Synthesis of bio-inspired Ag-Au nanocomposite and its anti-biofilm efficacy

In the present study, bio-inspired Ag-Au nanocomposite was synthesized using banana peel extract (BPE) powder. The Ag-Au nanocomposite was characterized using various techniques such as UV-vis spectrophotometry, transmission electron microscopy (TEM) attached with energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD). Efficiency of AuNPs, AgNPs and Ag-Au nanocomposite was tested for their antibacterial activity against Pseudomonas aeruginosa NCIM 2948. The Ag-Au nanocomposite exhibits enhanced antimicrobial activity over its monometallic counterparts. Anti-biofilm activity of AgNPs, AuNPs and Ag-Au nanocomposite against P. aeruginosa was evaluated on glass surfaces. The Ag-Au nanocomposite exhibited the highest biofilm reduction (70-80%) when compared with individual AgNPs and AuNPs. Effect of AuNPs, AgNPs and Ag-Au nanocomposite on biofilm formation was evaluated in 96 wells microtiter plates. The percentage of biofilm inhibition was sharply increased with increasing concentration of AuNPs, AgNPs and Ag-Au composite. However, Au-Ag nanocomposite showed the highest biofilm inhibition when compared with individual AuNPs and AgNPs. This synergistic anti-biofilm activity of Ag-Au nanocomposite has an importance in the development of novel therapeutics against multidrug-resistant bacterial biofilm.