In situ bio-inspired fabrication of Ag nanoparticles on Matricaria chamomilla extract modified Cu-Al-Zn LDH as a beneficial antimicrobial agent

This current study is based upon a biogenic process for the eco-friendly fabrication of Ag NPs anchored Matricaria chamomilla L. extract- modified layered double hydroxide (Ag NPs/LDH-M.chamomilla) nanocomposite material. Firstly, the plant, aqueous extract of Matricaria chamomilla was coated on the surface of Cu-Zn-Al LDH using their inherent adhering ability, which was farther employed for the in situ sustainable reduction of Ag+ ions into Ag NPs. The polyphenolics of herb extract further acted as a natural capping agent for the prepared nanocomposite without requiring extra harmful reagents. The as -fabricated Ag NPs/LDH-M.chamomilla nanocomposite was morphologically and structurally examined by various analytical methods like FE-SEM, FT-IR, EDX, elemental mapping, XRD, and TEM. It has been shown that the Ag NPs with uniform size and shape were distributed homogeneously over the M. chamomilla extract modified LDH. The M. chamomilla constituted bioactive compounds act as green reductant, capping and stabilizer agents for the effective immobilization of Ag NPs on the LDH surface without obvious accumulation. Thereafter, their antimicrobial activity was assessed thoroughly against pathogenic strains of Gram positive (Staphylococcus aureus, Staphylococcus epidermidis) and Gram negative (Escherichia coli and Pseudomonas aeruginosa) employing agar disc diffusion technique. Furthermore, MBC (Minimum Bactericidal Concentration) and MIC (Minimum Inhibitory Concentration) were determined via micro -well dilution assay. This clean and environmentally -safe ligand-free approach has outstanding advantages including facile preparation, eco-friendliness, and free of harmful reducing agents.