Small Methods最新文献

Peroxynitrite (ONOO^-) is a key mediator of redox imbalance in inflammation and cancer, with in vivo monitoring of its dynamic behavior still posing a major challenge. Here, we developed a BD@PEG nanoprobe that enabled dual-excitation NIR-II ratiometric imaging with superior biocompatibility, quantitative fidelity, and ONOO^- selectivity. When applied to a drug-induced liver injury model, BD@PEG-based NIR-II ratiometric imaging allowed real-time monitoring of hepatic ONOO^- dynamics, directly correlating oxidative/nitrosative stress to histopathological alterations, and demonstrating significant attenuation under glutathione treatment. In a CT26 tumor model, the NIR-II ratiometric imaging strategy revealed distinct ONOO^- modulation in response to different therapeutic interventions. Furthermore, two-plex imaging by integrating NIR-IIb oxyhemoglobin saturation analysis afforded concurrent assessment of nitrosative stress and vascular oxygenation. We found that the combination of chemotherapy and immunotherapy induced synergistic ONOO^- production, enhanced immune cell infiltration, and achieved superior antitumor efficacy. Overall, this study established a versatile imaging platform for dynamic redox monitoring and oxygenation assessment in vivo, providing mechanistic insight into ONOO^--mediated pathology and a translational tool for optimizing therapeutic interventions in cancer and inflammation.

We demonstrate a "dry additive" strategy to enhance fully vacuum-deposited perovskite solar cells (PSCs) by co-evaporating diphenyl sulfoxide (DPSO) as a volatile solid additive during film formation. Vacuum-processed perovskite films often exhibit high nucleation densities and small grain sizes, which limit crystallinity and increase defects. Introducing DPSO-a Lewis base that temporarily binds perovskite precursors and slows their reaction, modulates nucleation, and enables the growth of much larger perovskite domains. DPSO-treated films show improved crystallinity, lower defect density, and enhanced charge-transport pathways due to reduced grain-boundary density. Power conversion efficiency (PCE) gains are modest for thicker films (peak ∼18.0% vs. ∼17.3% for control at 350 nm), but substantial in ultrathin devices, particularly at 200 nm, where high efficiency is maintained despite significant thickness reduction. PSCs with ∼200 nm active layers achieve PCEs around 17% with DPSO, compared to ∼3% without, and even a 150 nm DPSO-assisted film reaches over 11% efficiency. This capability to fabricate ultrathin (∼150-200 nm) layers with competitive efficiencies is important for developing lightweight and semitransparent solar cells. Notably, the DPSO-based approach also yields enhanced device stability-PSCs retain ∼94% of their initial efficiency after 720 h of ambient storage, far outperforming control devices.

Recent advances in nanotechnology have created the need to manufacture 3D nanostructures with controlled material composition. Focused Electron Beam Induced Deposition (FEBID) is a nanoprinting technique offering highest spatial resolution combined with the ability to directly 3D-print almost any shape. It relies on local electron-induced dissociation of metal-ligand organometallic molecules adsorbed onto a substrate. So far FEBID continuum modeling involves the surface kinetics of precursor molecules during electron irradiation and succeeds in the prediction of nanoprint shape and growth rate and forms nowadays the basis of software for 3D nano-printing of nanostructures. Here, the model is expanded to the surface kinetics of detached ligands. Involving their dissociation and desorption behavior allows to predict trends in the metallic composition of the nanoprinted material and to define desirable nanoprint process windows as function of electron exposure time and flux. The theoretical foundations of the model is presented, validate it experimentally for chromium and silver precursors, compare calculated values with literature data for various precursors, and discuss its potential to design new experiments. This contribution enhances the understanding of FEBID dynamics and provides a versatile framework for predictive FEBID material nano-printing.

Understanding the dynamics of complex heterogeneous battery materials under realistic operation conditions with micrometer spatial and relevant temporal resolutions remains challenging. This work presents a synchrotron-based operando chemical imaging methodology using microfocus X-ray diffraction (µ-XRD) scanning imaging. The approach is applied to an all-solid-state battery (ASSB) with high-energy lithium-rich nickel manganese cobalt layered oxide (Li-rich NCM) as active cathode material, Li₃YCl₆ as catholyte, amorphous Li₃PS₄ separator layer, and metallic lithium as anode. Operando XRD mapping unveils the nature and location of phase transformations along one complete cycle. The ASSB is integrated in the multipurpose custom-designed electrochemical cell, which allows optimal exit solid angle for XRD analysis, permitting the resolution of the local chemistry in time and space across a relatively large field of view. We observed the following phenomena: (i) heterogeneous lithiation and delithiation processes within tens of individual Li-rich NCM particles, indicating intraparticle differential lithium diffusion, (ii) the reversible formation of YCl₂(H₂O)₆Cl, attributed to water residues, and (iii) the irreversible dissolution of Li₂S and formation of LiOH parasitic phases. (iii) This study opens new perspectives for broader applications in energy technologies, such as Na-ion, Zinc-Air, Li-air, Li-ion, and Li-S.

Heterogeneous Catalysis

The immobilization of fullerene C₆₀ on cellulose thread allows heterogeneous photoreaction screening to be achieved through a thread spray mass spectrometry platform. Fullerene C₆₀ is identified to facilitate dehydro-dimerization reactions from amines, including the discovery that norharmane can serve as an efficient precursor of antioxidants to quench singlet oxygen. More in article number 2500911, Badu-Tawiah and co-workers.

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In article number 2500715, Pal, Saikia, and co-workers synthesized a series of Ti₃C₂/CdIn₂S₄ heterojunction photocatalysts through the in-situ growth of CdIn₂S₄ microflowers on Ti₃C₂ MXene nanosheets to enhance the process of photocatalytic hydrogen evolution. The growth of CdIn₂S₄ microflowers on the MXene nanosheets does not change the overall sheet structure of Ti₃C₂ MXene. The optimized photocatalyst achieved an impressive hydrogen evolution rate of 9.799 mmol g⁻¹ h⁻¹.

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In article number 2402238, Tan, Yang, and co-workers introduce an on-chip microlens array that enhances light scattering for single-particle tracking. Leveraging long-range optical fields, the chip achieves 76-fold signal amplification. This enables 2.9 nm localization precision for 60 nm gold nanoparticles at 200 μs resolution under low-power bright-field microscopy, empowering researchers to perform high-sensitivity biosensing without specialized equipment, making nanoparticle analysis widely accessible.

Inside Front Cover

In article number 2500518, Yang, Zou, Chen, Sun, and co-workers summarize the types of self-assembled fluorescent peptide nanoprobes and the progress of their applications in disease diagnosis. In addition, this review further discusses the current limitations of their development and new strategies for developing advanced peptide-based fluorescent self-assembling nanoprobes to enhance their potential for clinical translation.

Inside Back Cover

In article number 2500667, Park and co-workers develop a novel RHEA-Cu composite using a liquid metal dealloying process. The resulting bi-continuous structure synergistically combines the high thermal conductivity of Cu channels for efficient heat dissipation with the superior mechanical strength and irradiation resistance of the RHEA matrix to withstand damage. This work offers a new strategy for creating high-performance materials for extreme environments, such as next-generation nuclear reactors.

Photonic Sensors

In article number 2500727, Zhang, Li, and co-workers propose a fully packaged wearable integrated photonics sensing solution featuring a high-Q necklace-shaped microring resonator and a fiber array with a grating coupler for plug-and-play functionality. This system, enhanced with artificial neural networks, achieves 97% accuracy in real-time monitoring and classification of 15 human motions and specific physiological signals.