Gram-positive and Gram-negative microorganisms. Nickel and aluminum nanoparticles synthesized by the laser ablation method in liquid are characterized by a relatively uniform shape, a small scatter in size, and have an antibacterial effect against the most common clinical pathogenic microbial strains, which makes them a unique class of substances in terms of developing new ways to combat antibiotic resistance in medicine, in general, and in surgery, in particular.