Printable and flexible integrated sensing systems for wireless healthcare.

The rapid development of wearable sensing devices and artificial intelligence has enabled portable and wireless tracking of human health, fulfilling the promise of digitalized healthcare applications. To achieve versatile design and integration of multi-functional modules including sensors and data transmission units onto various flexible platforms, printable technologies emerged as some of the most promising strategies. This review first introduces the commonly utilized printing technologies, followed by discussion of the printable ink formulations and flexible substrates to ensure reliable device fabrication and system integration. The advances of printable sensors for body status monitoring are then discussed. Moreover, the integration of wireless data transmission via printable approaches is also presented. Finally, the challenges in achieving printable sensing devices and wireless integrated systems with competitive performances are considered, so as to realize their practical applications for personalized healthcare.

A monolithically integrated in-textile wristband for wireless epidermal biosensing.

Textile bioelectronics that allow comfortable epidermal contact hold great promise in noninvasive biosensing. However, their applications are limited mainly because of the large intrinsic electrical resistance and low compatibility for electronics integration. We report an integrated wristband that consists of multifunctional modules in a single piece of textile to realize wireless epidermal biosensing. The in-textile metallic patterning and reliable interconnect encapsulation contribute to the excellent electrical conductivity, mechanical robustness, and waterproofness that are competitive with conventional flexible devices. Moreover, the well-maintained porous textile architectures deliver air permeability of 79 mm s-1 and moisture permeability of 270 g m-2 day-1, which are more than one order of magnitude higher than medical tapes, thus ensuring superior wearing comfort. The integrated in-textile wristband performed continuous sweat potassium monitoring in the range of 0.3 to 40 mM with long-term stability, demonstrating its great potential for wearable fitness monitoring and point-of-care testing.