Small Methods最新文献

Radiofrequency (RF) heating is a new, less invasive alternative to invasive heating methods that use nanoparticles for tumour therapy. But pinpoint local heating is still hard. Molecular interactions form a hybrid structure with unique electrical characteristics that enable RF heating in this work, which explores RF heating in a biological cell (yeast)-2D FeS₂ system. Substantial processes have been uncovered via experimental investigations and density functional theory (DFT) computations. At 3 W and 50 MHz, RF heating reaches 54°C in 40 s, which is enough to kill yeast cells, while current-voltage measurements reveal ionic diode-like properties. Interactions between yeast lipid molecules and 2D FeS_k, as shown by density-functional theory calculations, cause an imbalance in the distribution of charges and the creation of polar, conductive channels. Insights into biological heating applications based on radio frequency (RF) technology are offered by this work, which lays forth a framework for investigating 2D material-biomolecule interactions.

Nanopore sensing is a rapid, label-free technique that enables single-molecule detection and is successfully applied to nucleic acid sequencing. Extending this technology to the detection and sequencing of peptides and proteins is a key area of interest. However, the complex structures and diverse charge distributions of peptides and proteins present challenges for extensive detection using existing nanopores. In this study, the focus is on the EXP2 nanopore derived from the malaria parasite Plasmodium falciparum to address these challenges. Previously, it is characterized wild-type EXP2 (WT-EXP2) nanopores and demonstrated their ability to detect polypeptides, although intrinsic electrical noise from the pore posed difficulties for accurate detection. To overcome these limitations, several EXP2 nanopore mutants are designed, including EXP2_ΔD231, EXP2_NC, and EXP2_NC ^K42D/S46F, to reduce electrical noise and improve peptide detection accuracy. The EXP2_ΔD231 mutant reduced electrical noise by more than 50% compared to WT-EXP2 and improved the discrimination accuracy of oligoarginine peptides. In addition, the EXP2_ΔD231 detected and discriminated eight different peptides, ranging in molecular weight from small to large, that are previously challenging to detect using a single nanopore type. These results suggest that engineered EXP2 nanopores could serve as effective tools for peptide and protein detection and sequencing, contributing to the broader application of nanopore technology in biochemical and clinical research.

Intelligent electronic skin aims to mimic, enhance, and even surpass the functions of biological skin, enabling artificial systems to sense environmental stimuli and interact more naturally with humans. In healthcare, intelligent electronic skin is revolutionizing diagnostics and personalized medicine by detecting early signs of diseases and programming exogenous stimuli for timely intervention and on-demand treatment. This review discusses latest progress in bioinspired intelligent electronic skin and its application in medicine and healthcare. First, strategies for the development of intelligent electronic skin to simulate or even surpass human skin are discussed, focusing on its basic characteristics, as well as sensing and regulating functions. Then, the applications of electronic skin in health monitoring and wearable therapies are discussed, illustrating its potential to provide early warning and on-demand treatment. Finally, the significance of electronic skin in bridging the gap between electronic and biological systems is emphasized and the challenges and future perspectives of intelligent electronic skin are summarized.

The discrimination of ethylene (C₂H₄) and ethane (C₂H₆) by the precise regulation of porous materials is important and challenging. In this work, the quasi-exclusion of C₂H₆ from C₂H₄ is realized through a facile polymer modification and shaping method of metal-organic framework ZnAtzPO₄ (Atz = 3-amino-1,2,4-triazole). The polymer (carboxymethyl cellulose, CMC) modification and shaping of ZnAtzPO₄@CMC result in pore contraction and particle size enlargement, which impedes the diffusion of larger C₂H₆ molecules and improves the kinetic separation of C₂H₄/C₂H₆. The C₂H₆ capacity decreases steeply from 1.63 (ZnAtzPO₄ powder) to 0.27 mmol g^-1 (ZnAtzPO₄@CMC), and the resulting C₂H₄/C₂H₆ uptake ratio increases from 1.38 to 6.67. Kinetic adsorption experiments confirm that ZnAtzPO₄@CMC presents a negligible C₂H₆ dynamic capacity and the diffusion difference between C₂H₄ and C₂H₆ is amplified significantly. The corresponding kinetic C₂H₄/C₂H₆ separation selectivity of ZnAtzPO₄@CMC increases from 13.06 (ZnAtzPO₄) to 34.67, superior to the most reported benchmark materials. Furthermore, ZnAtzPO₄@CMC exhibits excellent breakthrough performance for equimolar C₂H₄/C₂H₆ mixture separation. This study provides guidance to discriminate similar gases through polymer modification of MOFs.

DNA origami consists of a long scaffold strand and short staple strands that self-assemble into a target 2D or 3D shape. It is a widely used construct in nucleic acid nanotechnology, offering a cost-effective way to design and create diverse nanoscale shapes. With promising applications in areas such as nanofabrication, diagnostics, and therapeutics, DNA origami has become a key tool in the bionanotechnology field. Simulations of these structures can offer insight into their shape and function, thus speeding up and simplifying the design process. However, simulating these structures, often comprising thousands of base pairs, poses challenges due to their large size. OxDNA, a coarse-grained model specifically designed for DNA nanotechnology, offers powerful simulation capabilities. Its associated ecosystem of visualization and analysis tools can complement experimental work with in silico characterization. This tutorial provides a general approach to simulating DNA origami structures using the oxDNA ecosystem, tailored for experimentalists looking to integrate computational analysis into their design workflow.

With the growing global demand for renewable energy and the increasing scarcity of lithium resources, sodium-ion batteries have received extensive attention and research as a potential alternative. Among many cathode materials for sodium-ion batteries, polyanion materials are favored for their high operating voltage, stable cycling performance, and good safety. However, the low electronic conductivity and low energy density of polyanionic materials limit their potential for large-scale commercial applications. To overcome this challenge, various strategies have been explored to improve their electrochemical performance. Among them, fluorine doping has been proven to be an effective means. In this study, we have systematically explored the effects of trace fluorine doping and mass fluorine substitution on the structure, dynamics, and electrochemistry of polyanionic cathode materials for sodium-ion batteries and deeply analyzed their reaction mechanisms. The analysis results show that trace fluorine doping can effectively improve the electronic conductivity of the material, thus enhancing its electrochemical performance. A large amount of fluorine substitution can effectively improve the voltage plateau of the material, thus enhancing its energy density. However, the environmental and safety challenges associated with the introduction of fluorine should also be addressed. Overall, the introduction of fluorine in polyanionic cathode materials can further optimize the electronic structure and electrochemical performance, thus realizing the wide application of high-performance sodium-ion batteries and making them a competitive battery technology.

Sodium-ion batteries (SIBs) are emerging as a promising alternative to lithium-ion batteries, primarily due to their plentiful raw materials and cost-effectiveness. However, the use of traditional organic liquid electrolytes in sodium battery applications presents significant safety risks, prompting the investigation of solid electrolytes as a more viable solution. Despite their advantages, single solid electrolytes encounter challenges, including low conductivity of sodium ions at room temperature and incompatibility with electrode materials. To overcome these limitations, the researchers develop composite polymer solid electrolytes (CPSEs), which merge the strengths of high ionic conductivity of inorganic solid electrolytes and the flexibility of polymer solid electrolytes. CPSEs are usually composed of inorganic materials dispersed in the polymer matrix. The final performance of CPSEs can be further improved by optimizing the particle size, relative content, and form of inorganic fillers. CPSEs show great advantages in improving ionic conductivity and interface compatibility, making them an important direction for future solid-state sodium battery research. Therefore, this paper summarizes recent advancements in composite solid electrolytes, discusses the impact of their preparation processes on performance, and outlines potential future developments in sodium-ion solid-state batteries.

Spatially resolved transcriptomics (SRT) is poised to advance the understanding of cellular organization within complex tissues under various physiological and pathological conditions at unprecedented resolution. Despite the development of numerous computational tools that facilitate the automatic identification of statistically significant intra-/inter-slice patterns (like spatial domains), these methods typically operate in an unsupervised manner, without leveraging sample characteristics like physiological/pathological states. Here PASSAGE (Phenotype Associated Spatial Signature Analysis with Graph-based Embedding), a rationally-designed deep learning framework is presented for characterizing phenotype-associated signatures across multiple heterogeneous spatial slices effectively. In addition to its outstanding performance in systematic benchmarks, PASSAGE's unique capability in calling sophisticated signatures has been demonstrated in multiple real-world cases. The full package of PASSAGE is available at https://github.com/gao-lab/PASSAGE.

Relaxor ferroelectric (RFE) films represent promising candidates for high-performance energy storage applications for miniaturized electronic devices and power systems. However, achieving substantial energy storage performance always involves complex component or structural design. Herein, we employed a nanocomposite approach to obtain ultrahigh-efficiency and robust energy density in simple BaTiO₃-based lead-free films. Our lead-free composition of simple (1-x)BaTiO₃-xCeO₂ (0.0 ≤ x ≤ 0.5) contains only four elements (Ba, Ti, Ce and O). The incorporation of stiff and insulating CeO₂ nanocomposites within BaTiO₃ matrix could disrupt the long-range-ordered micrometer-size domains into short-range-ordered nanodomains. This disruption suppresses hysteresis and delays polarization of BaTiO₃ films. Combined with the enhanced breakdown strength, this formulation yielded an ultrahigh efficiency of ≈90% and a robust energy density of 45 ± 3 J cm^-3 at CeO₂ contents of x = 0.3 and 0.4. Meanwhile, these two films with x = 0.3 and 0.4 exhibit superior frequency (50 Hz to 2 kHz) and thermal stability (20 °C to 120 °C), demonstrating stable energy storage performance. The proposed strategy opens up a new avenue for designing high-performance nanocomposite films by incorporating stiff secondary phase embedded in BaTiO₃ or even linear SrTiO₃ dielectrics.

Thermal stability is of great significance for the next-generation two-dimensional (2D) non-volatile spintronic devices. Typically, as the temperature increases, the spin polarization of materials decreases rapidly following the Bloch 𝑇^3/2 law in low-temperature regions, resulting in a rapid decrease in the tunneling magnetoresistance (TMR) of the magnetic tunnel junction (MTJ). Owing to the thermal effects induced by current during the writing processes, even small temperature fluctuations can result in significant variations in the TMR of MTJs, hindering their practical applications. In this paper, all-van der Waals Fe₃GaTe₂/GaSe/Fe₃GaTe₂ (FGaT/GaSe/FGaT) MTJ devices are constructed, achieving a TMR ratio of 47% at low temperatures and 17% at room temperature. Importantly, the TMR ratio remains stable within a temperature range from 2 to 160 K, breaking the Bloch 𝑇^3/2 law. The temperature-independent TMR is highly related to the enhanced perpendicular magnetic anisotropy (PMA) with reduced dimensionality is demonstrated. This work paves a promising path to achieve high-performance, thermally stable 2D spintronic memory chips.