The development of ultralow voltage high‐performance bioartificial muscles with large bending strain, fast response time, and excellent actuation durability is highly desirable for promising applications such as soft robotics, active biomedical devices, flexible haptic displays, and wearable electronics. Herein, a novel high‐performance low‐priced bioartificial muscle based on functional carboxylated bacterial cellulose (FCBC) and polypyrrole (PPy) nanoparticles is reported, exhibiting a large bending strain of 0.93%, long actuated bending durability (96% retention for 5 h) under an ultralow harmonic input of 0.5 V, broad frequency bandwidth up to 10 Hz, fast response time (≈4 s) in DC responses, high energy density (6.81 KJ m−3), and high power density (5.11 KW m−3), all of which mainly stem from its high surface area and porosity, large specific capacitance, tuned mechanical properties, and strong ionic interactions of cations and anions in ionic liquid with FCBC and PPy nanoparticles. More importantly, bioinspired applications such as the grapple robot, bionic medical stent, bionic flower, and wings‐vibrating have been realized. These successful demonstrations offer a viable means for developing high‐performance bioartificial muscles for next‐generation soft bioelectronics including bioinspired robotics, biomedical microdevices, and wearable electronics.

Although many medical microrobots have been developed for treating diseases, their designs have not been optimized for disease environments and their functionality and capabilities have been primarily demonstrated in vitro. In addition, the imaging of microrobots within blood vessels in deep tissues remains a challenge. Herein, a chitosan‐based biodegradable microrobot with optimized structural design and X‐ray imaging for targeted vessel chemoembolization is reported. The design of the microrobot takes into account its magnetizability and stackability in blood vessels. The microrobot is prepared through laser micromachining of a porous chitosan sheet, attachment of nanoparticles, and filling the pores with gelatin. The optimized microrobot is biocompatible, biodegradable, thrombogenic, magnetically targetable, and drug‐loadable, as demonstrated both in vitro and in a blood vessel phantom. X‐ray imaging of the gold nanoparticle‐attached microrobots compares well with using commercial iodinated contrast materials, thereby demonstrating their real‐time long‐term X‐ray imaging capability. The in vivo real‐time imaging and targeted vessel embolization of the microrobot are demonstrated in rat liver. The proposed microrobot overcomes the limitations of embolic microbeads currently used in targeted vessel chemoembolization (i.e., targeted vessel blocking and X‐ray visibility) and expands the capability of microrobots in advanced platforms for treating human diseases.

Flexible sensing technologies are an essential link to future on-site and real-time monitoring technologies and devices in diverse fields, including healthcare, environment, medicine, food safety, biology, and so on. Compared to rigid substrate-based detection, the flexible sensing technique, which relies on the materials with soft and flexible features, provides intimate contact with arbitrary surfaces for on-site detection, especially in resource-limited environments. It can omit complicated extraction of analytes of interest and tedious sample preparation steps prior to detection, which is not suitable for practical applications. In particular, they are of great and continuous interest in medical diagnostics since they can provide noninvasive and real-time insight into the physiological signals of the human body, which is vital for more accurate diagnosis or tailoring therapy to maintain optimal health. These flexible biosensors can save healthcare time and costs, eventually aiming for personalized precision medicine. [1] Among the various flexible biosensors, surface-enhanced Raman scattering (SERS) has attracted enormous research attention because it provides a noninvasive, label-free, and molecular specific route for the recognition of a wide range of molecules with superb sensitivity. In SERS, the enormous electromagnetic signal enhancement is induced by the plasmonic coupling effect at a few nanometer-sized small space between metal nanostructures, so called "hot-spots". [2] Important prerequisites for flexible sensors are that they should produce a uniform signal regardless of bending that accompanies on-body usage, as well as present high signal enhancement and be resilient to mechanical strains. Although, the curvature of a person's waist, wrist, and thigh differs, a wearable sensor should exhibit uniform detection efficacy. However, most of the earlier flexible SERS strategies have created hot-spots between metal nanostructures on the surface of their backbone and attempted to locate target molecules inside the electromagnetic field concentrated region. In this case, the distance between the nanostructures on the flexible sensor was changed by bending the flexible sensor. This variance severely deteriorates the signal uniformity of the SERS sensor since the magnitude of hot-spots is extremely dependent on the distance between the metal nanostructures. [3] Surface-enhanced Raman scattering (SERS) based flexible sensing technology has been considered an essential candidate for future diagnostics in diverse fields. To obtain a reliable signal from the flexible SERS sensor, signal reproducibility even when the substrates are bent is highly desirable because there are various curvatures in the practical applications. However, this remains challenging because the "hot-spots" were created between the individual nanostructures on the surface of the previous flexible SERS sensor. The distance between each nanostructure varied through the bending of the sensor, leading to an adverse effect on the unform ...