Technological watch

Advances in additive manufacturing are leading to the emergence of new printable applications, including sensors for healthcare monitoring and bio?engineering scaffolds. Research is driven by designing new printable inks including composites that can be extruded and respond to changes in their surroundings and patterning these materials on the micro?scale. In modern printing techniques, an emerging modified three?dimensional (3D) printing method: materials extrusion has been utilized for customizable electronics because of its high compatibility with various inks, low cost, and versatility to different levels of complexity. Material extrusion not only enables the printing of 2D and 3D architecture of the electrode structure but also bioprinting of structures such as conductive scaffolds. In this review, fundamental insights into rational printable ink formulation include colloidal suspensions, gels, polymer melts, composites, printing criteria, processes, and applications towards printable electronics using composites composed of nanomaterials and biopolymers are fully discussed. We present new manufacturing insights on how to further improve the resolution and simplify the printing process of responsive materials, which has not been seen in currently published representative reviews. We envision that this review provides high scientific merits to readers working in wearable devices, biological smart materials, and flexible nano?electronicsThis article is protected by copyright. All rights reserved.