Construction of cellulose/nanosilver sponge materials and their antibacterial activities for infected wounds healing

Antibacterial sponges with the silver nanoparticles (Ag NPs) were constructed by freeze-drying of cellulose composite hydrogels, which were prepared in NaOH/urea aqueous system with cooling, where the interconnecting pores of the sponge not only were used as micro-reactors to synthesize Ag nanoparticles but also inhibited the aggregation of Ag NPs. The Ag nanoparticles with size range from 4 to 50 nm, depending on the AgNO3 concentration, were uniformly immobilized in the cellulose/nanosilver sponges. The cellulose/nanosilver composite materials exhibited excellent antibacterial activities. Further, in vivo tests confirmed that the composite sponges had an ability to accelerate infected wound healing, as a result of the existence of the antibacterial Ag nanoparticles and absorbing capacity for wound exudate. The experimental data strongly encouraged the use of cellulose/nanosilver composite sponge as antibacterial materials, especially in case of serious wound infection. The composite cellulose sponge containing Ag nanoparticles provided an alternative material for the application of the infected wound healing.