Chemical Science
·
2021
·Vol. 12
·期 15
·5631-5637
·
IF 9.825
Qiujian Xie,Yumin Yang,Weijie Zhang,Zhu Gao,Xiaofeng Li,Juntao Tang,Chunyue Pan,Guipeng Yu
Conjugated microporous polymers (CMPs) are cost-effective photocatalysts in organic transformations, while they are usually limited by the insufficient separation of photogenerated charges. Here we report a polarization strategy through molecular geometry optimization to promote the charge separation of CMPs. Three CMP photocatalysts with an alternative donor–acceptor skeleton and tunable symmetry were synthesized by the oxidative coupling of bis-carbazoles with electron-deficient bridges (benzene/pyridine/pyrimidine). Simply regulating the polarization of the starting monomers leads to tailorable porosity, photoelectric properties, and photocatalytic activity of the CMPs. They exhibited high efficiency in C-3 selenocyanation of indoles under visible-light and at room temperature, and pyridine-based CMPs with the largest dipole moment gave a yield of up to 94%, superior to their state-of-the-art photocatalyst counterparts. Photo-physical experiments combined with theoretical calculations further supported that the incorporation of the polarized linker introduced an internal electric field, benefitting efficient charge separation. This offered new insight into developing high-performance photocatalysts.
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APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY
·
2023
·
IF 3
Sun Ziyi,Zhang Gaoning,Li Xiaoru,Cui Qingqi,Gong Lili,Tian Zhenhua
This study investigated the chemical and volatile characteristics of sea buckthorn fruits from three different regions in China. The chemical composition of the volatile oil was determined by using a non-targeted gas chromatography and mass spectrometry (GC/MS) method and the differences in chemical composition among the three producing areas were compared by heatmap providing a visual basis for researchers. A total of 93 compounds were identified, including 52 compounds from the Northeast China, 51 from the Xinjiang region, and 37 from Inner Mongolia region. Then, the in vitro antioxidant activity of sea buckthorn fruit oil was measured using DPPH, ABTS, and SOD inhibition tests, and the results showed that sea buckthorn fruit oil in northeast China was the strongest antioxidant, followed by Inner Mongolia and Xinjiang. The results of the CCK-8 experiment indicated that within the tested concentration, there is no cell cytotoxicity of the essential oil in human umbilical vein endothelial cells (HUVECs) cells. The results could supply reference to distinguish sea buckthorn fruit from different production areas and, meanwhile, clarify the activity and safety of sea buckthorn oil.
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CARBON
·
2023
·
IF 10.9
Bin Wang,Shizhen Dong,Xiaojuan Wu,Yanling Yu,Nuoxin Wang,Jinyang Li,Zuowan Zhou
Poly (3-aminophenylboronic acid) is an important boronic acid-based functional polymer, but its synthesis is difficult owing to the boronic acid group in 3-aminophenylboronic acid (ABA) has a strong electron-withdrawing effect. A topologically defective carbon-based catalyst with nanotubular morphology is developed by ammonia-assisted atomic imprinting and applied to facilitate the polymerization of ABA. Catalytic experiments show that the catalyst can greatly increase the polymerization rate of ABA and also significantly improve the quality of the polymer. The study of catalytic mechanism reveals the interaction between ABA (and its derivatives) and various structures of the catalyst, including electron-transfer-based interactions between ABA and topological defects as well as spatial confinement effects between ABA and nanospace structures. Under the combined influence of the above effects, ABA achieves efficient polymerization centered on topological defects. Consequently, this study demonstrates a carbon-based catalytic system that can efficiently promote the chemical oxidative polymerization of ABA.
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INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2023
·
IF 8.2
Xian He,Wanshui Yang,Qihong Zhao,Xinsheng Qin
In this study, we prepared Pickering emulsions stabilized by quinoa protein isolate (QPI) and (-)-epigallocatechin-3-gallate (EGCG) non-covalent hybrid particles using ultrasonic emulsification technique and demonstrated lipid oxidation and in vitro digestion process of Pickering emulsions. The interaction forces between QPI and EGCG were characterized using fluorescence spectroscopy, isothermal titration calorimetry, and Fourier transform infrared spectroscopy. Results indicated that the non-covalent QPI/EGCG hybrid particles were formed mainly via hydrophobic interactions, hydrogen bonds, and electrostatic interactions at pH 5. Then, the QPI/EGCG non-covalent hybrid particles were applied to modify the Pickering emulsion with ultrasonic homogenization. The rheological experimental results showed that the energy storage modulus (G′) was higher than the loss modulus (G″), indicating that the emulsion had solid-like properties. As a physical barrier, interfacial layer fabricated by antioxidant QPI/EGCG hybrid particles limited lipid oxidation at 60 °C for 15 days. At 37 °C, the QPI/EGCG hybrid particles stabilized Pickering emulsions with robust antioxidant interfacial structure limited the lipid digestion under simulated gastrointestinal tract (gastric, small intestine phases). Thus, EGCG and quinoa proteins were more resistant to free radical oxidation and gastrointestinal digestion with the assistance of ultrasound. It provides a basis for better development of food and drug delivery systems by fully utilizing the antioxidant properties of plant polyphenols.
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iScience
·
2024
·
IF 4.6
Xiaoyin Rong,Ruixiao Li,Tianye Gong,Haonan Li,Xiaolei Zhao,Guoqing Cao,Meng Li,Bugao Li,Yang Yang,Xiaohong Guo
Circular RNA is a special category of non-coding RNA that has emerged as epigenetic regulator of adipose tissue development. However, the mechanism governing intramuscular adipogenesis of circRNA remains largely uncharted. In this study, circMEF2C(2, 3), looped by MEF2C exons 2 and 3, was identified from the pig MEF2C gene. Expression of circMEF2C(2, 3) is upregulated in early stage of intramuscular adipogenesis and muscular tissue of lean pigs (DLY pig). Subsequently, overexpression or knockdown of circMEF2C(2, 3) reflected that it participates in promoting proliferation and inhibiting adipogenic differentiation in porcine intramuscular preadipocytes and murine C3H10T1/2 cells. Mechanically, circMEF2C(2, 3) competitively combined with miR-383 and miR-671-3p to the 3′-UTR of MEF2C , which maintains MEF2C expression in regulating proliferation and adipogenesis. In summary, circMEF2C(2, 3) is a key regulator in the proliferation and adipogenic differentiation of intramuscular adipogenesis, suggesting its potential as a multi-target strategy for adipose development and associated diseases.
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JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
·
2023
·
IF 6.1
Zonghan Wang,Fawen Yin,Deyang Li,Xinmiao Wang,Chao Guo,Donghong Liu,Beiwei Zhu,Dayong Zhou
Catechins are widely recognized for superb antioxidant capability, but their application as food antioxidants is hindered by susceptibility to auto-browning under high-moisture conditions. Here, we proposed a strategy of ordered encapsulation with cyclodextrin-based metal–organic frameworks (CD-MOFs) to alleviate the auto-browning phenomenon of catechins while preserving their antioxidant capability and demonstrated the feasibility of this strategy via selecting epigallocatechin-3-gallate (EGCG) as a model. Even in aqueous solutions, EGCG@CD-MOFs still possessed delayed browning, in contrast with pristine EGCG, characterized by suppressed efficiencies on the generation of oxidative dimers (theasinensin A) and semiquinone radicals. Mechanism insights revealed that ordered encapsulation brought dual regulations on the self-aggregation behavior of EGCG: EGCG@CD-MOFs exhibited a gradual structural collapse from the framework toward irregular aggregates as O–K bonds broke progressively, which restricted molecular mobility of EGCG, and EGCG molecular conformations became constrained by the structure of EGCG@CD-MOFs as well as rich intermolecular forces, even after structural collapse.
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MICROCHEMICAL JOURNAL
·
2023
·
IF 4.8
Sisi He,Yiyi Liu,Chaoxian Chi,Dongdong Zhou,Chuan-Fan Ding,Xucong Lin,Jiabin Wang,Fangling Wu
The differentiation of 3-AminoPyrrolidine (3AP) and its derivative isomers is significant due to their use as intermediates in drug synthesis. However, the separation of these isomers, which exhibit both chiral and positional isomerism, has consistently posed challenges. In this study, an efficient analytical method was developed to discrimination between the four isomers of R/S-I/N-Boc-3-AminoPyrrolidine (R/S-l/N-Boc-3AP) and four groups of derived chiral isomers, namely R/S-N-Methyl-3-AminoPyrrolidine (R/S-N-Me-3AP), R/S-N-Ethyl-3-AminoPyrrolidine (R/S-N-Et-3AP), R/S-1-Bzl-3-AminoPyrrolidine (R/S-1-Bzl-3AP), and R/S-1-Cbz-3-AminoPyrrolidine (R/S-1-Cbz-3AP). The discrimination was achieved by utilizing natamycin (Nat) as a differentiation agent and 2/3/4-aminobenzenesulphonic acid (2/3/4-ABSA) as ligand. The facile discrimination of the four positional isomers of R/S-1-Boc-3AP and R/S-N-Boc-3AP was achieved using ion mobility spectrometry (IMS) based on their formed diastereomeric complexes [Nat + (Boc-3AP) 2 + (2-ABSA) 2 + H] + . The isomers were also studied via tandem mass spectrometry (MS/MS) using the formed ternary complexes, different fragment ions were observed for l-Boc-3AP and N-Boc-3AP, but the R/S enantiomers cannot be discriminated either. In addition, the enantiomers R/S-l-Bzl-3AP and R/S-l-Cbz-3AP were differentiated based on mobility using [Nat + (R/S-l-Bzl-3AP) + (3-ABSA) 2 + H] + and [Nat + (R/S-l-Cbz-3AP) + 2-ABSA + H] + ; however for the small enantiomeric molecules of R/S-N-Me-3AP and R/S-N-Et-3AP, chiral discrimination was not achieved via the ternary complexes of Nat + R/S-N-Me-3AP-ABSA and Nat + R/S-N-Et-3AP-ABSA. Importantly, the separation was greatly improved by the coordinated alkali metal ions, where the separation resolution (R p-p ) increased with the radius of the metal ions. Finally, quantitative analysis and method validation were carried out for the four Boc-3AP isomers using both MS/MS and IMS-MS. Overall, the proposed method opens possibilities for the rapid discrimination and quantification of isomers exhibiting both chiral and positional isomerism in MS/MS and IMS-MS analyses.
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Materials Today Chemistry
·
2023
·
IF 7.3
Shiwei Feng,Chengping Zhang,Hengdao Quan
A facile, safe, and environmentally friendly preparation method is described for the synthesis of AlF x (OH) 3-x by the activation of γ-Al 2 O 3 using HCFO-1233zd( E ) under various temperatures. Comprehensive characterization techniques including XRD , XPS, N 2 sorption, SEM, TEM , 27 Al MAS NMR, FTIR, and py-IR were employed, revealing that at lower temperatures such as 275 °C and 300 °C, the synthesis yielded AlF(OH) 2 , while at higher temperatures like 350 °C and 375 °C, pyrochlore AlF 1.5 (OH) 1.5 and metastable hexagonal tungsten bronze-type (HTB) β-AlF 3 were formed, with α-AlF 3 detected at 325 °C. Notably, a significant quantity of AlF(OH) 2 can be obtained at 325 °C within a specific time frame. This amorphous phase exhibits weak Lewis acid sites and a lower acid density, rendering it significantly more effective in the isomerization of HCFO-1233zd( E ) compared to strong Lewis acid catalysts such as AlF 1.5 (OH) 1.5 and β-AlF 3 , which could promote coke formation, leading to catalyst deactivation . Moreover, due to its limited further fluorination at 290 °C, the optimal catalyst exhibits prolonged lifespan and high efficiency in HCFO-1233zd( E ) isomerization.
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CERAMICS INTERNATIONAL
·
2023
·
IF 5.2
Lei Xiao,Qiang Li,Lianwen Deng,Sen Peng,Tulin Yi,Weichun Liu
Ba 1- x K x (Zn 1/3 Nb 2/3 )O 3- x /2 (BKZN, x = 0–0.2) ceramics were prepared by the high-temperature solid-state reaction method. Based on P–V–L theory, Raman vibration spectroscopy and X-ray photoelectron spectroscopy (XPS), this paper investigates the relationship between the internal and external factors of K + substitution in the Ba(Zn 1/3 Nb 2/3 )O 3 (BZN) ceramics and the microwave dielectric properties of the ceramics. X-ray diffraction (XRD) characterisation revealed that all samples were single phase with no impure phases. Replacing Ba 2+ with K + greatly reduced the sintering temperature and optimised the microwave dielectric properties of the ceramics. The dielectric constant ( ε r ) was closely related to the ion polarizability and density, and inversely proportional to Raman shift of the A 1g (O) peak. The quality factor ( Q × f ) depended largely on the lattice energy ( U b ) and the full width at half-maximum (FWHM) of A 1g (O) near 790 cm −1 . The temperature coefficient of the resonance frequency ( τ f ) could be inferred from the bond energy ( E b ) and oxygen octahedral distortion. Finally, outstanding microwave dielectric properties ( ε r = 40.83, Q × f = 71,658 GHz and τ f = 2.52 ppm/°C) were acquired for Ba 0.95 K 0.05 (Zn 1/3 Nb 2/3 )O 2.975 ceramics sintered at the optimum sintering temperature (1325 °C) for 4 h.
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SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
·
2023
·
IF 4.4
Huimin Zhou,Anni Zhu,Caiyin Wang,Xiaoyu Guo,Ye Ying,Yiping Wu,Xinling Liu,Feng Wang,Ying Wen,Haifeng Yang
5-Hydroxyindole-3-acetic acid (5-HIAA) is regarded as a biomarker for diagnosis of carcinoid tumors, and it is of great significance to developing a precision assay for monitoring 5-HIAA levels. In this work, gold nanoparticles loading on the surface of MOF-199 (Au NPs/MOF-199) is prepared to propose a surface enhanced Raman scattering (SERS) assay for 5-HIAA. When 4-mercaptopyridine (4-MPy) is used as a SERS probe, on Au NPs/MOF-199, limit of detection (LOD) at 10 −9 mol/L can be achieved. In addition, Au NPs/MOF-199 substrate with good preparation reproducibility shows long-term storage stability at 4 °C. Under optimal condition, the Au NPs/MOF-199-based SERS method is applied to determine 5-HIAA in serum. The concentration linear range is from 10 −9 to 10 −5 mol/L and LOD is of 6.40 × 10 −11 mol/L. Much importantly, Au NPs/MOF-199 substrate exhibits specific response toward 5-HIAA against other metabolites in the serum due to the capturing selectivity from porous MOF-199. The recoveries obtained on spiked human serum samples locate in the span from 94.30% to 106.00% with RSD of 4.01–7.43%. Au NPs/MOF-199-based SERS sensing strategy is a promising avenue for on-field monitoring biomedical species for clinic diagnosis purpose.
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Science China-Materials
·
2023
·Vol. 66
·期 9
·3415-3423
·
IF 8.1
Gao Jinxiang,Che Bo,Cai Huiling,Xiao Peng,Zhang Lijian,Cai Zhiyuan,Zhu Changfei,Tang Rongfeng,Chen Tao
Antimony selenosulfide (Sb 2 (S,Se) 3 ) is a promising photovoltaic material because of its high chemical stability, optimal optoelectronic properties, and low-cost advantages. However, finding suitable material processing approaches to obtain elemental controlled Sb 2 (S,Se) 3 films with suppressed deep-level defects poses fundamental demands and challenges to developing this emerging solar technology. Here, we developed a robust method for tailoring the composition of the film through controlling the anion elements. The films were prepared by evaporating the presintered Sb 2 (S,Se) 3 alloy compound via a single-source thermal evaporation process. A quasi-precise estimate of single-phase Sb 2 (S,Se) 3 films was made by sintering Sb, S, and Se elemental precursors and adjusting the anion molar ratio in the prefabricated Sb 2 (S,Se) 3 alloy compound, and the elemental ratio of the precursor alloy compound was maintained in the as-obtained Sb 2 (S,Se) 3 films. A highly efficient Sb 2 (S,Se) 3 solar cell with a power conversion efficiency of 8.25% was achieved by introducing low-cost CuPc-doped P3HT as a hole-transporting layer. Here, we demonstrate the dependence of deep-level defects and oriented crystal growth on the S/Se atomic ratios and show how tunability can be used to improve carrier transport for photovoltaic energy conversion. Our study presents a novel approach to fabricating metal chalcogenide semiconducting films and improving the performance of Sb 2 (S,Se) 3 solar cells.
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MICROCHEMICAL JOURNAL
·
2023
·
IF 4.8
Jia Liu,Bin Yang,Yuting Wang,Fengming Zhang,Xin Liu,Shiyue Niu,Yue Yuan,Shuyun Bi
Cadmium sulfide quantum dots (CdS QDs) were synthesized with 3-mercaptopropionic acid (MPA) as protective agent, which were characterized by TEM, UV–vis, fluorescence, XRD and TGA. Based on the fluorescence quenching of 3-MPA-CdS QDs, the indirect methods for the determination of furazolidone (FZD) and nitrofurantoin (NFT) were established. The interaction between FZD/NFT and CdS QDs was investigated by using fluorescence, resonance light scattering, UV–vis and FT-IR. The analyses of Stern-Volmer and fluorescence lifetime indicated that the two quenching systems were all static. The binding constant ( K a ) of FZD/NFT-CdS QDs was 1.20 × 10 4 /1.81 × 10 4 L/mol at 293 K, respectively. Hydrogen bond or van der Waals force was the main binding force between CdS QDs and drugs. Under optimum experimental conditions, the concentration of FZD/NFT was respectively highly correlated with the fluorescence intensity ratio in the range of 0.27 – 36.03/0.57 – 28.58 μg mL −1 . The interference experiments showed that the methods had good selectivity. The limit of detection (LOD) for FZD/NFT was 0.02/0.01 μg mL −1 . The contents of FZD and NFT in fish samples were determined, and the recoveries were 97.41–99.52 % and 96.64–100.49 %, respectively.
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危险品化学品经营许可证（带存储）