Electrochromic DNA-based bioink with rapid interfacial gelation for bioprinting applications

Recent advances in biofabrication demand bioinks that are not only biocompatible and mechanically suitable for tissue engineering, but also responsive to dynamic biological and electrical cues. Here, we introduce a DNA-viologen hybrid bioink system that rapidly forms a structurally defined hydrogel through interfacial gelation, enabling precise spatial control of gelation without requiring external triggers. The resulting hydrogel exhibits a hollow capsule morphology, tunable viscoelasticity, and excellent printability, making it suitable for soft tissue-direct patterning applications. Beyond its mechanical properties, this system integrates reversible electrochromic functionality, allowing dynamic optical responses under electrical stimulation. Taken together, this proof-of-concept study highlights how the integration of electroactive behavior with the programmability of DNA can open opportunities for multifunctional soft materials. The combination of rapid formation, structural adaptability, and electrical responsiveness underscores its promise in emerging applications, including wearable devices, biosensors, and stimuli-responsive platforms.