Near Infrared Light-Triggered Photocatalytic Decaging for Remote-Controlled Spatiotemporal Activation in Living Mice**

Spatiotemporal manipulation of biological processes in living animals using noninvasive, remote-controlled stimuli is a captivating but challenging endeavor. Herein, we present the development of a biocompatible photocatalytic technology termed CAT-NIR, which uses external near infrared light (NIR, 740 nm) to trigger decaging reactions in living mice. The Os(II) terpyridine complex was identified as an efficient NIR photocatalyst for promoting deboronative hydroxylation reactions via superoxide generation in the presence of NIR light, resulting in the deprotection of phenol groups and the release of bioactive molecules under living conditions. The validation of the CAT-NIR system was demonstrated through the NIR-triggered rescue of fluorophores, prodrugs as well as biomolecules ranging from amino acids, peptides to proteins. Furthermore, by combining genetic code expansion and computer-aided screening, CAT-NIR could regulate affibody binding to the cell surface receptor HER2, providing a selective cell tagging technology through external NIR light. In particular, the tissue-penetrating ability of NIR light allowed for facile prodrug activation in living mice, enabling noninvasive, remote-controlled rescue of drug molecules. Given its broad adaptability, this CAT-NIR system may open new opportunities for manipulating the functions of bioactive molecules in living animals using external NIR light with spatiotemporal resolution.     

Dispersive liquid-liquid microextraction based on a supramolecular solvent followed by high-performance liquid chromatographic analysis of lignans in Forsythiae Fructus

A supramolecular solvent-based dispersive liquid-liquid microextraction was proposed for the extraction and determination of lignans in Forsythiae Fructus combined with high-performance liquid chromatography. The supramolecular solvent, consisting of tetrabutylammonium bromide and n-hexanol, was mixed with the sample solution to extract the analytes by a vortex. After accomplishing the extraction, the extraction phase was separated by centrifugation and collected for high-performance liquid chromatography analysis. In this work, the important extraction variables such as the type and amount of extraction solvent, pH and salt amount in the sample phase, and extraction time were optimized. The synthesis of supramolecular solvent was studied and its microstructure was characterized by transmission electron microscopy. Under the optimal conditions, the analytes’ enrichment factors were between 6 and 170 for the proposed procedure. Satisfactory linear ranges (r ≥ 0.99), detection limits (0.025–0.4 ng/ml), precisions (< 9.2%), and accuracies (recoveries: 96.5%–104.8%) were obtained. The method has been successfully applied to the preconcentration of lignans in Forsythiae Fructus with simple and rapid operation, low cost, and environmental friendliness.     

计算化学在紫外可见吸收光谱教学中的应用

以L-酪氨酸为案例,结合计算化学手段,设计了采集紫外可见吸收光谱的教学方案,并探讨了计算化学在紫外可见吸收光谱教学中的具体应用。通过对该分子紫外可见光谱的模拟与指认,以及利用多种方法对其不同电子激发过程开展分析,不仅可以有效解释实验光谱吸收峰的来源,还能获取一系列具有教学意义的等值面图形与数据,来帮助学生加强对轨道跃迁类型、电子转移与空穴-电子分布等电子激发特性方面的感性认识,从而使得教学内容既有趣生动,又富有理论深度。     

Boosting Electroreduction Kinetics of Nitrogen to Ammonia via Atomically Dispersed Sn Protuberance

Atomically dispersed metal catalysts show potential advantages in N₂ reduction reaction (NRR) due to their excellent activity and efficient metal utilization. Unfortunately, the reported catalysts usually exhibit unsatisfactory NRR activity due to their poor N₂ adsorption and activation. Herein, we report a novel Sn atomically dispersed protuberance (ADP) by coordination with substrate C and O to induce positive charge accumulation on Sn site for improving its N₂ adsorption, activation and NRR performance. The extended X-ray absorption fine structure (EXAFS) spectra confirmed the local coordination structure of the Sn ADPs. NRR activity was significantly promoted via Sn ADPs, exhibiting a remarkable NH₃ yield (R_NH3) of 28.3 μg h⁻¹ mg_cat⁻¹ (7447 μg h⁻¹ mg_Sn⁻¹) at −0.3 V. Furthermore, the enhanced N₂H_x intermediates was verified by in situ experiments, yielding consistent results with DFT calculation. This work opens a new avenue to regulate the activity and selectivity of N₂ fixation.     

Unlocking the Transition of Electrochemical Water Oxidation Mechanism Induced by Heteroatom Doping

Heteroatom doping has emerged as a highly effective strategy to enhance the activity of metal-based electrocatalysts toward the oxygen evolution reaction (OER). It is widely accepted that the doping does not switch the OER mechanism from the adsorbate evolution mechanism (AEM) to the lattice-oxygen-mediated mechanism (LOM), and the enhanced activity is attributed to the optimized binding energies toward oxygen intermediates. However, this seems inconsistent with the fact that the overpotential of doped OER electrocatalysts (<300 mV) is considerably smaller than the limit of AEM (>370 mV). To determine the origin of this inconsistency, we select phosphorus (P)-doped nickel-iron mixed oxides as the model electrocatalysts and observe that the doping enhances the covalency of the metal-oxygen bonds to drive the OER pathway transition from the AEM to the LOM, thereby breaking the adsorption linear relation between *OH and *OOH in the AEM. Consequently, the obtained P-doped oxides display a small overpotential of 237 mV at 10 mA cm⁻². Beyond P, the similar pathway transition is also observed on the sulfur doping. These findings offer new insights into the substantially enhanced OER activity originating from heteroatom doping.     

Bio-Inspired Polyanionic Electrolytes for Highly Stable Zinc-Ion Batteries

For zinc-ion batteries (ZIBs), the non-uniform Zn plating/stripping results in a high polarization and low Coulombic efficiency (CE), hindering the large-scale application of ZIBs. Here, inspired by biomass seaweed plants, an anionic polyelectrolyte alginate acid (SA) was used to initiate the in situ formation of the high-performance solid electrolyte interphase (SEI) layer on the Zn anode. Attribute to the anionic groups of −COO⁻, the affinity of Zn²⁺ ions to alginate acid induces a well-aligned accelerating channel for uniform plating. This SEI regulates the desolvation structure of Zn²⁺ and facilitates the formation of compact Zn (002) crystal planes. Even under high depth of discharge conditions (DOD), the SA-coated Zn anode still maintains a stable Zn stripping/plating behavior with a low potential difference (0.114 V). According to the classical nucleation theory, the nucleation energy for SA-coated Zn is 97 % less than that of bare Zn, resulting in a faster nucleation rate. The Zn||Cu cell assembled with the SA-coated electrode exhibits an outstanding average CE of 99.8 % over 1,400 cycles. The design is successfully demonstrated in pouch cells, where the SA-coated Zn exhibits capacity retention of 96.9 % compared to 59.1 % for bare Zn anode, even under the high cathode mass loading (>10 mg/cm²).     

Inside Cover: Mechanistic Understanding of Efficient Polyethylene Hydrocracking over Two-Dimensional Platinum-Anchored Tungsten Trioxide (Angew. Chem. Int. Ed. 40/2023)

Chemical upcycling of polyethylene (PE) can convert plastic waste into valuable resources. However, engineering a catalyst that allows PE decomposition at low temperatures with high activity remains a significant challenge. Herein, we anchored 0.2 wt.% platinum (Pt) on defective two-dimensional tungsten trioxide (2D WO₃) nanosheets and achieved hydrocracking of high-density polyethylene (HDPE) waste at 200–250 °C with a liquid fuel (C_5–18) formation rate up to 1456 g_products ⋅ g_{metal species}⁻¹ ⋅ h⁻¹. The reaction pathway over the bifunctional 2D Pt/WO₃ is elucidated by quasi-operando transmission infrared spectroscopy, where (I) well-dispersed Pt immobilized on 2D WO₃ nanosheets trigger the dissociation of hydrogen; (II) adsorption of PE and activation of C−C cleavage on WO₃ are through the formation of C=O/C=C intermediates; (III) intermediates are converted to alkane products by the dissociated H. Our study directly illustrates the synergistic role of bifunctional Pt/WO₃ catalyst in the hydrocracking of HDPE, paving the way for the development of high-performance catalysts with optimized chemical and morphological properties.     

Simultaneous Determination of Ramipril and Its Active Metabolite Ramiprilat in Human Plasma by LC–MS–MS

A selective, rapid and sensitive liquid chromatography tandem mass spectrometry method has been developed for the simultaneous determination of ramipril and ramiprilat in human plasma using enalapril as the internal standard via one-step extraction with ethyl acetate under acidic condition. The analysis was carried out on a Diamonsil C₁₈ column (150 mm × 4.6 mm i.d., 5 μm) with a mobile phase consisting of 1% formic acid-acetonitrile (25:75, v/v) at a constant flow rate of 0.5 mL min^?1. The detection was performed on a triple-quadruple tandem mass spectrometer by selective reaction monitoring mode via electrospray ionization. Linear calibration curves of ramipril and ramiprilat were obtained in the concentration range of 0.107–107.0 and 0.262–105.0 ng mL^?1, respectively. The intra- and inter-day precision (RSD) values were below 8.2 and 4.8% for ramipril, 10.4 and 12.3% for ramiprilat, and accuracy (RE) were within ±5.5 and ±3.2%, respectively at all QC levels. The method was utilized to support clinical pharmacokinetic studies in healthy volunteers following oral administration of ramipril tablets.     

Mesoscopic dynamics of inhomogeneous polymers based on variable cell shape dynamic self-consistent field theory

In this paper, we combine variable cell shape method with dynamic self-consistent field theory and extend to study structure and dynamics under shear for triblock copolymer melts. Due to shear, the calculation cell shape is variable and no longer orthogonal. Pseudospectral method is employed to solve the diffusion equation for chain propagator on the nonorthogonal coordinate and the shear periodical condition can be easily designed in terms of the variable cell shape method. By using this strategy, the shear induced morphology evolution is investigated for topologically complex polymeric systems such as linear and star triblock copolymers; the morphology of linear ABC triblock copolymers is more shear sensitive than that of star triblocks. In particular, once the chain propagator is obtained, the microscopic elastic stress and spatial stress distribution can be derived and thus the dynamic mechanical property can be calculated under shear. By imitating the dynamic storage modulus G' corresponding to any given morphology in the oscillatory shear measurements, we explore the relationship between the morphology and the storage modulus G' and extend to study the mechanism of phase separation dynamics as well as order-disorder transition (ODT) for linear and star triblock copolymers. The results show that the chain architecture can be easily distinguished by investigating the ODT, though the systems such as AB symmetric diblock and ABA triblock copolymers by coupling AB precursors almost exhibit similar microstructures. In addition, the storage modulus G' and loss modulus G" can be simultaneously determined in frequency sweeps of oscillatory shear measurements and the dependence of the moduli on phase separated patterns and the chain topology is investigated. The simulation findings are in qualitatively agreement with the experimental results.     

Influence of magnesia modification on the properties of copper oxide supported on gamma-alumina

XRD, BET, TPR, UV-vis DRS and in situ FT-IR were employed to investigate the dispersion, reduction and CO(2)-adsorption behaviors of copper oxide supported on magnesia modified gamma-Al(2)O(3) (Mg-Al) samples. The results indicate that magnesia could be highly dispersed on the surface of gamma-Al(2)O(3) to form a monolayer and the dispersion capacity is about 1.55 mmol/(100 m(2)gamma-Al(2)O(3)). For copper oxide supported on Mg-Al samples, both the dispersion capacity and the reduction temperature of surface CuO decrease with the MgO loading. CO(2)-adsorption IR results show that the surface strong basic amount for the catalysts increases with the dispersed MgO loading. In addition, the activity of CO oxidation suggests that the main active species in this system should be small CuO cluster and the existence of dispersed MgO enhances the activity of CO oxidation. The catalysts might be applied in pollution control devices for vehicle exhaust, CO gas sensors, catalytic combustion and gas purification of CO(2) lasers. All the results have been discussed by the consideration of the variation of gamma-Al(2)O(3) surface structure before and after magnesia modification.