钾离子选择性液膜超微电极的研制

本文报道一个膜内阻很低的缬氨霉素钾离子选择性液膜微电极．当电极端径１μｍ和０．５μｍ时，电极内阻分别为１×１０１０Ω和７×１０１０Ω．该电极的选择性很好，允许钠和乙酰胆碱的干扰量分别可达５０００和３４００倍．在０．１４ｍｏｌ／Ｌ和０．５ｍｏｌ／ＬＮａ＋存在下，检测极限分别为１．６×１０－５ｍｏｌ／Ｌ和２．５×１０－５ｍｏｌ／Ｌ．     

新型全固态铁离子敏感电极研究

采用稀土电极材料六硼化镧制备了一种新的全固态铁离子敏感电极。研究了该敏感电极在常见介质中对Ｆｅ３＋的响应行为。结果表明，该铁离子敏感电极在１．５ｍｏｌ／ＬＨ３ＰＯ４介质中的线性响应范围、检测下限和响应斜率分别为１．０×１０－５～１．０×１０－１ｍｏｌ／ＬＦｅ３＋，６．０×１０－６ｍｏｌ／ＬＦｅ３＋和６０ｍＶ／ｐＣ，且具有较好的选择性。     

双酶电极测定血清中的葡萄糖的研究

本文将葡萄糖氧化酶和过氧化物酶固定在玻碳电极上，制成双酶生物传感器。用该生物传感器测定人体血清中的葡萄糖，尿酸、抗坏血酸、半胱氨酸和色氨酸等对测定无干扰。线性范围在５．０×１０－４～３．５×１０－６ｍｏｌ／Ｌ之间，检测限为５．０×１０－７ｍｏｌ／Ｌ，响应时间为２０ｓ。该生物传感器具有选择性和重现性好，灵敏度高，响应时间短等优点。     

石英谐振式NH_3敏元件

以在ＡＴ切型，Ａｕ做电极的石英振子上涂覆适当厚度的Ｌ（＋）抗坏血酸为敏感膜，制作气敏元件．实验表明，该元件对微量ＮＨ３（＜３．３×１０－６ｍｏｌ／Ｌ）具有很高的频率响应和灵敏度；对８．２×１０－５ｍｏｌ／Ｌ的Ｈ２，ＣＯ，ＣＨ４，Ｃ４Ｈ１０及８．２×１０－７ｍｏｌ／ＬＨ２Ｓ感度很低，有良好的选择性．     

电位溶出分析法同时测定罐头食品中痕量铅锡

利用不除氧电位溶出分析法成功地测定了溶出电位相近的Ｐｂ、Ｓｎ两元素。以０．０５ｍｏｌ／Ｌ草酸为介质，调节溶液ＰＨ＝１．０，以溶解氧做氧化剂，静止溶出，两元素均有分高清晰的平台出现。Ｐｂ、Ｓｎ的线性范围分别为：２．０×１０－９～２．０×１０－７ｍｏｌ／Ｌ和２．０×１０－８～２．０×１０－６ｍｏｌ／Ｌ。当富集时间为４ｍｉｎ时，Ｐｂ、Ｓｎ的检测限分别为５．０×１０－１０ｍｏｌ／Ｌ和５．０×１０－９ｍｏｌ／Ｌ。此法已成功地应用于测定罐头食品中的痕量Ｐｂ、Ｓｎ。     

利用选择性重原子增强的固体表面发光技术同时测定痕？…

利用ＳｒＣｌ２和Ｐｂ（Ａｃ）２作为选择性重原子微扰剂，分别诱导出吡哌酸的固体表面延迟荧光和氟哌酸的室温磷光，不经分离直接测定混合样品中的两种药物获得成功。在ｐＨ约１１的条件下测定吡哌酸的线性范围为５×１０＾－７ｍｏｌ／Ｌ￣３×１０＾－３ｍｏｌ／Ｌ，测定氟哌酸的线性范围为３×１０＾－５ｍｏｌ／Ｌ￣３×１０＾－３ｍｏｌ／Ｌ。     

铟-桑色素体系吸附溶出伏安法研究

对Ｉｎ（Ⅲ）－桑色素（ｍｏｒｉｎ）配合物在悬汞电极上的吸附伏安特性作了研究,确定了电极过程。在ＣｌＣＨ２ＣＯＯＨ底液中,有桑色素存在下,用１．５次微分吸附伏安法测定铟,线性范围和检测下限分别为３．５×１０－１０～１．５×１０－７ｍｏｌ／Ｌ和５×１０－１１ｍｏｌ／Ｌ。用此法测定了氢氧化铝、银粉和铅粉样品中的痕量铟,结果满意。     

生物碱－半导体场效应传感器的研制及应用

研制了生物碱（秋水仙碱或毛果芸香碱）－半导体场效应传感器，并测得了器件的浓度线性范围：２．５０×１０－５～４．００×１０－３ｍｏｌ／Ｌ（秋水仙碱）；９．９０×１０－５～５．０５×１０－３ｍｏｌ／Ｌ（毛果芸香碱）．该传感器可应用于药物制剂中秋水仙碱的测定．方法简便，效果良好．     

生物碱—半导体场效应传感器的研制及应用

研制了生物碱（秋水仙碱或毛果芸香碱）－半导体场效应传感器，并测得了器件的浓度线性范围：２．５０×１０＾－＾５－４．００×１０＾－＾３ｍｏｌ／Ｌ（秋水仙碱）；９．９０×１０＾－＾５－５．０５×１０＾－＾３ｍｏｌ／Ｌ（毛果芸香碱）。该传感器可应用于药物制章占秋水仙碱的测定，方法简便，效果良好。     

铟(Ⅲ)-芦丁体系的电化学吸附伏安法

对铟（Ⅲ）－芦丁络合物在悬汞电极上的吸附伏安法作了研究．在 ＨＡｃ－ＮａＡｃ缓冲溶液中,用单扫吸附伏安法可获得高灵敏度的铟（Ⅲ）－芦丁络合物的吸附还原峰．用１．５阶微分吸附伏安法测定铟,检测下限达５×１０－１１ｍｏｌ／Ｌ,线性范围是１×１０－１０～１×１０－７ｍｏｌ／Ｌ．用此法成功地测定了粮食中的痕量铟,并确定了电极过程．     

Electrocatalytic oxidation of H<Subscript>2</Subscript>O<Subscript>2</Subscript> at a carbon paste electrode modified with a nickel (II)-5, 11, 17, 23-tetra-tert-butyl-25, 27-bis(Diethylcarbamoylmethoxy) calix[4] arene complex and its application

Electrochemical behavior of a carbon paste electrode (CPE) modified with nickel(II)-5, 11, 17, 23-tetra-tert-butyl-25, 27-bis(diethylcarbamoylmethoxy) calix[4]arene (Ni (II)-L) complex and its electrocatalytic activity towards the oxidation of hydrogen peroxide were investigated by cyclic voltammetric technique in a 5.0×10⁻² mol/L NaClO₄+1.0×10⁻³ mol/L NaOH solution. It was found that Ni(II)-L acts as an effective catalyst for the oxidation of hydrogen peroxide. The modified electrode exhibited a linear response over a hydrogen peroxide concentrations in the range of 2.0×10⁻⁵−1.0×10⁻⁴ mol/L with a detection limit as low as 1.0×10⁻⁶ mol/L. The relative standard deviation was 3.5% for 5 successive determinations of H₂O₂ at 1.0×10⁻⁵ mol/L. The modified electrode was used successfully in rainwater analysis. Foundation item: Supported by the Natural Science Foundation of Hubei Province (98J040). Biography: Li Chun ya(1972-), Ph. D. candidate, research direction: electroanalysis and electrosynthesis.     

化学修饰电极对乙基麦芽酚的测定

通过循环伏安法将氧化石墨烯和L-谷氨酸混合液修饰在玻碳电极表面,制备了聚L-谷氨酸/石墨烯修饰电极。通过循环伏安法及差分脉冲伏安法,研究乙基麦芽酚的电化学性质。实验结果表明:最佳条件下,乙基麦芽酚分别在0.951 V和0.852 V处出现氧化峰。其浓度分别在6.00×10-6～1.00×10-4 mol/L及4.00×10-6～4.00×10-4 mol/L范围内呈现良好的线性关系,检出限为4.0×10-7 mol/L。用于检测食品中的乙基麦芽酚,结果满意。     

循环伏安法对邻苯二酚的测定

将氧化石墨烯分散液及谷氨酸的混合液用循环伏安法修饰在玻碳电极上，制备出聚L-谷氨酸/石墨烯修饰电极。通过循环伏安法，对邻苯二酚在此修饰电极上的电化学行为进行研究。结果表明，在最佳优化的实验条件下，邻苯二酚在0.507 V处出现一对氧化还原峰，且浓度在2.00×10^-6mol/L~4.00×10^-4mol/L范围内表现出良好的线性关系，检出限为6.7×10^-7mol/L。利用该方法测定样品中的邻苯二酚，结果令人满意。     

Voltammetric Response of Epinephrine at Carbon Nanotube Modified Glassy Carbon Electrode and Activated Glassy Carbon Electrode

0Introduction Epinephrine(EP)isanimportantcate cholamineneurotransmitterinthemammaliancentralnervoussystem,whichissecretedbythesu prarenalglandalongwithnorepinephrine.Itisgen erallyusedtotreathypertension,bronchialasthma,organicheartdisease,andincardiacsurgeryand myocardialinfarction[1].VariousmethodshavebeendevelopedforEPstudy,suchascapillaryelectro phoresis(CE)[2],highperformanceliquidchroma tography(HPLC)andflowinjectionanalysis(FIA)[3].Numerousobservationsontheelectro chemicalbehavio…     

聚L-谷氨酸/石墨烯修饰电极对碘的测定

使用循环伏安法制备了聚L-谷氨酸/石墨烯修饰电极,应用扫描电镜和阻抗对修饰电极进行了表征,建立了示差脉冲伏安法测定碘的新方法。研究结果表明,在最佳实验条件下,使用示差脉冲伏安法(DPV)法测定碘,碘浓度在1.00×10-3～5.00×10-7 mol/L浓度范围内与峰电流呈现良好的线性关系,检出限为1.00×10-7 mol/L。该方法用于测定样品中的碘,结果令人满意。     

2,3-二巯基乙二酸自组装膜电极对多巴胺和尿酸的同时测定及其应用

利用电化学方法研究了2,3-二巯基乙二酸(DMSA)自组装膜的电化学行为,发现DMSA自组装膜对于多巴胺和尿酸的氧化能够起到明显的电催化作用.在优化条件下,多巴胺与尿酸的氧化峰电流分别与其浓度在1.0×10-4～1.0×10-3和8.0×10-4～9.0×10-3 mol/L内呈良好的线性关系,检出限分别为3.0 ×10-5和8.0×10-5 mol/L.该电极用于实际样品的测定,结果满意.     

Determination of isocarbophos by cathodically sweeping oscilliopolarography

Determination of isocarbophos by cathodically sweeping oscilliopolarography is described. In a 1.0×10⁻⁵ mol/L sodium dodecylbenzene sulfonate (SDS)+0.1 mol/L HAC-NaAC (pH=4.0) buffer medium, isocarbophos and its alkaline hydrolysate exhibited sensitive second derivative wave at −0.50 V and −0.48 V respectively. The peak current was linearly proportional to the concentration of isocarbophos in the range of 5.40×10⁻⁶−1.05×10⁻⁴ mol/L by detecting isocarbophos directly. The detection limit was 3.60×10⁻⁶ mol/L with the relative standard derivation (RSD) of 7.3%. By employing an alkaline hydrolysis, the peak current was linearly proportional to the concentration of isocarbophos in the range from 7.70×10⁻⁷ mol/L to 1.24×10⁻⁴ mol/L, and the detection limit was 5.80×10⁻⁷ mol/L with RSD of 3.1%. The hydrolysis procedure and the electrode reaction were studied by voltammetry. Foundation item: Supported by the Foundation of Chinese-France Cooperation Program on Advanced Research Biography: ZHANG Wu-ming (1929-), female, Professor.     

Organic media enhanced spectrofluorimetric determination of L-ascorbic acid

A novel spectrofluorimetric method for the determination of L-ascorbic acid is proposed. It is based on the inhibition of L-ascorbic acid on the formation of 2,3-diaminophenazine, which is an oxidation product ofo-phenylenediamine catalyzed by laccase. The fluorescence (at λ_cx/λ_cm=464 nm /530 nnm) was enhanced strongly in the presence of organic media. The mechanism ofo-phenylenediamine oxidation reaction catalyzed by laccase in the presence of L-ascorbic acid is discussed. L-ascorbic acid is determined in the ethanol, 1,4-dioxane and acetone over the linear range of 4.0×10⁻⁷≈1.2×10⁻⁴ mol/L, 4.0×10⁻⁷≈8.0×10⁻⁵ mol/L and 4.0×10⁻⁷≈1.0×10⁻⁴ mol/L with a detection limit of 1.20×10⁻⁵ mol/L, 1.19×10⁻⁵ mol/L and 1.24×10⁻⁸ mol/L, respectively. The method has been successfully applied to the simple and rapid determination of L-ascorbic acid in pharmaceuticals and milk powder. Supported by National Natural Science Foundation of China and the Special Funds of State Education Committe for Doctorate Research Huang Zuyun: born in Aug. 1963. Ph.D     

石墨烯/聚苯胺复合膜修饰玻碳电极测定多巴胺

采用原位聚合法制备石墨烯/聚苯胺复合物,利用X射线衍射技术和红外光谱进行表征,通过滴涂法制备修饰电极,对多巴胺进行电化学测定。分别对支持电解质、pH值和扫描速率等实验条件进行了优化,建立了测定多巴胺的新方法。实验结果表明,经石墨烯/聚苯胺修饰后的玻碳电极对多巴胺具有很好的催化氧化作用。在0.1mol/L磷酸盐缓冲溶液中(pH值为4.0),多巴胺的线性响应范围为8.0×10-7~5.0×10-3 mol/L,相关系数为0.994,检出限为9.8×10-8 mol/L。该法用于实际样品中多巴胺的测定,回收率为97.1%~103.4%。     

Chemiluminescence determination of thiourea using tris (1,10-phenanthroline)-ruthenium (II) KMnO4 system

The light emission produced by thiourea in oxidation process by permanganate in acidic solution in the presence of Ru(phen) ₂ ^{3 +} is used to determine 1.0×10⁻⁵ −1.0×10⁻⁵ mol/L thiourea. The limit of detection is 9.8×10⁻⁹ mol/L and the relative standard deviation is 1.1% for a 1.0×10⁻⁵ mol/L thiourea solution (n=10). The method was applied satisfactorily to the determination of thiourea. Foundation item, Support by Ministry of Education, Wuhan University and Alumni Association of it Biography: Wu Feng-wu(1963-), Male, Ph. D, research direction: analytical chemistry.