Multi-functional Hydrogel Constructed by the Supramolecular Assembly between Ultralong DNA Chains and Tea Polyphenols

As a biological polymeric material, deoxyribonucleic acid (DNA) possesses unique sequence programmability, structural predictability and functional designability. Recently, DNA hydrogel has been widely used in bioimaging, drug delivery, the separation of biological particle and the intervention of cell behavior. However, the materials with DNA as the sole module face the challenges of structural singleness and functional limitations. To explore more synthesis methods and functions of DNA hydrogel, researchers have introduced hybrid functional modules to develop new molecular assembly strategies. As natural polyphenols, tea polyphenols (TP) have been proven to have good antioxidant, antibacterial, antiviral and anti-tumor activities, which make TP potential for various biological applications. Previous studies have shown that stable hydrogen bonds can be formed between the phosphate groups of DNA and the phenolic hydroxyl groups of polyphenols. Herein, a TPDNA hydrogel based on ultralong DNA chains was synthesized by double rolling circle amplification strategy and the assembly of TP with DNA. The mass ratio of TP to DNA in TP-DNA hybrid hydrogels was optimized. [GRAPHICS] The results of scanning electron microscopy and rheological test showed that TP-DNA hydrogel possessed porous structure and shear thinning property. On the other hand, the experiments of nuclease resistance, biocompatibility, antibacterial activity and wound healing evaluation were performed to explore the effect of TP on the properties of DNA hydrogels. The results showed that TP not only delayed the degradation rate of DNA hydrogel under nuclease, but also endowed the hydrogel with good antibacterial activity. In a rat wound healing model, the TPDNA hydrogel was proven to significantly promote wound healing.