Journal of Molecular Structure最新文献_第5页

Synthesis and characterization of novel high-oil-absorbing resin based on spherical nanocrystal cellulose 基于球形纳米晶纤维素的新型高吸油树脂的合成与表征

IF 4 2区化学 Q2 CHEMISTRY, PHYSICAL

Journal of Molecular Structure

Pub Date : 2024-11-08 DOI: 10.1016/j.molstruc.2024.140622

Enfa Fu , Lei He , Jie Chao , Xiande Dai

High-oil-absorbing resin is one of new self-swelling oil-absorbing materials, which can be used to effectively solve oil-spill problems. In this study, spherical nanocrystalline cellulose (SNC) was successfully prepared by the hydrolysis of microcrystalline cellulose, then SNC was grafted with MA and MMA to prepare novel high-oil-absorbing resin SNC-g-P(MA-co-PMMA). The structure, surface morphology, oil absorbency and thermal behavior of the resins were in-depth characterized. Furthermore, the effects of different reaction factors were studied to obtain optimized reaction conditions. The maximum oil absorbency (8.5 g/g) for SNC-g-P(MA-co-MMA) was achieved by optimizing the reaction conditions. And it exhibits higher thermal stability. Moreover, the first-order kinetic model is more appropriate to discuss the oil-absorbing kinetics of SNC-g-P(MA-co-PMMA), suggesting that the oil-absorbing process is mainly determined by the diffusion of oil molecules on the surface. Compared with reported previous research, outstanding oil-absorbing performance and higher thermal stability of SNC-g-P(MA-co-PMMA) are due to larger specific surface area and effective network volume after the introduction SNC. Benefiting from cheap raw materials (cellulose) and simple manufacturing process, the proposed approach can contribute to the mass manufacturing of cheap high-oil-absorbing resin products with excellent oil absorbency, and it is useful for oil pollution treatment.

高吸油树脂是一种新型自溶胀吸油材料，可用于有效解决溢油问题。本研究通过水解微晶纤维素成功制备了球形纳米晶纤维素（SNC），然后将 SNC 与 MA 和 MMA 接枝，制备了新型高吸油树脂 SNC-g-P(MA-co-PMMA)。对树脂的结构、表面形貌、吸油性和热行为进行了深入研究。此外，还研究了不同反应因素的影响，以获得最佳反应条件。通过优化反应条件，SNC-g-P(MA-co-MMA) 的吸油率达到了最大值（8.5 g/g）。它还表现出更高的热稳定性。此外，一阶动力学模型更适合讨论 SNC-g-P(MA-co-PMMA)的吸油动力学，表明吸油过程主要由表面油分子的扩散决定。与之前的研究相比，SNC-g-P(MA-co-PMMA)具有出色的吸油性能和更高的热稳定性，这是因为引入 SNC 后，其比表面积和有效网络体积更大。得益于廉价的原材料（纤维素）和简单的制造工艺，所提出的方法有助于大规模制造具有优异吸油性的廉价高吸油树脂产品，并可用于油污染处理。

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引用次数: 0

Exploring rotational isomerism of fluorescent diarylethenes comprising 2-naphthyl and regioisomeric oxazoyl groups. A combined experimental and computational study 探索包含 2-萘基和草酰基的 Regioisomeric diarylethenes 的荧光旋转异构体。实验与计算相结合的研究

IF 4 2区化学 Q2 CHEMISTRY, PHYSICAL

Journal of Molecular Structure

Pub Date : 2024-11-07 DOI: 10.1016/j.molstruc.2024.140611

Andrzej J. Kałka , Paweł Ręka , Jarosław Grolik , Katarzyna Ostrowska , Andrzej M. Turek

In the paper a phenomenon of rotational (conformational) isomerism within 1,2-diarylethenic compounds (DAE) comprising heteroarene ring of oxazole is explored on the example of the fluorescent naphthyl-vinyl-oxazole framework. In this regard three regioisomers of a n-(2-(naphthalen-2-yl)vinyl)oxazole molecule (nNVOx), differing in the oxazole substitution pattern (n = 2, 4, 5), are synthesized and methodically investigated by means of electronic UV–Vis spectroscopy combined with chemometric methods for spectral data analysis. Design of the experiments and interpretation of their output is additionally supported by quantum-chemical simulations based on the (TD) DFT methodology. As the result, all the studied nNVOx compounds are unveiled to simultaneously occur in form of at least two non-equivalent rotational isomers, varying in the conformation taken by the arene moieties with respect to the central vinyl fragment. The individual rotamers are then demonstrated to exhibit non-identical spectroscopic properties expressed by differences in corresponding absorption and fluorescence profiles, thereby ultimately confirming the impact of rotamerism onto the investigated molecular systems.

本文以荧光萘基乙烯基噁唑框架为例，探讨了包含噁唑杂环的 1,2-二芳基化合物（DAE）中的旋转（构象）异构现象。为此，我们合成了正(2-(萘-2-基)乙烯基)噁唑分子（nNVOx）的三种区域异构体，它们在噁唑取代模式（n = 2、4、5）上各不相同，并通过电子紫外可见光谱结合光谱数据分析的化学计量学方法进行了研究。此外，基于 (TD) DFT 方法的量子化学模拟也为实验设计和结果解释提供了支持。结果揭示出，所有研究的 nNVOx 化合物都同时存在至少两种非等价的旋转异构体，炔基相对于中心乙烯基片段的构象各不相同。这些旋转异构体通过相应的吸收和荧光曲线的差异表现出非相同的光谱特性，从而最终证实了旋转异构体对所研究分子体系的影响。

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引用次数: 0

Long-wavelength red-emitting ClO− fluorescent probe for visualizing inflammation and drug-induced renal injury 用于观察炎症和药物引起的肾损伤的长波长红色发光 ClO- 荧光探针

IF 4 2区化学 Q2 CHEMISTRY, PHYSICAL

Journal of Molecular Structure

Pub Date : 2024-11-07 DOI: 10.1016/j.molstruc.2024.140670

Chuan He, Qi Zhang, Haoqing Ren, Peng Hou, Haijun Wang, Jiaming Wang, Yitong Liu, Song Chen

Hypochlorous acid (ClO⁻), a member of the reactive oxygen species (ROS) family, plays an important role in regulating physiological processes and maintaining homeostasis in the body. However, abnormal ClO⁻ levels in the human body have been associated with a variety of pathological conditions, encompassing inflammation and kidney diseases. In this work, we have developed a novel fluorescent probe, RDNClO, specifically tailored for the sensitive detection of ClO⁻. RDNClO was synthesized through modifying N - (7 - (2 - carboxyphenyl) -3- (dimethylamino) - 5,6 - dihydro - 10H - benzo[c]xanthen - 10 - ylidene) - N - ethylethanaminium (RDNOH) with 1-naphthaloyl chloride moiety. Spectroscopic analyses reveal that RDNClO exhibits outstanding performance characteristics, including high selectivity, a rapid response time of <25 s, and an ultra-low detection limit of 3.7 nM. Additionally, RDNClO has demonstrated exceptional capabilities in detecting ClO⁻ in real water samples and rapidly identifying ClO⁻ in environmental samples, utilizing agarose as a carrier. It effectively monitors both endogenous ClO⁻ levels in HeLa cells and exogenous ClO⁻ levels in HEK293T cells. Furthermore, RDNClO has excelled in tracking fluctuations in ClO⁻ levels, including in Escherichia coli, the mouse model of arthritis induced by k-carrageenan, and a mouse model of cisplatin-induced renal injury. The development of RDNClO not only establishes a robust theoretical foundation for investigating the pathogenic mechanisms of renal injury but also presents a promising tool for advancing research in this critical area.

次氯酸（ClO-）是活性氧（ROS）家族的一员，在调节生理过程和维持体内平衡方面发挥着重要作用。然而，人体内异常的 ClO- 含量与多种病理状况有关，包括炎症和肾脏疾病。在这项工作中，我们开发了一种新型荧光探针 RDNClO，专门用于灵敏检测 ClO-。RDNClO 是通过将 N - (7 - (2 - 羧基苯基) -3- (二甲基氨基) - 5,6 - 二氢 - 10H - 苯并[c]氧杂蒽 - 10 - 亚甲基) - N - 乙基乙铵 (RDNOH) 与 1-萘甲酰氯修饰而合成的。光谱分析显示，RDNClO 具有出色的性能特点，包括高选择性、25 秒的快速响应时间和 3.7 nM 的超低检测限。此外，RDNClO 还利用琼脂糖作为载体，在检测真实水样中的 ClO- 和快速鉴定环境样品中的 ClO- 方面表现出卓越的能力。它能有效监测 HeLa 细胞中的内源性 ClO- 水平和 HEK293T 细胞中的外源性 ClO- 水平。此外，RDNClO 在跟踪 ClO- 水平波动方面也表现出色，包括在大肠杆菌、k-卡拉胶诱导的关节炎小鼠模型和顺铂诱导的肾损伤小鼠模型中。RDNClO 的开发不仅为研究肾损伤的致病机制奠定了坚实的理论基础，而且为推进这一关键领域的研究提供了一个前景广阔的工具。

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引用次数: 0

Facile synthesis, spectroscopic, electronic and non-linear optical properties of 1,2–4 triazole-based derivatives: An experimental and DFT approach 1,2-4 三唑基衍生物的简易合成、光谱、电子和非线性光学特性：实验和 DFT 方法

IF 4 2区化学 Q2 CHEMISTRY, PHYSICAL

Journal of Molecular Structure

Pub Date : 2024-11-07 DOI: 10.1016/j.molstruc.2024.140576

Hammad Ali Khan , Muhammad Irfan , Samreen Gul Khan , Shamsa Bibi , Akbar Ali , Iqra Shafiq , Norah Alhokbany , Muhammad Haroon , Humaira Yasmeen Gondal

In current study, a novel series of 1,2,4-triazole based compounds (7a-7d) was synthesized and their structure confirmation was accomplished through different spectroscopic (UV–Visible, FTIR, NMR and HRMS), elemental analysis and physio-chemical methods. Besides, the electronic properties were investigated through the DFT/TD-DFT approaches at M06/6–311G(d,p) functional. All the synthesized compounds showed simulated band gap in the range of 4.931–5.489 eV with absorption spectrain the range of 295–302 nm calculated experimentally. A significant charge transfer was observed with in molecules as supported by TDM and FMOs investigations. Compound 7a showed good NLO characteristics (β_tot =1.338 × 10⁻²⁹ and <γ>= 7.547 × 10⁻⁵³ esu) among all the synthesized compounds owing to the lowest value of HOMO–LUMO band gap (4.931 eV). Hence it can be utilized as reasonable optoelectronic material for NLO devices.

本研究合成了一系列新型 1,2,4- 三唑类化合物（7a-7d），并通过不同的光谱（紫外-可见光、傅立叶变换红外光谱、核磁共振和 HRMS）、元素分析和物理化学方法确认了这些化合物的结构。此外，还通过 M06/6-311G(d,p)函数的 DFT/TD-DFT 方法研究了它们的电子特性。所有合成化合物的模拟带隙范围为 4.931-5.489 eV，实验计算的吸收光谱范围为 295-302 nm。TDM 和 FMOs 研究证实，分子内存在明显的电荷转移。由于 HOMO-LUMO 带隙值（4.931 eV）最低，化合物 7a 在所有合成化合物中表现出良好的 NLO 特性（βtot =1.338 × 10-29 和 <γ>= 7.547 × 10-53 esu）。因此，它可以作为合理的光电材料用于 NLO 器件。

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引用次数: 0

Catalytic activity study of Nano -Schiff base complexes/Al2O3 system 纳米希夫碱配合物/Al2O3 系统的催化活性研究

IF 4 2区化学 Q2 CHEMISTRY, PHYSICAL

Journal of Molecular Structure

Pub Date : 2024-11-07 DOI: 10.1016/j.molstruc.2024.140669

Shorouk S. Zyn Elabeden, Sahar A. El-Molla, Magdy Shebl, Sameh G. Sanad, Mona A. Naghmash

Cobalt complexes of 4,6-bis[(1E)-N-(2-hydroxyethyl) ethanimidoyl] benzene-1,3-diol) and 4,6-bis [(1E)-N-benzylethanimidoyl] benzene-1,3-diol) ligands were successfully supported on nano alumina. Furthermore, the catalytic performance of these catalysts was evaluated by measuring of hydrogen peroxide decomposition. The catalysts were then examined using high-resolution transmission electron microscopy (HR-TEM), scanning electron microscopy (SEM), N₂ adsorption-desorption analysis, Energy Dispersive X-ray Spectroscopy (EDX), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). It's interesting to note that the loading Co-complexes on Al₂O₃ catalyst resulted in a notable advancement in the catalytic efficiencies compared with single Al₂O₃. However, many parameters influenced the catalytic activity were investigated as reaction temperature, the concentration of Co-complexes. Results denoted that 0.015 Co-complexes / Al₂O₃ have the highest catalytic activity and showed greater stability throughout the H₂O₂ decomposition process and is recyclable several times.

成功地将 4,6-双[(1E)-N-(2-羟乙基)乙脒酰基]苯-1,3-二醇配体和 4,6-双[(1E)-N-苄基乙脒酰基]苯-1,3-二醇配体的钴配合物支撑在纳米氧化铝上。此外，这些催化剂的催化性能还通过测定过氧化氢的分解得到了评估。然后使用高分辨率透射电子显微镜 (HR-TEM)、扫描电子显微镜 (SEM)、N2 吸附-解吸分析、能量色散 X 射线光谱 (EDX)、X 射线衍射 (XRD) 和傅立叶变换红外光谱 (FTIR) 对催化剂进行了检测。值得注意的是，与单一 Al2O3 相比，在 Al2O3 催化剂上负载 Co-络合物显著提高了催化效率。然而，影响催化活性的参数很多，如反应温度、钴络合物的浓度等。结果表明，0.015 Co-络合物/Al2O3 的催化活性最高，在整个 H2O2 分解过程中表现出更高的稳定性，并可多次循环使用。

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引用次数: 0

Synthesis of Co/Ni-MOFs with mixed ligands and their Oxygen Evolution Reaction (OER) performance 具有混合配体的 Co/Ni-MOFs 的合成及其氧进化反应 (OER) 性能

IF 4 2区化学 Q2 CHEMISTRY, PHYSICAL

Journal of Molecular Structure

Pub Date : 2024-11-07 DOI: 10.1016/j.molstruc.2024.140549

Xuejiao Sun , Lei Yang , Dongmei Li , Zhongzhen Tian

Two new transition metal–organic framework (MOF) complexes, Co-MOF (C₂₈H₁₇CoN₆O₉S₂) and Ni-MOF (C₂₈H₆NNi₈O₂S_0.06), were synthesized using a hydrothermal method. Upon characterization and analysis, Co-MOF and Ni-MOF showed similar structures, in which Co²⁺ or Ni²⁺ coordinated with two pyridine-2,6-dicarboxylic acid ligands to form octahedral geometric configurations, which in turn formed one-dimensional layered structure, while Py₂TTz ligands existed between these layers to enlarge the pore size of MOFs. Co-MOF showed superior performance than Ni-MOF in the OER process, with a low overpotential (227 mV) and Tafel slope (51.4 mV dec^‑1) at 10 mA cm^-2 current density. This work provided new insight into designing transition MOFs for electrocatalytic water splitting.

采用水热法合成了两种新的过渡金属有机框架（MOF）配合物 Co-MOF（C28H17CoN6O9S2）和 Ni-MOF （C28H6NNi8O2S0.06）。经表征和分析，Co-MOF 和 Ni-MOF 显示出相似的结构，其中 Co2+ 或 Ni2+ 与两个吡啶-2,6-二羧酸配体配位形成八面体几何构型，进而形成一维层状结构，而 Py2TTz 配体则存在于这些层之间，以扩大 MOF 的孔径。在 10 mA cm-2 电流密度下，Co-MOF 的过电位（227 mV）和 Tafel 斜率（51.4 mV dec-1）均较低，在 OER 过程中表现出比 Ni-MOF 更优越的性能。这项工作为设计用于电催化水分离的过渡 MOF 提供了新的见解。

引用次数: 0

A rapid colorimetric sensor for the detection of mercury in environmental samples employing 2 aminobenzohydrazide schiff base functionalized silver nanoparticles 利用 2 氨基苯甲酰二硫基官能化银纳米粒子检测环境样品中汞的快速比色传感器

IF 4 2区化学 Q2 CHEMISTRY, PHYSICAL

Journal of Molecular Structure

Pub Date : 2024-11-07 DOI: 10.1016/j.molstruc.2024.140587

Imdad Ali , Sarzamin Khan , Carlos A.T. Toloza , Zafar Ali Shah , Zafar Iqbal , Riaz Ullah , Muhammad Raza Shah

Mercury (Hg²⁺) is an extremely toxic and dangerous element for living organisms. Herein, a simple and selective sensor based on the Schiff base of 2-aminobenzohydrazide with triazole thiazole substituted vanillin (EAHT) functionalized silver nanoparticles (EAHT-AgNPs) is proposed for the detection of Hg²⁺ in environmental water samples. The chemical reduction method was employed to synthesize EAHT-AgNPs using sodium borohydride as the reducing agent. The synthesized nanoparticles were initially confirmed by UV-visible and FTIR spectroscopy, followed by analysis with a zeta sizer to determine their average size, surface charge and polydispersity index. The atomic force microscopy (AFM) and scanning electron microscopy (SEM) were employed to determine the size and morphology of EAHT-AgNPs. Additionally, the functionalized particles exhibited stability at varying pH values, salinity concentrations and elevated temperature. The addition of Hg²⁺ altered the yellow color of EAHT-AgNPs to colorless, confirming the complex formation. The analytical response constructed as a decrease in absorbance versus concentration showed linearity (R² = 0. 991) from 0.1 to 100 µM with a limit of detection of 0.04 µM (40 nM) and limit of quantification of 0.085 µM (85 nM). The sensor was successfully applied for the detection of Hg²⁺ ions in tap water. In conclusion, Schiff base of 2-aminobenzohydrozide with triazole thiazole substituted vanillin silver nanoparticle-based chemosensor is highly sensitive and selective for the detection of Hg²⁺ in water samples. The proposed sensor has been applied for mercury detection tap water, future research should explore its applications in more complex samples like industrial wastewater and marine environments. Further, studies may focus on the integrating of the approach into the portable devices such as smartphone for on-site detection of mercury.

汞（Hg2+）是一种对生物体毒性极大的危险元素。本文提出了一种基于 2-aminobenzohydrazide 的席夫碱与三唑噻唑取代香兰素（EAHT）功能化银纳米粒子（EAHT-AgNPs）的简单选择性传感器，用于检测环境水样中的 Hg2+。以硼氢化钠为还原剂，采用化学还原法合成了 EAHT-AgNPs。首先用紫外-可见光光谱和傅立叶变换红外光谱对合成的纳米粒子进行了确认，然后用 zeta 分析仪对其平均粒度、表面电荷和多分散指数进行了分析。原子力显微镜（AFM）和扫描电子显微镜（SEM）用于确定 EAHT-AgNPs 的尺寸和形态。此外，功能化颗粒在不同的 pH 值、盐浓度和高温条件下均表现出稳定性。Hg2+ 的加入使 EAHT-AgNPs 的黄色变为无色，证实了复合物的形成。吸光度的下降与浓度的关系所构建的分析响应显示出 0.1 至 100 µM 的线性关系（R2=0.991），检测限为 0.04 µM（40 nM），定量限为 0.085 µM（85 nM）。该传感器已成功应用于自来水中 Hg2+ 离子的检测。总之，基于 2-aminobenzohydrozide 的希夫碱与三唑噻唑取代香兰素银纳米粒子的化学传感器对检测水样中的 Hg2+ 具有高灵敏度和高选择性。所提出的传感器已应用于自来水中的汞检测，未来的研究应探索其在工业废水和海洋环境等更复杂样品中的应用。此外，研究重点可能是将该方法集成到智能手机等便携式设备中，用于现场检测汞。

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引用次数: 0

Visible light degradation of antibiotics catalyzed by nanoporous carbon/V2O5 nanocomposite: structural, optical and electrochemical properties 纳米多孔碳/V2O5 纳米复合材料催化的抗生素可见光降解：结构、光学和电化学特性

IF 4 2区化学 Q2 CHEMISTRY, PHYSICAL

Journal of Molecular Structure

Pub Date : 2024-11-06 DOI: 10.1016/j.molstruc.2024.140615

M.V. Arularasu , M. Yasmin Begum , Ali Alamri , Adel Al Fatease

In this study, nanoporous carbon (NPC) decorated V₂O₅ (NPC/V₂O₅) nanocomposite synthesized by a hydrothermal technique using biomass-derived NPC nanoflakes towards the application of berberine hydrochloride (BH) dye degradation under visible light irradiation. The prepared samples were characterized by X-ray Diffraction (XRD), Raman spectroscopy, Field Emission Scanning Electron Microscopy (FE-SEM), Transmission Electron Microscopy (TEM), Energy-Dispersive X-ray (EDX), UV–Visible and Photoluminescence (PL) spectroscopy. Charge transfer resistance was measured by electrochemical impedance spectroscopy (EIS) and liner sweep voltammetry (LSV). XRD studies confirm the orthorhombic crystal structure of NPC/V₂O₅ nanocomposite. FE-SEM and TEM analysis validate their particle-like and sheet-like morphology of V₂O₅ and NPC respectively. Further, UV–visible DRS and PL spectra of the green synthesized NPC/V₂O₅ nanocomposite exhibited a low band-gap and reduced recombination rate compared to the pure counterpart which is better light-absorbing ability in the visible light region. Batch experiments represent the incorporation of NPC and V₂O₅ would lead to an increase the photocatalytic performance of NPC/V₂O₅ toward BH dye degradation. During the photocatalytic reaction, the NPC/V₂O₅ nanocomposite degraded rate around 97.7 % against BH dye within 80 min while pure V₂O₅ degraded 92.5 % of BH dye under same visible light irradiation time. Finally, the cyclic stability experiment exhibits the photocatalyst even stable after five consecutive tests.

本研究采用水热技术合成了纳米多孔碳（NPC）装饰的 V2O5（NPC/V2O5）纳米复合材料，并将其用于可见光照射下盐酸小檗碱（BH）染料的降解。制备的样品通过 X 射线衍射 (XRD)、拉曼光谱、场发射扫描电子显微镜 (FE-SEM)、透射电子显微镜 (TEM)、能量色散 X 射线 (EDX)、紫外可见光和光致发光 (PL) 光谱进行表征。电荷转移电阻是通过电化学阻抗谱（EIS）和衬垫扫描伏安法（LSV）测量的。XRD 研究证实了 NPC/V2O5 纳米复合材料的正方晶体结构。FE-SEM 和 TEM 分析分别验证了 V2O5 和 NPC 的颗粒状和片状形态。此外，绿色合成的 NPC/V2O5 纳米复合材料的紫外可见 DRS 和 PL 光谱显示，与纯材料相比，它们具有较低的带隙和较低的重组率，在可见光区域具有更好的光吸收能力。批量实验表明，NPC 和 V2O5 的加入会提高 NPC/V2O5 对 BH 染料降解的光催化性能。在光催化反应过程中，NPC/V2O5 纳米复合材料在 80 分钟内对 BH 染料的降解率约为 97.7%，而在相同的可见光照射时间内，纯 V2O5 对 BH 染料的降解率为 92.5%。最后，循环稳定性实验表明，光催化剂在连续 5 次测试后仍然保持稳定。

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引用次数: 0

Anticancer and acute toxicity studies of cellulose-coated Vanadium oxide nanomaterials 纤维素涂层氧化钒纳米材料的抗癌和急性毒性研究

IF 4 2区化学 Q2 CHEMISTRY, PHYSICAL

Journal of Molecular Structure

Pub Date : 2024-11-06 DOI: 10.1016/j.molstruc.2024.140633

Zartasha Sarwar , Muhammad Khawar Abbas , Naveed Akhtar Shad , Kanwal Akhtar , Ameena Mobeen , Waseem Abbas , Kh. Abd El-Aziz , Muhammad Rizwan Tabassum , Muhammad Zulqarnain , Hafiz T. Ali , Yasir Javed , Sumara Ashraf

In the present research work, a facile hydrothermal method has been used for the preparation of pristine and cellulose-coated Vanadium oxide (V₂O₅) nanoparticles (NPs). The as-synthesized nanostructures were characterized using XRD, SEM, UV–Vis, PL, DLS, Raman, and FTIR spectroscopy. The crystallite size of the bare V₂O₅ NPs calculated using XRD analysis was ∼19 nm, which was reduced to ∼16 nm after cellulose functionalization. TEM micrographs revealed the formation of spherical shape NPs with sizes 21 ± 4.9 nm and 16.5 ± 4.4 nm for V₂O₅ and cellulose – V₂O₅ respectively. Cellulose-coated Vanadium oxide NPs have shown anticancer potential against the liver cancer cell line (HuH-7.0). Cell viability of V₂O₅ displayed the IC₅₀ value of 102.182 μg/mL, compared to the coated Vanadium oxide, which was 49.402 μg/mL. In vivo toxicity studies were conducted using healthy albino rats. Pathological parameters indicate acute toxicity due to cellulose-coated Vanadium oxide NPs. The histopathology of cellulose-V₂O₅ NPs treated livers indicates the swelling in hepatocytes and compressed sinusoidal spaces.

在本研究工作中，采用了一种简便的水热法来制备原始的和纤维素包覆的氧化钒（V2O5）纳米粒子（NPs）。利用 XRD、SEM、UV-Vis、PL、DLS、拉曼和傅立叶变换红外光谱对合成的纳米结构进行了表征。通过 XRD 分析计算出的裸 V2O5 NPs 的晶粒尺寸为 19 纳米，纤维素功能化后晶粒尺寸减小到 16 纳米。TEM 显微照片显示，V2O5 和纤维素 - V2O5 形成的球形 NPs 大小分别为 21 ± 4.9 nm 和 16.5 ± 4.4 nm。纤维素包裹的氧化钒 NPs 对肝癌细胞株（HuH-7.0）具有抗癌潜力。V2O5 的细胞活力 IC50 值为 102.182 μg/mL，而涂覆氧化钒的 IC50 值为 49.402 μg/mL。使用健康的白化大鼠进行了体内毒性研究。病理学参数表明，纤维素包覆的氧化钒 NPs 具有急性毒性。经纤维素-V2O5 NPs 处理的肝脏的组织病理学显示，肝细胞肿胀，肝窦间隙受压。

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引用次数: 0

Targeting metallo-β-lactamase inhibition with Schiff bases of 4-amino-1,2,4-triazole-3-thione: In silico docking, molecular dynamics, and pharmacological assessments 以 4-氨基-1,2,4-三唑-3-硫酮的希夫碱抑制金属-β-内酰胺酶为目标：硅对接、分子动力学和药理学评估

IF 4 2区化学 Q2 CHEMISTRY, PHYSICAL

Journal of Molecular Structure

Pub Date : 2024-11-06 DOI: 10.1016/j.molstruc.2024.140629

Amit C. Mishra , Jagatkumar Upadhyay , Prashant P. Dixit , Kamalkishor Baheti , Shivaji N. Thore

Metallo-β-lactamases are zinc-dependent enzymes that hydrolyze and inactivate a wide range of β-lactam antibiotics, including penicillins, cephalosporins, and carbapenems, making them a significant factor in bacterial resistance. Therefore, developing inhibitors targeting metallo-β-lactamases is crucial for combating antibiotic resistance in Gram-negative bacteria and restoring the effectiveness of these essential antimicrobial agents. This study focuses on the synthesis, in silico docking, molecular dynamics simulations, and biological evaluation of twenty-one Schiff base analogs (6a–u) derived from trans-4-amino-5-(4-(4-chlorophenyl)cyclohexyl)-1,2,4-triazole-3-thione. Molecular docking studies were carried out on the New Delhi metallo-β-lactamase-1 active sites of Klebsiella pneumoniae (PDB: 5N0H) and Escherichia coli (PDB: 6KXI) to evaluate the binding interactions between the thiolate form of ligands and zinc ions. Docking analysis reveals that the synthesized analogs are stably positioned in the NDM-1 active site, aligning closely with zinc ions. The zinc ions in the active binding site coordinate with the nitrogen atoms of the triazole ring and the thiolate anion. Molecular Dynamics Simulations confirmed the stability of the protein-ligand complexes, demonstrating that the ligands maintained optimal positioning within the active site with minimal fluctuations in surrounding residues. The in vitro antibacterial activity of these analogs was evaluated at concentrations of 4 mg/L and 8 mg/L in combination with meropenem against various carbapenem-resistant Gram-negative isolates expressing NDM-1, Class A (SHV, TEM), or Class C (CMY) β-lactamases. The results indicated modest potentiation of meropenem's antibacterial activity, with a 2–3 fold increase in efficacy when used alongside the Schiff base analogs. Notably, two analogs emerged as significant hits in this study.

金属-β-内酰胺酶是一种锌依赖性酶，可水解和灭活多种 β-内酰胺类抗生素，包括青霉素类、头孢菌素类和碳青霉烯类，使其成为细菌耐药性的一个重要因素。因此，开发针对金属-β-内酰胺酶的抑制剂对于对抗革兰氏阴性细菌的抗生素耐药性以及恢复这些重要抗菌药物的有效性至关重要。本研究的重点是 21 个由反式-4-氨基-5-(4-(4-氯苯基)环己基)-1,2,4-三唑-3-硫酮衍生的希夫碱类似物（6a-u）的合成、硅对接、分子动力学模拟和生物学评价。对肺炎克雷伯氏菌（PDB：5N0H）和大肠埃希氏菌（PDB：6KXI）的新德里金属-β-内酰胺酶-1 活性位点进行了分子对接研究，以评估配体的硫酸盐形式与锌离子之间的结合相互作用。对接分析表明，合成的类似物稳定地位于 NDM-1 活性位点，与锌离子紧密结合。活性结合位点中的锌离子与三唑环的氮原子和硫代阴离子配位。分子动力学模拟证实了蛋白质-配体复合物的稳定性，表明配体在活性位点内保持最佳定位，周围残基的波动极小。针对表达 NDM-1、A 类（SHV、TEM）或 C 类（CMY）β-内酰胺酶的各种耐碳青霉烯类革兰氏阴性分离菌，评估了这些类似物与美罗培南联用时的体外抗菌活性，浓度分别为 4 mg/L 和 8 mg/L。研究结果表明，美罗培南的抗菌活性有适度的增效作用，与希夫碱类似物同时使用时，药效可提高 2-3 倍。值得注意的是，有两种类似物在这项研究中出现了重大突破。

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