Flexible pressure sensors that can robustly mimic the function of slow-adapting type I (SA-I) mechanoreceptors are essential for realizing human-like object manipulation in artificial intelligent (AI) robots or amputees. Here, we report a straightforward approach to highly sensitive and robust flexible pressure sensors with fast response time and low operating voltage based on conductive micropyramids made of polydimethylsiloxane/carbon nanotube composites. Both numerical simulations and experimental studies show that the pressure-sensing properties of the devices can be systematically tuned by the spatial arrangement of micropyramids.
View Article and Find Full Text PDFA fundamental understanding of the charge transport mechanism in two-dimensional semiconductors (e.g., MoS) is crucial for fully exploring their potential in electronic and optoelectronic devices.
View Article and Find Full Text PDFThe preparation of alkyl chain-grafted poly(l-lysine) (PLL) vesicles with tunable molecular assembly in aqueous solution and the evaluation of their membrane permeability by drug release experiments have been investigated. Upon grafting long alkyl chains, polypeptides confined in the assembled nanostructures adopted ordered conformations such as α-helices or β-sheets/turns, leading to the dense packing of membranes and, consequently, the decreases in vesicular size and membrane permeability. The vesicles can also be cross-linked by genipin to form stable structures with tunable membrane permeability.
View Article and Find Full Text PDFThe fibrillation of hen egg-white lysozyme (HEWL) in the absence and presence of simple, unstructured D,L-lysine-co-glycine (D,L-Lys-co-gly) and D,L-lysine-co-L-phenylalanine (D,L-Lys-co-Phe) copolypeptides was studied by using a variety of analytical techniques. The attenuating and decelerating effects on fibrillation are significantly dependent on the polypeptide concentration and the composition ratios in the polypeptide chain. Interestingly, D,L-Lys-co-gly and D,L-Lys-co-Phe copolypeptides with the same composition ratio have comparable attenuating effects on fibrillation.
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