Advanced Science最新文献

Linker-Based Structural Evolution

Phosphorus is a key element in the process of life origin. Polyphosphate is a phosphate “pool” in bacteria. In article number 2309602, Bing Tian, Ruhong Zhou, Shang Dai, and their co-workers demonstrate an interdomain linker-based exopolyphosphatase (PPX) structural evolution in bacteria. The length of α-linker in PPX, which involves phosphate cycling, is varied among bacteria and has impacts on protein's conformation and quaternary structure, thus poses an impact on enzyme activity and thermostability. The results suggest a potential relationship between PPX structural evolution and bacterial environmental adaptability, which shed light on enzymatic adaption for phosphorus cycling during natural evolution and rational design of the enzyme.

Wearable Ultra-broadband Photodetectors

In article number 2401631, Huanjun Chen and colleagues present a flexible and wearable graphene photodetector capable of ultra-broadband and rapid photoresponse at room temperature. Remarkably, the detectable wavelength range of this device spans from ultraviolet to millimeter wave spectrum, making it the broadest among all two-dimensional flexible detectors reported to date. Under simulated human body-wearing conditions, the device enables wide-spectrum imaging of shielded objects and material differentiation. The straightforward device architecture, coupled with its ultra-broadband operational wavelength range, is expected to have significant implications for applications in electronic skin, environmental sensing, and portable consumer electronics.

The clinical translation of tumor hypoxia intervention modalities still falls short of expectation, restricted by poor biocompatibility of oxygen-carrying materials, unsatisfactory oxygen loading performance, and abnormally high cellular oxygen consumption-caused insufficient hypoxia relief. Herein, a carrier-free oxygen nano-tank based on modular fluorination prodrug design and co-assembly nanotechnology is elaborately exploited, which is facilely fabricated through the molecular nanoassembly of a fluorinated prodrug (FSSP) of pyropheophorbide a (PPa) and an oxygen consumption inhibitor (atovaquone, ATO). The nano-tank adeptly achieves sufficient oxygen enrichment while simultaneously suppressing oxygen consumption within tumors for complete tumor hypoxia alleviation. Significant, the fluorination module in FSSP not only confers favorable co-assemblage of FSSP and ATO, but also empowers the nanoassembly to readily carry oxygen. As expected, it displays excellent oxygen carrying capacity, favorable pharmacokinetics, on-demand laser-triggerable ATO release, closed-loop tumor hypoxia relief, and significant enhancement to PPa-mediated PDT in vitro and in vivo. This study provides a novel nanotherapeutic paradigm for tumor hypoxia intervention-enhanced cancer therapy.

The dense mechanoreceptors in human fingertips enable texture discrimination. Recent advances in flexible electronics have created tactile sensors that effectively replicate slowly adapting (SA) and rapidly adapting (RA) mechanoreceptors. However, the influence of dermatoglyphic structures on tactile signal transmission, such as the effect of fingerprint ridge filtering on friction-induced vibration frequencies, remains unexplored. A novel multi-layer flexible sensor with an artificially synthesized skin surface capable of replicating arbitrary fingerprints is developed. This sensor simultaneously detects pressure (SA response) and vibration (RA response), enabling texture recognition. Fingerprint ridge patterns from notable historical figures - Rosa Parks, Richard Nixon, Martin Luther King Jr., and Ronald Reagan - are fabricated on the sensor surface. Vibration frequency responses to assorted fabric textures are measured and compared between fingerprint replicas. Results demonstrate that fingerprint topography substantially impacts skin-surface vibrational transmission. Specifically, Parks' fingerprint structure conveyed higher frequencies more clearly than those of Nixon, King, or Reagan. This work suggests individual fingerprint ridge morphological variation influences tactile perception and can confer adaptive advantages for fine texture discrimination. The flexible bioinspired sensor provides new insights into human vibrotactile processing by modeling fingerprint-filtered mechanical signals at the finger-object interface.

Materials exhibiting thermally activated delayed fluorescence (TADF) based on transition metal complexes are currently gathering significant attention due to their technological potential. Their application extends beyond optoelectronics, in particular organic light-emitting diodes (OLEDs) and light-emitting electrochemical cells (LECs), and include also photocatalysis, sensing, and X-ray scintillators. From the perspective of sustainability, earth-abundant metal centers are preferred to rarer second- and third-transition series elements, thus determining a reduction in costs and toxicity but without compromising the overall performances. This review offers an overview of earth-abundant transition metal complexes exhibiting TADF and their application as photoconversion materials. Particular attention is devoted to the types of ligands employed, helping in the design of novel systems with enhanced TADF properties.

The modulation of the chemical microenvironment surrounding metal nanoparticles (NPs) is an effective means to enhance the selectivity and activity of catalytic reactions. Herein, a post-synthetic modification strategy is developed to modulate the hydrophobic microenvironment of Ru nanoparticles encapsulated in a metal-organic framework (MOF), MIP-206, namely Ru@MIP-F_x (where x represents perfluoroalkyl chain lengths of 3, 5, 7, 11, and 15), in order to systematically explore the effect of the hydrophobic microenvironment on the electrocatalytic activity. The increase of perfluoroalkyl chain length can gradually enhance the hydrophobicity of the catalyst, which effectively suppresses the competitive hydrogen evolution reaction (HER). Moreover, the electrocatalytic production rate of ammonia and the corresponding Faraday efficiency display a volcano-like pattern with increasing hydrophobicity, with Ru@MIP-F₇ showing the highest activity. Theoretical calculations and experiments jointly show that modification of perfluoroalkyl chains of different lengths on MIP-206 modulates the electronic state of Ru nanoparticles and reduces the rate-determining step for the formation of the key intermediate of N₂H₂ ^*, leading to superior electrocatalytic performance.

Organic–Inorganic Metal Halide Materials

Temperature-dependent emission and time-resolved photodynamics of cis and trans water-coordinated isomers of methylammonium manganese bromide hybrids unravel different photobehaviors arising from free and self-trapped excitons. The materials are used for the fabrication of a color-tunable LED and detecting polar solvent vapors. More details can be found in article number 2400879 by Boiko Cohen, Abderrazzak Douhal, and co-workers.

Computational-Design

In 2400261 by Stephan W. Anderson, Xin Zhang, and co-workers, a computational method is reported to design wearable and tunable metamaterials via freeform auxetics for magnetic resonance imaging. The computational design tool offers an approach to solving complex circle packing problems in an interactive and efficient manner, thereby facilitating the design of deployable structures and the creation of mechanically tunable metamaterials configured in freeform shapes.

Given that tumor microenvironment (TME) exerts adverse impact on the therapeutic response and clinical outcome, robust TME modulators may significantly improve the curative effect and increase survival benefits of cancer patients. Here, Au nanodots-anchored CoFe₂O₄ nanoflowers with PEGylation (CFAP) are developed to respond to TME cues, aiming to exacerbate redox dyshomeostasis for efficacious antineoplastic therapy under ultrasound (US) irradiation. After uptake by tumor cells, CFAP with glucose oxidase (GOx)-like activity can facilitate glucose depletion and promote the production of H₂O₂. Multivalent elements of Co(II)/Co(III) and Fe(II)/Fe(III) in CFAP display strong Fenton-like activity for·OH production from H₂O₂. On the other hand, energy band structure CFAP is superior for US-actuated ¹O₂ generation, relying on the enhanced separation and retarded recombination of e^-/h⁺ pairs. In addition, catalase-mimic CFAP can react with cytosolic H₂O₂ to generate molecular oxygen, which may increase the product yields from O₂-consuming reactions, such as glucose oxidation and sonosensitization processes. Besides the massive production of reactive oxygen species, CFAP is also capable of exhausting glutathione to devastate intracellular redox balance. Severe immunogenic cell death and effective inhibition of solid tumor by CFAP demonstrates the clinical potency of such heterogeneous structure and may inspire more relevant designs for disease therapy.