Farzaneh Ghaemi - Lab of Polymer Synthesis, Faculty of Science, University of Zanjan, Zanjan, Iran
Maryam Khaleghi - Bioprocess Engineering Department, Institute of Industrial and Environmental Biotechnology, National Institute of Genetic Engineering and Biotechnology, Tehran, Iran
Fakhri Haghi - Department of Microbiology, School of Medicine, Zanjan University of Medical Sciences, Zanjan, Iran
Sohrab Rahmani - Lab of Polymer Synthesis, Faculty of Science, University of Zanjan, Zanjan, Iran

Introduction and Objectives: The medical researchers have paid considerable attention to wound as a serious dilemma in sores or burn wounds. The aim of this study was to synthesis a novel Nano-composite hydrogel via click reaction chemistry followed by introducing of silver nanoparticles (Ag-NPs). Material and Methods: Dialkynyl PEG was synthesized using PEG-2000 in the presence of NaH and propargyl bromide. Then, 2,2-bis(azidomethyl) 1,3-propane diol was synthesized using 2,2-bis(bromomethyl) 1,3-propane diol in the presence of NaN3. Finally, polyurethane with pendant azido groups was synthesized using hexamethylene diisocyanate, dialkynyl PEG and 2,2-bis(azidomethyl) 1,3-propane diol in the presence of dibuthyl tin dilorate catalyst in THF solvent. Thereafter, Hydrogel was synthesized via coupling reaction between azide and alkyne groups of prepolymers in the presence of CuSO4.5H2O and sodium ascorbate catalyst system. Green synthesis of the Ag-NPs was performed using oak fruit hull (Jaft) extract and then the NPs with concentrations (100, 200, 400 or 800 ppm) were loaded in the hydrogel. Various analysis methods such as NMR and FTIR spectroscopy, FE-SEM and XRD were used for characterization of hydrogel silver nano-composite. Finally, antibacterial activity of the silver nano-composite hydrogel was investigated against Psudomonas aeruginosa PAO1 and Staphylococcus aureus ATCC 13565 using disk diffusion and macrobroth dilution methods. Results: FTIR and NMR analysis showed that the prepolymers and hydrogel were synthesized successfully. FE-SEM revealed the porous microstructure of the hydrogel. XRD results showed the crystallinity of the Ag-NPs. According to disk diffusion test on Mueller Hinton agar, 10 mm and 12mm inhibition zone around the Ag-loaded hydrogels was observed against P. aeruginosa and S. aureus, respectively. Also, minimum inhibitory concentration (MIC) of Nano-composite hydrogel against P. aeruginosa and S. aureus in macrobroth dilution was in NPs concentration of 200 ppm. Conclusion: Based on these data, our PU-PEG based Nano-silver composite hydrogel can be used in the field of wound dressing or burn related infections management.

Green synthesis, Silver Nano-composite, Antibacterial hydrogel