Construction And Biological Properties Of Multifunctional Fluorescent DNA Hydrogel

DNA has arisen as a promising building material for the construction of new biological functional materials owing to its unique properties such as biocompatibility,biodegradability,sgelectivity,molecular recognition,nano size controllability,maneuverability and editability.DNA hydrogel not only preserves the characteristics of common hydrogels such as high water content and mechanical properties,but also possesses the biological functions derived from DNA.Therefore,it has been applied in an assortment of applications such as biosensors,drug delivery,immunotherapy,protein production,tissue engineering,cell culture,supercapacitor and recycling circuits.However,almost all current DNA hydrogel consists of DNA macromolecules as its only component,which may have limited applications.Herein,circular DNA and ssDNA were rationally designed,which allow for the elongation of DNA chain via an enzymatic polymerization as well as the formation of AgNCs onto DNA scaffolds.Based on RCA,we obtained the composite fluorescent DNA hydrogel by two step method.The morphology and mechanical properties of DNA hydrogel were characterized by SEM and rheology test.Unexpectedly,we found out that how the secondary primers(ssDNA)were added was the key determinant for the formation of DNA hydrogel.And we explored the biological properties of composite fluorescent DNA hydrogels by antibacterial test,MTT test and doxorubicin hydrochloride sustained release test.The resultant hybrid DNA hydrogel not only shows distinctive morphology and mechanical properties,but also exhibits fluorescent and antibacterial functions.These characteristics,along with its biocompatibility,will allow the hydrogel to be suitable for a variety of potential biomedical applications such as tissue engineering,wound dressing and biosensing.