Engineering cell instructive dna-nanocomposites for tissue engineering, bio-printing and regenerative medicine

Engineering complex tissues that can enhance native tissue functions holds enormous promise for treating diseased conditions resulting from injuries, aging and diseases. Considerable effort has recently been directed towards the development of hydrogels for 3D printing such complex tissues, as they can mimic the physical, chemical, and biological properties of most biological tissues. However, the utility of available hydrogel bioinks for controlling cellular responses is severely constrained due to limited control over structural stability, printability and suboptimal biocompatibility. Here we describe the design of a new family of nanoengineered DNA polymer-based bioink to control and pattern cell behavior, engineer complex tissue structures, as well as utilize this injectable formulation as a drug delivery platform. Precisely, the hydrogel was designed by combining two different type of networks: Type A is made of interconnections between neighboring DNA strands and Type B consists of ionic interactions between the discotic charged (negative surface charge and positive charge along the edges) silicate nanodisks (nSi) and the DNA backbone (Fig 1A). The nSi was introduced to increase viscosity of DNA hydrogel and improve their shear-thinning (B, C), printability (D), and allograft coating properties with enhanced adhesivity (F).