Widely Adaptable Oil-in-Water Gel Emulsions Stabilized by an Amphiphilic Hydrogelator Derived from Dehydroabietic Acid

A surfactant, R-6-AO, derived from dehydroabietic acid has been synthesized. It behaves as a highly efficient low-molecular-weight hydrogelator with an extremely low critical gelation concentration (CGC) of 0.18 wt % (4 mm ). R-6-AO not only stabilizes oil-in-water (O/W) emulsions at concentrations above its critical micelle concentration (cmc) of 0.6 mm , but also forms gel emulsions at concentrations beyond the CGC with the oil volume fraction freely adjustable between 2 % and 95 %. Cryo-TEM images reveal that R-6-AO molecules self-assemble into left-handed helical fibers with cross-sectional diameters of about 10 nm in pure water, which can be turned to very stable hydrogels at concentrations above the CGC. The gel emulsions stabilized by R-6-AO can be prepared with different oils (n-dodecane, n-decane, n-octane, soybean oil, olive oil, tricaprylin) owing to the tricyclic diterpene hydrophobic structure in their molecules that enables them to adopt a unique arrangement in the fibers.     

Catalytic Selective Dihydrosilylation of Internal Alkynes Enabled by Rare-Earth Ate Complex

Hydrosilylation of alkynes generally yield vinylsilanes, which are inert to the further hydrosilylation because of the steric effects. Reported here is the first successful dihydrosilylation of aryl- and silyl-substituted internal alkynes enabled by a rare-earth ate complex to yield geminal bis- and tris(silanes), respectively. The lanthanum bis(amido) ate complex supported by an ene-diamido ligand proved to be the ideal catalyst for this unprecedented transformation, while the same series of yttrium and samarium alkyl and samarium bis(amido) ate complexes exhibited poor activity and selectivity, indicating significant effects of the ionic size and ate structure of the rare-earth catalysts.     

Amidation-Dominated Re-Assembly Strategy for Single-Atom Design/Nano-Engineering: Constructing Ni/S/C Nanotubes with Fast and Stable K-Storage

An amidation-dominated re-assembly strategy is developed to prepare uniform single atom Ni/S/C nanotubes. In this re-assembly process, a single-atom design and nano-structured engineering are realized simultaneously. Both the NiO₅ single-atom active centers and nanotube framework endow the Ni/S/C ternary composite with accelerated reaction kinetics for potassium-ion storage. Theoretical calculations and electrochemical studies prove that the atomically dispersed Ni could enhance the convention kinetics and decrease the decomposition energy barrier of the chemically-absorbed small-molecule sulfur in Ni/S/C nanotubes, thus lowering the electrode reaction overpotential and resistance remarkably. The mechanically stable nanotube framework could well accommodate the volume variation during potassiation/depotassiation process. As a result, a high K-storage capacity of 608 mAh g⁻¹ at 100 mA g⁻¹ and stable cycling capacity of 330.6 mAh g⁻¹ at 1000 mA g⁻¹ after 500 cycles are achieved.     

Homogeneous,Low-volume,Efficient, and Sensitive Quantitation of Circulating Exosomal PD-L1 for Cancer Diagnosis and Immunotherapy Response Prediction

Immunotherapy has revolutionized cancer treatment, but its efficacy is severely hindered by the lack of effective predictors. Herein, we developed a homogeneous, low-volume, efficient, and sensitive exosomal programmed death-ligand 1 (PD-L1, a type of transmembrane protein) quantitation method for cancer diagnosis and immunotherapy response prediction (HOLMES-Exo_PD-L1). The method combines a newly evolved aptamer that efficiently binds to PD-L1 with less hindrance by antigen glycosylation than antibody, and homogeneous thermophoresis with a rapid binding kinetic. As a result, HOLMES-Exo_PD-L1 is higher in sensitivity, more rapid in reaction time, and easier to operate than existing enzyme-linked immunosorbent assay (ELISA)-based methods. As a consequence of an outstanding improvement of sensitivity, the level of circulating exosomal PD-L1 detected by HOLMES-Exo_PD-L1 can effectively distinguish cancer patients from healthy volunteers, and for the first time was found to correlate positively with the metastasis of adenocarcinoma. Overall, HOLMES-Exo_PD-L1 brings a fresh approach to exosomal PD-L1 quantitation, offering unprecedented potential for early cancer diagnosis and immunotherapy response prediction.     

四卤化锰(Ⅱ)配合物的结构调控及力致发光性能

力致发光是一种力刺激诱导的发光现象。由于其独特的发光方式,使得力致发光材料在结构损伤检测、压力传感、显示和安全标记等方面展现出了巨大的应用价值。目前已报道的力致发光材料大多基于无机材料体系,而有机力致发光材料体系相对较少,并且人们对其发光机理的认识仍不清晰。在本文中,我们发现锰(Ⅱ)配合物[BPP]2[Mn Br4]具有力致发光特性,并在此基础上设计合成了一系列具有力致发光性质的四卤化锰(Ⅱ)配合物。改变有机阳离子配体或者卤素阴离子可对其光物理性质进行有效调控。固态下,这些锰(Ⅱ)配合物均显示出了较强的光致发光现象,同时表现出了明显的力致发光特性。晶体结构分析表明,分子内/分子间强的C―H…X (X=Br或Cl)相互作用对锰(Ⅱ)配合物的力致发光起到了至关重要的作用,它可在较大程度上降低由分子振动和旋转造成的能量损失。本工作将为力刺激响应型材料体系的拓展提供一定的参考价值。     

部分还原二氧化钛的NMR和EPR研究

Partially reduced TiO₂ nanomaterials have attracted significant interest because of their visible-light activity for catalysis and photodegradation. Herein, we prepared a partially reduced anatase TiO₂ (Re-A-TiO₂) nanoparticle material using a fast combustion method, demonstrating good activity toward decomposing methyl orange under visible light irradiation. The surface structure of the prepared material, after being surface-selectively ¹⁷O-labeled with H₂¹⁷O (¹⁷O-enriched water), was studied via ¹⁷O and ¹H solid-state magic angle spinning nuclear magnetic resonance (MAS NMR) spectroscopy and electron paramagnetic resonance (EPR) spectroscopy, and the obtained results were compared to those of non-reduced anatase TiO₂ (A-TiO₂). The EPR results showed that the concentrations of paramagnetic species (i.e., oxygen vacancies (OV) and Ti³⁺) in Re-A-TiO₂ were much higher than that in A-TiO₂, while the former was associated with a higher OV/Ti³⁺ ratio. The intensities of the EPR signals were significantly affected by the adsorbed water, and this phenomenon was explored in combination with ¹H NMR spectroscopy. The ¹H species on Re-A-TiO₂ appeared at larger chemical shifts, denoting the increased acidity of the sample, and these ¹H species on Re-A-TiO₂ were more difficult to remove than those on A-TiO₂. On the other hand, different features were observed for the signals arising from the two-coordinated oxygen atoms (μ₂-O) in ¹⁷O NMR, suggesting a typical anatase TiO₂(101) surface on A-TiO₂, but a more complex surface environment for Re-A-TiO₂. Furthermore, a larger amount of hydroxyl groups (OH) were observed on Re-A-TiO₂ compared to that on A-TiO₂, indicating a larger proportion of exposed (001) facets on Re-A-TiO₂. However, the μ₂-O signals broadened and became similar when the drying temperature was increased to 100 ℃, indicating a non-faceted anatase TiO₂ surface in such conditions. Based on the EPR and NMR results, a significant fraction of the OH species is believed to be formed from the reaction of the paramagnetic centers and adsorbed water molecules. The ¹H→¹⁷O cross polarization (CP) MAS and two-dimensional heteronuclear correlation (2D HETCOR) NMR spectra were used to verify the spatial proximity of the hydrogen and oxygen species, confirming the spectral assignments of a strongly adsorbed water and one type of surface OH species. In particular, the ¹H NMR signals at approximately 11 ppm were ascribed to the hydrogen species in the intramolecular hydrogen bond. In summary, this study investigated the paramagnetic species and surface structure of anatase TiO₂ materials by combining EPR along with ¹H and ¹⁷O solid-state NMR spectroscopy. The differences in the surface structures of Re-A-TiO₂ and A-TiO₂ should be closely related to their different properties toward the photodegradation of methyl orange.     

REAL‐t1, an Effective Approach for t1‐Noise Suppression in NMR Spectroscopy Based on Resampling Algorithm

Summaryof main observation and conclusionIn multidimensional(nD)NMR spectroscopy,t1noise usually appears as ridges along indirect dimen-sions,and affects observation of weak signals.The main source of t1noise is instrumental instability,which causes random variation of FID amplitude during data acquisitions and introduces random noise-like peaks into spectrum after Fourier transformation.A number of efforts have been devoted,in order to develop new method or to improve existing approaches for suppressing t1noise.Herein,we propose a novel t1noise suppression method based on resampling algorithm for data processing,shortenedas REAL-t1.The method was verified using simulated 2D spectra,and NOESY spectra of sucrose and protein GB1,showing that the spectral quality was improved in all cases.The performance of REAL-t1was also compared with another recently pro-posed method,which showed that these two methods provided similar performance while REAL-t1cost much shorter experimental time.     

Synthesis of CF2H‐Containing Oxime Ethers Derivatives from ClCF2H,tert‐Butyl Nitrile and Indoles

Summaryof main observation and conclusion A new and intriguing methodology to access various O-difluoromethylation oxime compounds from CICF2H,TBN and indoles is developed under mild reaction conditions.This strategy can suppress N-difluoromethylation of indoles successfully,in which there are two different active species(:CF2and·NO)while indoles are unprotected,featuringsimple operation and radical involvement.     

Strong and Superhydrophobic Wood with Aligned Cellulose Nanofibers as a Waterproof Structural Material†

Lightweight structural materials are important for the energy efficiency of applications, particularly those in the building sector. Here, inspired by nature, we developed a strong, superhydrophobic, yet lightweight material by simple in situ growth of nano‐SiO₂ and subsequent densification of the wood substrate. In situ generation of SiO₂ nanoparticles both inside the wood channels and on the wood surfaces gives the material superhydrophobicity, with static and dynamic contact angles of 159.4^o and 3^o, respectively. Densification of the wood to remove most of the spaces among the lumen and cell walls results in a laminated, dense structure, with aligned cellulose nanofibers, which in turn contributes to a high mechanical strength up to 384.2 MPa (7‐times higher than natural wood). Such treatment enables the strong and superhydrophobic wood (SH‐Wood) to be stable and have excellent water, acid, and alkaline resistance. The high mechanical strength of SH‐Wood combined with its excellent structural stability in harsh environments, as well its low density, positions the strong and superhydrophobic wood as a promising candidate for strong, lightweight, and durable structural materials that could potentially replace steel.     

Synthesis of core-shell structured Au@Bi2S3 nanorod and its application as DNA immobilization matrix for electrochemical biosensor construction

The core-shell structured Au@Bi2S3 nanorods have been prepared through direct in-situ growth of Bi2S3 at the surface of pre-synthesized gold nanorods.The product was characterized by X-ray diffraction,transmission electron microscopy and energy-dispersive X-ray spectroscopy.Then the obtained Au@Bi2S3 nanorods were coated onto glassy carbon electrode to act as a scaffold for fabrication of electrochemical DNA biosensor on the basis of the coordination of-NH2 modified on 5’-end of probe DNA and Au@Bi2S3.Electrochemical characterization assays demonstrate that the Au@Bi2S3 nanorods behave as an excellent electronic transport channel to promote the electron transfer kinetics and increase the effective surface area by their nanosize effect.The hybridization experiments reveal that the Au@Bi2S3 matrix-based DNA biosensor is capable of recognizing complementary DNA over a wide concentration ranging from 10 fmol/L to 1 nmol/L.The limit of detection was estimated to be 2 fmol/L(S/N=3).The biosensor also presents remarkable selectivity to distinguish fully complementa ry sequences from basemismatched and non-complementary ones,showing great promising in practical application.