Electronics based on hydrogels can have inherent similarities to biological tissue and are of potential use in biomedical applications. Ideally, such hydrogel electronics should offer customizable three-dimensional circuits, but making complex three-dimensional circuits encapsulated within a hydrogel matrix is challenging with existing materials and manufacturing methods. Here we report the three-dimensional printing of hydrogel electronics using a curable hydrogel-based supporting matrix and a stretchable silver–hydrogel ink. The supporting matrix has a yield stress fluid behaviour, so the shear force generated by a moving printer nozzle creates a temporary fluid-like state, allowing the accurate placement in the matrix of silver–hydrogel ink circuits and electronic components. After printing, the entire matrix and embedded circuitry can be cured at 60 °C to form soft (Young’s modulus of less than 5 kPa) and stretchable (elongation of around 18) monolithic hydrogel electronics, whereas the conductive ink exhibits a high conductivity of around 1.4 × 10³S cm⁻¹. We use our three-dimensional printing approach to create strain sensors, inductors and biological electrodes.

基于水凝胶的电子产品与生物组织具有内在的相似性，在生物医学应用中具有潜在用途。理想情况下，这种水凝胶电子产品应提供可定制的三维电路，但将复杂的三维电路封装在水凝胶基质中对现有材料和制造方法具有挑战性。在这里，我们报告了使用基于可固化水凝胶的支撑基质和可拉伸银水凝胶墨水的水凝胶电子器件的三维打印。支撑基质具有屈服应力流体行为，因此移动打印机喷嘴产生的剪切力会产生暂时的流体状状态，从而可以在银水凝胶墨水电路和电子元件的基质中准确放置。打印后，³厘米^-1。我们使用我们的三维打印方法来创建应变传感器、电感器和生物电极。