Bioprinting of piezoresistive organohydrogel networks for advanced real-time mechanosensing in engineered tissue models

Understanding biomechanics in 3D cell culture is key to advancing tissue engineering, yet integrating real-time sensing into soft tissues remains a challenge. We developed a stretchable, piezoresistive hydrogel by combining PEDOT:PSS with a polyvinyl alcohol–sodium alginate matrix, optimized for detecting mechanical stimuli. This conductive organohydrogel exhibited a linear strain response. It was co-printed with a muscle cell-laden bioink to fabricate complex tissue architectures, maintaining structural stability and supporting tissue maturation. The embedded conductive hydrogel functioned as a flexible strain sensor, capable of detecting both bulk and localized mechanical inputs, with high sensitivity (0.054 per unit strain) and a strain detection limit of approximately 3%. Sensor data enabled spatial mapping of mechanical forces, offering a new strategy for real-time mechanosensing in engineered tissues. This approach provides a novel solution for integrating soft, biocompatible sensors into living tissues for applications in biomechanics and regenerative medicine.