Electrochemistry

电化学
  • 文章类型: Journal Article
    聚合物改性已被确立为具有成本效益的,简单,用于克服硼掺杂金刚石(BDD)电极的一些固有缺点的原位方法,它的应用已经扩展到可靠,低成本的环境监测解决方案。本综述的重点是用半导电聚合物作为氧化还原介体来修饰BDD电极。本文报道了3-甲基噻吩修饰的硼掺杂金刚石(BDD/P3MT)传感器的开发,用于电化学测定茶叶样品中的总酚类化合物(TPCs),使用没食子酸(GA)作为标记。GA是一种具有多种生物活性的重要多酚,使其量化至关重要。因此,一个简单的,快,使用电分析方波伏安法(SWV)技术制造了灵敏的GA传感器。传感器采用半导电聚合物,3-甲基噻吩,作为氧化还原介体,提高BDD的灵敏度和选择性。电化学合成用于聚合物沉积,允许更高的纯度和避免溶解度问题。BDD/P3MT传感器具有良好的电化学性能,包括快速的电荷转移和大的电化学面积,能够进行GA检测,检测限为11mg/L。传感器的响应与Folin-Ciocalteu方法测得的TPC相关。在最佳条件下,方波伏安法(SWV)在3-71mg/L的宽线性范围内,峰电流与GA浓度之间具有良好的线性关系。BDD/P3MT传感器精确测量绿茶中的TPC,路易波斯茶,和红茶样品,绿茶表现出最高的TPC水平。结果表明,该修饰的BDD电极具有快速准确检测茶叶中酚类化合物的潜力,对质量控制和抗氧化活性评估有影响。过去十年的大量出版物已经将BDD电极确立为用于定量多酚的强大的BDD传感器。水果,蔬菜,坚果,植物源性饮料,如茶和酒,传统的东方疗法和各种草药营养补充剂含有酚类化学物质。受污染食物摄入的安全问题是全球重大的健康问题,因为食品安全之间存在着至关重要的联系,营养,和粮食安全。众所周知,食用绿茶多酚可促进积极的健康效果。尽管它们有潜在的好处,由于对潜在负面影响的担忧,大量食用这些多酚引发了争论。
    Polymer modification has been established as a cost-effective, simple, in situ method for overcoming some of the inherent disadvantages of boron-doped diamond (BDD) electrodes, and its application has been extended to reliable, low-cost environmental monitoring solutions. The present review focuses on modifying BDD electrodes with semi-conductive polymers acting as redox mediators. This article reports on the development of a 3-methyl thiophene-modified boron-doped diamond (BDD/P3MT) sensor for the electrochemical determination of total phenolic compounds (TPCs) in tea samples, using gallic acid (GA) as a marker. GA is a significant polyphenol with various biological activities, making its quantification crucial. Thus, a simple, fast, and sensitive GA sensor was fabricated using the electroanalytical square wave voltammetry (SWV) technique. The sensor utilizes a semi-conductive polymer, 3-methyl thiophene, as a redox mediator to enhance BDD\'s sensitivity and selectivity. Electrochemical synthesis was used for polymer deposition, allowing for greater purity and avoiding solubility problems. The BDD/P3MT sensor exhibits good electrochemical properties, including rapid charge transfer and a large electrochemical area, enabling GA detection with a limit of detection of 11 mg/L. The sensor\'s response was correlated with TPCs measured by the Folin-Ciocalteu method. Square wave voltammetry (SWV) showed a good linear relationship between peak currents and GA concentrations in a wide linear range of 3-71 mg/L under optimal conditions. The BDD/P3MT sensor accurately measured TPCs in green tea, rooibos tea, and black tea samples, with green tea exhibiting the highest TPC levels. The results demonstrate the potential of the modified BDD electrode for the rapid and accurate detection of phenolic compounds in tea, with implications for quality control and antioxidant activity assessments. The prolific publications of the past decade have established BDD electrodes as robust BDD sensors for quantifying polyphenols. Fruits, vegetables, nuts, plant-derived beverages such as tea and wine, traditional Eastern remedies and various herbal nutritional supplements contain phenolic chemicals. The safety concerns of contaminated food intake are significant health concerns worldwide, as there exists a critical nexus between food safety, nutrition, and food security. It has been well established that green tea polyphenol consumption promotes positive health effects. Despite their potential benefits, consuming high amounts of these polyphenols has sparked debate due to concerns over potential negative consequences.
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  • 文章类型: Journal Article
    了解反应中中间体/活性物质的性质是化学中的主要挑战。这是因为观众物种通常主导实验得出的数据,因此活跃相位贡献被掩盖。瞬态方法提供了一种绕过这一困难的手段。特别是,具有相敏检测的调制激励(ME-PSD)提供了区分观察者和反应物质的机制。在这里,调制激发(ME)时间分辨(能量色散)X射线吸收光谱,通过相敏检测(PSD)分析,已应用于液相过程的研究;在这种情况下,经典的亚铁氰化物/铁氰化物氧化还原对。电势的周期性切换(阳极/阴极)使得能够使用ME方法。在包含约30pmolFe(II)/Fe(III)的X射线束探针体积内,检测到低至电活性物质总数2%的部分的结构变化。
    Understanding nature of intermediates/active species in reactions is a major challenge in chemistry. This is because spectator species typically dominate the experimentally derived data and consequently active phase contributions are masked. Transient methods offer a means to bypass this difficulty. In particular, modulation excitation with phase-sensitive detection (ME-PSD) provides a mechanism to distinguish between spectator and reacting species. Herein, modulation excitation (ME) time-resolved (energy dispersive) X-ray absorption spectroscopy, assisted by phase sensitive detection (PSD) analysis, has been applied to the study of a liquid phase process; in this case the classic ferrocyanide/ferricyanide redox couple. Periodic switches of the electrical potential (anodic/cathodic) enabled the use of the ME approach. Structural changes at fractions as low as 2% of the total number of electroactive species were detected within the X-ray beam probe volume containing ~30 pmol of Fe(II)/Fe(III).
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  • 文章类型: Journal Article
    研究老化机制与充电状态(SOC)之间的相关性可以优化锂离子电池(LIB)的循环条件并延长其寿命。通常采用某个SOC范围之间的长期循环来研究这种相关性。然而,这种方法需要很长的时间,从几个月到几年,显著延长研究时间。通过该方法获得的老化机制是各种SOC水平耦合的结果;特定SOC水平下的老化机制不是精确解耦和可分析的。提出的零和脉冲方法,使用SOC幅度变化较小的对称脉冲,可以探索LIB在特定SOC水平下的老化机制,并将时间减少到不到一周,这大大加快了研究进程。在30%的老化机制,50%,70%,90%的SOC水平,验证了该方法的准确性和时效性。
    Investigating the correlation between aging mechanisms and state of charge (SOC) can optimize cycling conditions and prolong the life cycle of lithium-ion batteries (LIBs). A long-term cycle between a certain SOC range is usually employed to study this correlation. However, this method necessitates a lengthy period, running from months to years, prolonging the research duration significantly. The aging mechanisms obtained through this method are a result of the coupling of various SOC levels; the aging mechanisms at a specific SOC level are not accurately decoupled and analyzable. The proposed Zero-sum pulse method, using symmetrical pulses with small SOC amplitude variations on SOC, can explore aging mechanisms of LIBs at a specific SOC level and reduce the time to less than a week, which significantly expedite the research process. The aging mechanisms at 30%, 50%, 70%, and 90% SOC levels are explored to verify the accuracy and timeliness of this method.
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  • 文章类型: Journal Article
    胃肠道寄生虫是反刍动物的主要健康和福利问题。合成化学驱虫药已导致胃肠道强体产生耐药性,诱导寻找替代品来控制影响反刍动物的感染。这项工作的目的是评估植物提取物对hemonchuscontortusRudolphi的驱虫潜力。瓜德罗普岛生物多样性的三种植物,苦瓜,番木瓜和马尾藻属。,基于它们的高多酚含量和天然丰度选择。探索了植物的植物化学,对寄生虫H.contortus进行了生物测定,并通过创新的电化学筛选方法提出了关于作用方式的几个假设。
    Gastrointestinal parasitism is a major health and welfare problem in ruminants. Synthetic chemical anthelmintic drugs have led to the emergence of resistance in gastrointestinal strongyles, inducing the search for alternatives to control the infections that affect ruminants. The objective of this work was to evaluate the anthelmintic potential of plant extracts against Haemonchus contortus Rudolphi. Three plants of the Guadeloupean biodiversity, Momordica charantia L., Carica papaya L. and Sargassum spp., were selected based on their high polyphenolic content and natural abundance. The phytochemistry of plants was explored, a biological assay against the parasite H. contortus was carried out, and several hypotheses about the way of action were proposed by an innovative electrochemical screening method.
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  • 文章类型: Journal Article
    由于越来越多的人口更加关注个人健康,由于生活水平的提高,迫切需要改进个人医疗保健设备。这些设备目前需要费力,耗时,以及严重依赖繁琐设备的复杂程序,在样本采集等侵入性方法期间给患者带来不适和疼痛,采血,和其他传统的台式技术。解决方案在于开发新的柔性温度传感器,湿度,湿度应变,压力,以及汗液检测和监测能力,模仿皮肤的一些感官能力。在这次审查中,关于柔性传感器的主题的全面介绍,选择的材料,制造工艺,趋势已经形成。结论是碳基复合材料,以及石墨烯及其衍生物,由于其机电稳定性而引起了极大的兴趣,非凡的导电性,高比表面积,品种,成本相对较低。
    Due to an ever-increasing amount of the population focusing more on their personal health, thanks to rising living standards, there is a pressing need to improve personal healthcare devices. These devices presently require laborious, time-consuming, and convoluted procedures that heavily rely on cumbersome equipment, causing discomfort and pain for the patients during invasive methods such as sample-gathering, blood sampling, and other traditional benchtop techniques. The solution lies in the development of new flexible sensors with temperature, humidity, strain, pressure, and sweat detection and monitoring capabilities, mimicking some of the sensory capabilities of the skin. In this review, a comprehensive presentation of the themes regarding flexible sensors, chosen materials, manufacturing processes, and trends was made. It was concluded that carbon-based composite materials, along with graphene and its derivates, have garnered significant interest due to their electromechanical stability, extraordinary electrical conductivity, high specific surface area, variety, and relatively low cost.
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  • 文章类型: Journal Article
    在这项研究中,合成了几种四苯基卟啉衍生物,每个具有独特的内消旋取代基,包括苯基,甲氧基苯基,丁氧基苯基,辛氧基苯基,和十氧基苯基.此外,制备了它们相应的铜配合物并进行了彻底的表征。通过CHN元素分析确定所有化合物的结构,质谱,和FT-IR光谱。随着烷基长链中碳原子数的增加,观察到电子吸收带中的轻微红移,这归因于烷基的电子影响。DFT分析表明,电子密度主要位于无金属卟啉和铜(II)卟啉配合物的卟啉环上,在内消旋芳基长链取代基的p轨道上具有相对低的电子密度。铜(II)离子络合物的EPR光谱揭示了信号,表明它们的顺磁性。此外,铜(II)四苯基卟啉(CuTPP)配合物在+0.97V和+1.35V处显示两个可逆氧化峰,而其他衍生物表现出较低的氧化电位。使用MTT测定法评估这些化合物对MCF-7细胞系的细胞毒性,揭示在所有情况下的细胞毒性作用。其中,铜(II)四(4-甲氧基苯基)卟啉(CuTOMPP)显示出最高的电势,IC50值为32.07μg/mL。
    In this study, several derivatives of tetraphenylporphyrin were synthesized, each with unique meso-substituent groups including phenyl, methoxyphenyl, butyloxyphenyl, octyloxyphenyl, and dectyloxyphenyl. Additionally, their corresponding copper complexes were prepared and thoroughly characterized. The structural confirmation of all compounds was established through CHN elemental analysis, mass spectrometry, and FT-IR spectroscopy. As the number of carbon atoms in the alkyl long-chain increased, a slight red shift in the electronic absorption band was observed, which was attributed to the electronic influence of the alkyl group. DFT analysis indicated that electron density predominantly localized on the porphyrin ring of both the metal free porphyrins and copper (II) porphyrin complexes, with relatively low electron density in the p orbital of the meso-aryl long-chain substituent group. EPR spectroscopy of the Copper (II) ion complexes revealed signals, indicating their paramagnetic properties. Additionally, the Copper (II) tetraphenylporphyrin (CuTPP) complexes displayed two reversible oxidation peaks at +0.97 V and +1.35 V, whereas other derivatives exhibited lower oxidation potentials. The cytotoxicity of these compounds against MCF-7 cell lines was assessed using MTT assay, revealing cytotoxic effects in all cases. Among them, Copper (II) tetrakis (4-methyloxyphenyl)porphyrin (CuTOMPP) demonstrated the highest potential, with an IC50 value of 32.07 μg/mL.
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  • 文章类型: Journal Article
    为了应对快速的迫切要求,精确,以及在重症监护病房(ICU)中对通气患者进行具有成本效益的检测,以及需要克服传统检测方法的局限性,研究人员已经把注意力转向推进新技术。其中,生物传感器已成为实现准确和早期诊断的可靠平台。在这项研究中,我们探讨了在呼吸机相关性肺炎(VAP)和通气患者的下呼吸道感染中使用Pypalyin分析早期检测病原体的可能性.为了实现这一点,我们开发了一种利用氧化石墨烯-氧化铜掺杂MgO(GO-Cu-Mgo)(GCM)催化剂的电化学传感器,用于检测氰化素。氰化素是吩嗪组中由铜绿假单胞菌菌株产生的一种毒力因子,导致肺炎等感染,尿路感染,囊性纤维化.我们还研究了使用DNA适体检测作为绿脓杆菌的生物标志物的花青素,VAP的常见致病因子。这项研究的结果表明,使用GCM催化剂对Pymicroin进行电化学检测显示出各种应用的潜力,包括临床诊断和药物发现。
    In response to the urgent requirement for rapid, precise, and cost-effective detection in intensive care units (ICUs) for ventilated patients, as well as the need to overcome the limitations of traditional detection methods, researchers have turned their attention towards advancing novel technologies. Among these, biosensors have emerged as a reliable platform for achieving accurate and early diagnoses. In this study, we explore the possibility of using Pyocyanin analysis for early detection of pathogens in ventilator-associated pneumonia (VAP) and lower respiratory tract infections in ventilated patients. To achieve this, we developed an electrochemical sensor utilizing a graphene oxide-copper oxide-doped MgO (GO - Cu - Mgo) (GCM) catalyst for Pyocyanin detection. Pyocyanin is a virulence factor in the phenazine group that is produced by Pseudomonas aeruginosa strains, leading to infections such as pneumonia, urinary tract infections, and cystic fibrosis. We additionally investigated the use of DNA aptamers for detecting Pyocyanin as a biomarker of Pseudomonas aeruginosa, a common causative agent of VAP. The results of this study indicated that electrochemical detection of Pyocyanin using a GCM catalyst shows promising potential for various applications, including clinical diagnostics and drug discovery.
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  • 文章类型: Journal Article
    在本文中,基于环丁砜的氟化化合物,环戊酮,并对γ-丁内酯进行了计算研究,专注于它们在电化学器件和酸碱相关研究中的适用性。具有(1)高极性溶剂的候选物,(2)良好的电化学稳定性,(3)寻找低碱度。其中一些化合物是首次研究。电化学稳定性,介电常数,沸点,基础,和亲油性使用DFT和COSMO-RS方法进行了经验校正。研究了氟化对这些性能以及键参数的影响。概述了所提出的化合物的可能合成路线。一些分子显示出对溶剂有利的估计性质的组合,尽管所研究的化合物中没有一个有望超过乙腈和碳酸亚丙酯的电化学稳定性窗口的宽度。
    In this paper, fluorinated compounds based on sulfolane, cyclopentanone, and gamma-butyrolactone are studied computationally, focusing on their applicability in electrochemical devices and acid-base-related studies. Candidates for solvents with (1) high polarity, (2) good electrochemical stability, and (3) low basicity were searched for. Some of the compounds are studied here for the first time. Electrochemical stabilities, dielectric constants, boiling points, basicities, and lipophilicities were estimated using DFT and COSMO-RS methods with empirical corrections. The effect of fluorination on these properties as well as the bond parameters was studied. The possible synthesis routes of the proposed compounds are outlined. Some molecules display a combination of estimated properties favorable for a solvent, although none of the studied compounds are expected to surpass acetonitrile and propylene carbonate by the width of the electrochemical stability window.
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  • 文章类型: Journal Article
    在这项研究中,我们使用差分脉冲伏安法(DPV)研究了双链脱氧核糖核酸(dsDNA)和姜黄素(CU)之间的结合模式,紫外-可见光谱,和分子对接。通过使用这些技术,我们预测了dsDNA和CU的小沟区域内的结合。重要的是,我们采用了电化学,特别是循环伏安法(CV),探讨温度对dsDNA与CU结合的影响。据我们所知,这是第一个利用电化学方法研究这种结合相互作用的温度依赖性行为的研究。我们的发现揭示了结合常数的温度依赖性变化:25°C时为2.42×103M-1,在30°C时4.26×103M-1,在35°C时5.44×103M-1,在40°C时6.29×103M-1,和7.52×103M-1在45℃。值得注意的是,结合常数随着温度的升高而表现出增加的趋势,表明结合相互作用的温度依赖性增强。
    In this study, we investigated the binding mode between double-stranded deoxyribonucleic acid (dsDNA) and curcumin (CU) using differential pulse voltammetry (DPV), UV-Vis spectroscopy, and molecular docking. By employing these techniques, we predicted the binding within the minor groove region of dsDNA and CU. Significantly, we employed electrochemistry, specifically cyclic voltammetry (CV), to explore the temperature effect on the dsDNA and CU binding. To the best of our knowledge, this is the first study to utilize electrochemical methods for investigating the temperature-dependent behavior of this binding interaction. Our findings revealed temperature-dependent variations in the binding constants: 2.42 × 103 M-1 at 25 °C, 4.26 × 103 M-1 at 30 °C, 5.44 × 103 M-1 at 35 °C, 6.29 × 103 M-1 at 40 °C, and 7.52 × 103 M-1 at 45 °C. Notably, the binding constant exhibited an increasing trend with elevated temperatures, indicating a temperature-dependent enhancement of the binding interaction.
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  • 文章类型: Journal Article
    中药质量是保证其临床应用安全有效的前提。在这项研究中,基于多种检测技术,创新构建了完整的中医四维指纹质量控制系统,并对双黄连口服液进行质量评价。电化学指纹法(ECFP)作为一种新兴的无需预处理的方法,为SHL样品提供了丰富且可量化的信息。通过B-Z振荡系统开发了SHL的第一个定量ECFP。对8个特征参数进行了分析,发现振荡寿命与样品体积呈良好的线性关系,由此添加的样品体积(VL)的计算值显示样品之间的不同波动。更重要的是,高效液相色谱五波长融合指纹图谱(HPLC-FWFP),GC指纹(GC-FP),建立了紫外量子指纹图谱(UV-QFP)。同时,HPLC-FWFP峰的纯度通过双波长吸收系数比光谱(DWAR)验证。成功提出了等加权比定量指纹法(EWRQFM),以提取所有潜在特征,用于样品的整体质量评估。最后,提出了综合评估策略,即变异系数加权算法(VCWA)。HPLC-FWFP的定性和定量评价结果,GC-FP,电化学量子指纹(EC-QFP),通过该方法整合UV-QFP。建立的评价体系也是控制其他中药制剂质量的适宜策略。
    The quality of traditional Chinese medicine (TCM) is the premise to ensure its safety and effectiveness in clinical application. In this study, a complete quality control system for four-dimensional fingerprinting of TCM was innovatively constructed based on multiple detection techniques, and the quality of Shuanghuanglian oral liquid (SHL) was evaluated. Electrochemical fingerprinting (ECFP) as an emerging method without pretreatment provides rich and quantifiable information for SHL samples. The first quantitative ECFP of SHL was developed by the B-Z oscillation system. Eight characteristic parameters were analyzed and a good linear relationship was found between the oscillation lifetime and sample volume, by which the calculated values of the added sample volume (VL) showed different fluctuations between samples. What is more, high-performance liquid chromatography five-wavelength fusion fingerprint (HPLC-FWFP), GC fingerprint (GC-FP), and UV quantum fingerprint (UV-QFP) was established. Meanwhile, the purity of the peaks of the HPLC-FWFP was verified by the dual-wavelength absorption coefficient ratio spectrum (DWAR). Equal weighted ratio quantitative fingerprinting method (EWRQFM) was successfully proposed to extract all potential features for the overall quality assessment of the samples. Finally, a comprehensive evaluation strategy was proposed, namely the variation coefficient weighting algorithm (VCWA). The results of qualitative and quantitative evaluation of HPLC-FWFP, GC-FP, electrochemical quantum fingerprints (EC-QFP), and UV-QFP were integrated by this method. The established evaluation system is also a suitable strategy to control the quality of other TCM preparations.
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