Silver-Containing Nanodispersions on the Basis of Polymer Derivatives of Aromatic Amino Acids: Synthesis, Morphology, Spectral Characteristics, and Antimicrobial Activity

Nanodispersions based on silver nanoparticles (Ag⁰) are synthesized In the presence of polymer complexones (copolymers of N-vinylpyrrolidone (VP) with p-methacryloylaminobenzoic (MABA-Na) and p-methacryloylaminosalicylic acid (MASA-Na)). The spectral and morphological characteristics of the nano-dispersions are investigated using ultraviolet (UV) spectroscopy and atomic force microscopy (AFM); the minimum energy (E_g) of electron transfer from the valence band to the conduction band of the metal is estimated; and the influence of the nature of the chelate unit on the band gap E_g, as well as on the size of spherical nanoparticles is shown. The reduction of silver ions in water in the presence of copolymers VP-MABA-Na and VP-MASA-Na, due to fairly good screening, makes it possible to obtain spherical nanostructures with a diameter not exceeding 200 nm. In the case of Ag⁰/VP-MASA-Na, massive dense oval-shaped aggregates are formed, which consist of small densely packed nanostructures. The silver-containing dispersions Ag⁰/VPрMABA-Na and Ag⁰/VP-MASA-Na tested against E. coli, P. aeruginosa, and S. aureus bacteria show pronounced antimicrobial activity, significantly superior to the activity of the reference drug, Protargol.