翻转课堂在“仪器分析”教学中的应用实践
作者:
夏莉;董萌;雷存喜
期刊:
高教学刊 ,2017年(21):131-133 ISSN:2096-000X
作者机构:
湖南城市学院 材料与化学工程学院,湖南 益阳,413099;[夏莉; 董萌; 雷存喜] 湖南城市学院
关键词:
仪器分析;翻转课堂;教学视频;实验教学
摘要:
"仪器分析"是化学类专业的核心专业课程之一。在"仪器分析"的课堂教学和实验教学中引入翻转课堂教学模式,结合视频学习、随堂测试、课堂讨论、重点讲解等教学方法和手段,对传统教学模式进行优化和改革。实际应用效果表明,翻转课堂的实施可提升教学质量和教学效率,有助于提高学生的学习积极性和主动性,取得了良好的应用效果。
语种:
中文
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桑色素分子印迹传感器的制备与应用
作者:
Liu Rong;Long Li-Ping* ;Lei Cun-Xi;Wu Zhao-Yang;Liu Yu;...
期刊:
分析化学 ,2016年44(3):385-390 ISSN:0253-3820
通讯作者:
Long Li-Ping
作者机构:
[Long Li-Ping; Liu Rong; Liu Yu; Lei Cun-Xi; Li Si-Jia] Hunan City Univ, Coll Chem & Environm Engn, Yiyang 413000, Peoples R China.;[Liu Rong; Wu Zhao-Yang] Hunan Univ, State Key Lab Chemo Biosensing & Chemometr, Changsha 410082, Hunan, Peoples R China.
通讯机构:
[Long Li-Ping] H;Hunan City Univ, Coll Chem & Environm Engn, Yiyang 413000, Peoples R China.
关键词:
分子印迹;桑色素;电化学传感器;电聚合
摘要:
以邻氨基酚(o-AP)为功能单体,桑色素为模板分子,基于分子间的相互作用力,在金电极表面电聚合制备具有特异性识别孔穴的桑色素分子印迹传感器膜。采用循环伏安法(CV)、差分脉冲伏安法(DPV)等研究了分子印迹膜的性能和分子印迹效应。探索了聚合膜配比及聚合扫描圈数对传感器性能的影响,优化了洗脱时间和印迹时间。比较了此传感器对其结构相似物的选择性响应,发现其对桑色素检测具有良好的选择性。在最佳实验条件下,此传感器对桑色素浓度定量测定范围为0.05 ~ 1.70 μmol /L,线性方程为I(μA)= 1.0800lgc(mol /L)+ 9.3599,R= 0.9934,检出限为0.01 μmol /L。用此传感器测定黑茶样品中桑色素的含量,加标回收率为104.0% ~ 108.0%。
语种:
中文
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A graphene/ionic liquid modified selenium-doped carbon paste electrode for determination of copper and antimony
作者:
Liu, Rong;Lei, Cunxi* ;Zhong, Tongsheng;Long, Liping;Wu, Zhaoyang;...
期刊:
ANALYTICAL METHODS ,2016年8(5):1120-1126 ISSN:1759-9660
通讯作者:
Lei, Cunxi
作者机构:
[Zhong, Tongsheng; Zhang, Qi; Lei, Cunxi; Liu, Rong; Long, Liping] Hunan City Univ, Coll Chem & Environm Engn, Yiyang 413000, Peoples R China.;[Wu, Zhaoyang; Liu, Rong; Huan, Shuangyan] Hunan Univ, Coll Chem & Chem Engn, State Key Lab Chemo Biosensing & Chemometr, Changsha 410082, Hunan, Peoples R China.
通讯机构:
[Lei, Cunxi] H;Hunan City Univ, Coll Chem & Environm Engn, Yiyang 413000, Peoples R China.
摘要:
A graphene (GN) and ionic liquid (IL) modified selenium-doped carbon paste electrode (GN/IL/Se/CPE) was established to simultaneously determine trace Cu(ii) and Sb(iii) by differential pulse voltammetry (DPV). Several parameters which affect the stripping current response were investigated and optimized, including the proportion of Se powder, concentration of hydrochloric acid, deposition time and deposition potential. The DPV curves were recorded by simultaneous deposition of Cu(ii) and Sb(iii) at -0.4 V for 50 s in a supporting electrolyte solution HCl of 0.30 mol L-1. Under the optimized conditions, the GN/IL/Se/CPE sensor has a good linear response in the range of 2.0 × 10-6 to 7.0 × 10-5 mol L-1 for Cu(ii) and 2.0 × 10-6 to 4.0 × 10-5 mol L-1 for Sb(iii). The detection limits were 6.6 × 10-7 mol L-1 for Cu(ii) and 4.3 × 10-7 mol L-1 for Sb(iii). The sensor showed favorable stability and higher sensitivity. The present work extends the scope of these devices as mercury-free sensors and can be used to detect Cu(ii) and Sb(iii) simultaneously. © The Royal Society of Chemistry 2016.
语种:
英文
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HPLC法测定茯砖茶中芦丁含量
作者:
刘蓉;雷存喜;赵运林;刘石泉;陈丹
期刊:
北京农业 ,2012年(09):4-5 ISSN:1000-6966
作者机构:
湖南城市学院化学与环境工学院,湖南益阳,413000;[刘蓉; 刘石泉; 赵运林; 雷存喜; 陈丹] 湖南城市学院
关键词:
茯砖茶;芦丁
摘要:
建立了茯砖茶中主要黄酮类物质芦丁的高效液相色谱测定方法.采用Hypersil ODS色谱柱C18色谱柱,流动相:A乙腈;B磷酸溶液(pH=2.5),梯度洗脱,流速1.0 mL/min,检测波长258 nm,样量为20 μL,柱温30℃.对照品芦丁的回归方程Y=16 007.7 ρB(μg/mL)-11 115.2,R=0.999 3,线性范围为10.000-80.000 mg/L,平均回收率99.010 0%,RSD为2.070 0%.测得茯砖茶中芦丁含量为0.143 5%,RSD为3.490 0%.该方法简便、快速、准确,可用于茯砖茶中芦丁含量的测定.
语种:
中文
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蒌蒿(Artemisia selengensis)对土壤中镉的胁迫反应及修复潜力研究
作者:
董萌;赵运林;雷存喜;戴枚斌;易合成;...
期刊:
环境科学学报 ,2012年32(6):1473-1480 ISSN:0253-2468
通讯作者:
Zhao, Y.
作者机构:
[赵运林; 雷存喜; 库文珍] Department of Chemistry and Environment Engineering, Hunan City University, Yiyang 413000, China;College of Biology and Technology, Hunan Agricultural University, Changsha 410128, China;[戴枚斌; 易合成] Administration Bureau of South Dongting Lake Nature Reserve, Yiyang 411000, China;[董萌] Department of Chemistry and Environment Engineering, Hunan City University, Yiyang 413000, China<&wdkj&>College of Biology and Technology, Hunan Agricultural University, Changsha 410128, China
通讯机构:
Department of Chemistry and Environment Engineering, Hunan City University, China
关键词:
镉;蒌蒿;生长状况;富集特征;植物修复
摘要:
以洞庭湖湿地新发现的Cd高富集植物—蒌蒿(Artemisiaselengensis)为试验材料,采用盆栽方式,系统研究了蒌蒿在生长期内对cd的性状反应及富集特征.结果表明,大于40mg·kg^-1的Cd胁迫对蒌蒿叶片伤害明显,且导致生物量下降,但植株在100mg·kg^-1胁迫下可完成生活史,对Cd有较强的耐受能力;土壤中有效态Cd的含量仅占土壤全Cd含量的15.3%-37.1%;相同胁迫浓度下,各生长阶段的植株体内Cd含量差别不大,但由于生物量的原因,幼苗期对Cd的提取量显著小于其他时期,其中40-60mg·kg^-1的Cd处理可使蒌蒿地上部分Cd含量达492-588mg·kg^-1(成株期),且植株对该浓度范围的Cd污染去除效果最好;蒌蒿可作为对湿地土壤Cd污染较理想的修复植物加以研究和利用.
语种:
中文
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湖南地区茯砖茶中金花菌的分离鉴定
作者:
彭晓赟;章卫民;刘淑云;雷存喜;周小梅;...
期刊:
菌物研究 ,2011年(3):157-161 ISSN:1672-3538
作者机构:
湖南城市学院化学与环境工程系益阳黑茶研究所;[章卫民] 广东省微生物研究所;[刘石泉; 周小梅; 赵运林; 彭晓赟; 雷存喜; 刘淑云] 湖南城市学院
关键词:
茯砖茶;金花菌;冠突散囊菌;子囊孢子;分生孢子;湖南地区
摘要:
对湖南地区茯砖茶上"金花菌"的菌落特征、形态特征进行了研究,并运用扫描电镜观察了其子囊孢子和分生孢子的发育过程,鉴定其为冠突散囊菌(Eurotium cristatum)。
语种:
中文
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茯砖茶茶叶品质和保健功能的研究概况
作者:
彭晓赟;赵运林;何小书;雷存喜;刘石泉;...
期刊:
湖南城市学院学报(自然科学版) ,2011年20(4):45-48 ISSN:1672-7304
作者机构:
湖南城市学院化学与环境工程学院益阳黑茶研究所,湖南益阳,413000;慈利职业中等专业学校,湖南慈利,427200;湖南农业大学食品科学与技术学院,长沙,410128;[董萌; 周晓梅; 刘石泉; 赵运林; 彭晓赟; 雷存喜] 湖南城市学院;[胡治远] 湖南农业大学
关键词:
茯砖茶;冠突散囊菌;鉴定;品质;保健功能
摘要:
茯砖茶是古老茶类黑茶中的高档品种,"金花菌"是茯砖茶发花过程的主要微生物,通过它的代谢作用改善了茶叶的品质,并赋予了茯砖茶特有的保健功能.综述了茯砖茶中优势菌及其与茯砖茶品质之间的关系以及茯砖茶保健功能的研究概况,并对今后茯砖茶研究的发展方向进行了展望.
语种:
中文
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Anatase TiO2 Nano-particles Preparation With Neutralization Hydrolysis Technique and Photocatalytic Performance
作者:
Lin, Li* ;Lei, Cunxi;Zhou, Jicheng
期刊:
Advanced Materials Research ,2010年113-116(229):1639-1643 ISSN:1022-6680
通讯作者:
Lin, Li
作者机构:
[Lei, Cunxi; Lin, Li] Hunan City Univ, Dept Chem & Environm Engn, Hunan City 413000, Peoples R China.;[Zhou, Jicheng] Xiangtan Univ, Dept Chem Engn, Xiangtan 411105, Peoples R China.
通讯机构:
[Lin, Li] H;Hunan City Univ, Dept Chem & Environm Engn, Hunan City 413000, Peoples R China.
会议名称:
2010 International Conference of Environment Materials and Environment Management(2010年环境材料与环境管理国际学术会议 EMEM 2010)
会议时间:
2010-07-24
会议地点:
哈尔滨
会议主办单位:
[Lin, Li;Lei, Cunxi] Hunan City Univ, Dept Chem & Environm Engn, Hunan City 413000, Peoples R China.^[Zhou, Jicheng] Xiangtan Univ, Dept Chem Engn, Xiangtan 411105, Peoples R China.
会议论文集名称:
2010 International Conference of Environment Materials and Environment Management(2010年环境材料与环境管理国际学术会议 EMEM 2010)论文集
关键词:
neutralization hydrolysis;TiO2 nanomaterial;photocatalytic
摘要:
A neutralization hydrolysis route has been used to synthesize titanium oxide nanoparticles. Transmission electron microscopy(TEM) and X-ray diffraction(XRD) characterization results showed the TiO2 nanoparticles were single anatase phases when calcined at 600°C-800°for 2h. The particle diameter ranged from 15 to 30nm. The pH value was key factor for precursor composition. When pH value 2-4, the H2TiO3 precursor with low agglomeration was obtained. As-prepared anatase TiO 2 nanoparticles, during photodegradation of methylic orange under UV-light irradiation(λ=254nm), exhibited excellent activity, more than 95.5% methylic orange was degraded in 1h. © (2010) Trans Tech Publications, Switzerland.
语种:
英文
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基于硅溶胶-凝胶/褐藻酸钠复合膜包埋酪氨酸酶的苯酚传感器研制
作者:
Lei Cun-Xi* ;Shen Guo-Li;Yu Ru-Qin
期刊:
分析化学 ,2007年35(2):273-276 ISSN:0253-3820
通讯作者:
Lei Cun-Xi
作者机构:
[Lei Cun-Xi] Hunan Univ, State Key Lab Chemo Biosensing & Chemometr, Changsha 410082, Peoples R China.;Hunan City Univ, Dept Chem & Environm Engn, Yiyang 413049, Peoples R China.
通讯机构:
[Lei Cun-Xi] H;Hunan Univ, State Key Lab Chemo Biosensing & Chemometr, Changsha 410082, Peoples R China.
关键词:
褐藻酸钠;无机/有机杂化膜;酪氨酸酶;电化学苯酚传感器
摘要:
将天然聚合物褐藻酸钠添加到无机硅溶胶-凝胶膜,获得一种新型的无机/有机杂化膜.用此杂化膜包埋酪氨酸酶,制备电化学苯酚传感器.研究表明:硅溶胶-凝胶/褐藻酸钠复合膜能有效克服纯无机溶胶-凝胶膜的脆性;避免膜的裂开;提供生物酶所适宜的微环境;有效保持所固定酶的生物活性.所制备的传感器测定苯酚的线性响应范围为3.4~93.1 μmol/L,其线性回归方程i(μA)=0.0774C(μmol/L)+0.1616, r=0.9980.检出限为1.33 μmol/L.
语种:
中文
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Ruthenium tris(2,2′)bipyridyl-modified oxidized boron-doped diamond electrode for the determination of Vitamin B6 in the presence of Vitamins B1 and B2
作者:
Wu, J;Lei, CX;Yang, HF;Wu, XM;Shen, GL* ;...
期刊:
Sensors and Actuators B-Chemical ,2005年107(2):509-515 ISSN:0925-4005
通讯作者:
Shen, GL
作者机构:
[Shen, GL] Hunan Univ, Coll Chem & Chem Engn, State Key Lab Chemobiosensing & Chemometr, Changsha 410082, Hunan, Peoples R China.;Hunan City Univ, Dept Chem & Environm Engn, Yiyang 413049, Peoples R China.
通讯机构:
[Shen, GL] H;Hunan Univ, Coll Chem & Chem Engn, State Key Lab Chemobiosensing & Chemometr, Changsha 410082, Hunan, Peoples R China.
关键词:
oxidized boron-doped diamond electrode;Vitamin B-6;ruthenium (III) tris(2,2 ’)bipyridyl (Ru(bpy)(3)(3+));THIN-FILM ELECTRODES;ELECTROCHEMICAL DETECTION;ELECTROOXIDATION;CHROMATOGRAPHY;CARBON
摘要:
The preparation and electrochemical characteristics of oxidized boron-doped diamond electrode modified by ruthenium tris(2,2′)bipyridyl (Ru(bpy) <inf>3</inf><sup>3+</sup>) are described. The Ru(bpy)<inf>3</inf> <sup>3+</sup>-modified boron-doped diamond electrode has strong electrocatalytic effects on the redox of Vitamin B<inf>6</inf> (VB<inf>6</inf>). The oxidization and reduction peak potentials of VB<inf>6</inf> are 167.6 and -113 mV, respectively. In the presence of a large amount of Vitamins B<inf>1</inf> (VB<inf>1</inf>) and B<inf>2</inf> (VB<inf>2</inf>), the redox peak potentials of VB<inf>6</inf> shift slightly while VB<inf>1</inf> and VB<inf>2</inf> are not reduced or oxidized on the modified electrode. The catalytic mechanism and the effect of the film thickness were discussed. The influence of various experimental parameters on the Ru(bpy)<inf>3</inf><sup>3+</sup>-modified boron-doped diamond electrode in VB<inf>6</inf> solution (i.e. frequency and amplitude of SWV, pH and scan rate) was investigated. A sensitive square wave voltammetric response for VB<inf>6</inf> is obtained covering a linear range from 0.2775 μM to 0.3686 mM with a detection limit of 6.319 ×10 <sup>-8</sup> mol/L in the presence of a large amount of VB<inf>1</inf> and VB<inf>2</inf>. The modified electrode showed good stability and reproducibility with satisfactory recovery results. The determination of VB<inf>6</inf> in tablets using this modified electrode showed promising results compared with the traditional methods. ©2004 Elsevier B.V. All rights reserved.
语种:
英文
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The integration of gold nanoparticles with semi-conductive oligomer layer for development of capacitive immunosensor
作者:
Hu, SQ;Xie, ZM;Lei, CX;Shen, GL* ;Yu, RQ
期刊:
Sensors and Actuators B-Chemical ,2005年106(2):641-647 ISSN:0925-4005
通讯作者:
Shen, GL
作者机构:
[Shen, GL] Hunan Univ, Coll Chem & Chem Engn, State Key Lab Chemo Biosensing & Chemometr, Changsha 410082, Peoples R China.;Zhu Zhou Teachers Coll, Dept Chem, Zhuzhou 412007, Peoples R China.;Hunan City Coll, Dept Chem & Environm Engn, Yiyang 413049, Peoples R China.
通讯机构:
[Shen, GL] H;Hunan Univ, Coll Chem & Chem Engn, State Key Lab Chemo Biosensing & Chemometr, Changsha 410082, Peoples R China.
关键词:
Capacitive immunosensor;Gold nanoparticles;Oligomer layer;Transferrin
摘要:
A new strategy for constructing the capacitance immunosensor was developed based on gold nanoparticles, which were employed as the platform to immobilize immunospecies. Gold nanoparticles were fixed on the gold electrode, on which the oligomer layer of o-aminobenzenthiol was pre-formed via electrochemical polymerization. An interesting immunospecies was loaded on gold nanoparticles to complete the fabrication of capacitance immunosensor. The changes in morphology of the gold electrode during the experiments were revealed by atomic force microscopy (AFM). The properties of the gold electrode were investigated by cyclic voltammetry, in the presence of an electro-active species as indictor. Also, potentiostatic pulse technique was used in order to evidence the changes of electrode capacitance. The feasibility of the proposed capacitive immunosensor was evaluated for a non-competitive heterogeneous immunoassay of transferrin. The assay covers a relatively large dynamic range of 0.125–100 ng/ml transferrin with a detection limit of 80 pg/ml and a relative high signal-to-noise ratio.
语种:
英文
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An H2O2 biosensor based on immobilization of horseradish peroxidase labeled nano-Au in silica sol-gel/alginate composite film
作者:
Lei, CX* ;Long, LP;Can, ZL
期刊:
Analytical Letters ,2005年38(11):1721-1734 ISSN:0003-2719
通讯作者:
Lei, CX
作者机构:
[Lei, CX; Long, LP; Can, ZL] Hunan City Univ, Dept Environm Chem & Engn, Yiyang 413049, Peoples R China.
通讯机构:
[Lei, CX] H;Hunan City Univ, Dept Environm Chem & Engn, Yiyang 413049, Peoples R China.
关键词:
Amperometric biosensor;HRP-nano-Au;Hydrogen peroxide;Silica sol-gel/alginate composite material
摘要:
A novel approach to assemble an H2O2 amperometric biosensor was introduced. The biosensor was constructed by entrapping horseradish peroxidase (HRP) labeled nano-scaled particulate gold (nano-Au) (HRP-nano-Au electrostatic composite) in a new silica sol-gel/alginate hybrid film using glassy carbon electrode as based electrode. This suggested strategy fully merged the merits of sol-gel derived inorganic-organic composite film and the nano-Au intermediator. The silica sol-gel/alginate hybrid material can improve the properties of conventional sol-gel material and effectively prevent cracking of film. The entrapment of HRP in the form of HRP-nano-Au can not only factually prevent the leaking of enzyme out of the film but also provide a favorable microenvironment for HRP. With hydroquinone as an electron mediator, the proposed HRP electrode exhibited good catalytic activity for the reduction of H2O2. The parameters affecting both the qualities of sol-gel/alginate hybrid film and the biosensor response were optimized. The biosensor exhibited high sensitivity of 0.40 Al mol-1 cm-2 for H2O2 over a wide linear range of concentration from 1.22 × 10-5 to 1.46 × 10-3 mol L-1, rapid response of < 5 s and a detection limit of 0.61 × 10 -6 mol L-1. The enzyme electrode has remarkable stability and retained 86% of its initial activity after 45 days of storage in 0.1 mol L-1 Tris-HCl buffer solutions at pH 7. Copyright © Taylor & Francis, Inc.
语种:
英文
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An amperometric hydrogen peroxide biosensor based on immobilizing horseradish peroxidase to a nano-Au monolayer supported by sol–gel derived carbon ceramic electrode
作者:
Lei, CX;Hu, SQ;Gao, N;Shen, GL;Yu, RQ*
期刊:
Bioelectrochemistry ,2004年65(1):33-39 ISSN:1567-5394
通讯作者:
Yu, RQ
作者机构:
[Yu, RQ] Hunan Univ, Coll Chem & Chem Engn, State Key Lab Chemobiosensing & Chemometr, Changsha 410082, Peoples R China.;Hunan City Univ, Dept Chem & Environm Engn, Yiyang 413049, Peoples R China.;Zhuzhou Teachers Coll, Dept Chem, Zhuzhou 412007, Peoples R China.
通讯机构:
[Yu, RQ] H;Hunan Univ, Coll Chem & Chem Engn, State Key Lab Chemobiosensing & Chemometr, Changsha 410082, Peoples R China.
关键词:
Amperometric biosensor;Horseradish peroxidase;Hydrogen peroxide;Nano-Au monolayer
摘要:
A novel strategy for fabricating horseradish peroxidase (HRP)-based H <inf>2</inf>O<inf>2</inf> sensor has been developed by combining the merits of carbon sol-gel supporting matrix and nano-scaled particulate gold (nano-Au) mediator. The thiol functional group-derived carbon ceramic electrode (CCE) was first constructed using (3-mercaptopropyl) trimethoxy silane as sol-gel monomer. Then, the stable nano-Au monolayer was obtained through covalent linkage between nano-Au and thiol group on the surface of CCE. The experimental results showed that nano-Au monolayer formed not only could steadily immobilize HRP but also efficiently retain its bioactivity. Hydrogen peroxide was detected with the aid of hydroquinone mediator to transfer electrons between the electrode and HRP. The process parameters for the fabrication of the enzyme electrode and various experimental variables such as the operating potential, mediator concentration and pH of background electrolyte were explored for optimum analytical performance of the enzyme electrode. The biosensor had a fast response of less than 8 s with linear range of 1.22×10<sup>-5</sup> to 1.10×10<sup>-3</sup>mol l<sup>-1</sup> and a detection limit of 6.1×10<sup>-6</sup>mol l<sup>-1</sup>. The sensitivity of the sensor for H<inf>2</inf>O<inf>2</inf> was 0.29 A l mol<sup>-1</sup> cm<sup>-2</sup>. The activation energy for enzyme reaction was calculated to be 10.1 kJ mol <sup>-1</sup>. The enzyme electrode retained 75% of its initial activity after 5 weeks storage in phosphate buffer at pH 7. ©2004 Elsevier B.V. All rights reserved.
语种:
英文
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Highly selective dopamine determination by using carboxymethylated beta-cyclodextrin polymer film modified electrode
作者:
Yang, Y;Lei, CX;Liu, ZM;Liu, YL;Shen, GL;...
期刊:
Analytical Letters ,2004年37(11):2267-2282 ISSN:0003-2719
通讯作者:
Yu, RQ
作者机构:
[Yu, RQ] Hunan Univ, Coll Chem & Chem Engn, State Key Lab Chemobiosensing & Chemometr, Changsha 410082, Peoples R China.;Hunan City Univ, Dept Environm Chem & Engn, Yiyang, Peoples R China.
通讯机构:
[Yu, RQ] H;Hunan Univ, Coll Chem & Chem Engn, State Key Lab Chemobiosensing & Chemometr, Changsha 410082, Peoples R China.
关键词:
dopamine;ascorbic acid;beta-cyclodextrin polymer;carboxymethylated beta-cyclodextrin polymer;cyclic voltammetry;differential pulse voltammetry
摘要:
A highly selective and sensitive electrochemical sensor modified with carboxymethylated, beta-cyclodextrin (CM-beta-CDP) polymer film was fabricated for the determination of dopamine (DA) in the presence of ascorbic acid (AA). The electrochemical behavior of DA and AA at the chemically modified electrode was investigated by cyclic voltammetry (CV) and differential pulse voltammetry. The response mechanism of CM-beta-CDP film for DA was based on the combination of electrostatic and inclusion interaction of CM-beta-CDP for DA, which was distinguished from the response mechanism of the charged polymer film modified electrode that only relied upon the electrostatic interaction between charged polymer film and DA (or AA) to realize the separation of overlapping peak potential of DA and AA. The CM-beta-CDP film showed preferable analytical performance characteristics in catalytic oxidation of DA compared with the beta-CDP polymer film. Under optimized conditions, it was feasible for the electrode modified with the CM-beta-CDP film to selectively determine DA in the presence of a large excess of AA. A linear calibration plot was obtained over the range 0.8-60 muM with a sensitivity of 65 nA/muM and a detection limit (signal/noise (S/N) = 3) of 0.2 muM in the presence of 1.0mM AA. This electrochemical sensor showed excellent sensitivity, repeatability, stability, and recovery for the determination of DA. The interference of AA with the determination of DA could be efficiently eliminated.
语种:
英文
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Immobilization of enzymes on the nano-Au film modified glassy carbon electrode for the determination of hydrogen peroxide and glucose
作者:
Lei, CX;Wang, H;Shen, GL;Yu, RQ*
期刊:
Electroanalysis ,2004年16(9):736-740 ISSN:1040-0397
通讯作者:
Yu, RQ
作者机构:
[Yu, RQ] Hunan Univ, Coll Chem & Chem Engn, State Key Lab Chemobiosensing & Chemometr, Changsha 410082, Peoples R China.;Hunan City Coll, Dept Environm Chem & Engn, Yiyang 413049, Peoples R China.
通讯机构:
[Yu, RQ] H;Hunan Univ, Coll Chem & Chem Engn, State Key Lab Chemobiosensing & Chemometr, Changsha 410082, Peoples R China.
关键词:
Enzyme sensor;Nano‐Au film;Glassy carbon electrode;Hydrogen peroxide;Glucose
摘要:
A new enzyme-based amperometric biosensor for hydrogen peroxide was developed relying on the efficient immobilization of horseradish peroxidase (HRP) to a nano-scaled particulate gold (nano-Au) film modified glassy carbon electrode (GC). The nano-Au film was obtained by a chitosan film which was first formed on the surface of GC. The high affinity of chitosan for nano-Au associated with its amino groups resulted in the formation of nano-Au film on the surface of GC. The film formed served as an intermediator to retain high efficient and stable immobilization of the enzyme. H2O2,was detected using hydroquinone as an electron mediator to transfer electrons between the electrode and HRP. The HRP immobilized on nano-Au film maintained excellent electrocatalytical activity to the reduction of H2O2. The experimental parameters such as the operating potential of the working electrode, mediator concentration and pH of background electrolyte were optimized for best analytical performance of amperometry. The linear range of detection for H2O2 is from 6.1 x 10(-6) to 1.8 x 10(-3) mol L-1 with a detection limit of 6.1 mumol L-1 based on signal/noise = 3. The proposed HRP enzyme sensor has the features of high sensitivity (0.25 Almol(-1)cm(-2)), fast response time (t(90%) less than or equal to 10 s) and a long-term stability (> 1 month). As an extension, glucose oxidase (GOD) was chemically bound to HRP-modified electrode. A GOD/HRP bienzyme-modified electrode formed in this way can be applied to the determination of glucose with satisfactory performance.
语种:
英文
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A new electrochemical immunoassay strategy for detection of transferrin based on electrostatic interaction of natural polymers
作者:
Lei, CX;Wu, J;Wang, H;Shen, GL;Yu, RQ*
期刊:
Talanta ,2004年63(2):469-474 ISSN:0039-9140
通讯作者:
Yu, RQ
作者机构:
[Yu, RQ] Hunan Univ, State Key Lab Chemo Biosensing & Chemometr, Changsha 410082, Peoples R China.;Hunan City Univ, Dept Chem & Environm Engn, Yiyang 413049, Peoples R China.
通讯机构:
[Yu, RQ] H;Hunan Univ, State Key Lab Chemo Biosensing & Chemometr, Changsha 410082, Peoples R China.
关键词:
electrochemical immunoassay;electrostatic interaction;transferrin;alginate;chitosan-entrapped carbon paste electrode
摘要:
A new electrochemical immunoassay strategy was proposed based on electrostatic interaction of natural polymers. The chitosan-entrapped carbon paste electrode (CCPE) was used as the base electrode, alginates as carriers for the reactants and horseradish peroxidase (HRP) as enzyme label in the immunoassay. The immunoassay was firstly carried out using the homogeneous competitive immune format and a very high rate of immune reaction was reached since both reacting antibodies and antigens were in a solution phase. Subsequently quick heterogeneous separation of immune complexes attached to the alginates molecule from the solution phase was realized by making use of the strongly electrostatic attraction between the protonated amino groups of chitosans on the surface of CCPE and carboxylic groups of alginates. After washing the surface of CCPE, amperometric detection with hydroquinone and hydrogen peroxide as enzymatic substrates was carried out. A new surface of CCPE for repeated use in another assay can be obtained by polishing the original used one. The feasibility of the above approach was demonstrated using transferrin and transferrin-antibody as a model system. The dynamic concentration range for transferrin assay was 1.9 to 78.8 μg ml<sup>-1</sup>. ©2003 Elsevier B.V. All rights reserved.
语种:
英文
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Amperometric immunosensor for probing complement III (C3) based on immobilizing C3 antibody to a nano-Au monolayer supported by sol–gel-derived carbon ceramic electrode
作者:
Lei, CX;Yang, Y;Wang, H;Shen, GL;Yu, RQ*
期刊:
Analytica Chimica Acta ,2004年513(2):379-384 ISSN:0003-2670
通讯作者:
Yu, RQ
作者机构:
[Yu, RQ] Hunan Univ, Coll Chem & Chem Engn, State Key Lab Chemo Biosensing & Chemometr, Changsha 410082, Peoples R China.;Hunan City Univ, Dept Environm Chem & Engn, Yiyang 413049, Peoples R China.
通讯机构:
[Yu, RQ] H;Hunan Univ, Coll Chem & Chem Engn, State Key Lab Chemo Biosensing & Chemometr, Changsha 410082, Peoples R China.
关键词:
Amperometric immunosensor;Carbon ceramic electrode;Complement III;Nano-Au monolayer
摘要:
An electrochemical immunosensor based on nano-size particulate gold (nano-Au) monolayer as sensing interface has been developed for probing complement III (C3). The thiol functional group-derived carbon ceramic electrode (CCE) was firstly constructed using (3-mercaptopropyl) trimethoxy silane (MPTMOS) as sol-gel monomer. The stable nano-Au monolayer was obtained resulting from covalent combination between nano-Au and thiol group on the surface of CCE. The nano-Au monolayer formed was utilized as a sensing platform for the immobilization of C3 antibody (anti-C3) and subsequent immunoreaction. A competitive immunoassay format was adopted with horseradish peroxidase (HRP)-C3 as a tracer, hydroquinone and hydrogen peroxide as the enzymatic substrates. The dynamic concentration range for C3 is 0.08-5.6 μg ml-1. The feasibility of regenerating nano-Au monolayer for consecutive assays was demonstrated by a simple chemical treatment after each determination. The high stability of formed nano-Au monolayer, readily adsorptive immobilization of antibody on nano-Au monolayer, efficient activity retention of loading immunoreactants as well as the simple operation for the formation of nano-Au monolayer make proposed methodology an attractive alternative for the designing new-type immunosensors. © 2004 Elsevier B.V. All rights reserved.
语种:
英文
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Immobilization of horseradish peroxidase to a nano-Au monolayer modified chitosan-entrapped carbon paste electrode for the detection of hydrogen peroxide
作者:
Lei, CX;Hu, SQ;Shen, GL;Yu, RQ*
期刊:
Talanta ,2003年59(5):981-988 ISSN:0039-9140
通讯作者:
Yu, RQ
作者机构:
[Yu, RQ] Hunan Univ, Coll Chem & Chem Engn, State Key Lab Chem Biosensing & Chemometr, Changsha 410082, Peoples R China.;Hunan City Coll, Dept Chem, Yiyang 413049, Peoples R China.;Zhuzhou Teachers Coll, Dept Chem, Zhuzhou 412007, Peoples R China.
通讯机构:
[Yu, RQ] H;Hunan Univ, Coll Chem & Chem Engn, State Key Lab Chem Biosensing & Chemometr, Changsha 410082, Peoples R China.
关键词:
Nano-Au monolayer;Chitosan-entrapped carbon paste electrode;Hydrogen peroxide;Enzyme sensor
摘要:
A procedure for fabricating an enzyme electrode has been described based on the effective immobilization of horseradish peroxidase (HRP) to a nano-scaled particulate gold (nano-Au) monolayer modified chitosan-entrapped carbon paste electrode (CCPE). The high affinity of chitosan entrapped in CCPE for nano-Au associated with its amino groups has been utilized to realize the use of nano-Au as an intermediator to retain high bioactivity of the enzyme. Hydrogen peroxide (H<inf>2</inf>O<inf>2</inf>) was determined in the presence of hydroquinone as a mediator to transfer electrons between the electrode and HRP. The HRP immobilized on nano-Au displayed excellent electrocatalytical activity to the reduction of H<inf>2</inf>O<inf>2</inf>. The effects of experimental variables such as the operating potential of the working electrode, mediator concentration and pH of measuring solution were investigated for optimum analytical performance by using an amperometric method. The enzyme electrode provided a linear response to hydrogen peroxide over a concentration range of 1.22 ×10<sup>-5</sup> -2.43 ×10<sup>-3</sup> mol 1<sup>-1</sup> with a sensitivity of 0.013 A 1 mol<sup>-1</sup> cm<sup>-2</sup> and a detection limit of 6.3 μmol 1<sup>-1</sup> based on signal per noise = 3. The apparent Michaelis-Menten constant (K<inf>m</inf><sup>app</sup>) for the sensor was found to be 0.36 mmol 1<sup>-1</sup>. The lifetime, fabrication reproducibility and measurement repeatability were evaluated with satisfactory results. The analysis results of real sample by this sensor were in satisfactory agreement with those of the potassium permanganate titration method. ©2003 Elsevier Science B.V. All rights reserved.
语种:
英文
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Synthesis of Methyl Benzoate Catalyzed by NaHSO_4·H_2O
作者:
文瑞明;雷存喜;丁亮中;俞善信
期刊:
合成化学 ,2003年11(1):89-92 ISSN:1005-1511
作者机构:
[文瑞明; 雷存喜; 丁亮中; 俞善信] Department of Chemistry,Hunan City College
关键词:
催化合成;酯化;苯甲酸;甲醇;苯甲酸甲酯;硫酸氢钠
摘要:
以NaHSO4*H2O催化苯甲酸与甲醇的酯化反应,合成了苯甲酸甲酯.研究结果表明,NaHSO4*H2O具有较高的催化活性.考察了苯甲酸/甲醇摩尔比、催化剂用量及反应时间对酯产率的影响.在优化反应条件[n(苯甲酸)∶n(甲醇)∶n(NaHSO4*H2O)=1∶2∶0.29,回流8h]下,苯甲酸甲酯产率达85.3%.
语种:
中文
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Amperometric immunosensor for Schistosoma japonicum antigen using antibodies loaded on a nano-Au monolayer modified chitosan-entrapped carbon paste electrode
作者:
Lei, CX;Gong, FC;Shen, GL;Yu, RQ*
期刊:
Sensors and Actuators B-Chemical ,2003年96(3):582-588 ISSN:0925-4005
通讯作者:
Yu, RQ
作者机构:
[Yu, RQ] Hunan Univ, Coll Chem & Chem Engn, State Key Lab Chemobiosensing & Chemometr, Changsha 410082, Peoples R China.;Hunan City Coll, Dept Chem & Environm Engn, Yiyang 413049, Peoples R China.
通讯机构:
[Yu, RQ] H;Hunan Univ, Coll Chem & Chem Engn, State Key Lab Chemobiosensing & Chemometr, Changsha 410082, Peoples R China.
关键词:
amperometric immunosensor;nano-Au monolayer;chitosan-entrapped carbon paste electrode;Schistosoma japonicum
摘要:
A new strategy to construct amperometric immunosensor for Schistosoma japonicum antigen (SjAg) assay based on nano-size particulate gold (nano-Au) monolayer as sensing platform has been described. The nano-Au monolayer was obtained through chitosan-entrapped carbon paste electrode (CCPE). The high affinity of chitosan entrapped in CCPE for nano-Au associated with its amino groups facilitated the formation of nano-Au monolayer on the surface of CCPE. A sequential competitive immunoassay format was performed on the nano-Au monolayer supported by CCPE using S. japonicum antibody (SjAb) and SjAg as a model system. The assay comprised first loading of SjAb on nano-Au monolayer, then blocking in BSA solution, followed by a competitive incubation in the buffer containing the SjAg (analyte) and SjAg labeled with horseradish peroxidase (HRP) and finally the amperometric detection with hydroquinone as an enzymatic substrate. The dynamic concentration range for SjAg assay is 0.11-22.4μgml<sup>-1</sup> with a detection limit of 0.06μgml <sup>-1</sup>. The feasibility of regenerating nano-Au monolayer for consecutive assays was demonstrated by a simple chemical treatment after each determination. The simple manipulations of construction of nano-Au monolayer, low-cost and improved sensitivity are main features of proposed immunosensing method. ©2003 Elsevier B.V. All rights reserved.
语种:
英文
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