ACS Central Science最新文献

Electron bifurcation reactions divide electrons from two-electron donors into high- and low-energy pools by transporting charge on spatially separated low- and high-potential electron hopping pathways. Bifurcation delivers electrons at potentials that drive downstream reactions in photosynthesis, respiration, and biocatalysis. Recent theoretical studies have described the requirements for effective ground-state electron bifurcation. The aim of this study is to design synthetic bifurcation constructs that can be driven by light. We describe a strategy to bifurcate holes (oxidizing equivalents) efficiently with light, and we present an illustrative energy landscape that could support this design. The design focuses on the electrochemical potentials and distances between cofactors. The analysis finds that hole bifurcation may be driven efficiently with light, guiding the further development of bioinspired networks that bifurcate charge and deliver the charges with prescribed electrochemical potentials.

Bioinspired light-driven hole bifurcating networks are designed based on de novo proteins, with the aim of separating holes into spatially separated pools at different electrochemical potentials.

The environmental scientist hitched a ride on a tourist cruise to measure pollutants in Antarctica.

Molecular interactions between receptors and ligands govern critical biological processes, from immune surveillance and T-cell activation to tissue development. However, current techniques for studying binding avidity often sacrifice throughput or precision. We introduce a high-throughput method for quantifying molecular and cellular binding kinetics using a centrifuge force microscope (CFM)─a compact imaging system integrated into a benchtop centrifuge. The CFM performs real-time force measurements on thousands of single cells in parallel, probing receptor–ligand interactions under controlled mechanical stress. To extend these capabilities, we developed a next-generation CFM with dual-channel fluorescence imaging that enables tracking of individual cell unbinding events. To demonstrate its utility, we profiled the binding mechanics of Bispecific T-cell Engager (BiTE) molecules, immunotherapeutic proteins that facilitate T-cell targeting of cancer cells. In cell–protein assays, we quantified the avidity of T and B cells interacting with BiTE-modified surfaces, revealing receptor-specific correlations between ligand concentration and bond strength. In cell–cell assays, we characterized BiTE-mediated adhesion between Jurkat and Nalm6 cells, demonstrating a time-dependent increase in avidity. By integrating force spectroscopy with fluorescence imaging, the CFM provides a high-throughput approach for investigating the mechanochemical principles underlying receptor-mediated interactions, with broad implications for biophysical chemistry, molecular recognition, and therapeutic development.

A high-throughput Centrifuge Force Microscope enables parallel, force-based unbinding studies of molecules or cells, using fluorescence to image single-cell immunological interactions.

Multivariate (MTV) porous materials exhibit unique structural complexities based on their diverse spatial arrangements of multiple building block combinations. These materials possess potential synergistic functionalities that exceed the sum of their individual components. However, the exponentially increasing design complexity of these materials poses significant challenges for accurate ground-state configuration prediction and design. To address this, we propose a Hamiltonian model for quantum computing that integrates compositional, structural, and balance constraints directly into the Hamiltonian, enabling efficient optimization of the MTV configurations. The model employs a graph-based representation to encode linker types as qubits. Our framework enables quantum encoding of a vast linker design space, allowing representation of exponentially many configurations with linearly scaling qubit resources, and facilitating efficient search for optimal structures based on predefined design variables. To validate our model, a variational quantum circuit was constructed and executed using the Sampling Variational Quantum Eigensolver (VQE) algorithm in the IBM Qiskit. Simulations on experimentally known MTV porous materials (e.g., Cu-THQ-HHTP, Py-MV-DBA-COF, MUF-7, and SIOC-COF2) successfully reproduced their ground-state configurations, demonstrating the validity of our model. Furthermore, VQE calculations were performed on a real IBM 127-qubit quantum hardware for validation purposes signaling a first step toward a practical quantum algorithm for the rational design of porous materials.

Quantum algorithms were developed to identify optimal multivariate porous material by exploring linker configurations encoded in qubits and were evaluated by the proposed Hamiltonian model.

Nanoconfinement provides a promising strategy to promote the electrochemical CO₂ reduction reaction (CO₂RR) owing to enhanced reactant enrichment and collision. However, the nanoconfinement influence on the CH₄ selectivity from the CO₂RR with related regulation mechanism is unclear. Herein, a series of mesoporous CeO₂ loaded Cu catalysts with controllable pore size (1.3–5.5 nm) are designed to modulate the CO₂RR selectivity to CH₄. It is found that decreasing the pore size can apparently enhance the CO₂RR performance while inhibiting the HER activity. Moreover, a volcano-type relationship between the CH₄ selectivity and the pore diameter is observed among these catalysts, while Cu-mCeO₂-3.0 (pore diameter of 3.0 nm) shows the highest CH₄ Faradaic efficiency (66.1 ± 2.9%). The in situ experiments and DFT calculations illustrate that a smaller pore size with stronger confinement over Cu-mCeO₂-x can promote the adsorption and transformation of reactants (*CO, *CHO, etc.) for CH₄ production, but too narrow confined space (1.3 nm) will contribute to much higher intermediate coverage and promote their collision for C–C coupling to C₂₊ products instead, thus reducing the CH₄ selectivity. This work provides designing insights into metal/oxide catalysts with controllable pore size to study the nanoconfinement effect on the CO₂RR-to-CH₄ activity, which can be extended to other oxide-based catalytic reactions.

This study establishes a correlation between the CO₂RR-to-CH₄ activity and the pore size of mesoporous Cu-CeO₂ catalysts, elucidating the underlying regulation mechanisms.

Sodium-ion batteries (SIBs) are considered potential alternatives to lithium-ion batteries (LIBs) due to the abundant resources and low sodium cost. The rational nanostructural design for anode materials plays a crucial role in SIBs. TiO₂, as a common electrode material, suffers from the drawbacks of low specific surface area and poor conductivity. To overcome these limitations, we propose a strategy combining solvent evaporation-induced self-assembly and chemical oxidative polymerization to construct an ultrathin polypyrrole (PPy)-coated mesoporous TiO₂ microsphere (meso-TiO₂@PPy) core–shell structure. The combination of the mesoporous structure and the conductive coating endows the micrometer-sized TiO₂ spheres with high specific surface area, excellent conductivity, and abundant sodium-ion diffusion pathways, leading to a dominant pseudocapacitance (94%) of total charge storage. Remarkably, such integration allows for a high reversible capacity of 160.6 mAh g^–1 at 1 A g^–1, good rate performance, and stable cycling performance (capacity retention of 80.8% after 2000 cycles). Our research provides a pathway for the design of compositive anode materials for high-performance SIBs.

A type of integrated mesoporous TiO₂−PPy composite is designed as an anode to guarantee high surface area, tap density, and conductivity for overall enhancement of pseudocapacitive Na⁺ storage.

The climate-resistant bean boasts a chemical profile similar to Arabica’s.

The stretchability (ability to be elongated) and toughness (capacity to absorb energy before breaking) of polymer network materials, such as elastomers and hydrogels, often determine their utility and lifetime. Direct correlations between the molecular behavior of polymer network components and the physical properties of the network inform the design of materials with enhanced performance, extended lifetime, and minimized waste stream. Here, we report the impact of the fused ring size in bicyclic cyclobutane mechanophores within the strands of polymer network gels. The mechanophores and their polymer strands share the same initial covalent contour length, whereas the capacity for reactive strand extension (RSE) is varied by changing the size of the ring fused to the cyclobutane from 5 to 12 carbon atoms. We observe the first evidence of covalent RSE effects in a single-network gel, and strands with greater RSE lead to gels with greater stretchability and toughness. The same qualitative correlation between molecular and macroscopic extension is also observed in DN hydrogels with mechanophores in the prestretched first network.

The strain at break of polymer network materials can be tuned by varying the molecular length hidden behind embedded cyclobutane mechanophores.

The lipid composition of cellular membranes is highly dynamic and undergoes continuous remodeling, affecting the biophysical properties critical to biological function. Here, we introduce an optical approach to manipulate membrane viscosity based on an exogenous synthetic fatty acid with an azobenzene photoswitch, termed FAAzo4. Cells rapidly incorporate FAAzo4 into phosphatidylcholine and phosphatidylethanolamine in a concentration- and cell type-dependent manner. This generates photoswitchable PC and PE analogs, which are predominantly located in the endoplasmic reticulum. Irradiation causes a rapid photoisomerization that decreases membrane viscosity with high spatiotemporal precision. We use the resulting “PhotoCells” to study the impact of membrane viscosity on ER-to-Golgi transport and demonstrate that this two-step process has distinct membrane viscosity requirements. Our approach provides an unprecedented way of manipulating membrane biophysical properties directly in living cells and opens novel avenues to probe the effects of viscosity in a wide variety of biological processes.

PhotoCells enable the dynamic control of protein viscosity in living cells. A decrease of membrane viscosity increases the amount of protein recruited at ERES but slows down the transport to Golgi.

The development of artificial catalysts with efficiency that can rival those of Nature’s enzymes represents one of the foremost yet challenging goals in homogeneous metal catalysis. Inspired by the exceptional performance of metalloenzymes, the design and development of highly efficient bi/multinuclear catalysts via judicious ligand design, by taking advantage of the cooperative action of the proximal catalytic sites, has attracted great attention. Herein, we report the self-assembly of a chiral hexadentate BINOL-dipyox ligand with zinc acetate into a well-defined trinuclear zinc complex, which demonstrated ultrahigh catalytic productivity in the enantioselective hydroboration of ketones with an unprecedented turnover number (TON) of 19,400 at an extremely low catalyst loading (0.005 mol %). Mechanistic investigations reveal that a cooperative Lewis acid activation mode is operating in the catalytic process, hence, underscoring the unique advantages of the trinuclear architecture.

This work reports the rational design and self-assembly of an artificial chiral trinuclear zinc catalyst, which exhibits exceptional efficiency in enantioselective ketone hydroboration.