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Dopamine, ascorbic acid and uric acid determination at a poly （Vinyl alcohol） covalently modified glassy carbon electrode

河南省化学会2016年学术年会

作者： Rui Liu Ran Yang Chaojie Qu Haichen Mao Jianjun Li Lingbo Qu The College of Chemistry and Molecular Engineering Zhengzhou University

Highly photoluminescent glycine(GLY) functionalized grapheme quantum dots(GQDs)(GLY-GQDs) were synthesized by a simple and green pyrolysis method employing ethylene glycol as carbon source, GLY as functional molecule. The as-synthesized GLY-GQDs exhibited excellent water solubility with a fluorescence quantum yield of 21.7%. The fluorescence of GLY-GQDs was intensively quenched by Ce via forming non luminescent complexes of GLY-GQDs-Ce. When ascorbic acid(AA) was in presence, Ce was reduced to Ce and the fluorescence of GLY-GQDs regained. In the light of this theory, a simple AA sensor was fabricated without complicated, costly and time-consuming operations. Under the optimal conditions, the fluorescence recovery ratio and the concentration of AA has a linear relationship in the range of 0.03-17.0 μM and with a detection limit of 25 nM which was one order higher sensitive than the reported methods. Furthermore, this established sensor system also shows a high selectivity toward AA over a wide range of common biological molecules such as uric acid, dopamine and glutathione and so on. The proposed method was successfully applied for the AA detection in serum samples. All these suggested the potential of this GLY-GQDs based sensor in the clinical analysis.

关键词： Glycine functional grapheme quantum dots Cerium(Ⅳ) ascorbic acid Serum samples

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Dopamine, ascorbic acid and uric acid determination at a pol...

ascorbic acid Promotes Arsenic-induced Cytotoxicity in Human Hepatocarcinoma Cells and Their Underlying Mechanisms

中国化学会第十三届有机分析与生物分析学术会议

作者： LIN Xiang-qin, LI Yong-xin (University of Science and Technology of China, Anhui 230026)

＜正＞Dopamine （DA） , ascorbic acid （AA） and uric acid （UA） are important substances in biological fluids especially in mammalian brains. Determining these compounds sensitively and selectively by using elecrochemi-cal methods is still much attractive. Due to the time and space recognition ability of the electrochemical technique, including film or chemically modified electrodes and enzyme immobilized electrodes, have been used for

关键词： Poly (vinyl alcohol) Glassy carbon electrode Dopamine ascorbic acid Uric acid

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Journal of Nanjing Medical University 2004年第6期8卷 297-300页

作者：吴辉文吴向阳陈锡慰南京医科大学形态学实验室南京医科大学附属南京第一医院普外科

Objective: To study synergistic effect with ascorbic acid(AA) on arsenic trioxide inducing human Hepatocarcinoma cell apoptosis, and provide theoretical basis for promoting human Hepatocarcinoma cell apoptosis induced by arsenic trioxide(AT). Methods: Human Hepatocarcinoma cell line BEL-7402 being cultured in vitro, the effect of AT and (or) AA on its growth inhibition and its two intracellular signal molecules was evaluated separately using MTT and Western blot. Results: AT at a few μmol/L concentration could suppress abnormal proliferation of human hepatocarcinoma cells, and initiate their apoptosis by activation of caspase-3, and activate extracellular-signal regulated kinases (ERKs), which were dependent on the dosage of AT conspicuously. The effect of AA on BEL-7402 was not significant; However, AA could effectively enhance AT-induced hepatocarcinoma cell apoptosis and lesion severity through activation of caspase-3 but not ERKs. Conclusion: Caspase-3 and ERKs proteins could involve in arsenic-induced hepatocarcinoma cell apoptosis and differentiation respectively as intracellular signaling molecules; The effect between AT and AA on hepatocarcinoma is synergistic, which further inhibits cell growth and induces apoptosis in human hepatocarcinoma cells through activation of caspase-3 but not ERKs.

关键词： hepatocarcinoma arsenic trioxide ascorbic acid apoptosis caspase-3 extracellular-signal regulated kinases

Responses of two cultivars of Trifolium repens L. to ethylene diurea in relation to ambient ozone

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Journal of Environmental Sciences 2010年第7期22卷 1096-1103页

作者： Shalini Singh Dalbir Kaur S.B.Agrawal M.Agrawal Laboratory of Air Pollution and Global Climate Change Department of BotanyBanaras Hindu University

Three ethylene diurea （EDU） concentrations （0, 150 and 300 mg/L） were used to evaluate the negative impact of ozone （O3） on two cultivars of Trifoliurn repens L. cv. Vardan and Bundel grown under natural field conditions in a suburban area of Varanasi, India. Mean O3 concentrations varied from 30.3 to 46.6 μg/L during the experimental period. Higher photosynthetic pigments and ascorhic acid concentrations were noticed in both EDU-treated cultivars over non-EDU-treated ones, but a reverse trend was found for lipid peroxidation. Growth parameters and biomass also showed increments under EDU treatment of both cultivars. The ratio of variable fluorescence to maximum fluorescence increased significantly in Vardan but not in Bundel upon EDU treatment. Results revealed that EDU concentration of 300 mg/L was more effective to combat the oxidative stress as well as protecting plants from O3 injury symptoms. The test cultivar Vardan is relatively sensitive to O3, thereby can be used as a bioindicator of O3 pollution in areas having higher O3 concentrations. Results also indicated that Bundel has more efficient antioxidant defense system than Vardan and hence was more tolerant to O3 stress.

关键词： Trifolium repens ozone oxidative stress ascorbic acid photosynthetic pigments

Coaxial fiber organic electrochemical transistor with high transconductance

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Nano Research 2023年第9期16卷 11885-11892页

作者： Yuan Fang Jianyou Feng Xiang Shi Yiqing Yang Jiajia Wang Xiao Sun Wenjun Li Xuemei Sun Huisheng Peng State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular Scienceand Laboratory of Advanced MaterialsFudan UniversityShanghai 200438China

Fiber organic electrochemical transistors(OECTs)have received extensive attention in wearable and implantable biosensors because of their high flexibility and low working ***,the transconductance of fiber OECTs is much lower compared with the planar counterparts,leading to low ***,we developed fiber OECTs in a coaxial configuration with microscale channel length to achieve the highest transconductance of 135 mS,which is one to two orders of magnitude higher than that of the state-of-the-art fiber *** fiber OECT based sensors showed high sensitivities of 12.78,20.53 and 3.78 mA/decade to ascorbic acid,hydrogen peroxide and glucose,*** fiber OECTs were woven into a fabric to monitor the glucose in sweat during exercise and implanted in mouse brain to detect ascorbic *** coaxial architectural design offers an effective way to promote the performance of fiber OECTs and realize highly sensitive detection of biochemicals.

关键词： organic electrochemical transistor fiber coaxial structure ascorbic acid hydrogen peroxide glucose

Surface-targeted functionalization of nickel-rich cathodes through synergistic slurry additive approach with multi-level impact using minimal quantity

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Nano Research 2024年第1期17卷 333-343页

作者： Jing Zhang Jiapei Li Longhao Cao Wenhua Cheng Ziyin Guo Xiuxia Zuo Chao Wang Ya-Jun Cheng Yonggao Xia Yudai Huang State Key Laboratory of Chemistry and Utilization of Carbon Based Energy Resources College of ChemistryXinjiang UniversityUrumqi 830017China Ningbo Institute of Materials Technology&Engineering Chinese Academy of SciencesNingbo 315201China School of Materials Science and Engineering Tongji UniversityShanghai 200240China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

LiNi0.8Co0.1Mn0.1O_(2)(NCM811),a Ni-rich layered oxide,is a promising cathode material for high-energy density lithium-ion batteries(LIBs).However,its structural instability,caused by adverse phase transitions and continuous oxygen release,as well as deteriorated interfacial stability due to excessive electrolyte oxidative decomposition,limits its widespread *** address these issues,a new concept is proposed that surface targeted precise functionalization(STPF)of the NCM811 cathode using a synergistic slurry additive(SSA)*** approach involves coating the NCM811 particle surface with 3-aminopropyl dimethoxy methyl silane(3-ADMS),followed by the precise deposition of ascorbic acid via an acid-base *** slurry additives induce the formation of an ultra-thin spinel surface layer and a stable cathode–electrolyte interface(CEI),which enhances the electrochemical kinetics and inhibits crack *** STPF strategy implemented by the SSA approach significantly improves the cyclic stability and rate performance of the NCM811 cathode in both half-cell and full-cell *** work establishes a promising strategy to enhance the structural stability and electrochemical performance of nickel-rich cathodes and provides a feasible route to promote practical applications of high-energy density lithium-ion battery technology.

关键词： nickel-rich cathode slurry additive lithium-ion battery cathode–electrolyte interface ascorbic acid phase transition

Effect of Dietary Administration of Lathyrus sativus Pulse on Intestinal Biochemical Parameters in Normal and Scorbutic Guinea Pigs

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Biomedical and Environmental Sciences 2002年第4期15卷 315-322页

作者： ARCHANAAMBA MANOJKUMAR 等 FoodToxicologyLaboratory BiomembraneToxicologyLaboratoryIndustialToxicologyReserachCenter M.G.MargP.B.No.80.Lucknw－226001India

Objective In order to investigate that ascorbic acid deficiency is responcible for lathyrus toxicity, the effect of dietary feeding of lathyrus pulse in normal and scorbutic guinea pigs for 3 months, on intestinal biochemical parameters was undertaken. Methods The intestinal brush border membrane (BBM) marker and xenobiotic metabolising enzymes (XME) were assayed. Results Exposure to 80% lathyrus alone and in scorbutic conditions showed significant inhibition of alkaline phosphatase (28%-30%), sucrase (19%) and γ-glutamyl transpeptidase (GGT) (15%-27%) enzymes, while Ca2+-Mg2+-ATPase was significantly inhibited (38%) in scorbutic plus lathyrus treated group. The phase I XME (AHH) remained unchanged while the phase II enzyme glutathione-S-tranferase (GST) was significantly decreased (20%-22%) in lathyrus and scorbutic plus lathyrus treated groups. Quinone reductase (QR) activity was found to be significantly decreased in lathyrus exposed group (20%). The intestinal biomarker contents including hexose (25%-34%) and phospholipids (20%-40%) were significantly reduced in lathyrus and scorbutic plus lathyrus exposed animals, while sialic acid showed a significant decrease (28%) in scorbutic plus lathyrus treated group. However, cholesterol levels were signifcantly enhanced (15%-28%) in lathyrus and scorbutic plus lathyrus treated animals. Conclusion The results indicate that oral feeding of lathyrus pulse to guinea pigs can alter BBM parameters as well as XME, which may result in the intestinal toxicity. Further, ascorbic acid deficiency could be one of the pre-disposing factors of lathyrus toxicity.

关键词： ascorbic acid BBM Lathyrus sativus Small intestine XME

Excessive Copper Induces the Production of Reactive Oxygen Species,which is Mediated by Phospholipase D, Nicotinamide Adenine Dinucleotide Phosphate Oxidase and Antioxidant Systems

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Journal of Integrative Plant Biology 2008年第2期50卷 157-167页

作者： Zhong-Lian Yu Jin-Guang Zhang Xue-Chen Wang Jia Chen State Key Laboratory of Plant Physiology and Biochemistry College of Biological Sciences China Agricultural University Beijing 100094 China

Tobacco BY-2 suspension cells were used to study the chemical damage and its associated mechanisms caused by Cu^2＋. Treatment with 100 μmol/L Cu^2＋ generated a large amount of HzOz and thiobarbituric acid-reactive substances （TBARS） in cells. Using phospholipase D （PLD） specific inhibitor （1-butanol） or phosphatidic acid （PA）, we demonstrated that PLD plays an important role in the generation of H2O2 and TBARS. Semi-quantitative reverse-transcriptase polymerase chain reaction and enzyme activity assays with wild type and nicotinamide adenine dinucleotide phosphate （NADPH） oxidaseoverexpressing BY-2 cells revealed that PLD and PA are the key factors leading to NADPH oxidase activation, which is responsible for H2O2 and TBARS production induced by Cu^2＋. Moreover, the content of ascorbic acid （AsA）, an effective antioxidant, was sharply reduced in BY-2 cells exposed to excessive Cu^2＋. Furthermore, a significant downregulation of the enzymes of AsA biosynthesis and the antioxidant system was found. This evidence suggests that excessive Cu^2＋-elevated reactive oxygen species （ROS） production is caused by upregulated PLD that elevates the activity of NADPH oxidase and its collapsed antioxidant systems that scavenges ROS.

关键词： ascorbic acid Cu^2+ nicotinamide adenine dinucleotide phosphate oxidase phospholipase D reactive oxygen species.

Kiwifruit(Actinidia chinensis 'Hongyang') cytosolic ascorbate peroxidases(AcAPX1 and AcAPX2) enhance salinity tolerance in Arabidopsis thaliana

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Journal of Integrative Agriculture 2022年第4期21卷 1058-1070页

作者： GUO Xiu-hong HE Yan ZHANG Yu WANG Yi HUANG Sheng-xiong LIU Yong-sheng LI Wei Key Laboratory for Bio-resource and Eco-environment of Ministry of Education College of Life Sciences/State Key Laboratory of Hydraulics and Mountain River EngineeringSichuan UniversityChengdu 610064P.R.China School of Horticulture Anhui Agricultural UniversityHefei 230036P.R.China School of Food and Biological Engineering Hefei University of TechnologyHefei 230009P.R.China

Ascorbate peroxidase(APX) plays a key role in scavenging reactive oxygen species(ROS) in higher plants. However, there is very little information available on the APXs in kiwifruit(Actinidia), which is an economically and nutritionally important horticultural crop with exceptionally high ascorbic acid(AsA) accumulation. This study aims to identify and characterize two cytosolic APX genes(AcAPX1 and AcAPX2) derived from A. chinensis ‘Hongyang’. The constitutive expression pattern was determined for both AcAPX1 and AcAPX2, and showed relatively higher expression abundances of AcAPX1 in leaf and AcAPX2 in root. Transcript levels of AcAPX1 and AcAPX2 were increased in kiwifruit roots treated with Na Cl. Subcellular localization assays using GFP-fusion proteins in Arabidopsis protoplasts showed that both AcAPX1 and AcAPX2 are targeted to the cytosol. Recombinant AcAPX1 or AcAPX2 proteins were successfully expressed in the prokaryotic expression system and their individual ascorbate peroxidase activities were determined. Finally, constitutive over-expression of AcAPX1 or AcAPX2 could dramatically increase total As A, glutathione level and salinity tolerance under Na Cl stress in Arabidopsis thaliana. Our findings revealed that cytosolic AcAPX1/2 may play an important protective role in the responses to unfavorable environmental stimuli in kiwifruit.

关键词： Actinidia ascorbic acid ascorbate peroxidase salinity