Flexible electronic skins (e-skins) play a very important role in the development of human-machine interaction and wearable devices. To fully mimic the functions of human skin, e-skins should be able to perceive multiple external stimuli (such as temperature, touch, and friction) and be resistant to injury. However, both objectives are highly challenging. The fabrication of multifunctional e-skins is difficult because of the complex lamination scheme and the integration of different sensors. The design of skin-like materials is hindered by the trade-off problem between flexibility, toughness, and selfhealing ability. Herein, flexible sodium methallyl sulfonate functionalized poly(thioctic acid) polymer chains are combined with rigid conductive polyaniline rods through ionic bonds to obtain a solvent-free polymer conductive gel. The conductive gel has a modulus similar to that of skin, and shows good flexibility, puncture-resistance, notch-insensitivity, and fast self-healing ability. Moreover, this conductive gel can convert changes in temperature and strain into electrical signal changes, thus leading to multifunctional sensing performance. Based on these superior properties, a flexible e-skin sensor is prepared, demonstrating its great potential in the wearable field and physiological signal detection.

Inspired by nature, innovative devices have been made to imitate the morphology and functions of natural red blood cells (RBCs). Here, we report a red blood cell-mimetic micromotor (RBCM), which was fabricated based on a layer-by-layer assembly method and precisely controlled by an external rotating uniform magnetic field. The main framework of the RBCM was constructed by the natural protein zein and finally camouflaged with the RBC membrane. Functional cargos such as Fe 3 O 4 nanoparticles and the chemotherapeutic agent doxorubicin were loaded within the wall part of the RBCM for tumor therapy. Due to the massive loading of Fe 3 O 4 nanoparticles, the RBCM can be precisely navigated by an external rotating uniform magnetic field and be used as a magnetic resonance imaging contrast agent for tumor imaging. The RBCM has been proven to be biocompatible, biodegradable, magnetically manipulated, and imageable, which are key requisites to take micromotors from the chalkboard to clinics. We expect the RBC-inspired biohybrid device to achieve wide potential applications.

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An ionic liquids-based ultrasound-assisted extraction (ILUAE) method was successfully developed for extracting shikimic acid from conifer needles. Eleven 1-alkyl-3-methylimidazolium ionic liquids with different cations and anions were investigated and 1-benzyl-3-methylimidazolium bromide solution was selected as the solvent. The conditions for ILUAE, including the ionic liquid concentration, ultrasound power, ultrasound time, and liquid-solid ratio, were optimized. The proposed method had good recovery (99.37%–100.11%) and reproducibility (RSD, n = 6; 3.6%). ILUAE was an efficient, rapid, and simple sample preparation technique that showed high reproducibility. Based on the results, a number of plant species, namely, Picea koraiensis, Picea meyeri, Pinus elliottii, and Pinus banksiana, were identified as among the best resources of shikimic acid.