Preparation Of Polyurethane/Polyvinyl Alcohol Composite Hydrogels With Inorganic Nanoparticles For Wound Dressing Application

Hydrogels are widely used in the wound dressing field because of their unique physical and chemical properties.However,the poor mechanical properties of hydrogels and their vulnerability to bacterial infections have limited their use in wound dressings.In this paper,polyurethane/polyvinyl alcohol(PU/PVA)hydrogel as the main research body,some functional inorganic particles are introduced into PU/PVA hydrogel to improve its performance for wound dressing.First,silver nanoparticles were introduced into PU/PVA hydrogels by chemical reduction method to prepare a series of PU/PVA/Ag composite hydrogels with different silver contents.The structure of the composite hydrogel was analyzed by FTIR,X-ray photoelectron spectroscopy(XPS)and scanning electron microscopy(SEM).At the same time,the mechanical properties,swelling degree,tribological properties,biocompatibility,and antibacterial properties of the composite hydrogel were characterized.The results showed that the PU/PVA/Ag composite hydrogel had a porous structure.The introduction of Ag improves the mechanical properties of PU/PVA hydrogels and also has excellent antibacterial properties.In addition,PU/PVA/Ag hydrogels have good biocompatibility,moderate friction properties and swelling ability,which meet the basic requirements of wound dressings.Secondly,the layered double hydroxide intercalated with enoxacin was introduced into the PU/PVA hydrogel to prepare a series of PU/PVA/LDH-Eno composite hydrogel with different LDH-Eno contents.The mechanical properties,equilibrium water content and drug release effects of the composite hydrogels were characterized.The results showed that the introduction of LDH-Eno improved the mechanical properties of PU/PVA hydrogels and also conferred sustained release of PU/PVA hydrogels.Although the introduction of LDH-Eno reduced the equilibrium water content of the PU/PVA hydrogel,the effect was not significant and the water content could be maintained above 80%.This shows that the hydrogel has better water retention and can provide wounds a wet environment.In conclusion,PU/PVA/LDH-Eno hydrogels have excellent mechanical properties,high water content,and the effect of sustained release antimicrobial agents.In summary,PU/PVA/Ag hydrogels have good mechanical properties and biocompatibility,high water content,moderate friction and swelling and excellent antibacterial properties.The mechanical properties of PU/PVA/LDH-Eno hydrogels are good,the water content is high and it has the effect of slow release of the antibacterial drug enoxacin.Therefore,both PU/PVA/Ag composite hydrogels and PU/PVA/LDH-Eno composite hydrogels can be candidates for wound dressings.