Bactericidal Properties of Microwave-Activated Carbons Enhanced with Enoxil and Silver/Selenium Nanoparticles

The objectives of this study were to obtain mesoporous activated carbon with low ash content, impregnate this adsorbent with the Enoxil medicinal preparation and with Ag and Se nanoparticles, qualitatively and quantitatively analyze the immobilization processes of neutral nanoparticles on intact and oxidized activated carbons, and test the microbiological activity of the obtained samples. Microwave-activated carbons (ACMW) derived from walnut shells were impregnated with Ag and Se nanoparticles, as well as the biologically active compound Enoxil, and their microbiological properties were evaluated. To enhance the adsorbent's functionality, the activated carbon was oxidized with ozone, producing ACMWO, which contained aliphatic and aromatic carboxylic groups. This oxidation process led to a significant reduction in the specific surface area of the activated carbon. The structural parameters of the carbons were determined using nitrogen adsorption analysis, while simultaneous thermal analysis provided insights into the thermal behavior of both the oxidized and unoxidized forms. Infrared spectroscopy was employed to investigate the surface chemistry of the adsorbents. The microbiological activity of the composites was tested against Escherichia coli and Candida albicans. Kinetic studies further allowed for the estimation of the bactericidal and fungicidal action times of the activated carbons. Microwave activation allowed obtaining mesoporous ACMW carbon with a high specific surface area and a low mineral content over a short period of time. The obtained results suggest the use of activated carbons impregnated with nanoparticles and Enoxil preparation in various medical fields, in particular for the creation of bactericidal dressings that would protect the penetration of infections within the body, comfortably keeping of humidity in the area of open wounds, with adsorption and subsequent destruction of the infected exudate.