Nano-silver biological sponge and preparation method thereof

The invention discloses a nano-silver biological sponge and a preparation method thereof. The nano-silver biological sponge comprises a biological sponge which is made of a biological material and nano silvers which are evenly distributed in the biological sponge, wherein the biological material is any one or a combination of any two or more than two of chitosan, carboxymethyl chitosan, alginate, gelatin and collagen. The preparation method for the nano-silver biological sponge comprises the following steps: dissolving the biological material such as the chitosan and the like in a solvent, adding cross linker and silver nitrate solution into the solvent, and obtaining the nano-silver biological sponge through freeze drying, heating and curing, and ultraviolet ray or cobalt 60 irradiation. The nano-silver biological sponge has the characteristics of safety and no toxicity, good biocompatibility and biodegradability and remarkable antibacterial effect, and has certain functions of stanching and promoting healin