3D-Nanomaterials Printing for Tailorable Sensing and Flexible Electronics

Over the past decade, three-dimensional (3D) printing technology has fundamentally transformed traditional fabrication and manufacturing, particularly for micro-scale structures, models, and devices. Recent advancements in 3D printing, especially in the domain of nanomaterials, offer benefits such as ease of operation, cost-effectiveness, rapid prototyping, high resolution, and the capability to tailor designs and fabricate sensors customized to specific model requirements, individual needs, or disease diagnostics. Notably, with the rising emphasis on in-situ real-time health monitoring, the demand for wearable sensors is surging. However, to achieve widespread adoption of wearable biosensors for large-scale population monitoring, there's a need for swift, reliable, cost-effective, and high-throughput integration of these platforms.<br/><br/>In this study, we demonstrate our innovative approach to 3D printing of nanomaterials, successfully producing multiplexed, cost-effective, and mechanically flexible wearable bioelectronic sensing patches. These patches comprise 3D-printed nanomaterial-based flexible sensors and flexible wearable microfluidic sample-handling units, all integrated within just a few hours.<br/><br/>Further, we demonstrated the mechanical and electrical robustness of these patches under repeated bending cycles. We characterized the performance of the sensing units ex situ with various target ion samples across a spectrum of concentrations. Negative control experiments further showcased the patches' capability for selective ion detection. Additionally, we highlighted the potential of our 3D-printed nanomaterial patches for continuous health monitoring. This was evidenced by the simultaneous in situ monitoring of multiple ions (e.g., H+, Na+, K+, and Ca2+) present in sweat.<br/><br/>Our work represents a significant stride towards enabling personalized health monitoring practices, deploying 3D nanomaterial printing technology for the facile and affordable development of tailored, integrated wearable, and flexible biosensing platforms, optimized for the noninvasive and continuous monitoring of individual health parameters.