Si Sun

DNA nanotechnology has created a wide variety of nanostructures that provide a reliable platform for nanofabrication and DNA computing. However, constructing programmable finite arrays that allow for easy pre-functionalization remains challenge. We aim to create more standardized and controllable DNA origami components, which could be assembled into finite-scale and more diverse superstructures driven by instruction sets. In this work, we designed and implemented DNA origami building block pieces (DOBPs) with eight mutually independent programmable edges and formulated DNA instructions that tailored such components. This system enables DOBPs to be assembled into one or more specific 2D arrays according to the instruction sets. Theoretically, a two-unit system can generate up to 48 distinct DNA arrays. Importantly, experiments results demonstrated that DOBPs are capable of both deterministic and nondeterministic assemblies. Moreover, after examining the effects of different connection strategies and instruction implementations on the yield of the target structures, we assembled more complex 2D arrays, including limited self-assembly arrays such as ‘square frames’, ‘windmills’ and ‘multiples of 3’ long strips. We also demonstrated examples of Boolean logic gates ‘AND’ and ‘XOR’ computations based on these assembly arrays. The assembly system provides a model nano-structure for the research on controllable finite self-assembly and offers a more integrated approach for the storage and processing of molecular information.

Animal oils would not only pollute the water but also block the sewer. Using hydrophilic membrane is an effective approach for oil/water separation. However, abrasion would cause the damage of the membrane and shorten their service life. In this work, we prepared a sandwich structured oil/water separation membrane (SSM) with two layers of cotton fabric and a core layer of PAM modified stainless‐steel mesh via a cost‐effective and facile process. The as‐prepared membrane can selectively separate water from oil/water mixtures with high efficiency, high flux (beyond 6000 L m⁻² h⁻¹), and good reusability. Moreover, as compared with hydrogel coated mesh, the SSM exhibited good abrasion resistance, which would effectively improve the usability in real scenarios. More importantly, the SSM has successfully blocked the oil in a simulated sewer and a real sewer in the kitchen, which will help prevent sewer blockage.

Artificial muscles with large strokes are of special interest in diverse fields. However, it is difficult for large-diameter muscles to be rapidly cycled. In this study, hair artificial muscles with extremely large tensile stroke and fast recovery were prepared simply by twist insertion, coiling and steaming. The maximum tensile stroke for the hair artificial muscles upon water actuation was as large as 10000% and the large-stroke muscles could recover fast in ethanol. With a diameter of 7 mm and a twist density of 2500 turns m ^-1 , the compacted heterochiral hair artificial muscle could elongate 100 times of its original length in water and returned to its initial length in ethanol within 10 s. In addition, these hair artificial muscles maintained their excellent performance after either 100 water-ethanol stimulation cycles or staying in open air for 5 months. Moreover, the hair artificial muscle was able to contract by 59% when lifting 10 times its own weight, pull a wheel model or climb a long distance under water and work as a smart water-sensitive switch. This work demonstrates a facile and green strategy to prepare advanced natural fiber-based artificial muscles that have promising applications in soft robotics and biomedical engineering. Corresponding author(s) Email: sunsi@gzhu.edu.cn (Dr. Si Sun), qiangxl@gzhu.edu.cn (Dr. Xiao-Li Qiang), & xlshi@gzhu.edu.cn (Dr. Xiao-Long Shi)