www.advmat.de www.advancedsciencenews.com Such soft wearable devices will be lightweight and thin, soft, and elastic, inexpensive, and durable. These devices will be skinattachable, flexible, stretchable, bendable and twistable whilst maintaining excellent sensing performances. Such disruptive WT products will ultimately transform current rigid wearable 1.0 to future wearable 2.0 products (Figure 1), enabling sensitive, accurate yet specific health monitoring anytime and anywhere.While the disruptive soft WT is still in the embryonic stage of development, there have been intensive worldwide materials [1c,8] push with a purpose to develop thinner, softer, ideally invisible and unfeelable electronics. [9] Unlike wearable 1.0 which typically starts from device, wearable 2.0 requires the design starts from materials innovation. In this context, novel structural design and the use of novel materials are the two viable strategies. [1b,10] For the former, serpentine design and prestrained treatment enable the stretchabilities; [11] as for the later, various nanomaterials including silver nanowires, [12] gold nanowires, [13] carbon nanotubes, [14] and graphene [15] have been widely explored.A typical soft WT research covers comprehensively all the key components in progressive sequences, namely, wear → sense → communicate → analyze → interpret → decide (Figure 2). This requires multidisciplinary collaborations across interdisciplinary boundaries. As a starting point, wearable materials should be designed to consider factors such as in soft/hard material interface, breathability, biocompatibility, etc. Then wearable sensors may be fabricated and evaluated with regards to key parameters including sensitivity, specificity, reusability, and durability. Once the sensors' performances have been fully evaluated, their integration with wireless modules such as Bluetooth Low Energy (BLE) or wireless fidelity (WIFI) needs to be considered. One of key limitations is the wearable powering solution. It is encouraging to see the commercial products of paper lithium battery and development of soft energy devices in academia. [16] In addition to hardware, designing user-friendly graphical user interfaces (GUIs) is necessary and the development of suitable apps is important for seamless data acquisition of timelapsed biometric signals in a wireless manner. The signals will be then analyzed and interpreted, enabling efficient algorithm for rapid signal processing and decision support. The analysis of electrical signals will help understand and predict the relationship between biometric data and sensing signals generated by soft wearable materials. This will allow us to understand the key parameters related to biological conditions such as cardiac health, [17] sporting activities, [18] and aged care behaviors. [19] Here, we discuss all of the above key aspects of next-generation of disruptive soft wearable technologies but with a focus on materials aspect. Nevertheless, it also emphasizes the significance of cross-disciplinary colla...

Development of high-performance fiber-shaped wearable sensors is of great significance for next-generation smart textiles for real-time and out-of-clinic health monitoring. The previous focus has been mainly on monitoring physical parameters such as pressure and strains associated with human activities. Development of an enzyme-based non-invasive wearable electrochemical sensor to monitor biochemical vital signs of health such as the glucose level in sweat has attracted increasing attention recently, due to the unmet clinical needs for the diabetic patients. To achieve this, the key challenge lies in the design of a highly stretchable fiber with high conductivity, facile enzyme immobilization, and straininsensitive properties. Herein, we demonstrate an elastic gold fiberbased three-electrode electrochemical platform that can meet the aforementioned criteria toward wearable textile glucose biosensing. The gold fiber could be functionalized with Prussian blue and glucose oxidase to obtain the working electrode and modified by Ag/AgCl to serve as the reference electrode; and the nonmodified gold fiber could serve as the counter electrode. The as-fabricated textile glucose biosensors achieved a linear range of 0−500 μM and a sensitivity of 11.7 μA mM −1 cm −2 . Importantly, such sensing performance could be maintained even under a large strain of 200%, indicating the potential applications in real-world wearable biochemical diagnostics from human sweat.

We have recently demonstrated that vertically aligned gold nanowires (v-AuNWs) are outstanding material candidates for wearable biomedical sensors toward real-time and noninvasive health monitoring because of their excellent tunable electrical conductivity, biocompatibility, chemical inertness, and wide electrochemical window. Here, we show that v-AuNWs could also be used to design a high-performance wearable pressure sensor when combined with rational structural engineering such as pyramid microarray-based hierarchical structures. The as-fabricated pressure sensor featured a low operation voltage of 0.1 V, high sensitivity in a low-pressure regime, a fast response time of <10 ms, and high durability with stable signals for the 10 000 cycling test. In conjunction with printed electrode arrays, we could generate a multiaxial map for spatial pressure detection. Furthermore, our flexible pressure sensor could be seamlessly connected with a Bluetooth low-energy module to detect high-quality artery pulses in a wireless manner. Our solution-based gold coating strategy offers the benefit of conformal coating of nanowires onto three-dimensional microstructured elastomeric substrates under ambient conditions, indicating promising applications in next-generation wearable biodiagnostics.