电化学 纳米金修饰电极检测VC和尿酸

Published:April 02,2011

LETTER https://www.wendangku.net/doc/2611552954.html,/ac

Electrochemical Sensing Using Quantum-Sized Gold Nanoparticles

S.Senthil Kumar,Kyuju Kwak,and Dongil Lee*

Department of Chemistry,Yonsei University,Seoul 120-749,Korea

b

Supporting Information R

ecent advances in the synthesis of ultrasmall gold nanoparticles protected with organothiolate (SR)have opened the possibility to synthesize stable,atomically monodisperse gold nanoparticles.1à4Au 25(SR)18,Au 38(SR)24,and Au 144(SR)60are the examples of the quantum-sized gold nanoparticles that exhibit discrete electronic states and quantum con ?nement e ?ects.5,6These nanoparticles have received considerable attention recently because of their unique size-dependent electrochemical,optical,and catalytic properties.1à9Much progress has been made toward understanding their structures and fundamental physical and chemical properties.For example,electrochemical and optical study of the Au 25nanoparticles has revealed that Au 25has the highest occupied molecular orbital (HOMO)àlowest unoccupied molecular orbital (LUMO)gap of ca.1.33eV,representing the molecule-like property.5However,the technological application of such nanoparticles is still scarce.7à9It will be of great interest to utilize these functional materials in technolog-ical areas such as nanoelectronics,optoelectronics,and sensors since these nanoparticles could exhibit unique properties that di ?er sub-stantially from the corresponding atoms and bulk materials.Herein,we report the ?rst utilization of the quantum-sized Au 25nanoparticles in electrocatalysis and electrochemical sensing.

The sol àgel technique has been used to immobilize gold nanoparticles to form a modi ?ed electrode.10à12Gold nanoparticles employed for electrochemical sensing thus far were,however,redox inactive nanoparticles with core diameters usually larger than 3nm and,thus,they were entrapped into the sol àgel network along with redox mediators or redox enzymes.10à12The sol àgel matrix provides stability to the redox mediator or the enzyme that interacts selectively with the target analyte,and the gold nanoparticles act as tiny con-ductors.In the present study,the unique electrochemical properties of Au 25nanoparticles o ?er particular virtues for the development of the modi ?ed electrode in which Au 25can serve as an electronic conductor as well as a redox mediator.Highly monodisperse,hexanethiolate-pro-tected Au 25nanoparticles (Au 25)were synthesized and characterized as [Au 25(SC 6H 13)18]à(see Supporting Information for experimental details).Au 25nanoparticles were entrapped into the sol àgel network

by the hydrolysis of ethyltrimethoxy silane according to a literature procedure 13with slight modi ?cation.In a typical procedure,Au 25solution (10mg in 0.2mL of CH 2Cl 2)was mixed with 0.1mL of water containing 25%(v/v)glutaraldehyde and 0.2mL of ethyltri-methoxy silane,and the mixture was sonicated for 30min.The resulting homogeneous solution was subsequently stored at room temperature for 2h.10μL of this mixture was then dropcast on the surface of a glassy carbon electrode (GCE,3mm diameter)and allowed to dry overnight at room temperature to form the modi ?ed sol àgel electrode (Au 25SGE).The Au 25SGE was then washed thoroughly with water and used as a working electrode.Scheme 1depicts the cartoon of Au 25SGE 14with the Au 25entrapped in the sol àgel network.

The square wave voltammogram (SWV)of Au 25in CH 2Cl 2shown in Figure 1A displays the redox characteristics of Au 25;three sets of well-de ?ned redox peaks with formal potentials at 0.62,0.31,and à1.33V vs Ag wire quasi-reference electrode (AgQRE)can be assigned to Au 251t/0,Au 250/1àand Au 251à/2àredox couples,respectively.1Cyclic voltammogram (CV)of the Au 25SGE in 0.1M KCl (Figure 1B)also shows well-de ?ned and reversible redox peaks with formal potential at 0.34V vs Ag/AgCl corresponding to Au 250/1àcouple.The redox peaks of Au 251t/0couple are not well-resolved,and they appear as a small shoulder around 0.43V.The reason for this behavior is unclear at this time.It could re ?ect the fact that small peak spacings between Au 251t/0and Au 250/1àcouples are expected when the dielectric constant of the medium is higher.5It could also be due to the fact that limited charge-compensating counterions are available in the sol àgel network for Au 251t/0upon the ?rst oxidation (Au 250/1à)reaction,as has been observed in the voltammogram of a Langmuir monolayer of similar particles.15The ?rst oxidation (Au 250/1à)appears,however,to be very stable and reproducible;the peak potentials and peak currents of the Au 25SGE

Received:February 14,2011Accepted:April 2,2011ABSTRACT:This paper describes the electrocatalytic activity of quantum-sized thiolate protected Au 25nanoparticles and their use in electrochemical sensing.The Au 25?lm modi ?ed electrode exhibited excellent mediated electrocatalytic activity that was utilized for amperometric sensing of biologically relevant ana-lytes,namely,ascorbic acid and uric acid.The electron transfer dynamics in the Au 25?lm was examined as a function of Au 25concentration,which manifested the dual role of Au 25as an electronic conductor as well as a redox mediator.The electron

transfer study has further revealed the correlation between the electronic conductivity of the Au 25?lm and the sensing

sensitivity.

were found to remain unaltered for25continuous cycles(Figure1B), re?ecting the stable immobilization of the Au25in the solàgel network.

The electrocatalytic activity of the Au25SGE toward the oxidation of biologically relevant analytes,namely,ascorbic acid (AA)and uric acid(UA),has been examined.Figure2shows the CVs of Au25SGE and bare GCE(inset to Figure2)recorded in the absence and presence of the analytes in0.1M KCl.As shown in the?gures,there is a dramatic enhancement in the anodic peak current at the Au25SGE(curves bàf)upon the addition of analytes in1μM increments,whereas only a slight increase in the anodic current was observed at the bare GCE even after the addition of5μM of the analytes(curve h).Both AA and UA are known to undergo irreversible oxidation,16and thus,the en-hancement was observed only in the anodic current.Moreover, AA and UA were found to undergo oxidation,respectively,at380 and405mV,signi?cantly lower potentials at the Au25SGE than those at the bare GCE,as compared in Table1.The oxidation potentials of AA and UA at the Au25SGE are also considerably lower than those at the bare gold electrode,which were found to be460and574mV for AA and UA,respectively.The decrease in the potential for oxidation of these analytes to a potential closer to the oxidation potential of Au25,accompanied with an en-hancement in anodic current,clearly demonstrates the mediated electrocatalytic activity17of the immobilized Au25according to the following reactions:

Au25àf Au250e1TAu250tanalyteereducedTf Au25àtanalyteeoxidizedTe2TThe Au25nanoparticles in the solàgel network are?rst oxidized at the electrode(eq1).In the presence of analyte,the oxidized Au250 electrocatalytically oxidizes the analyte while it is reduced to Au25à(eq2).The unique electronic structure of Au25nanoparticles has been computed,18,19which reveals uneven charge distribution between the Au13core and the Au12shell.The electron-de?cient Au12shell and low-coordinate surface gold atoms9appear to be responsible for the observed electrocatalytic activity of the Au25 nanoparticles.The regeneration of Au25àwould result in an increase in the anodic current with increasing analyte concentra-tion.In addition,the oxidation of AA and UA at the Au25SGE (Figure2A,B)shows only one peak nearer to the oxidation peak of the mediator(Au25),indicating that all the available AA and UA undergo mediated electrocatalytic oxidation at the Au25SGE.

As can be seen in the calibration graphs in Figure2,the increases in the anodic peak currents were found to vary linearly with the concentration of the analyte added for both analytes. The amperometric sensing performance of Au25SGE summar-ized in Table1shows that the Au25SGE can be employed for the amperometric determination of these analytes over a good linear range with low detection limit and high sensitivity.The obtained linear range,detection limit,and sensitivity are comparable or better than the recently reported electrochemical sensors for the determination of these analytes.16,20à22To the best of our knowledge,this is the?rst result demonstrating amperometric sensing based on a redox-active gold nanoparticle.

As noted above,Au25could play the dual role as an electronic conductor as well as a redox mediator.In order to gain further insights into the role of Au25as a conductor,we examined the elec-tron transport in the Au25SGE as a function of the Au25concentra-tion(C).24Stable voltammetric responses were observed for all the concentrations in the range from3.94to15.97mM.A representative

Scheme1.Mechanism Depicting the Mediated Electrocata-lytic Oxidation and Ensuing Electron Transport Across the Entrapped

Au25in

Au25SGE

Figure1.(A)SWV of Au25in CH2Cl2containing0.1M Bu4NPF6at Pt working electrode.(B)CV of the Au25SGE for25continuous cycles in 0.1M KCl at20

mVsà1.Figure2.Voltammograms demonstrating the electrocatalytic oxidation of(A)ascorbic acid and(B)uric acid in0.1M KCl at20mVsà1;(a)CV of Au25SGE in the absence of analyte,(bàf)in the presence of1,2,3,4, and5μM of the analyte,(g)CV of bare GCE in the absence of analyte, and(h)in the presence of5μM of analyte,and calibration graphs for the determination of(C)ascorbic acid and(D)uric acid from the voltammograms of Au25SGE.

voltammetric response of the Au25SGE(C=15.97mM)at varying scan rate is shown in Figure S4(Supporting Information).Both anodic and cathodic peak currents for all the modi?ed electrodes made with di?erent Au25concentrations were found to vary linearly with the square root of scan rate from2to100mVsà1(Figure S5,Support-ing Information),indicating the electron transport in the?lm is a di?usion-controlled process.The apparent di?usion coe?cients (D APP)were calculated from the peak currents.25The di?usion pro-cess may involve one or both of physical di?usion(D PHYS)and electron hopping di?usion(D E)between Au25cores(i.e.,electron self-exchange)in the?lm.The possible electrocatalytic reaction between the oxidized Au250and analyte and ensuing electron transport process across the Au25?lm is shown in Scheme1.To calculate the electron hopping rates from D E,we make the assumption that D E.

D PHYS.This is entirely reasonable considering the Au25SG

E structure (Scheme1)in which Au25nanoparticles are entrapped in the polymer network.Thus,the self-exchange rate constant(k EX)of the Au250/àcouple in the?lm can be calculated from D E using26,27

D APP?D PHYStD E%D E?k EXδ2C=6e3Twhereδis the centeràcenter Au25core separation.The calculated D

E and k EX are plotted versus the Au25concentration in Figure3,and values are listed in Table S1(Supporting Information).

The structurally well-de?ned Au25SGE opens the way to unravel the e?ect of the electronic conductivity of the?lm on electrochemical sensing.As can be seen in Figure3,both D E and k EX increase dramatically at lower Au25concentrations and gradually reach the maximum at concentrations higher than9.23mM.The consequence of this behavior is well re?ected in the sensitivity results for ascorbic acid(S AA)and uric acid(S UA).Both S AA and S UA show more than a 25-fold increase as the concentration increases from3.94mM to 9.23mM by2.3-fold,whereas S AA and S UA increase almost linearly with concentration at concentrations higher than9.23mM.These results clearly indicate that the sensitivity is dominantly controlled by the electron transfer dynamics in the?lm at lower Au25concentra-tions.In addition,the fact that the sensitivity increases linearly with concentration at higher concentrations indicates that all Au25 nanoparticles in the?lm are electroactive and electronically well-connected with each other.Finally,the dependence of k EX on Au25 concentration provides new insights into the electron hopping mechanism in the?lm.When the Au25concentration is higher than 9.23mM,the k EX reaches the maximum rate which appears to be limited by the tunneling rate through the hexanethiolate ligands between the Au25cores.The maximum k EX of2.27?108Mà1sà1 (Table S1,Supporting Information)compares very well with those obtained from network?lms of gold nanoparticles.28At lower concentrations(C<9.23mM),the electron hopping rate appears to be limited by the mass transport rate of Au25to form a precursor complex for electron transfer.26This interpretation is well supported by the structural data of Au25SGEs in Table S1(Supporting Infor-mation)in which the average Au25centeràcenter distances29seem to be too long for the electron transfer to occur at that equilibrium distance.

In summary,we have shown that redox-active Au25nanopar-ticles can be utilized to develop amperometric sensors based on their excellent electrocatalytic activity.The electron transfer dynamics study of the Au25modi?ed electrode manifests that Au25nanopar-ticles play the dual role as an electronic conductor as well as a redox mediator.The electron transfer study further provides the?rst quantitative results,revealing the correlation between the electron transfer dynamics in the nanoparticle?lm and the sensing sensitivity. These studies are important to the frontier of fundamental science and also highly relevant to the potential technological applications of the quantum-sized gold nanoparticles.Another potential advantage of these sensors is that it may be possible to engineer the ligand shell of the nanoparticles to improve the selectivity.This will be pursued in the future work.

’ASSOCIATED CONTENT

b Supporting Information.Experimental details including synthesis and characterization of Au25and electron transport data.This material is available free of charge via the Internet at https://www.wendangku.net/doc/2611552954.html,.

’AUTHOR INFORMATION

Corresponding Author

*Phone:(t82)2-2123-5638.Fax:(t82)2-364-7050.E-mail: dongil@yonsei.ac.kr.Homepage:http://chem.yonsei.ac.kr/～nanomat/.

’ACKNOWLEDGMENT

This research was supported by World Class University(R32-2008-000-10217-0),Priority Research Centers(2009-0093823), and Basic Science Research(2010-0009244)Programs through

Table1.Electrocatalytic Activity and Amperometric Sensing Performance of Au25SGE

oxidation potentials(mV)a

analyte BareGCE(E1)Au25SGE(E2)E1-E2linear range(μM)LOD(μM)b S(μA/μM)c AA450380700.13à11.60.068 1.556 UA5104051050.13à7.50.071 1.489

a Oxidation potentials are compared at the analyte concentration of5μM.

b Limit of detection.

c Sensitivity of determination

of the analytes.23

Figure3.Dependence of electron di?usion coe?cient(D E),self-

exchange rate constant(k EX),and sensitivity of determination for

ascorbic acid(S AA)and uric acid(S UA)on the concentration of Au25.

the National Research Foundation of Korea(NRF)funded by the Ministry of Education,Science and Technology and Yonsei University Research Fund.

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(23)Linear range was obtained from the calibration graph(Figure S4,Supporting Information).Limit of detection was calculated using the formula(3σ/S),whereσand S represent the blank standard deviation and sensitivity of determination,respectively.σwas obtained from the change in the anodic peak current of the Au25SGE after the addition of a blank solution.

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(29)δwas calculated from C on the basis of a cubic lattice relation C=1/δ3N A,where N A is Avogadro’s number.

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银纳米修饰电极的制备及电化学行为 作者：姚爱丽， 吕桂琴， 胡长文， YAO Ai-Li， LU Gui-Qin， HU Chang-Wen 作者单位：北京理工大学理学院化学系,北京,100081 刊名： 无机化学学报 英文刊名：CHINESE JOURNAL OF INORGANIC CHEMISTRY 年，卷(期)：2006,22(6) 被引用次数：12次 参考文献(16条) 1.董绍俊;车广礼;谢远武化学修饰电极 2003 2.Nada M D;David M B查看详情 2001 3.Sandmamn G;Dietz H查看详情 2000 4.高迎春;李茂国;王广凤银纳米修饰电极的制备及其对灿烂甲酚蓝的催化研究[期刊论文]-Chin J Anal Lab 2004(12) 5.Sarkar J;Pal P;Talapatra G B Adsorption of 2-aminobenzothiazole on colloidal silver particles: An experimental and theoretical surface-enhanced Raman scattering study[外文期刊] 2005(26) 6.Vukovic V V;Nedeljkovic J查看详情 1993(04) 7.Gole A;Sainkar S R查看详情 2000(05) 8.Kumar A;Mandale A B;Sastry Sequential electrostatic assembly of amine-derivatized gold and carboxylic acid-derivatized silver colloidal particles on glass substrates[外文期刊] 2000(17) 9.Cheng L;Dong S J查看详情 2000 10.周延秀;朱果逸;汪尔康查看详情 1994(03) 11.Liu Z L;Wang X D;Wu H Y查看详情[外文期刊] 2005 12.Tang Z Y;Liu S Q;Dong S J查看详情 2001 13.曹楚南;张鉴清电化学阻抗谱导论 2002 14.阮北;鲁彬;童汝亭自组装巯基环肽单层膜修饰金电极电化学行为的研究[期刊论文]-J Hebei Normal University Natural Science Edition 2003(05) 15.孙向英;翁文婷荧光性自组装双层膜的制备及其性能研究[期刊论文]-Chemical Journal of Chinese Universities 2005(06) 16.Lu M;Li X H;Yu B Z查看详情[外文期刊] 2002 本文读者也读过(2条) 1.夏立新.宫科.汪舰.康笑博.佟胜睿.刘广业.XIA Li-Xin.GONG Ke.WANG Jian.KANG Xiao-Bo.TONG Sheng-Rui. LIU Guang-Ye用简便方法组装二维模板银纳米阵列[期刊论文]-化学学报2007,65(21) 2.吕桂琴.姚爱丽.郑传明.L(U) Gui-qin.YAO Ai-li.ZHENG Chuan-ming MPA包覆的银纳米粒子修饰电极制备和电化学表征[期刊论文]-北京理工大学学报2006,26(10) 引证文献(12条) 1.王耀先.贺国旭.张秋霞.王香.胡中爱铝基氪化铝模板制备Ag纳米线及其电化学性质[期刊论文]-化工新型材料2013(1) 2.周闻云.陈艳玲.韩清.贾玉萍抗坏血酸在纳米银DNA修饰电极上的电化学行为研究[期刊论文]-分析科学学报

降尿酸的药物及分类

降尿酸的药物及分类 第一类为抑制尿酸合成的药。其代表药是别嘌醇(别嘌呤醇)。别嘌醇可用于各种年龄的原发性和继发性痛风病人，不受肾功能的限制，故痛风病人合并肾功能不全、肾结石及尿酸排出过多应首选本药。与促尿酸排泄药合用有协调作用。因药源充足、廉价，是较理想的降尿酸药之一。 别嘌醇为黄嘌呤氧化酶抑制剂，其结构类似次黄嘌呤，有较强的抑制黄嘌呤氧化酶作用，从而阻断次黄嘌呤向黄嘌呤、黄嘌呤向尿酸的代谢转化，可减少尿酸的生成，降低血尿酸浓度。该药能在PRPP(5-磷酸核糖-1-焦磷酸合成酶)存在时转变成相对应核苷酸，消耗PRPP使IMP(次黄嘌呤核苷酸)合成减少，从而可迅速降低血尿酸值，抑制痛风石和肾结石形成，并促进痛风石溶解。 适应证：⑴尿酸合成过多而导致的高尿酸血症。⑵肾功能严重损害而不能使增大的尿酸负荷排出者。⑶大剂量尿酸排泄促进剂无效或过敏，或不能耐受者。⑷肾尿酸结石反复形成者。⑸每日尿酸排泄超过5.9毫摩尔(1000毫克)者，易发生尿酸性肾结石的危险。⑹有较大的多部位痛风结节者(需要两种药联用以阻断尿酸的产生和增加尿酸的排泄)。⑺继发于骨髓增殖性疾病的高尿酸血症，特别是细胞毒制剂治疗前的患者，否则大量尿酸从肾排出，可发生急性肾小管阻塞。 用法：别嘌醇开始每天100毫克，每日2～3次口服，可逐渐增至每次200毫克，每日3～4次，每日最大剂量不超过600毫克为宜。血尿酸浓度正常后逐渐减至维持量，每次100毫克，每日1～2次。其副作用为过敏性皮疹、药物热、肠胃不适、白细胞及血小板减少、肝功能损害等。 注意事项：①需从小剂量开始，逐渐增加剂量，以免血尿酸浓度急剧下降而诱发痛风急性发作。②定期复查周围血象、肝功能等。 第二类是促进肾脏排泄尿酸药。主要用于无明显肾功能损害、60岁以下的痛风或高尿酸血症病人，尤适用于痛风结节较多者。用药后尿液酸碱度(pH值)迅速下降者要大量饮水并同服碱性药，以减少尿酸盐在肾脏沉积，防止结石形成。常用的促肾排尿酸药有苯溴马隆(痛风利仙)、丙磺舒(羧苯磺胺)，属磺胺类药，对磺胺过敏者禁用，长期应用要定期查全血细胞，防止骨髓抑制现象发生。磺吡酮(苯磺唑酮)，可作为磺胺过敏者丙磺舒的替代物。 适用于尿酸排泄低下型高尿酸血症，如果肾功能有轻度损害也可应用，有时在促进尿酸排泄增多后，肾功能也可得到改善。该类药物主要通过抑制近端肾小管对尿酸的重吸收而促进尿酸的排泄。 药物和用法： (1)丙磺舒(羧苯磺胺)：是一种有效的尿酸排泄促进剂,每天1克可使肾对尿酸的排泄平均增加50％，血尿酸平均下降30％。开始时每次0.25克，每日2次，2周内递增至每次O.5克，每日2～3次，如果血尿酸明显高于正常，可每1～2周再增加0.5克，直至血尿酸降至正常水平。每日最大剂量2克以下。高尿酸血症控制后可再逐渐减量维持。约5％患者有皮疹、发热、胃肠刺激、肾绞痛及激发急性痛风发作等副作用。

血红蛋白在纳米金修饰电极上的电化学研究(1)

第20卷第7期2008年7月化学研究与应用 Che m ical Research and App licati on Vol .20,No .7 July,2008 　 收稿日期:2007208209;修回日期:2008203209 基金项目:国家自然科学基金项目(20375008,20475001)资助;广东省科技攻关项目(2004B33301024,2005B10301041,2006B12401011)资 助;广东省自然科学基金项目(06108856)资助 联系人简介:程发良(19672),男,教授,主要从事生物电化学研究。Email:chengfl@dgut .edu .cn 文章编号:100421656(2008)0720872204 血红蛋白在纳米金修饰电极上的电化学研究 张　敏1 ,程发良 13 ,蔡志泉2,姚海军 1 (1.东莞理工学院生物传感器研究中心,广东　东莞　523106) (2.东莞理工学院城市学院,广东　东莞　523106) 关键词:纳米金;牛血红蛋白;化学修饰电极 中图分类号:O65711 文献标识码:A 氧化还原蛋白在电极上的直接电化学研究不但能获得有关蛋白质和酶的热力学和动力学性质等重要信息,为开发新型生物传感器和生物反应器提供理论指导,而且对了解它们在生命体内的电子转移机理和生理作用机制具有重要意义。 血红蛋白(Hb )是以血红素为辅基的蛋白质,在生物体中的主要功能是运输O 2。由于它的三维结构已经确定,所以常常用作研究蛋白质的结构 与功能关系的模型物[1,2] 。HB 分子庞大,电活性中心血红素被四条肽链包围而不易暴露,且在常规电极上强烈吸附和变性,使得它在一般固体电 极上的电子传递困难,需要借助媒介体[3] 、促进剂[4]或特殊电极材料[5] 促进电化学反应。 金属纳米粒子由于具有与其颗粒大小相关的 特殊性质[6] ,如表面效应、体积效应、量子尺寸效应等,从而产生不同于相应块体材料的电学、光学、磁学和催化性能,逐渐为电分析化学领域广泛 关注[7] 。文献曾报道了纳米金用于测定儿茶酚[8]、去甲肾上腺素[9]、葡萄糖[10211]等物质。本文利用电化学沉积法制备了纳米金修饰电极,利用该修饰电极测定了血红蛋白,实验结果表明:纳米 金具有良好的生物共容性[12] ,且纳米金较大的比表面积增强了血红蛋白在电极表面的吸附,显著提高了血红蛋白的电化学响应,实现了血红蛋白的直接电化学。 1　实验部分 111　试剂和仪器 牛血红白蛋白(国产,储备液在4℃条件下保存);氯金酸(HAuCl 4?3H 2O );实验用缓冲溶液为012mol/L Na Ac -HAc,pH 值采用混合不同比例的Na Ac 和HAc 溶液调整;实验所需的其余试剂均为分析纯;实验用水为二次蒸馏水;所有实验均在室温下进行。 P ARST AT2273电化学综合测试系统;电化学实验采用三电极体系:工作电极为裸玻碳电极(GCE )或者纳米金修饰电极(NG/GCE ),参比电极为饱和甘汞电极,对电极为铂电极;赛多利斯电子天平BS124S (北京赛多利斯仪器有限公司);超声波清洗器(昆山市超声波仪器厂);电子pH 计H I 98101(北京哈纳科仪科技有限公司)。112　修饰电极的制备金溶胶的制备参照文献[13] 。将玻碳电极先用金相砂纸抛光,然后依次用110、013μm 的A l 2O 3在麂皮上抛光至镜面,再移入超声水浴中清洗,最后依次用1∶1乙醇、1∶1HNO 3和蒸馏水超声清洗。把经过预处理的玻碳电极,用氮气吹干,置于金溶胶中于+115V 下电沉积2h 即可,标记为NG/GCE ,置于NaHc -HAc 缓冲溶液中备用。113　实验方法 电化学实验均在50mL 电解池中进行,用上述三电极系统,测定电化学曲线。测试前需向溶液中通氮气20m in 以上,以除去溶液中的溶解氧。所有实验均在室温下进行(约25℃)。

纳米材料修饰电极

A highly sensitive hydrogen peroxide amperometric sensor based onMnO2-modi?ed vertically aligned multiwalled carbon nanotubes，Analytica Chimica Acta，2010 MnO2-多臂碳纳米管 Cu电极 Gold nanoparticles mediate the assembly of manganese dioxide nanoparticles for H2O2 amperometric sensing，Electrochimica Acta，2010 MnO2–AuNP/ GCE H2O2电流传感 器 A novel nonenzymatic hydrogen peroxide sensor based on MnO2/graphene oxide Nanocomposite，Talanta，2010 GO/MnO2/ GCE（氧化 石墨烯） H2O2电流传感 器 Electrochemical investigation of MnO2 electrode material for supercapacitors，ScienceDirect，2011 MnO2泡沫镍电极MnO2电活性物 质作为超级电容 材料 Facile synthesis of novel MnO2 hierarchical nanostructures and their application to nitrite sensing，Sensors and Actuators B: Chemical，2009 MnO2/QPVP-Os/GCE (联吡啶锇取代的聚乙 烯吡啶) 亚硝酸盐传感器 Preparation of MnO2/graphene composite as electrode material for supercapacitors，J Mater Sci ，2011 MnO2/grapheme(石墨 烯) 超级电容器 Hydrogen peroxide sensor based on glassy carbon electrode modified with β-manganese dioxide nanorods，Microchim Acta (2011) β-MnO nanorods/GCE 。 H2O2电化学传 感器 Mn3O4 Graphene Hybrid as a High-Capacity Anode Material for Lithium Ion Batteries，American Chemical Societ，2010 Mn3O4/RGO（还原石墨 电极） 锂离子电池阳极 材料 Non-enzymatic electrochemical CuO nano?owers sensor for hydrogen peroxide detection，Talanta，2010 CuO/Cu箔H2O2电流传感 器（无酶） Synthesis of CuO nanostructures and their application for nonenzymatic glucose sensing，Sensors and Actuators B: Chemical，2010 CuO以碳为基底做成电 极 葡萄糖传感器 （无酶） A highly sensitive nonenzymatic glucose sensor based on CuO nanoparticles-modi?ed carbon nanotube electrode，Biosensors and Bioelectronics，2010 CuO/MWCNTs/Cu电极葡萄糖传感器 （无酶） An improved sensitivity nonenzymatic glucose biosensor based on a CuxO modi?ed electrode，Biosensors and Bioelectronics，2010 CuxO/Cu箔葡萄糖传感器 （无酶） Synthesis of CuO nanoflower and its application as a H2O2 sensor，Bull. Mater. Sci，2010 CuO NFS/Nafion-Au电 极 H2O2电流传感 器（无酶）

治疗痛风降尿酸的方法

治疗痛风降尿酸的方法 不知道大家对于痛风降尿酸的内容了解多少，现如今，随着社会生活的快速发展，人们在享受高质量现代化生活的同时，也出现了各种各样的疾病，痛风和尿酸过多就是其中的一种，需要我们尽快的解决出现的尿酸多的情况，可能我们大家对于治疗痛风降尿酸的方法还没有一个清晰的认识，下面就让我们一起来了解一下治疗痛风降尿酸的方法。 1、多喝水，每日保持1500～3000毫升，少量多次喝完，以助尿酸排出。

2、严格戒酒，啤酒加海鲜绝对禁止。大量摄入蛋白质会使我们人体处于一种微酸的环境，这样会促进尿酸结晶的形成;再喝酒影响排泄。 3、避免大量进食高嘌呤食物，像花生，牛肉，猪肉，海鲜，如动物的内脏、沙丁鱼、金枪鱼，豆类及发酵食物等;鱼虾类、鲜肉、豌豆、菠菜、酒等!避免吃炖肉或卤肉。 4、每天饮食中蛋白质的量应控制在每公斤体重1克左右，蛋白质以牛奶、鸡蛋为主。 5、饮食中蔬菜水果牛奶不限量，少吃盐，每天应该限制在2克至5克以内。

6、药物治疗，可降低血尿酸水平，减少痛风的急性发作，防止痛风石的形成，减轻肾脏损害。 7、每天饮食中蛋白质的量应控制在每公斤体重1克左右，动物内脏心、肝、肠、肾、脑和肉汤等以及沙丁鱼、虾、贝等海鲜都应少吃。饮食中蔬菜水果牛奶不限量，少吃盐，每天应该限制在2克至5克以内。每日的饮食结构中，以碳水化合物为主，碳水化合物可促进尿酸排出，可选用精白米、富强粉、玉米、馒头、面条等。避免过度劳累、紧张、受寒、关节损伤等诱发因素;

8、不宜使用抑制尿酸排出的药物 9、少吃脂肪，因脂肪可减少尿酸排出 以上内容为我们介绍了治疗痛风降尿酸的方法，这项内容对于我们是非常重要的，可以有效的帮助我们治愈出现的尿酸过多的情况，希望大家都能够减少痛风和尿酸过多给我们身体带来的影响，使我们都可以拥有一个健康的体魄。

纳米铂

纳米铂-L半胱氨酸修饰玻碳电极对 对苯二酚的检测研究 姓名：陈盼盼学号：201004034032 班级：化学一、文献综述 化学工业对人类社会和物质文明做出了重大贡献，人们在享受现代科学与技术给人们带来巨大的便利和快乐的同时，也逐渐意识到人类未来面临的巨大生存危机和困难。20世纪，人们逐步认识化学品的不当生产和使用会对人的健康、社区环境、生态环境产生危害性。据统计，世界每年生产的人工合成有毒化合物约50万种，共400万t，所有这些物质，近一半留在大气江河、湖、海内，另外每年还有将近18万t的铅和磷，3000万t的汞和各种有毒重金属流入水体内，200万t石油流进海洋。中国化学工业排放的废水、废气和固体废物分别占全国工业排放总量的22.5%、7.82%和5.93%，造成环境严重恶化，直接危害人类，又破坏生物圈，长期的影响着人类的生存。 对苯二酚,又名氢醌.化学名1,4-苯二酚，英文名 1,4-Dihydroxybenzene ; Hydroquinone。对苯二酚为白色针状结晶，分子式C6H4(OH)2，分子量110.11，比重1.332,熔点172℃，沸点286℃，闪点165℃，溶于水、乙醇及乙醚，微溶于苯。可燃。自燃点516℃。长期接触对二苯酚蒸气、粉尘或烟雾可刺激皮肤、粘膜，并引起眼的水晶体混浊。操作现场空气中最高容许浓度2mg/m3。 对苯二酚是一种重要的化工原料且应用广泛【1】主要用于显影剂、蒽醌染料、偶氮染料、合成氨助溶剂、橡胶防老剂、阻聚剂、涂料和

香精的稳定剂、抗氧剂等。对苯二酚因具有毒性，而且在自然条件下，不易降解，对人体环境有较大的危害, 因此受到人们的普遍关注，但其微量不容易不检测出来，因而需要更加灵敏的方法来检测目前，微量对二苯酚的测定方法有荧光谱法【2】、薄层色谱法【3】高效液相色谱法【4】动力学光度法【5】因为对苯二酚具有电学活性，可用电化学方法测定其含量，因此用选择性好、灵敏度有高的化学修饰电极测量对对苯二酚已有报道【6-7】，但是因为修饰过程复杂，干扰过多，灵敏度等问题。所以要设计更好的修饰方法来对微量对苯二酚的检测。 玻碳电极，是电化学研究中使用最为频繁的碳材料基础电极【8】。它的表面具有多变的性质，极易受实验条件的影响而发生变化。玻碳电极在应用与电化学研究时，在每次试验前需要对电极进行前处理，以改善其电化学相应信号的重现性【8】。目前，世界上几乎所有的实验室，对玻碳电极最为常采用的的前处理程序都是先在Al2O3磨料浆中打磨电极，随后在超声水浴中清洗。但这样的处理方法再重现性上不尽人意。因次，在这里我们要进行电化学活化以此来满足电分析实验室所需的各种高要求，各种有效的电化学活化方法均采用一个叫高阳极极化电位。电化学活化既可以在酸性、中性溶液中【9】也可以在碱性溶液中【10】，动力学研究表明活化电极的电子传导性质的改善可能以表面的亲水性【11】、清洁度【12】、含氧基团【13】等因素有关。 纳米材料具有表面效应【14】、体积效应【15】和介电限域效应登

电化学 纳米金修饰电极检测VC和尿酸

Published:April 02,2011 LETTER https://www.wendangku.net/doc/2611552954.html,/ac Electrochemical Sensing Using Quantum-Sized Gold Nanoparticles S.Senthil Kumar,Kyuju Kwak,and Dongil Lee* Department of Chemistry,Yonsei University,Seoul 120-749,Korea b Supporting Information R ecent advances in the synthesis of ultrasmall gold nanoparticles protected with organothiolate (SR)have opened the possibility to synthesize stable,atomically monodisperse gold nanoparticles.1à4Au 25(SR)18,Au 38(SR)24,and Au 144(SR)60are the examples of the quantum-sized gold nanoparticles that exhibit discrete electronic states and quantum con ?nement e ?ects.5,6These nanoparticles have received considerable attention recently because of their unique size-dependent electrochemical,optical,and catalytic properties.1à9Much progress has been made toward understanding their structures and fundamental physical and chemical properties.For example,electrochemical and optical study of the Au 25nanoparticles has revealed that Au 25has the highest occupied molecular orbital (HOMO)àlowest unoccupied molecular orbital (LUMO)gap of ca.1.33eV,representing the molecule-like property.5However,the technological application of such nanoparticles is still scarce.7à9It will be of great interest to utilize these functional materials in technolog-ical areas such as nanoelectronics,optoelectronics,and sensors since these nanoparticles could exhibit unique properties that di ?er sub-stantially from the corresponding atoms and bulk materials.Herein,we report the ?rst utilization of the quantum-sized Au 25nanoparticles in electrocatalysis and electrochemical sensing. The sol àgel technique has been used to immobilize gold nanoparticles to form a modi ?ed electrode.10à12Gold nanoparticles employed for electrochemical sensing thus far were,however,redox inactive nanoparticles with core diameters usually larger than 3nm and,thus,they were entrapped into the sol àgel network along with redox mediators or redox enzymes.10à12The sol àgel matrix provides stability to the redox mediator or the enzyme that interacts selectively with the target analyte,and the gold nanoparticles act as tiny con-ductors.In the present study,the unique electrochemical properties of Au 25nanoparticles o ?er particular virtues for the development of the modi ?ed electrode in which Au 25can serve as an electronic conductor as well as a redox mediator.Highly monodisperse,hexanethiolate-pro-tected Au 25nanoparticles (Au 25)were synthesized and characterized as [Au 25(SC 6H 13)18]à(see Supporting Information for experimental details).Au 25nanoparticles were entrapped into the sol àgel network by the hydrolysis of ethyltrimethoxy silane according to a literature procedure 13with slight modi ?cation.In a typical procedure,Au 25solution (10mg in 0.2mL of CH 2Cl 2)was mixed with 0.1mL of water containing 25%(v/v)glutaraldehyde and 0.2mL of ethyltri-methoxy silane,and the mixture was sonicated for 30min.The resulting homogeneous solution was subsequently stored at room temperature for 2h.10μL of this mixture was then dropcast on the surface of a glassy carbon electrode (GCE,3mm diameter)and allowed to dry overnight at room temperature to form the modi ?ed sol àgel electrode (Au 25SGE).The Au 25SGE was then washed thoroughly with water and used as a working electrode.Scheme 1depicts the cartoon of Au 25SGE 14with the Au 25entrapped in the sol àgel network. The square wave voltammogram (SWV)of Au 25in CH 2Cl 2shown in Figure 1A displays the redox characteristics of Au 25;three sets of well-de ?ned redox peaks with formal potentials at 0.62,0.31,and à1.33V vs Ag wire quasi-reference electrode (AgQRE)can be assigned to Au 251t/0,Au 250/1àand Au 251à/2àredox couples,respectively.1Cyclic voltammogram (CV)of the Au 25SGE in 0.1M KCl (Figure 1B)also shows well-de ?ned and reversible redox peaks with formal potential at 0.34V vs Ag/AgCl corresponding to Au 250/1àcouple.The redox peaks of Au 251t/0couple are not well-resolved,and they appear as a small shoulder around 0.43V.The reason for this behavior is unclear at this time.It could re ?ect the fact that small peak spacings between Au 251t/0and Au 250/1àcouples are expected when the dielectric constant of the medium is higher.5It could also be due to the fact that limited charge-compensating counterions are available in the sol àgel network for Au 251t/0upon the ?rst oxidation (Au 250/1à)reaction,as has been observed in the voltammogram of a Langmuir monolayer of similar particles.15The ?rst oxidation (Au 250/1à)appears,however,to be very stable and reproducible;the peak potentials and peak currents of the Au 25SGE Received:February 14,2011Accepted:April 2,2011ABSTRACT:This paper describes the electrocatalytic activity of quantum-sized thiolate protected Au 25nanoparticles and their use in electrochemical sensing.The Au 25?lm modi ?ed electrode exhibited excellent mediated electrocatalytic activity that was utilized for amperometric sensing of biologically relevant ana-lytes,namely,ascorbic acid and uric acid.The electron transfer dynamics in the Au 25?lm was examined as a function of Au 25concentration,which manifested the dual role of Au 25as an electronic conductor as well as a redox mediator.The electron transfer study has further revealed the correlation between the electronic conductivity of the Au 25?lm and the sensing sensitivity.

电沉积纳米金的读书笔记

[1]吉玉兰, 王广凤, 方宾. 纳米金/单壁碳管修饰玻碳电极对黄芩苷的电催化作用及快速检 测[J].2010, 6(6): 11-12. NG/GCE电极的制备 将l mg酸化的SWNT分散在5 mL DMF中，超声振荡至溶液均一。玻碳电极先在0.05 μm A2O3上抛光，然后分别在无水乙醇和二次蒸馏水中各超声清洗l min，晾干后，用微量进样器取10.0μL上述SWNT分散液滴加在玻碳电极表面，晾干，即得SWNT/GCE。将SWNT/GCE用二次水冲净置于0.1 mg/mL HAuCl4中，以扫速50 mV/s，于1.2～-0.6 V范围连续扫描5圈，取出用水反复冲净，晾干得NG／SWNT／GCE。 [2]张英，袁若，柴雅琴等. 纳米金修饰玻碳电极测定对苯二酚[J]. 西南师范大学学报, 2002, 6(31):87-90. NG/GCE电极的制备 将玻碳电极分别用0.1 μm和0.03 μm A12O3。粉末抛光成镜面，二次水冲洗，依次用(1+1) HNO3，无水乙醇和二次水超声清洗5 min，取出后用二次水冲净置于1 mg/mL HAuCl4中，以饱和甘汞电极(SCE)为参比，铂丝为对电极，于-0.2 V下保持60 s，取出后用二次水反复冲洗，得NG／GCE修饰电极，悬在pH为7.0的PBS上方保存备用。 NG/GCE修饰电极的性能 图1(a)是裸GCE和NG/GCE修饰电极在 5.0 mmol/L Fe(CN)63-/4- + 0.1 mol/L PBS(pH=7.0)中的循环伏安图．从图中可以看出，Fe(CN)63-/4-在NG/GCE修饰电极上峰电流明显增加，并且氧化还原峰电位差值减小，这主要是因为：NG使GCE电极的表面粗糙度和有效面积增加以及带正电荷的NG叫同带负电荷Fe(CN)63-/4-有较强的静电作用，使氧化还原发应更容易发生．图l(b)是裸GCE和NG/GCE修饰电极在5.0 mmol/L Fe(CN)63-/4-+0.1 mol/L PBS(pH=7.0)中的交流阻抗图，由图可知，NG/GCE电极膜的阻抗比裸GCE小很多，这说明NG能很好地增强电子的传输． [3]朱强，袁若，柴雅琴等.以纳米金为介质的无标记电流型甲胎蛋白免疫传感器的研 究[J]. 西南师范大学学报, 2002, 2(32):82-90.

葡萄糖氧化酶-金纳米粒子修饰电极灵敏检测葡萄糖浓度

葡萄糖氧化酶-金纳米粒子修饰电极灵敏检测葡萄糖浓度2016-06-19 12:24来源：内江洛伯尔材料科技有限公司作者：研发部 自组装法制备GOD/AuNPs/Chit-GP/GC 修饰电极过程示意图 近年来, 氧化还原酶与电极间的直接电子传输的相关研究引起了越来越多研究者的关注. 该领域的研究不但可以为深入探究生物体系复杂的电子传输机理提供良好的模型, 还可为新型的电化学生物传感器,生物燃料电池以及酶反应器等诸多方面的研究奠定基础. 然而, 由于酶的氧化还原中心往往深埋于其结构内部, 而且酶在裸电极表面容易因吸附而失活, 因此酶的活性中心与电极表面间的直接电子转移难以实现. 近期的研究发现, 选择合适的生物相容性材料和适宜的酶固载方法不仅可以有效保持酶的生物活性,还可较好地实现酶与电极间的直接电子传输. 由于其独特的结构和性质, 纳米材料尤其是碳基的纳米材料, 已被广泛应用到了酶的固载及新型生物传感器的构筑等方面. 例如, Sun等利用壳聚糖功能化石墨烯与葡萄糖氧化酶(GOD)间的自组装制备了GP-GOD玻碳(GC)修饰电极, 并利用其实现了对葡萄糖高效、灵敏的检测. Jiang等利用非共价修饰方法将壳聚糖修饰于单壁碳纳米管(SWNT)表面, 并进一步在复合物表面原位生长Au纳米粒子(GNPs), 从而制备了 SWNT-GNPs复合物. 利用该复合物与微过氧化物酶-11(MP-11)所构筑的 MP-11/SWNT-GNPs/Au修饰电极, 不仅可有效促进固载酶在电极表面的直接电子传输, 还可实现其对氧气的有效电催化. 作为一种新型碳基二维纳米材料,石墨烯由于具有较大的比表面积和良好的电子传输性等优点在电化学领域受到了广泛的关注. 研究表明, 利用石墨烯作为电极材料不仅可以促进氧化还原酶与电极间的直接电子转移, 还可以使所构筑的电化学生物传感器具有较好的性能. 例如, Zhao等将细胞色素c吸附到壳聚糖-石墨烯膜修饰的GC电极上成功构建了化学修饰电极. 该修饰电极不仅可实现细胞色素c与电极间的直接电子转移, 还可对NO表现出较好的电催化能力.然而, 由于石墨烯纳米片间存在强烈的范德华力及π-π相互作用, 致使其易发生团聚, 甚至堆叠成石墨, 从而使石墨烯丧失其特有的单片结构具有的独特性质, 也减少了其比表面积. 此外, 石墨烯表面的疏水性还阻碍了石墨烯与水溶性的氧化还原酶的进一步作用, 限制了石墨烯在生物传感器方面的应用. 因此, 制备兼具水溶性和生物相容性的石墨烯复合材料, 对其在氧化还原酶的固载及在第三代生物传感器构筑中的应用甚为重要.

同时检测多巴胺,抗坏血酸和尿酸的石墨烯-贵金属纳米复合物基电化学传感器

工程技术理论前沿2017年3月第29卷·307· 同时检测多巴胺，抗坏血酸和尿酸的石墨烯/贵金属纳米复合物基电化学传感器 徐小萌任俊鹏陆婉婷王成鑫王欢（指导老师） 吉林建筑大学材料科学与工程学院，吉林长春 130118 摘要：抗坏血酸（AA），多巴胺（DA）和尿酸（UA）是人类代谢过程中的重要化合物，是目前生物学和化学的研究热点之一。AA，DA和UA含量的变化与人体的健康密切相关，当浓度偏离正常水平时导致一些疾病的发生，如帕金森症、精神分裂症、癫痫、亨廷顿氏舞蹈症、抑郁症、通风等。最近，电化学传感器由于其良好的敏感性、选择性、分析周期短等特点，已经被广泛地应用到检测AA、DA和UA的含量当中。但是空白电极上AA、DA和UA的氧化峰重叠导致三者的区分困难，而无法检测。 [1]。 关键词：石墨烯；抗坏血酸；贵金属纳米复合物 中图分类号：TP212 文献标识码：A 文章编号：1671-5586（2017）29-0307-01 迄今为止，大量的纳米催化材料用于修饰电极制备同时检测AA、DA和UA的电化学传感器，主要包括金属纳米材料、碳基材料、聚合物等[2]。贵金属纳米传感器表现出优异的催化活性、稳定性好，但目前面临的问题是纳米尺寸的贵金属粒子在表面活性剂修饰时在化学势的作用下，会发生团聚，电化学活性的表面积会降低，传感器的灵敏度也会下降。近年来，一些科研工作者将铂、金、钯等金属纳米粒子组装到碳基纳米材料上特别是石墨烯材料，不仅防止了金属纳米粒子之间的聚集，而且极大地增加了复合材料电活性的比表面积、降低了成本，且两者之间的协同作用和电子的转移，使得石墨烯/贵金属纳米复合物用于各种传感器中并取得不错的结果。 1 石墨烯/Au纳米粒子复合物传感器 迄今为止，很多的Au纳米粒子复合物广泛作为电极材料，用于同时检测AA，DA和UA，主要有石墨烯/ Au纳米复合材料、石墨烯/Fe3O4 @ Au复合材料、碳纳米管/ Au纳米复合材料和Au @ MoS2 核壳材料。其中石墨烯/Au纳米复合材料，由于其独特的电子和催化性能，比单体材料更大的表面和更好的协同作用，得到了极大的关注。Yan等人[3]利用简单的液相还原法制备了三维石墨烯凝胶/金纳米复合材料，并制作了同时检测AA、DA和UA的电化学传感器。在最佳条件下，3DGH/AuNPs/GCE对AA，DA和UA的线性响应分别为1.0-700，0.2-30，1-60 μM，计算检测限为28 nM（AA），2.6 nM（DA）和5nM（UA），并且一些通常共存的物质（如赖氨酸，甘氨酸，葡萄糖，柠檬酸等）对传感器的干扰几乎可以忽略不计，选择性较好。 2 石墨烯/Pt纳米粒子复合物传感器 Pt基纳米催化剂的成本较高，且纳米尺寸下催化剂易聚集，基于此制备石墨烯/Pt纳米复合催化剂用于电催化是一种不错的选择。Li等人[4]利用一步反应制备了石墨烯/Pt复合物，研究了石墨烯/Pt纳米粒子复合物传感器对抗坏血酸和多巴胺的电化学响应和催化行为，结果发现AA和DA氧化的两个峰值电位之间的差异超过200 mV，可以将AA和DA 完全区分开。同时利用传感器对含有AA和DA的尿液进行了检测，结果表明，石墨烯/Pt纳米粒子复合材料将可能应用于临床使用中的AA和DA的常规分析。 3 石墨烯/Pd纳米粒子复合物传感器 商业上催化电极材料一般是贵金属Pt基材料，但是由于其成本问题，制约了传感器的商业发展。一种方法是采用成本较低并且能替代Pt的金属，如Pd。然而，与铂相比，钯具有低得多的活性，需要研究一种改进的Pd基催化剂的设计。众多科学家为此做出了很多努力，一般通过改变Pd的形貌、纳米结构、或者使用载体等手段提高催化剂的催化性能。例如，通过纳米Pd与石墨烯结合形成石墨烯/Pd催化剂，具有较高的电催化活性和稳定性。Wang等人[5]基于石墨烯/立方体Pd纳米复合材料修饰玻璃碳电极制作了DA和UA电化学传感器，利用循环伏安法和差分脉冲伏安法研究了电化学行为，发现新型石墨烯/立方体Pd纳米复合物传感器表现出良好的灵敏度，优异的选择性和出色的稳定性。石墨烯/双金属纳米粒子复合物传感器。 4 石墨烯/双金属纳米复合物传感器 与单金属纳米颗粒相比，双金属纳米粒子可以保留各组分的功能特性，并通过相互协同效应，增加表面积，增强电催化能力，促进电子转移和提高生物相容性。基于不同的合成策略，研究者制备了各种形貌结构如中空，异质，核壳，合金和孔隙的双金属纳米晶体。近年来报道了石墨烯/双金属纳米粒子复合材料，在电分析和电催化中表现出良好的电化学性能。Yan等人[6]通过一步还原乙二醇溶液合成石墨烯/Pd-Pt纳米复合材料，制备了电化学传感器，同时测定AA，DA和UA，并应用于人尿和血清样品中AA，DA和UA的检测，表现出比单一组分更高的催化活性。 5 结语 石墨烯/贵金属纳米复合物电化学传感器展现出较大的比表面积、较高的催化活性、较好的稳定性，并解决了催化剂成本偏高问题，在同时检测AA、DA和UA领域具有巨大的应用前景。 参考文献 [1]Ramesh P，Suresh G S，J.Electroanal.Chem，561，2004：173-180. [2]Bao Y，Song J，Mao Y，et al.Electroanalysis，2011，23（4）：878-884. [3]Zhu Q，Bao J，Huo D，et al.Sensors and Actuators B，2017，238：1316-1323. [4]Li F，Chai J，Yang H，et al.Talanta，2010，81（3）：1063-1068. [5]Wang J，Yang B，Zhong J，et al.Journal of Colloid and Interface Science，2017，497：172-180. [6]Yan J，Liu S，Zhang Z，et al.Colloids and Surfaces B：Biointerfaces，2013，111（1）：392- 397. 吉林省大学生创新创业项目（201610191016）资助 指导教师：王欢，吉林建筑大学材料科学与工程学院，讲师。