Science China Chemistry最新文献

The sensing and discrimination of different modified nucleosides are important in various key fields, including disease diagnosis and therapy, vaccine development, and so on. Due to the highly structural similarity and diversity of modified nucleosides, it is urgent but challenging to develop a simple and efficient method for accurate discrimination. Here, the discrimination and multiplex quantitation of modified RNA nucleoside are successfully achieved via a novel tetralactam macrocycle-based fluorescent sensor array for the first time. Based on the excellent ability of the endo-functionalized cavity of tetralactam macrocycle to distinguish structurally similar nucleobases in nucleosides, 16 nucleosides (including 4 unmodified, 6 methylated, and 6 other chemically modified nucleosides) with similar structures can be simultaneously discriminated with 100% accuracy. Furthermore, the concentrations of individual nucleosides in ternary mixtures are quantified simultaneously by support vector machine regression with high accuracy and immunity to interference, even in complicated human urine. In addition, the accurate discrimination of simulated cancer patient urine is realized by using the 3-element sensor array, validating its great potential in cancer precision medicine.

According to Le Chatelier’s principle, increasing the reaction pressure of O₂ is expected to significantly enhance H₂O₂ electrosynthesis performance, but this effect remains unexplored. By comparing various catalysts under different pressures, we uncover an intriguing phenomenon. Namely, in a pressurized electrolyzer (2.0 V, 30 bar O₂), a microporous metal-organic framework (MAF-2) with enzyme-mimicking dicopper(I) active sites on its pore surface achieved a current density of 90 mA cm⁻², Faradaic efficiency of ∼95%, a record yield rate of 4.2 mol g_cat⁻¹ h⁻¹, and record energy conversion efficiency of 27% for H₂O₂ production, generating pure and salt-free H₂O₂ at medical-grade concentration (3.3 wt%). Notably, this performance at 30 bar O₂ is seven times higher than at 1 bar O₂. The performance increase caused by this pressurization far exceeds those of other types of catalysts (e.g., carbon black and BBL-PcNi covalent framework), which rely solely on particle-surface active sites and exhibit <10% pressure response. Mechanism studies reveal that while O₂ struggles to enter MAF-2 pores at 1 bar (uptake < 2 cm³ g⁻¹), pressurization facilitates oxygen entering the pores (adsorption enthalpy = −45 kJ mol⁻¹, uptake = 40 cm³ g⁻¹ at 30 bar) and contact with abundant highly active dicopper(I) sites on the pore surface, thereby significantly enhancing its high-pressure performance. This study highlights the synergistic advantages of dual active sites and MOF porosities in electrocatalytic gas molecule conversion, providing critical insights for designing high performance catalysts under high pressure.

Natural lignin-derived room temperature phosphorescent materials have garnered significant interest due to their long-lived luminescence, large Stokes shifts, high quantum yields, and environmentally benign nature compared to petroleum-based counterparts. This review outlines principal preparation strategies, including confinement and spin-orbit coupling-enhancement approaches, along with highlighting their emerging applications in anti-counterfeiting, optoelectronics, and biomedical imaging. Furthermore, we analyze current technical challenges and conclude with forward-looking perspectives on sustainable processing, optical property regulation, and diverse applications. This review aims to provide comprehensive and insightful guidance for developing high-performance lignin-based photonic materials, potentially inspiring innovative approaches for sustainable optoelectronic technologies.

Development of novel photosensitizers (PSs) with high biocompatibility and biological uptake is of significance for efficient photodynamic anti-tumor or anti-bacterial. This study presents a smart self-assembly strategy of glyco-photosensitizers with near-infrared (NIR) emission and aggregation-induced generation reactive oxygen species (AIG-ROS) ability for cell imaging and photodynamic therapy (PDT) of both tumor cells and bacteria. Two photosensitizers, KL1 and KL2, are based on a “D-π-A” molecular architecture, featuring a tricyanofuran (TCF) acceptor and a tetraphenylethene (TPE) donor bridged by thiophene derivatives. After self-assembling with TPE-based glycoclusters (TPE-Glc₄), the resulting glyco-nanoparticles (KL1-G and KL2-G) exhibit improved water solubility and AIG-ROS capability, including singlet oxygen (¹O₂) and superoxide radicals (·O₂⁻) upon light irradiation. In cellular studies, TPE-glycoclusters facilitate the cellular uptake of PSs, thereby enhancing the NIR fluorescence signal and PDT efficiency for multiple kinds of cells. KL2-G shows superior phototoxicity, reducing cell viability to less than 5% at a low concentration of <5 μM under light irradiation. Additionally, KL2-G exhibits potential for photodynamic anti-bacterial applications against Escherichia coli. This work underscores the importance of glycoclustersmediated delivery in therapeutic efficacy enhancement of PSs and highlights the potential of glyco-nanoparticles in bioimaging and phototherapy applications.

Featuring excellent chemical stability and tunable pore aperture, zirconium-based metal-organic framework (Zr-MOF) represented by UiO-66 is promising for liquid molecular separation. Nevertheless, it is challenging to achieve high ion separation performance in UiO-66 membrane owing to the non-ideal pore environment. Here, we present a ligand engineering strategy to synergistically regulate pore size and functionality in Zr-MOF membrane for mono-/di-valent ions separation. This is achieved by positioning the amino group (-NH₂) in the ligand of the UiO-66 framework. The influences of amino groups on the lattice defects and pore functionality, as well as the ion separation performance of MOF membranes, were investigated systematically. Benefiting the properly narrowed pore size and enhanced repulsive force towards divalent ions, the optimized Zr-MOF membrane displayed excellent mono-/di-valent ions separation performance with monovalent ions permeation rate of 0.36–0.55 mol m⁻² h⁻¹ and mono-/di-valent ions selectivities of 64–98, far beyond the separation performance of state-of-the-arts membranes. This work provides a facile approach to precisely construct a nanosized space in crystalline membranes for molecular separation, energy conversion, and storage.

In the mid-1970s, surface-enhanced Raman spectroscopy (SERS) was discovered on an electrochemically roughened silver electrode surface, marking a milestone in the field of surface/interface analysis. Electrochemical SERS (EC-SERS), the initial application of SERS, has evolved into a powerful technique for acquiring fingerprint vibrational information from the interfaces and interphases in electrochemical systems, driven by advancements in nanoscience and nanotechnology, hence becoming one of the most significant spectroelectrochemical techniques for investigating electrochemical energy. However, achieving a groundbreaking discovery and subsequently establishing a new research field was a challenging and arduous endeavor. Therefore, it is essential to review the development of EC-SERS and its family members, including electrochemical tip-enhanced Raman spectroscopy (EC-TERS) and electrochemical shell-isolated nanoparticle-enhanced Raman spectroscopy (EC-SHINERS) over the past five decades. This review begins with the discovery of SERS in the mid-1970s, followed by the explosive growth driven by nanoscience and then the development of operando spectroelectrochemistry. Furthermore, the recent applications of in situ/operando studies in electrochemical energy storage and conversion, as well as investigations of corrosion inhibitors, electroplating, and electrodeposition, are discussed. Finally, a perspective on the new research paradigms, including emerging operando spectroelectrochemistry and artificial intelligence (AI)-nano-driven technologies for EC-SERS, is presented.

All-perovskite tandem solar cells (TSCs) have garnered significant attention due to their high efficiency potential. Among these, Sn-Pb perovskite solar cells (PSCs) play a crucial role in all-perovskite tandem configurations. However, the Sn²⁺ in Sn-Pb perovskites is prone to oxidation, leading to severe p-type self-doping and significant non-radiative recombination. Additionally, the uneven crystallization of Sn-Pb perovskites can result in non-uniform crystallization of the perovskite films, generating a substantial number of defects. In this study, we introduce sulfaguanidine (SG) into the perovskite precursor solution. The strong binding energy between SG and tin(II) iodide results in a delayed release of tin iodide during the crystallization process. Furthermore, the incorporation of SG significantly reduces the charge transfer between O₂ and Sn²⁺, thereby increasing the energy barrier for Sn²⁺ oxidation and effectively suppressing its oxidation. Consequently, the single-junction Sn-Pb PSCs exhibit a stable power conversion efficiency (PCE) of 22.70%. We further integrate the Sn-Pb perovskite into a two-terminal allperovskite TSC, achieving a PCE of 28.73%. Furthermore, the operational stability is further assessed by tracking the maximum power point (MPP) under AM 1.5G conditions. The encapsulated SG-modified tandem devices maintain 85.40% of their initial PCE after 250 h, demonstrating a significant improvement in stability.

Synthetic polypeptides are a class of important biomaterials due to their protein-like properties, unique secondary structures, capability to form a variety of complex self-assemblies, and excellent biocompatibility. These polypeptides are typically synthesized through the ring-opening polymerization (ROP) of amino acid N-carboxyanhydrides (NCAs), a widely used method that enables the production of polypeptides on a larger scale and with higher molecular weights (MWs) than other chemical and biological techniques. Conventional controlled NCA ROP methods often require expensive catalysts, rigorously anhydrous conditions, and complex apparatus, which restricts the broader application of polypeptides. In the past 20 years, our research group, along with many synthetic polypeptide chemists around the world, has made significant strides in simplifying controlled polypeptide synthesis. Our efforts began with the discovery of simplified NCA ROPs mediated by N-trimethylsilyl (N-TMS) amine initiator under anhydrous conditions, which minimizes the rate disparity between initiation and propagation and thus achieves excellent control. Building on this, we further uncovered the unprecedented α-helix-induced auto-acceleration in solvents with low dielectric constants and developed the cooperative covalent polymerization (CCP), which eventually brought the controlled synthesis to the open-air benchtop. This ultra-fast polymerization surpasses water-induced NCA hydrolysis, enabling the reaction to proceed in the presence of water. To further diminish the impurity-induced chain termination in CCP, we employed a bio-inspired water/oil emulsion system to achieve in situ segregation of impurities from NCA monomers. The new strategy, termed as Segregation-Induced Monomer-Purification and initiator-Localization promoted rate-Enhancement (SIMPLE) polymerization, facilitates the rapid, streamlined synthesis of well-defined polypeptides from amino acids. By eliminating the need for expensive catalysts, stringently anhydrous conditions, and tedious monomer purification, SIMPLE polymerization significantly simplifies the polymerization process and broadens the application of NCA ROP in developing high-performance polypeptides for advanced biomaterials.