Sustainable One-Step Solid-State Synthesis of Antibacterially Active Silver Nanoparticles Using Mechanochemistry

Area of Science:

• Green Chemistry
• Nanotechnology
• Materials Science

Background:

• Silver nanoparticles (AgNPs) exhibit potent antimicrobial properties.
• Traditional synthesis methods often involve harsh chemicals and conditions.
• Plant-mediated synthesis offers a sustainable alternative for nanomaterial production.

Purpose of the Study:

• To explore a green mechanochemical approach for synthesizing silver nanoparticles (AgNPs).
• To investigate the influence of different plant extracts (Thymus serpyllum, Sambucus nigra, Thymus vulgaris) on AgNP synthesis.
• To evaluate the effect of plant-to-silver precursor ratios on AgNP characteristics and antibacterial activity.

Main Methods:

• Solid-state mechanochemical synthesis using planetary milling.
• Green synthesis employing three different plant extracts: Thymus serpyllum (SER), Sambucus nigra (SAM), and Thymus vulgaris (TYM).
• Characterization using X-ray diffraction (XRD), Atomic Absorption Spectrometry (AAS), and Transmission Electron Microscopy (TEM).

Main Results:

• Successful synthesis of AgNPs using SER, SAM, and TYM extracts.
• SER demonstrated the highest reducing efficiency, while TYM was the least effective.
• Increased plant material quantity enhanced AgNP stability and decreased crystallite size.
• AgNPs synthesized at 1:1 and 1:10 ratios exhibited bimodal size distribution.
• Significant antibacterial activity was observed only for AgNPs synthesized at the 1:1 ratio, with SER-derived AgNPs showing the highest efficacy.

Conclusions:

• Green mechanochemistry provides an efficient route for AgNP synthesis.
• Plant extract choice and concentration significantly impact AgNP properties and bioactivity.
• Mechanochemically synthesized AgNPs using SER show promising antibacterial potential.