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Vanadium‐based materials are fascinating potential cathodes for high energy density Zn‐ion batteries (ZIBs), due to their high capacity arising from multi‐electron redox chemistry. Most vanadium‐based materials suffer from poor rate capability, however, owing to their low conductivity and large dimension. Here, we propose the application of V2C MXene (V2CTx), a conductive 2D nanomaterial, for achieving high energy density ZIBs with superior rate capability. Through an initial charging activation, the valence of surface vanadium in V2CTx cathode is raised significantly from V2+/V3+ to V4+/V5+, forming a nanoscale vanadium oxide (VOx) coating that effectively undergoes multi‐electron reactions, whereas the inner V‐C‐V 2D multi‐layers of V2CTx are intentionally preserved, providing abundant nanochannels with intrinsic high conductivity. Owing to the synergistic effects between the outer high‐valence VOx and inner conductive V‐C‐V, the activated V2CTx presents an ultrahigh rate performance, reaching 358 mAh g−1 at 30 A g−1, together with remarkable energy and power density (318 Wh kg−1/22.5 kW kg−1). The structural advantages of activated V2CTx are maintained after 2000 cycles, offering excellent stability with nearly 100% Coulombic efficiency. This work provides key insights into the design of high‐performance cathode materials for advanced ZIBs. [ABSTRACT FROM AUTHOR]

The interaction between the zinc finger transcription factor (ZF–TF) and a specific DNA sequence is characterized by energy landscape parameters such as the dissociation rate constant and binding free energy. Heavy metals, such as lead (Pb) and cadmium (Cd), disturb transcription processes by changing the DNA-binding affinities of ZF–TF. To investigate the interference of heavy-metal ions with DNA transcription, we determined the unbinding force between ZF–TF and DNA by atomic force microscopy (AFM). The results suggest that the binding affinity of this complex is stronger in Pb(II) solution than under normal conditions, while the binding affinity in Cd(II) solution is weaker than under normal conditions. Thus, ZF–TF is an important target for heavy metal poisoning. Gold (Au) has a high affinity with cysteine residues, and so, it effectively coordinates with ZF–TF. AFM was employed to detect the molecular interaction force between ZF–TF and DNA in an Au(I) environment. Data analysis demonstrated that Au(I) helps restore normal binding affinity. The measurement of the unbinding force enabled us to quantify the binding free energy in the dissociation process. Alterations of kinetic parameters, which describe the energy landscape, are associated with metal poisoning disease and can be used to screen drugs for heavy-metal induced disease. [ABSTRACT FROM AUTHOR]

We demonstrate the use of two different wavelength ranges of excitation light as inputs to remotely trigger the responses of the self-assembled DNA devices (D-OR). As an important feature of this device, the dependence of the readout fluorescent signals on the two external inputs, UV excitation for 1 min and/or near infrared irradiation (NIR) at 800 nmfs laser pulses, can mimic function of signal communication in OR logic gates. Their operations could be reset easily to its initial state. Furthermore, these DNA devices exhibit efficient cellular uptake, low cytotoxicity, and high bio-stability in different cell lines. They are considered as the first example of a photo-responsive DNA logic gate system, as well as a biocompatible, multi-wavelength excited system in response to UV and NIR. This is an important step to explore the concept of photo-responsive DNA-based systems as versatile tools in DNA computing, display devices, optical communication, and biology. [ABSTRACT FROM AUTHOR]

We designed a functional drug delivery system based solely on DNA. The whole system was built with only four DNA strands. Cyclization of DNA strands excluded the formation of byproducts. DNA aptamers were equipped to endow triangular DNA nanostructures with targeting ability. The homogeneity of materials enabled not only facile construction but also convenient loading of nucleic acid-based drugs with much ease. [ABSTRACT FROM AUTHOR]

Platinum-based anticancer drugs are a class of widely used agents in clinical cancer treatment. However, their efficacy was greatly limited by their severe side effects and the arising drug resistance. The selective activation of inert platinum-based drugs in the tumor site by light irradiation is able to reduce side effects, and the novel mechanism of action of photoactivatable platinum drugs might also conquer the resistance. In this review, the recent advances in the design of photoactivatable platinum-based drugs were summarized. The complexes are classified according to their mode of action, including photoreduction, photo-uncaging, and photodissociation. The rationale of drug design, dark stability, photoactivation process, cytotoxicity, and mechanism of action of typical photoactivatable platinum drugs were reviewed. Finally, the challenges and opportunities for designing more potent photoactivatable platinum drugs were discussed. [ABSTRACT FROM AUTHOR]

The charge properties of polyamide membranes play a crucial role in the selective ionic and molecular sieving processes. These polyamide membranes fabricated through interfacial polymerization normally exhibit a front surface enriched with carboxyl groups and a rear surface enriched with amine groups, rendering it with a Janus surface charge. However, this disparity in charge properties between the two surfaces has not been thoroughly investigated, despite its importance in understanding the membrane formation mechanism. In this study, polyethylenimine (PEI, M w = 70000 Da) and piperazine (PIP, M w = 86 Da), with distinct molecular size, were employed as aqueous monomers to react with trimesoyl chloride (TMC) at a support-free water hexane interface to synthesize polyamide nanofiltration membranes. The charge differences in the rear and front surface of PEI/TMC and PIP/TMC nanofiltration membrane was fully explored. The PEI/TMC membrane demonstrated a great charge disparity between the two surfaces with a negatively charged (isoelectric point = 5.62) front surface and a positively charged (isoelectric point = 9.59) rear surface. As a result, the rear surface exhibits a higher MgCl 2 rejection (95.6 %) than the front surface (88.9 %). In contrast, the PIP/TMC membrane exhibited a similar negative charge and salt rejections on both surfaces. Moreover, the rear surface of PEI/TMC membrane exhibited a great anti-fouling performance to positively charged lysozyme (FDR = 51.1 %, FRR = 88.8 %). This work provides valuable insights into the mechanisms of an interfacial polymerization process [Display omitted] • Polyamide nanofiltration membranes, synthesized from a larger aqueous monomer PEI, demonstrate enhanced Janus surface charge properties. • The rear surface of PEI/TMC membranes exhibit a higher MgCl 2 rejection (95.6 %) than the front surface (88.9 %). • The rear surface of PEI/TMC membranes demonstrate higher fouling resistance to positively charged foulants but is easily fouled by positively charged foulants. Polyamide nanofiltration membranes, synthesized from a larger aqueous monomer, demonstrate enhanced Janus surface charge properties characterized by a highly positive real surface and a negatively charged frontal surface. [ABSTRACT FROM AUTHOR]