Document Type: Research Article
Department of Chemical Technologies, Iranian Research Organization for Science and Technology (IROST), Tehran, Iran
Three new nanocomposite films of Chitosan/ Ag NPs / N-Nicontinyl phosphoric triamide, containing 3% Ag NPs and 0%, 5% and 10% phosphoric triamide were prepared and characterized by X-ray Powder Diffraction (XRD), Field Emission Scanning Electron Microscopy (FE-SEM) and Energy Dispersive X-ray Spectroscopy (EDS) analysis methods. The nanocomposite films were prepared using ultrasonic waves plus cross linking the chitosan part of biofilms as final process and the Ag NPs were synthesized according to the citrate reduction method. XRD graph of the three nanocomposites showed all the characteristic peaks of the phosphoric triamide, Ag NPs, and chitosan, indicating the fact that the preparing process has not made any changes in the phases of the nanocomposites components. All the SEM micrographs and EDS analysis results confirmed the desired structures. In vitro antibacterial activities of the nanocomposite were tested against two Gram-positive bacteria: Staphylococcus aureus (S. aureus), Bacillus cereus (B. cereus) and two Gram-negative bacteria: Escherichia coli (E. coli), Pseudomonas aeruginosa (P. aeruginosa) in Brain-Heart Infusion (BHI) medium. Results revealed that the nanocomposite films, containing the phosphoric triamide additive, have better antibacterial effects than the one without this compound. Also, the antibacterial activity of the biofilms depends on the dosage of the phosphoric triamide and increases by raising the percentage of the additive in the biofilms structure.