Low-Temperature Sintering Inks for Printed Bioelectronics: Materials, Mechanisms, and Emerging Ideas

Printed electronics have emerged as a versatile manufacturing platform for next-generation biosensors, enabling on-demand and low-cost fabrication of functional devices on flexible, stretchable, and unconventional substrates. One major challenge in this field lies in the sintering of printed features, as conventional high-temperature processing is incompatible with polymeric substrates and thermally sensitive biological components. Low-temperature sintering inks, typically processed below 200 °C or even at room temperature, have become a critical enabling technology for bio-integrated electronics. This review provides an overview of the current state-of-the-art and key challenges associated with low-temperature sintering inks for printed bioelectronics. We discuss inks based on metal nanoparticles, metal-organic decomposition precursors, metal oxides, chalcogenides, and hybrid material systems. The emphasis is on how ink chemistry, ligand selection, and precursor structure govern rheology, stability, and sintering behavior. In addition, key low-temperature sintering and curing strategies, including thermal, photonic, laser, plasma, microwave, and chemical sintering, are compared in terms of energy delivery, densification mechanisms, and substrate compatibility. Finally, we outline emerging directions towards low temperature and room-temperature sintering inks, and sustainable biobased ink formulations, and discuss their applications for wearable, implantable, and soft biosensing platforms.