Release Of Metal Species Research Articles

Recent Advances in Antibacterial Metallic Species Supported on Montmorillonite Clay Mineral: A Review

This review provides information on the latest advances in inorganic materials with antimicrobial properties based on a metallic species immobilized on the clay mineral montmorillonite realized between the years 2015 and 2023. This class has shown many promising results compared to certain organic agents. Montmorillonite in natural and/or modified forms is a good platform for the storage and release of metallic species, and several researchers have worked on this mineral owing to its cation exchange capacity, low cost, biocompatibility, and local availability. The preparation methods and the properties such as the antibacterial, antifungal, and toxicological activities of this mineral are discussed. The main characteristics of this antibacterial class for the elimination of pathogenic bacteria were examined and the known weak points of its antimicrobial application are discussed, leading to suggestions for further research.

Tuned interactions of silver nanoparticles with ZSM-5 zeolite by adhesion-promoting poly(acrylic acid) deposited by electrospray ionization (ESI)

The electrospray ionization (ESI) method was used for deposition of thin films of poly(acrylic acid) (PAA) on Cu/ZSM-5 (5 wt.% Cu) and Ag–Cu/ZSM-5 (1 wt.% Ag and 4 wt.% Cu) composites. For comparative purposes, the ZSM-5 zeolite was synthesized under hydrothermal conditions and loaded with PAA under the same treating conditions as the composites. This method allowed the formation of uniform polymer films of controlled thickness on conductive substrates. The structural characteristics were characterized by X-ray photoelectron spectroscopy, Fourier-transform infrared spectroscopy, atomic force microscopy and X-ray diffraction (XRD). The deposited PAA layer over ZSM-5 acts as a common dispersing and stabilizing agent through coordination-driven guest-templated polymer via interaction of Ag+ and Cu2+ with carboxylic acid groups, thus increasing and controlling the adhesion and the release of metallic species. A short exposure to light and temperature has reduced the metal ions to Cu0 and Ag0 metallic nanoparticles. The results of XRD analysis let suggest that the interaction of Cu and Ag with carboxylic groups of PAA inhibits the formation of large metallic silver particles. These samples were being studied for their potential as antibacterial agents toward the bacterial strains such as Staphylococcus pneumonia, Bacillus subtilis, Escherichia coli and Pseudomonas aeruginosa as Gram positive and Gram negative bacteria, respectively. Aspergillus fumigatus and Candida albicans as Fungi were also evaluated. The Cu/ZSM-5 and Ag–Cu/ZSM-5 nanocomposites coated with a 10 nm thick PAA layer exhibit significant antibacterial activity.