ACS Earth and Space Chemistry最新文献

The peripheral nervous system, consisting of somatic sensory circuits and autonomic effector circuits, enables communication between the body’s organs and the brain. Dysregulation in these circuits is implicated in an array of disorders and represents a potential target for neuromodulation therapies. In this Perspective, we discuss recent advances in the neurobiological understanding of these brain–body pathways and the expansion of neurotechnologies beyond the brain to the viscera. We focus primarily on the development of integrated technologies that leverage bioelectronic devices with optogenetic tools. We highlight the discovery and application of ultrapotent and red-shifted channelrhodopsins for minimally invasive optogenetics and as tools to study brain–body circuits. These innovations enable studies of freely behaving animals and have enhanced our understanding of the role physiological signals play in brain states and behavior.

Energy harvesting from ubiquitous natural water vapor based on moisture electric generator (MEG) technology holds great potential to power portable electronics, the Internet of Things, and wireless transmission. However, most devices still encounter challenges of low output, and a single MEG complemented with another form of energy harvesting for achieving high power has seldom been demonstrated. Herein, we report a flexible and efficient hybrid generator capable of harvesting moisture and tribo energies simultaneously, both from the source of water droplets. The moisture electric and triboelectric layers are based on a water-absorbent citric acid (CA)-mediated polyglutamic acid (PGA) hydrogel and porous electret expanded polytetrafluoroethylene (E-PTFE), respectively. Such a waterproof E-PTFE film not only enables efficient triboelectrification with water droplets' contact but also facilitates water vapor to be transferred into the hydrogel layer for moisture electricity generation. A single hybrid generator under water droplets' impact delivers a DC voltage of 0.55 V and a peak current density of 120 μA cm^–2 from the MEG, together with a simultaneous AC output voltage of 300 V and a current of 400 μA from the complementary water-based triboelectric generator (TEG) side. Such a hybrid generator can work even under harsh wild environments with 5 °C cold and saltwater impacts. Significantly, an optical alarm and wireless communication system for wild, complex, and emergency scenarios is demonstrated with power from the hybrid generators. This work expands the applications of water-based electricity generation technologies and provides insight into harvesting multiple potential energies in the natural environment with high output.

Cellular nanoparticles (CNPs), fabricated by coating natural cell membranes onto nanoparticle cores, have been widely used to replicate cellular functions for various therapeutic applications. Specifically, CNPs act as cell decoys, binding harmful molecules or infectious pathogens and neutralizing their bioactivity. This neutralization strategy leverages the target’s functional properties rather than its structure, resulting in broad-spectrum efficacy. Since their inception, CNP platforms have undergone significant advancements to enhance their neutralizing capabilities and efficiency. This review traces the research advances of CNP technology as multiplex countermeasures across four categories with progressive functions: neutralization through cell membrane binding, simultaneous neutralization using both cell membrane and nanoparticle core, continuous neutralization via enzymatic degradation, and enhanced neutralization through membrane modification. The review highlights the structure–property relationship in CNP designs, showing the functional advances of each category of CNP. By providing an overview of CNPs in multiplex neutralization of a wide range of chemical and biological threat agents, this article aims to inspire the development of more advanced CNP nanoformulations and uncover innovative applications to address unresolved medical challenges.

Silver chalcogenide (Ag₂X, X = S, Se, Te) semiconductor quantum dots (QDs) have been extensively studied owing to their short-wave infrared (SWIR, 900–2500 nm) excitation and emission along with lower solubility product constant and environmentally benign nature. However, their unsatisfactory photoluminescence quantum yields (PLQYs) make it difficult to obtain optoelectronic devices with high performances. To tackle this challenge, researchers have made great efforts to develop valid strategies to improve the PLQYs of SWIR Ag₂X QDs by suppressing their nonradiative recombination of excitons. In this Perspective, we summarize the significant approaches of heteroatom doping and surface passivation to enhance the PLQYs of SWIR Ag₂X QDs, and we conclude their application in high-efficiency optoelectronic devices. Finally, we examine the future trends and promising opportunities of Ag₂X QDs with regard to their optical properties and optoelectronics. We believe that this Perspective will serve as a valuable reference for future advancement in the synthesis and application of SWIR Ag₂X QDs.

Each organelle referring to a complex multiorder architecture executes respective biological processes via its distinct spatial organization and internal microenvironment. As the assembly of biomolecules is the structural basis of living cells, creating synthetic nanoassemblies with specific physicochemical and morphological properties in living cells to interfere or couple with the natural organelle architectures has attracted great attention in precision therapeutics of cancers. In this review, we give an overview of the latest advances in the synthetic nanoassemblies for precise organelle regulation, including the formation mechanisms, triggering strategies, and biomedical applications in precision therapeutics. We summarize the emerging material systems, including polymers, peptides, and deoxyribonucleic acids (DNAs), and their respective intermolecular interactions for intercellular synthetic nanoassemblies, and highlight their design principles in constructing precursors that assemble into synthetic nanoassemblies targeting specific organelles in the complex cellular environment. We further showcase the developed intracellular synthetic nanoassemblies targeting specific organelles including mitochondria, the endoplasmic reticulum, lysosome, Golgi apparatus, and nucleus and describe their underlying mechanisms for organelle regulation and precision therapeutics for cancer. Last, the essential challenges in this field and prospects for future precision therapeutics of synthetic nanoassemblies are discussed. This review should facilitate the rational design of organelle-targeting synthetic nanoassemblies and the comprehensive recognition of organelles by materials and contribute to the deep understanding and application of the synthetic nanoassemblies for precision therapeutics.

The magnetoelectric (ME) effect, which involves the interaction of magnetic and electric fields within a material, has a significant potential for various applications. Our study addresses the limitations of conventional magnetostriction-based ME materials by demonstrating an alternative approach that achieves substantial ME effects in core–shell-type nanocomposites at room temperature. By synthesizing ferrimagnetic Fe₃O₄ nanoparticles onto piezoelectric poly(vinylidene fluoride) (PVDF) particles, we identified a distinct ME mechanism. In magnetorheological (MR) fluids, the magnetic-field-induced aggregation of Fe₃O₄ nanoparticles, combined with the piezoelectricity of PVDF, leads to a pronounced ME effect, significantly enhancing the performance and stability of MR fluids. This research highlights a crucial observation of distinct ME effects, which could suggest potential pathways for advancements in practical applications including microfluidics, vibration dampers, tactile technologies, and biomedical and bioengineering fields.

Photocatalysis is a cost-effective approach to producing renewable energy. A thorough comprehension of carrier separation at the micronano level is crucial for enhancing the photochemical conversion capabilities of photocatalysts. However, the heterogeneity of photocatalyst nanoparticles and complex charge migration processes limit the profound understanding of photocatalytic reaction mechanisms. By establishing the precise interrelationship between microscopic properties and photophysical behaviors of photocatalysts, single-particle fluorescence spectroscopy can elucidate the carrier separation and catalytic mechanism of the photocatalysts in situ, which provides perspectives for improving the photocatalytic efficiency. This Review primarily focuses on the basic principles and advantages of single-particle fluorescence spectroscopy and its progress in the study of plasmonic and semiconductor photocatalysis, especially emphasizing its importance in understanding the charge separation and photocatalytic reaction mechanism, which offers scientific guidance for designing efficient photocatalytic systems. Finally, we summarize and forecast the future development prospects of single-particle fluorescence spectroscopy technology, especially the insights into its technological upgrading.

Two-dimensional (2D) borophene materials are predicted to be ideal catalytic materials due to their structural analogy to graphene. However, the lack of chemical functionalization of borophene hinders its practical application in catalysis. Herein, we reported a massive production of freestanding few-layer 2D borophene oxide (BO) sheets with tunable active oxygen species by a moderate oxidation-assisted exfoliation method. State-of-the-art characterizations demonstrated the evolution of active oxygen species from surface B–O species at the initial stage to the intermediate B_xO_y (1.5 < x/y < 3) species and eventually to bulk B₂O₃ with an increasing oxidation duration. As a result, the 2D BO sheet with enhanced B–O species exhibited a strikingly high catalytic activity for the aerobic oxidation of benzylamine into N-benzylidenebenzylamine. The formation rate of imine reaches as high as 29.7 mmol g_catal^–1 h^–1 under mild reaction conditions, higher than that of pristine borophene, boron oxides, graphene oxide, and other metal/metal-free catalysts in the reported literature. Density functional theory calculations further revealed the critical role of surface B–O species, which favor the adsorption and N–H activation of benzylamine for high activity and suppress the deep dehydrogenation, yielding an outstanding imine selectivity (>90%). This work paves the route for a moderate and scalable synthesis of few-layer BO sheets with highly active B–O species toward advanced metal-free catalysis beyond graphene.

Resistant starch (RS) is present in various natural and processed foods as well as medications. It has garnered significant attention from both scientists and consumers due to its notable health benefits. However, there is a limited understanding of how RS particles are absorbed at the cellular level and their metabolic behavior, resulting in a lack of clarity regarding the intestinal safety implications of prolonged RS exposure. Here, we demonstrate that rice-derived RS nanoparticles (RSNs) can lead to colitis in mice by triggering lysosomal exocytosis. The research shows that RSNs enter the cells through macropinocytosis and clathrin- and caveolin-mediated endocytosis and activate TRPML1 thereafter, causing the release of lysosomal calcium ions. This, in turn, triggered the TFEB signaling pathway and thus upregulated the lysosomal exocytosis level, leading to lysosomal enzymes to be released to the intestinal lumen. As a result, a decreased number of intestinal goblet cells, diminished tight junction protein expression, and imbalanced intestinal flora in mice were observed. These damages to the intestinal barrier ultimately led to the occurrence of colitis. Our study offers important insights into the cellular bioeffects and detrimental effects on intestinal health caused by RS particles and emphasizes the need to re-evaluate the safety of long-term RS consumption.

Short peptide-based supramolecular hydrogels appeared as highly interesting materials for applications in many fields. The optimization of their properties relies mainly on the design of a suitable hydrogelator through an empirical trial-and-error strategy based on the synthesis of various types of peptides. This approach is in part due to the lack of prior structural knowledge of the molecular architecture of the various families of nanofibers. The 3D structure of the nanofibers determines their ability to interact with entities present in their surrounding environment. Thus, it is important to resolve the internal structural organization of the material. Herein, using Fmoc-FFY tripeptide as a model amphiphilic hydrogelator and cryo-EM reconstruction approach, we succeeded to obtain a 3.8 Å resolution 3D structure of a self-assembled nanofiber with a diameter of approximately 4.1 nm and with apparently “infinite” length. The elucidation of the spatial organization of such nano-objects addresses fundamental questions about the way short amphiphilic N-Fmoc peptides lacking secondary structure can self-assemble and ensure the cohesion of such a lengthy nanostructure. This nanofiber is organized into a triple-stranded helix with an asymmetric unit composed of two Fmoc-FFY peptides per strand. The three identical amphiphilic strands are maintained together by strong lateral interactions coming from a 3-Fmoc zipper motif. This hydrophobic core of the nanofiber is surrounded by 12 phenyl groups from phenylalanine residues, nonplanar with the six Fmoc groups. Polar tyrosine residues at the C-term position constitute the hydrophilic shell and are exposed all around the external part of the assembly. This fiber has a highly hydrophobic central core with an internal diameter of only 2.4 Å. Molecular dynamics simulations highlight van der Waals and hydrogen bonds between peptides placed on top of each other. We demonstrate that the self-assembly of Fmoc-FFY, whether induced by annealing or by the action of a phosphatase on the phosphorylated precursor Fmoc-FFpY, results in two nanostructures with minor differences that we are unable to distinguish.