ACS Central Science最新文献

Solution-state photocatalysis is fundamentally reliant on the use of organic solvents, which are associated with significant safety, sustainability, and implementation challenges for conducting light-driven reactions. Mechanophotocatalysis tantalizingly addresses these issues by significantly reducing the use of reaction solvents, using mechanical mixing to mediate light-driven transformations. In this Outlook, we examine the motivations for combining photocatalysis with mechanochemistry, assess how this nascent methodology has evolved, and speculate on future research directions that should be explored in order for mechanophotocatalysis to emerge as a useful and complementary methodology for conducting photochemical reactions under solvent-minimized conditions.

Light-driven reactions, facilitated by mechanical mixing, have the potential to revolutionize photochemistry. This Outlook explores the development and potential applications of mechanophotocatalysis.

Developing high-energy-density lithium metal batteries (LMBs) is challenging due to critical safety concerns and cycling instability. A highly fluorinated diluent offers improved safety features but fails to form miscible electrolytes. Herein, we address these key issues through the design of miscible fluorous electrolytes enabled by molecular engineering of anions with fluoro-alkyl moieties, creating an effective molecular bridge between solvents and fluorous diluents. Detailed spectroscopy and molecular dynamics simulations reveal the critical amphiphilic anion chemistry inward and outward of the Li⁺ solvation sheath: fluorophilic interactions (F···F) with the diluent and atypical hydrogen-bonding (F···H) with the solvent. The designed miscible fluorous electrolyte, featuring diluents with ultrahigh F/H atomic ratios of 4.33 or higher, exhibits not only remarkable nonflammability safety properties, but also dendrite-free Li plating/stripping with a high Coulombic efficiency (CE) of 99.53% and long-term cycling stability in Li||NCM811 batteries. LiF-rich interphases formed at the electrode–electrolyte interface and the unique electrolyte formulation greatly enhance the battery performance and safety profile, as characterized by delayed onset and peak temperatures of thermal runaway reactions. This study demonstrates a general approach for engineering high-safety electrolytes, advancing next-generation LMBs that overcome the traditional trade-off between performance and safety.

Amphiphilic anions bridge solvents and fluorous diluents, creating nonflammable electrolytes that resolve the safety-performance trade-off in lithium metal batteries.

Spin correlations between radicals underpin key biological processes, and spin relaxation describes their decay due to environmental interactions. Radical pairs involving lipid peroxide radicals in bilayers have been proposed as a source of magnetic field effects (MFEs) in lipid autoxidation, but their viability has been questioned due to rapid relaxation in dynamic membranes. This study investigates whether MFEs can persist in lipid bilayers despite spin relaxation. Using an integrative approach combining all-atom molecular dynamics simulations, density functional theory (DFT) calculations, and spin dynamics modeling using Bloch–Redfield–Wangsness relaxation theory, we investigate a palmitoyl-linoleoyl-phosphatidylcholine (PLPC) model membrane containing 13ze-lipid peroxide radicals. We identify the peroxide group rotation and the lipid backbone dynamics as key drivers of spin relaxation. By computing g-tensors and hyperfine coupling constants via DFT and incorporating their molecular-dynamics-derived fluctuations into spin-dynamics simulations, we assess relaxation from hyperfine interactions, g-tensor fluctuations, and spin-rotational coupling. Our results demonstrate that MFEs persist in lipid bilayers despite thermal motion. Relaxation is dominated by g-fluctuations, which enhance MFEs at high magnetic fields. Surprisingly, our calculations also suggest possible MFEs in weak magnetic fields. These findings broaden the understanding of biological MFEs and highlight potential biomedical implications for ferroptosis, cancer, and oxidative stress-related diseases.

Spin relaxation is not precluding radical-pair-induced magnetic field effects in lipid peroxidation, thereby supporting magnetosensitivity of various biological processes in health and disease.

The azobenzene-containing agonist of the vitamin D receptor, PhotoVDRM, enables spatiotemporal psoriasis treatment in mice; its cisoid form induces potent anti-inflammation without hypercalcemia.

As people with α-gal syndrome seek to boost awareness, researchers are looking to harness the molecule for new therapies.

As US teachers discover more and more legacy chemicals in schools, funding for cleanup is hard to find. Educators, nonprofits, and local governments are stepping in to help.

Potassium ions (K⁺) are vital for biological systems and essential cellular functions, making their homeostasis monitoring crucial for investigating electrolyte imbalance symptoms. Antibody-based high-throughput single-cell sequencing enables simultaneous phenotype and genotype profiling in individual cells; however, its application to ion monitoring encounters inherent limitations. The subnanometer scale of K⁺ ions precludes antibody-based detection, creating a significant technical barrier for correlating ionic activity with cellular phenotypes at single-cell resolution. In this study, we report a cell surface biosensor for single-cell ion sequencing (Ion-seq) to monitor K⁺ homeostasis in clinical samples. The design utilizes split G-quadruplex (G4), where two guanine-rich DNA oligonucleotides cofold into four-stranded noncanonical secondary structures upon K⁺ binding. Specifically, a lipid-labeled capture probe anchors to the cell membrane. Upon drug-stimulated release of K⁺ from cells, the free sensing probe is captured, forming a complete G-quadruplex with the capture probe. Sequencing the sensing probe then enables monitoring of potassium homeostasis at single-cell resolution, allowing ionic phenotyping within the context of cellular heterogeneity and function. Moreover, this biosensor holds potential for broader bioapplications in analyzing other ions at the single-cell resolution, advancing disease diagnosis and personalized medicine.

Based on split G-quadruplex probe, a technology for single-cell ion sequencing was developed. And we obtained single-cell resolution potassium ion profiling in the colorectal cancer microenvironment.

This Outlook aims to update the longstanding treatment of airborne disease transmission through an interdisciplinary lens combining biology, surface chemistry, and aerosol physics, drawing parallels between environmental and human-generated infectious aerosols and examining their effects on human and ecosystem health. By recasting the lung surface as a dynamic interface akin to the ocean surface, this Outlook illustrates the importance of a multidisciplinary approach to elucidate the mechanisms of disease transmission at a depth that enables practical mitigation strategies. The urgency of this analysis is motivated by the evolving nature of airborne pathogens of concern, such as SARS-CoV-2 and influenza, and the global impact of dynamic environments on the poorly understood airborne microbiome.

We describe how present knowledge of microbial transfer across the air-sea interface can inspire new approaches to understanding respiratory pathogen transfer from the lungs.

The human gut microbiome consists of diverse microbes that communicate through small molecules. Numerous recent studies have demonstrated links between gut microbiota and host physiological processes; however, the underlying metabolites remain elusive in part because laboratory conditions do not replicate the native environment of these bacteria. Herein, we focused on Bacteroides dorei, a predominant and representative member of human gut microbiota, to interrogate the chemical composition and possible biological functions of its secondary metabolome. Using UPLC-MS-guided high-throughput elicitor screening (HiTES), we examined how the metabolome of this commensal bacterium responds to hundreds of FDA-approved drug molecules that the host may intake. We identified low-dose tetracyclines as pleiotropic inducers of the B. dorei secondary metabolome, leading to the identification and structural elucidation of six serine-glycine dipeptide lipids, named doreamides A–F, and two 6-N-acyladenosines. The induced doreamides and N-acyladenosines exhibited pro-inflammatory activities, upregulating tumor necrosis factor α (TNFα), interleukin (IL)-1β, IL-6, and IL-10 in macrophages. Doreamides also triggered production of cathelicidin, which inhibits the growth of multiple bacteria tested but not B. dorei. Our results show that low-dose antibiotics can perturb the secondary metabolome of gut bacteria, and that these induced metabolites can exert immunomodulatory effects and restructure the microbiome.

Low-dose tetracyclines elicit production of dipeptide lipids and 6-N-acyladenosines in the important gut commensal Bacteroides dorei, which in turn induce inflammation and restructure the microbiome.