TETRAHEDRON LETTERS
·
2018
·
IF 2.125
Rongxing Zhang,Shengzhou Jin,Yuanxing Wan,Sen Lin,Zhaohua Yan
A novel, efficient, and green protocol to construct C–S bond has been developed via HBr/H 2 O 2 -mediated sulfenylation of styrenes and 4-hydroxycoumarins leading to unsymmetrical sulfides. Various unsymmetrical sulfides were prepared in one step with moderate to good yields using environmentally-friendly H 2 O 2 as oxidant and HBr as catalyst. Based on the preliminary experimental results, a plausible reaction mechanism was proposed for HBr/H 2 O 2 -mediated formation of C–S bond with thiosulfates .
研究领域:
有机化学
·
绿色化学
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DOI
高影响因子
OPTICAL MATERIALS
·
2021
·
IF 3.08
Rui Qu,Mingyang Gao,Haonan Li,Xiaofei Qi,Cheng Liu,Wu Zhao,Junfeng Yan,Zhiyong Zhang
Formamidinium lead bromide perovskite (FAPbBr 3 ) nanostructures have aroused increasing attention considering their excellent optoelectronic performance and higher stability than their MA- and Cs-based counterparts. Herein, we synthesized size-tunable FAPbBr 3 quantum dots (QDs) at room temperature. The size of the perovskite QDs could be ajusted from 5.4 to 2.3 nm by just varying the amount of Hydrobromic Acid (HBr) added into the precursor. As a result, the photoluminescence (PL) emissions exhibited large blueshift from 531 to 446 nm due to quantum confinement effect. Quantum mechanical calculations of the optical gap fitted well with the experimental results. We found that the addition of HBr not only increased the concentration of the Br − but also protonated the oleylamine ligands. The two events synergically governed the size-decreasing effect of the QDs with increasing amount of HBr. The size-tunable FAPbBr 3 QDs showed great application prospect in the field of photoelectric devices.
研究领域:
材料科学
·
光学
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产品关联
DOI
高影响因子
JOURNAL OF BIOTECHNOLOGY
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2015
·
IF 2.871
Yue-De Cao,Yu-Cai He,Hao Li,Guo-Yin Kai,Jian-He Xu,Hui-Lei Yu
Hyoscyamine 6 β -hydroxylase (H6H, EC 1.14.11.11), an α-ketoglutarate dependent dioxygenase catalyzes the hydroxylation of (−)-hyoscyamine and the subsequent epoxidation of 6 β -hydroxyhyoscyamine to form scopolamine, a valuable natural alkaloid. In this study, random mutagenesis and site-directed saturation mutagenesis were used to enhance the hydroxylation activity of H6H from Anisodus acutangulus ( Aa H6H). A double mutant, Aa H6H M1 (S14P/K97A), showed a 3.4-fold improved hydroxylation activity compared with the wild-type enzyme, and the in vivo epoxidation activity was also improved by 2.3 times. After 34 h cultivation of Escherichia coli cells harboring Aa h6h m1 in a 5-L bioreactor with a working volume of 3 L, scopolamine was produced via a single-enzyme-mediated two-step transformation from 500 mg L −1 (−)-hyoscyamine in 97% conversion, and 1.068 g of the product were isolated, corresponding to a space-time yield of 251 mg L −1 d −1 . This study shows that the protein engineering of some key enzymes is a promising and effective way for improving the production of rare natural products such as scopolamine.
研究领域:
生物化学
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生物技术
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微生物学
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酶学
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产品关联
DOI
PubMed
高影响因子
Analytical Methods
·
2023
·Vol. 15
·期 36
·4663-4673
·
IF 3.1
Fanying Deng,Fuxia Zhao,Wenhui Wang,Shiqi Liu,Yan Wang
Memory disorder (MD) is a neurodegenerative disease that seriously affects the quality of life of the elderly in China. It is characterized by cognitive deficits and psychiatric symptoms. In addition to oxidative damage, neurotransmitter disorders, and other factors, Ca2+ homeostasis and lipid metabolism are among the major pathways of MD etiology. Studies have shown that Ca2+ influx, causing Ca2+ overload, leads to neuronal apoptosis and alterations in lipid metabolites at all MD stages. Qifu decoction (QFD) is one of the classic compounds for the traditional treatment of dementia, which has been shown to significantly improve MD caused by dementia and Alzheimer's disease (AD). So far, it is not clear whether QFD can regulate Ca2+ homeostasis and lipids to improve MD. In this study, we developed a scopolamine hydrobromide MD mouse model and performed neurobehavioral experiments and examinations of brain tissue pathology, Ca2+ homeostasis-related factor levels, and non-targeted lipidomics to explore the mechanism of QFD action in improving MD. The results showed that four weeks of intragastric administration of QFD resulted in significant increases in the cognitive ability and spatial memory ability of the mice with MD. Furthermore, the damage to nerve cells was reduced, the levels of Ca2+ and CaM in the serum were decreased, whereas the content of CaMKII was increased, and the Ca2+ homeostasis was regulated. Non-targeted lipidomics detected four lipid subclasses and 17 potential differential metabolites. Metabolic pathway analysis revealed that QFD significantly regulated sphingolipid metabolism and improved MD. In summary, QFD improves scopolamine hydrobromide memory impairment in mice by regulating the Ca2+ signaling pathway and sphingolipid metabolism. This study provides new insights into the beneficial mechanism of QFD on MD from the perspective of lipidomics.
研究领域:
神经科学
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药理学
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中医
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脂质组学
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神经退行性疾病
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DOI
高影响因子
BMC Chemistry
·
2024
·Vol. 18
·期 1
·1-15
·
IF 4.3
Huang Xiaomin,Wang Ting,Wang Ludan,Sun Yantao,Zhang Ziru,Zhang Yajun
In the investigation of active ingredients from natural products, current technologies relying on drug–target affinity recognition analysis face significant challenges. This is primarily due to their limited specificity and inability to provide downstream pharmacodynamic information, such as agonistic or antagonistic activity. In this study, a two-point method was developed by immobilizing M3 acetylcholine receptor (M3R) through the combination of the conformation-specific peptide BJ-PRO-13a and the HaloTag trap system. We systematically assessed the specificity of the immobilized M3R using known M3R antagonists (pirenzepine and atropine) and agonists (cevimeline and pilocarpine). By frontal analysis and nonlinear chromatography, the performance of immobilized M3R was evaluated in terms of binding kinetics and thermodynamics of four drugs to the immobilized M3R. Additionally, we successfully identified two M3R antagonists within an extract from Daturae Flos (DF), specifically hyoscyamine and scopolamine. Our findings demonstrate that this immobilization method effectively captures receptor-ligand binding interactions and can discern receptor agonists from antagonists. This innovation enhances the efficiency of receptor chromatography to determine binding-affinity in the development of new drugs, offering promise for the screening and characterization of active compounds, particularly within complex natural products.
研究领域:
药理学
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分析化学
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天然产物研究
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产品关联
DOI
PubMed
高影响因子
Advanced Science
·
2024
·
IF 14.3
Guangman Cui,Shaohui Deng,Biao Zhang,Manchun Wang,Zhousheng Lin,Xinyue Lan,Zelong Li,Guangyu Yao,Meng Yu,Jun Yan
The extracellular matrix (ECM) is critical for drug resistance in colorectal cancer (CRC). The abundant collagen within the ECM significantly influences tumor progression and matrix-mediated drug resistance (MMDR) by binding to discoidin domain receptor 1 (DDR1), but the specific mechanisms by which tumor cells modulate ECM via DDR1 and ultimately regulate TME remain poorly understand. Furthermore, overcoming drug resistance by modulating the tumor ECM remains a challenge in CRC treatment. In this study, a novel mechanism is elucidated by which DDR1 mediates the interactions between tumor cells and collagen, enhances collagen barriers, inhibits immune infiltration, promotes drug efflux, and leads to MMDR in CRC. To address this issue, a multistage drug delivery system carrying DDR1-siRNA and chemotherapeutic agents is employed to disrupt collagen barriers by silencing DDR1 in tumor, enhancing chemotherapy drugs diffusion and facilitating immune infiltration. These findings not only revealed a novel role for collagen-rich matrix mediated by DDR1 in tumor resistance, but also introduced a promising CRC treatment strategy.
研究领域:
肿瘤学
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药学
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生物医学工程
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分子生物学
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产品关联
DOI
PubMed
高影响因子
Small
·
2025
·
IF 12.1
Lijun Xu,Daohua Wang,Huang Ye,Hang Li,Chengshu Zhang,Qianwen Guan,Haiqing Zhong,Zhangtong Han,Junhua Luo
Organic–inorganic hybrid perovskites (OIHPs) have shown great potential for direct X-ray detection in security screening and medical diagnostics. However, their humidity stability is compromised due to the susceptibility of the structural components to water molecules, thereby limiting their practical application. In this work, stable and sensitive X-ray detection is achieved using high-quality bulk single crystals of the 3D perovskitoid (DMPZ)Pb 2 Br 6 ( DPB , DMPZ = N , N ′-dimethyl-pyrazinium), wherein N -acid protons are replaced with hydrophobic alkyl groups. Notably, the crystals maintain phase stability after 60 days of immersion in water at room temperature, demonstrating their significant potential for moisture-stable X-ray detectors. Based on the bulk crystals of DPB , the X-ray detectors are successfully fabricated, achieving a high sensitivity of 6437.2 µC Gy air −1 cm −2 at 70 V bias and a detection limit low to 46.7 nGy air s −1 , outperforming most low-dimensional perovskite detectors. Most strikingly, the detectors retain 79.6% of their initial sensitivity after 14 days of water immersion, highlighting exceptional moisture stability. This work is the first to construct moisture-stable high-performance X-ray detectors using 3D perovskitoid single crystals, advancing the development of stable X-ray detection.
研究领域:
材料科学
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医学影像
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辐射探测技术
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产品关联
DOI
PubMed
高影响因子
ORGANIC ELECTRONICS
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2025
·
IF 2.6
Zimu Li,Chunli Jiang,Chunhua Luo,Hechun Lin,Xiaodong Tang,Hui Peng
To address the challenges posed by the rapid development of artificial intelligence and big data, various artificial synaptic devices have been developed to overcome the limitations of traditional computing systems. In this study, a two-terminal device using a conducting polymer, poly(hexylthiophene) (P3HT), and a molecular ferroelectric, diisopropylammonium bromide (DIPAB), is fabricated. The incorporation of the ferroelectric layer not only establishes an energy barrier for charge carriers generated by light pulses in the P3HT layer but also allows the device's response to be modulated by altering the ferroelectric polarization state of DIPAB. This device successfully simulates some basic biological synaptic functions by modulating light stimuli. Furthermore, the light logic functions of “AND” and “OR” are realized by using light pulses with different wavelengths, as well as the simulation of associative learning. The device is used to recognize MNIST handwritten digits based on a convolutional neural network (CNN), achieving a recognition accuracy of over 90 %. These results highlight the device's potential for neuromorphic computing.
研究领域:
材料科学
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神经科学
·
计算机科学
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产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2025
·
IF 6.3
Shuang Chen,Qiule Zhao,Yangchun Mo,Xiaopeng Wei,Jilin Wang,Guoyuan Zheng,Fei Long
Organic-inorganic hybrid perovskites have attracted wide attention because of their low cost, high photoelectric conversion efficiency and simple production process. Diisopropylamine was innovatively employed, in this paper, as the A-site organic ligand for bismuth-based halide organic-inorganic hybrid crystals. [(CH 3 CH 2 CH 2 ) 2 NH 2 ] a Bi b X c (X = Cl, Br and I) crystals were synthesized by a solvent evaporation method. All three crystals belong to the P2 1 /n space group. Among them, [(CH 3 CH 2 CH 2 ) 2 NH 2 ]BiBr 4 and [(CH 3 CH 2 CH 2 ) 2 NH 2 ]BiI 4 have one-dimensional chain structures, and [(CH 3 CH 2 CH 2 ) 2 NH 2 ] 2 Bi 2 Cl 8 belongs to a zero-dimensional structure. The band gap can be adjusted between 3.04 eV and 1.61 eV by the properties of halide ligands, and the good thermal stability of the three crystals are 203°C, 258°C and 291°C. Moreover, [(CH 3 CH 2 CH 2 ) 2 NH 2 ]BiI 4 thin films were prepared by the one-step solution spin-coating as a light absorbing layer. The band gap of thin films is 1.97 eV. The maximum power conversion efficiency of the device is 0.0271 %. Therefore, this organic-inorganic hybrid compound with a suitable band gap and high stability is expected to become a potential candidate material for photoelectric devices.
研究领域:
材料科学
·
化学
·
光电材料
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产品关联
DOI
高影响因子
Journal of Energy Chemistry
·
2025
·
IF 14.9
Xiaozhen Huang,Zilong Zhang,Yuheng Li,Liangliang Zhang,Can Wang,Lusheng Liang,Chi Li,Chunming Liu,Zhehong Zhou,Ruidan Zhang,Yue Wang,Mingwei An,Yang Wang,Peng Gao
Exploring multifunctional interfacial modifiers is an effective approach to addressing interface issues in perovskite solar cells (PSCs) and improving device performance and stability. While most interfacial modifiers focus on passivating defects at the interfaces, there has been limited investigation into the relationship between molecular design and interfacial charge dynamics. This work introduces resonance molecules with a push-pull effect for interfacial modification, allowing for synergistic regulation of passivation effects and charge dynamics. Specifically, FCz-PO, which includes an electron-withdrawing fluorine atom, exhibits superior passivation but poor molecular stacking and charge extraction. In contrast, MCz-PO, featuring an electron-donating methoxy group, provides effective passivation, well-ordered molecular packing, and efficient charge extraction and transport. Consequently, PSCs using MCz-PO achieve high power conversion efficiency (PCE) of 24.74% and excellent operational stability. This study suggests that resonance structures can be an effective molecular design strategy for developing interfacial modifiers with both strong passivation capabilities and well-regulated charge dynamics.
研究领域:
材料科学
·
光伏技术
·
化学工程
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产品关联
DOI
高影响因子
ADVANCED MATERIALS
·
2025
·
IF 26.8
Jingwen Yao,Yuling Huang,Haifeng Sun,Zhiyu Wang,Jie Xue,Zhifeng Huang,Shou-Cheng Dong,Xihan Chen,Haipeng Lu
Spin light-emitting diodes (spin-LEDs) are important for spin-based electronic circuits as they convert the carrier spin information to optical polarization. Recently, chiral-induced spin selectivity (CISS) has emerged as a new paradigm to enable spin-LED as it does not require any magnetic components and operates at room temperature. However, CISS-enabled spin-LED with tunable wavelengths ranging from red to near-infrared (NIR) has yet to be demonstrated. Here, chiral quasi-2D perovskites are developed to fabricate efficient spin-LEDs with tunable wavelengths from red to NIR region by tuning the halide composition. The optimized chiral perovskite films exhibit efficient circularly polarized luminescence from 675 to 788 nm, with a photoluminescence quantum yield (PLQY) exceeding 86% and a dissymmetry factor ( g lum ) ranging from 8.5 × 10 −3 to 2.6 × 10 −2 . More importantly, direct circularly polarized electroluminescence (CPEL) is achieved at room temperature in spin-LEDs. This work demonstrated efficient red and NIR spin-LEDs with the highest external quantum efficiency (EQE) reaching 12.4% and the electroluminescence (EL) dissymmetry factors ( g EL ) ranging from 3.7 × 10 −3 to 1.48 × 10 −2 at room temperature. The composition-dependent CPEL performance is further attributed to the prolonged spin lifetime as revealed by ultrafast transient absorption spectroscopy.
研究领域:
材料科学
·
光学工程
·
半导体物理
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产品关联
DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
·
2025
·
IF 8.2
Qi Gu,Kefan Chen,Xiong Zhang,Shuaihua Wang,Shaofan Wu,Wanxia Huang
Chiral two-dimensional perovskites are a promising candidate for circularly polarized light (CPL) detection, which combine inherent chirality with excellent optoelectronic properties, while exhibiting good structural stability. In this paper, a pair of chiral two-dimensional perovskites, single-crystal R/S-(BrBA)2PbBr4 are synthesized using a cooling crystallization solution method. Due to the introduction of chiral organic molecules, the inorganic layers undergo significant distortion and deformation. The large optical bandgap of the materials and the vertically oriented electrode structure of the detector result in an extremely low dark current, combined with circular dichroism (CD) spectroscopy and a photocurrent anisotropy factor of 0.14 at 405 nm, and demonstrate the good potential of the materials for detecting circularly polarized light in the ultraviolet band. In addition, the unique semiconductor properties enable it to have a detection sensitivity of 531.33 μC Gy–1 cm–2 (at 0.15 V/μm) and a detection limit of less than 100 nGy s–1 in X-ray detection, which is far lower than that of requirements in conventional medical diagnosis (5.5 μGy s–1). The final imaging experiments have also verified its feasibility for application in X-ray imaging.
研究领域:
材料科学
·
光学
·
医学成像
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产品关联
DOI
PubMed
高影响因子
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