Ion transporters

Heavy metal pollution is a global environmental problem, and Quercus variabilis has a stronger tolerance to Cd stress than do other species. We aimed to explore the physiological response and molecular mechanisms of Q. variabilis to Cd stress. In this study, the antioxidant enzyme activities of leaves were determined, while the photosynthetic parameters of leaves were measured using Handy PEA, and ion fluxes and DEGs in the roots were investigated using noninvasive microtest technology (NMT) and RNA sequencing techniques, respectively...

The application of composite solid electrolytes (CSEs) in solid-state lithium-metal batteries is limited by the unsatisfactory ionic conductivity underpinned by the low concentration of free lithium ions. Herein, we propose an interface design strategy where an amine silane linker is employed as a coupling agent to graft the Li7 La3 Zr2 O12 (LLZO) ceramic nanofibers to the poly(vinylidene fluoride- co -hexafluoropropylene) (PVDF-HFP) polymer matrix to enhance their interaction. The hydrogen bonding between amino-functionalized LLZO (NH2 @LLZO) and PVDF-HFP not only effectively induces a uniform incorporation of high-content nanofibers (50 wt %) into the polymer matrix but also furnishes sufficient continuous surfaces to weaken the complexation between PVDF-HFP and Li-ion carriers...

Expanding the interlayer spacing plays a significant role in improving the conductivity of a cellulose-based conductor. However, it remains a challenge to regulate the cellulose nanochannel expanded by ion coordination. Herein, starting from multiscale mechanics, we proposed a strain engineering method to regulate the interlayer spacing of the cellulose nanochannels. First-principles calculations were conducted to select the most suitable ions for coordination. Large-scale molecular dynamics simulations were performed to reveal the mechanism of interlayer spacing expansion by the ion cross-linking...

In contrast to biological cell membranes, it is still a major challenge for synthetic membranes to efficiently separate ions and small molecules, due to their similar sizes in the sub-nanometer range. Inspired by biological ion channels with their unique channel wall chemistry that facilitates ion sieving by ion-channel interactions, we report here the first free-standing, ultrathin (10-17 nm) nanomembranes composed entirely of polydopamine (PDA) as ion and molecular sieves. These nanomembranes are obtained via an easily scalable electropolymerization strategy and provide nanochannels with various amine and phenolic hydroxyl groups that offer a favorable chemical environment for ion-channel electrostatic and hydrogen bond interactions...

We investigated the magnetocaloric and electrical transport properties of the Eu8 CuNi2.5 Si42.5 clathrate compound, synthesized by an arc melting and annealing method. X-ray photoemission spectroscopy revealed a mixed valence state of Eu2+ and Eu3+ . The low-field and low-temperature magnetic measurements indicated a multiple magnetic transition, from ferromagnetic near 35 K to antiferromagnetic at 25 K. Increasing the magnetic field led to the broadening of antiferromagnetic peaks and a final ferromagnetic state under high magnetic fields, indicative of spin reorientation...

Zinc-ion batteries are promising candidates for large-scale energy storage, and gel polymer electrolytes (GPEs) play an important role in zinc-ion battery applications. Metal-organic frameworks (MOFs) are characterized by large specific surface areas and ordered pores. This highly ordered microporous structure provides a continuous transport channel for ions, thus realizing the high-speed transmission of ions. In this paper, an MOF-modified dendrite-free GPE was designed. The incorporation of MOF particles not only reduces the crystallinity of the polymer, increases the motility of the molecular chains, and facilitates the transfer of Zn2+ , but also attracts anions to reduce polarization during electrochemical reactions...

Lithium cobalt oxide (LiCoO2 ) is considered as one of the promising building blocks that can be used to fabricate all-solid-state thin film batteries (TFBs) because of its easy accessibility, high working voltage, and high energy density. However, the slow interfacial dynamics between LiCoO2 and LiPON in these TFBs results in undesirable side reactions and severe degradation of cycling and rate performance. Herein, amorphous vanadium pentoxide (V2 O5 ) film was employed as the interfacial layer of a cathode-electrolyte solid-solid interface to fabricate all-solid-state TFBs using a magnetron sputtering method...

Nanoplastics pollution has emerged as a global issue due to its widespread potential toxicity. This study delved in to toxic effects of nanoplastics on juvenile P. clarkii and molecular mechanisms from perspectives of growth, biochemical, histopathological analysis and transcriptome level for the first time. The findings of this study indicated that nanoplastics of different concentrations have varying influence mechanisms on juvenile P. clarkii. Nanoplastics have inhibitory effects on growth of juvenile P...

Mass spectrometry has been increasingly explored in intraoperative studies as a potential technology to help guide surgical decision making. Yet, intraoperative experiments using high-performance mass spectrometry instrumentation present a unique set of operational challenges. For example, standard operating rooms are often not equipped with the electrical requirements to power a commercial mass spectrometer and are not designed to accommodate their permanent installation. These obstacles can impact progress and patient enrollment in intraoperative clinical studies because implementation of MS instrumentation becomes limited to specific operating rooms that have the required electrical connections and space...

Zinc and iron are two essential trace minerals that play a pivotal role in maintaining optimal health and well-being in the human body. Despite being required in relatively small quantities, their significance can be understated as they participate in a wide array of critical physiological processes such as oxygen transport, DNA synthesis, controlling nutrient availability, etc. Understanding the distribution and behavior of these ions in natural water bodies is essential for assessing water quality, studying ecological processes, and managing environmental impacts...

The endocrine system is an essential regulator of the osmoregulatory organs that enable euryhaline fishes to maintain hydromineral balance in a broad range of environmental salinities. Because branchial ionocytes are the primary site for the active exchange of Na+ , Cl- , and Ca2+ with the external environment, their functional regulation is inextricably linked with adaptive responses to changes in salinity. Here, we review the molecular-level processes that connect osmoregulatory hormones with branchial ion transport...

Band 3, or anion exchanger 1 (AE1), is one of the indispensable transmembrane proteins involved in the effective respiratory process of the human body and is primarily responsible for the exchange of bicarbonate and chloride anions across the plasma membrane of erythrocyte. However, the molecular mechanism of ion transport of Band 3 is not completely understood, yet. In this work, we systematically investigate the key binding sites of bicarbonate ions in Band 3 and the impact of cholesterol (CHOL) in lipid bilayers on bicarbonate ion binding using all-atom molecular dynamics (MD) simulations...

The advancement of cell-mimic materials, which can forge sophisticated physicochemical dialogues with living cells, has unlocked a realm of intriguing prospects within the fields of synthetic biology and biomedical engineering. Inspired by the evolutionarily acquired ability of T lymphocytes to release perforin and generate transmembrane channels on targeted cells for killing, herein we present a pioneering DNA-encoded artificial T cell mimic model (ARTC) that accurately mimics T-cell-like behavior. ARTC responds to acidic conditions similar to those found in the tumor microenvironment and then selectively releases a G-rich DNA strand (LG4) embedded with C12 lipid and cholesterol molecules...

Cholesterol and calcium play crucial roles as integral structural components and functional signaling entities within the central nervous system. Disruption in cholesterol homeostasis has been linked to Alzheimer's, Parkinson's, and Huntington's Disease while alterations in calcium signaling is hypothesized to be a key substrate for neurodegeneration across many disorders. Despite the importance of regulated cholesterol and calcium homeostasis for brain health there has been an absence of research investigating the interdependence of these signaling molecules and how they can tune each other's abundance at membranes to influence membrane identity...

Strong correlations are often manifested by exotic electronic phases and phase transitions. LaCoO3-δ (LCO) is a system that exhibits such strong electronic correlations with lattice-spin-charge-orbital degrees of freedom. Here, we show that mesoscopic oxygen-deficient LCO films show resistive avalanches of about 2 orders of magnitude due to the metal-insulator transition (MIT) of the film at about 372 K for the 25 W RF power-deposited LCO film on the Si/SiO2 substrate. In bulk, this transition is otherwise gradual and occurs over a very large temperature range...

Cells exist in natural, dynamic microenvironmental niches that facilitate biological responses to external physicochemical cues such as mechanical and electrical stimuli. For excitable cells, exogenous electrical cues are of interest due to their ability to stimulate or regulate cellular behavior via cascade signaling involving ion channels, gap junctions, and integrin receptors across the membrane. In recent years, conductive biomaterials have been demonstrated to influence or record these electrosensitive biological processes whereby the primary design criterion is to achieve seamless cell-material integration...

Disruption of the symbiosis of extra/intratumoral metabolism is a good strategy for treating tumors that shuttle resources from the tumor microenvironment. Here, we report a precision treatment strategy for enhancing pyruvic acid and intratumoral acidosis to destroy tumoral metabolic symbiosis to eliminate tumors; this approach is based on PEGylated gold and lactate oxidase-modified aminated dendritic mesoporous silica with lonidamine and ferrous sulfide loading (PEG-Au@DMSNs/FeS/LND@LOX). In the tumor microenvironment, LOX oxidizes lactic acid to produce pyruvate, which represses tumor cell proliferation by inhibiting histone gene expression and induces ferroptosis by partial histone monoubiquitination...

Most biological functions have their basis in a rapid change in cell membrane permeability. Hodgkin and Huxley showed regulation of the flow of molecules and ions between the nerve cell and its environment (Nobel Prize 1963), by recording macroscopic currents. Two Germans Neher and Sakmann showed that specific ion channels actually exist, and specific membrane proteins act as gates or agents for active transport regulating in physiological and pathological processes.

Bacteria contain conserved mechanisms to control the intracellular levels of metal ions. Metalloregulatory transcription factors bind metal cations and play a central role in regulating gene expression of metal transporters. Often, these transcription factors regulate transcription by binding to a specific DNA sequence in the promoter region of target genes. Understanding the preferred DNA-binding sequence for transcriptional regulators can help uncover novel gene targets and provide insight into the biological role of the transcription factor in the host organism...

Ion-selective nanochannel membranes assembled from two-dimensional (2D) nanosheets hold immense promise for power conversion using salinity gradient. However, they face challenges stemming from insufficient surface charge density, which impairs both permselectivity and durability. Herein, we present a novel vacancy-engineered, oxygen-deficient NiCo layered double hydroxide (NiCoLDH)/cellulose nanofibers-wrapped carbon nanotubes (VOLDH/CNF-CNT) composite membrane. This membrane, featuring abundant angstrom-scale, cation-selective nanochannels, is designed and fabricated through a synergistic combination of vacancy engineering and interfacial super-assembly...