Green Synthesis and Characterization of Antimicrobial Synergistic AgCl/BAC Nanocolloids

Abstract

All over the world, one of the major challenges is the green synthesis of potential materials against antimicrobial resistance and viruses. This study demonstrates a simple method like chemistry lab titration to synthesize green, facile, scalable, reproducible, and stable synergistic silver chloride/benzyldimethylhexadecyl-ammonium chloride (AgCl/BAC) colloidal Nanoantimicrobials (NAMs). Nanocolloidal dispersions of AgCl in an aqueous medium are prepared by using silver nitrate (AgNO 3 ) as precursor and BAC as both sources of chloride and stabilizer, holding an asymmetric molecular structure. The synthetic approach is scalable and green. Both the morphology and stability of AgCl/BAC nanocolloids (NCs) were investigated as a function of different molar fractions of the reagents. AgCl/BAC NCs were characterized by transmission electron microscopy (TEM) and X-ray photoelectron and UV–vis spectroscopies. Zeta potential measurements revealed increasing positive potential values at every stage of the synthesis. Size distribution and hydrodynamic diameter of the particles were measured by dynamic light scattering (DLS), which predicted the formation of BAC layered structures associated with the AgCl nanoparticles (NPs). Small-angle X-ray scattering (SAXS) experiments verify the thickness of the BAC bilayer around AgCl. The produced AgCl/BAC NCs probably have synergistic antimicrobial properties from the AgCl core and the biocide BAC shell. AgCl/BAC NCs stability over months was investigated. The experimental evidence supports the morphological stability of the AgCl/BAC NCs, while higher positive zeta potential values anticipate a long-term antimicrobial effect: a higher surface charge causes NPs to be potentially more lethal to bacteria. AgCl/BAC antimicrobial aqueous colloidal suspensions will be used as additives for the industrial production of antimicrobial coatings.

A scalable route to quaternary ammonium-functionalized AgCl colloidal antimicrobials inhibiting food pathogenic bacteria and biofilms

“…AgCl/DDAC NCs were drop-cast onto copper grids (300 mesh, Agar Scientific) and AgCl/DDoAC NCs onto carbon grids (300 mesh, Agar Scientific) in volumes of 3–5 μL for each sample. Dynamic light scattering (DLS) measurements were performed using a Zetasizer Nano ZS instrument (Malvern Instruments, Ltd., Worcestershire, UK) as described previously [ 40 ]. The Zetasizer Nano ZS is equipped with a 4 mW He−Ne laser and an automatic laser attenuator, and with an avalanche photodiode detector.…”

“…However, in view of the rapid, large-scale production of antimicrobial agents, green character, cost-effectiveness, scalability, and versatility should be considered. We recently investigated the addition of antimicrobial QAC, e.g., benzalkonium chloride (BAC) with AgCl, to improve the stability of NCs, provided that the aromatic BAC moieties act as a bilayer around AgCl NPs, forming a core-shell structure [ 40 ]. However, in that preliminary study we did not investigate the potential of these nanocolloids as synergistic antimicrobial or antibiofilm agents.…”

Chitosan Edible Films and Coatings with Added Bioactive Compounds: Antibacterial and Antioxidant Properties and Their Application to Food Products: A Review

“…Likewise, chitosan films/coatings can act as a vehicle carrier of bioactive substances such as polyphenolic compounds, bacteriocins, essential oils, or plant extracts to develop novel active packaging materials with antioxidant and antimicrobial properties [ 9 , 10 ]. To improve their antibacterial properties, chitosan edible film also could be combined with different green synthesized materials as silver nanoparticles using plant extracts that help in the reducing, stabilizing, and capping of these nanoparticles [ 11 , 12 ]. However, this technology is taking its first steps and requires many and more in-depth studies to reliably determine all the possibilities it may have.…”

Removal of Pollutants by Ferrihydrite Nanoparticles Combined with Brij L4 Self-Assembled Nanostructures

“…Interactions between self-assembled nanostructures of surfactants and inorganic nanoparticles (NPs) are of interest for both natural and engineered systems. − Ag NPs are widely used in consumer products − due to their antibacterial properties, although their environmental fate, metal release mechanisms, and the chemical state of the released Ag are far from defined . Hedberg et al explored interactions between Ag NPs of various surface charges and anionic, cationic, and nonionic surfactants used for laundry to understand changes in speciation, both in and during transport from the washing machine.…”