Single molecule dynamics studies have begun to use quantum probes. Single particle analysis using cryo-transmission electron microscopy has dramatically improved the resolution when studying protein structures and is shifting towards molecular motion observations. X-ray free-electron lasers are also being explored as routes for determining single molecule structures of biological entities. Here, we propose a new X-ray single molecule technology that allows observation of molecular internal motion over long time scales, ranging from milliseconds up to 103 seconds. Our method uses both low-dose monochromatic X-rays and nanocrystal labelling technology. During monochromatic X-ray diffraction experiments, the intensity of X-ray diffraction from moving single nanocrystals appears to blink because of Brownian motion in aqueous solutions. X-ray diffraction spots from moving nanocrystals were observed to cycle in and out of the Bragg condition. Consequently, the internal motions of a protein molecule labelled with nanocrystals could be extracted from the time trajectory using this diffracted X-ray blinking (DXB) approach. Finally, we succeeded in distinguishing the degree of fluctuation motions of an individual acetylcholine-binding protein (AChBP) interacting with acetylcholine (ACh) using a laboratory X-ray source.

Hydrogel actuators, comprising gels that convert external stimuli into mechanical motion for actuation, are attracting attention for their promising applications, such as in robotics. The driving force is the absorption or release of water or another solvent, which results in swelling and shrinking motions, leading in turn to more complex functionalities. However, practical hydrogel actuators that can be controlled locally, such as ones that allow local actuation around the joints in rigid‐bodied robots, do not exist. Herein, the driving target of a thermo‐responsive hydrogel, poly(N‐isopropyl acrylamide), is integrated with the stimulation module using a liquid metal. The stimulation module provides heat as an external stimulus to the hydrogel actuator. The motion of the actuator is triggered by the heat supplied by an ultrasoft hydrogel coil, with liquid metal surrounding the driving target. The heat generated by current flowing through the liquid metal changes the temperature only around the desired part of the actuator, which enables the electrical control of an individual part of the hydrogel actuator. The concept of integrating the driving target and stimulator is expected to facilitate functional movement of actuators and expand the range of potential applications of hydrogels.

We demonstrate a solid phase reaction approach to synthesise transfer-free graphene on an insulating substrate by controlling the C diffusion process. Metal assisted crystallization by annealing of a C thin film was carried out to synthesise transfer-free graphene, in the presence of a top metal oxide and metal layer. Without the metal oxide layer, a large amount of C atoms diffused to the top of the metal surface and hence the formation of only small graphene domains was observed on the underneath of the metal layer. Introducing the metal oxide layer at the top surface, C diffusion was reduced and consequently the thin C film was crystallized to form large area graphene at the metal-insulating substrate interface. The metal oxide or metal catalyst layer was removed after graphene formation and transfer-free graphene was obtained directly on the base substrate. This finding shows that the thin metal oxide layer is critical to synthesise graphene with better quality and continuous domain structures.

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The ORCID identification number(s) for the author(s) of this article can be found under https://doi.org/10.1002/admt.201900794.Many micro total analysis systems (microTAS) and lab-on-achip applications have been developed that provide various functions such as mixing, [1,2] heating, [3,4] separation, [5][6][7] and extraction. [8,9] These applications are crucial to point-of-care testing (POCT), especially in developing countries. [10] These