硒半胱氨酸和硒胱氨酸的间接气相色谱测定──溴化氰－气相色谱法

将硒半胱氨酸（ＳｅＣｙｓＨ）甲基化，对硒胱氨酸（ＳｅＣｙｓ）需还原后再甲基化。它们生成的甲基硒半胱氨酸（ＣＨ＿３ＳｅＣｙｓＨ）能与溴化氰（ＣＮＢｒ）发生专一性反应，定量生成的硒氰酸甲酯（ＣＨ＿３ＳｅＮ）可用气相色谱法（ＧＣ）测定。此法简称ＣＮＢｒ－ＧＣ法，检测限４×１０￣（－８）克ＳｅＣｙｓ，准确度８９．５％，相对标准差１２．１％，非含硒氨基酸不干扰。此法适于样品中微量硒氨基酸（硒蛋氨酸ＳｅＭｅｔ，ＳｅＣｙｓＨ和Ｓｅｃｙｓ）的测定。     

硒半胱氨酸和硒胱氨酸的间接气相色谱测定──溴化氰－气相色谱法

 将硒半胱氨酸（ＳｅＣｙｓＨ）甲基化，对硒胱氨酸（ＳｅＣｙｓ）需还原后再甲基化。它们生成的甲基硒半胱氨酸（ＣＨ＿３ＳｅＣｙｓＨ）能与溴化氰（ＣＮＢｒ）发生专一性反应，定量生成的硒氰酸甲酯（ＣＨ＿３ＳｅＮ）可用气相色谱法（ＧＣ）测定。此法简称ＣＮＢｒ－ＧＣ法，检测限４×１０￣（－８）克ＳｅＣｙｓ，准确度８９．５％，相对标准差１２．１％，非含硒氨基酸不干扰。此法适于样品中微量硒氨基酸（硒蛋氨酸ＳｅＭｅｔ，ＳｅＣｙｓＨ和Ｓｅｃｙｓ）的测定。     

用流动注射法研究巯基化合物-铈(Ⅳ)-氢化可的松的化学发光反应

采用流动注射法研究了巯基化合物－铈（Ⅳ）－氢化可的松（ＨＣＲｓ）体系的化学发光行 为，对影响化学发光强度的诸因素进行试验和探讨，建立了流动注射化学发光法检测谷胱甘 肽（ＧＳＨ），半胱氨酸（Ｃｙｓ）等含巯基化合物的新方法。检测ＧＳＨ和Ｃｙｓ和线性范围分别为 ２．０×１０－６～１０．０×１０－５ｍｏｌ／Ｌ和１．０×１０－６ｍｏｌ／Ｌ～１０．０×１０－５ｍｏｌ／Ｌ；检测限分别为２．０ ×１０－７ｍｏｌ／Ｌ和１．４×１０－６ｍｏｌ／Ｌ（Ｓ／Ｎ＝３）；ＧＳＨ、Ｃｙｓ加入血清中进行回收测定的回收率 为９０％～９５％，相对标准偏差小于４％。     

用流动注射法研究巯基化合物—铈（IV）—氢化可的松的化学发光反应

采用流动注射法研究了巯基化合物－铈（Ⅳ）－氢化可的松（ＨＣＲｓ）体系的化学发光行为，对影响化学发光强度的诸因素进行试验和探讨，建立了流动注射化学发光法检测谷胱甘肽（ＧＳＨ），半胱氨酸（Ｃｙｓ）等含巯基化合物的新方法。检测ＧＳＨ和Ｃｙｓ和线性范围分别为２．０×１０＾－６￣１０．０×１０＾－５ｍｏｌ／Ｌ和１．０×１０＾－６ｍｏｌ／Ｌ￣１０．０×１０＾－５ｍｏｌ／Ｌ；检测限分别为２．０×１０＾－７ｍｏｌ     

Study on the Total Synthesis of Hainanolide－Construction of Tricyclic Intermediate（I）

ＳｔｕｄｙｏｎｔｈｅＴｏｔａｌＳｙｎｔｈｅｓｉｓｏｆＨａｉｎａｎｏｌｉｄｅ－ＣｏｎｓｔｒｕｃｔｉｏｎｏｆＴｒｉｃｙｃｌｉｃＩｎｔｅｒｍｅｄｉａｔｅ（Ｉ）ＬｕＹａｎＺＨＡＮＧ；ＳｈｉＺｈｉＣＨＥＮ；ＤｏｎｇＷＥＩ；ＬｉａｎｇＨＵＡＮＧ；ＪｉＪｉｅＣＨＡ...     

山梨醇催化加氢制丙二醇和乙二醇

山梨醇催化加氢制丙二醇和乙二醇Ｇ．Ｇｕｂｉｔｏｓａ和Ｂ．Ｃａｓａｌｅ用Ｒｕ／Ｓｎ催化剂完成了由山梨醇加氢变为丙二醇及乙二醇的过程。ＨＯＣＨ２（ＣＨ）４ＯＨＣＨ２ＯＨＨ２Ｒｕ－Ｓｎ→ＣＨ３ＣＨＣＨ２ＯＨＯＨ＋ＨＯＣＨ２ＣＨ２ＯＨ将山梨醇的碱性溶液（山梨...     

化合物Cs3Dy2Br9合成机理的相化学研究

研究了ＣｓＢｒ与ＤｙＢｒ３在氢溴酸介质中反应的四元体系ＣｓＢｒ－ＤｙＢｒ３－ＨＢｒ（１３％）－Ｈ２Ｏ（２５℃）相化学关系，发现了新物相５：３型化合物５ＣｓＢｒ．３ＤｙＢｒ．２４Ｈ２Ｏ，并对其进行了Ｘ射线，ＤＴＧ，ＤＴＡ及偏光显镜等方面的研究。     

Synthesis and Crystal Structure of Bis（tetra－hydrofurfurylcyclopentadienyl）ytterbium Chloride

ＳｙｎｔｈｅｓｉｓａｎｄＣｒｙｓｔａｌＳｔｒｕｃｔｕｒｅｏｆＢｉｓ（ｔｅｔｒａ－ｈｙｄｒｏｆｕｒｆｕｒｙｌｃｙｃｌｏｐｅｎｔａｄｉｅｎｙｌ）ｙｔｔｅｒｂｉｕｍＣｈｌｏｒｉｄｅＺＨＵＡＮＧＸｉｕ－ｌｉ;ＺＨＡＮＧＳｕｏ－ｂｏ;ＨＵＮｉｎｇ－ｈａｉａｎｄ...     

The Atomic Weight of Gadolinium, Dysprosium and Erbium

ＴｈｅＡｔｏｍｉｃＷｅｉｇｈｔｏｆＧａｄｏｌｉｎｉｕｍ，ＤｙｓｐｒｏｓｉｕｍａｎｄＥｒｂｉｕｍＴｓｉｎｇＬｉｅｎＣＨＡＮＧ（ＤｅｐａｒｔｍｅｎｔｏｆＣｈｅｍｉｓｔｒｙ，ＰｅｋｉｎｇＵｎｉｖｅｒｓｉｔｙ，Ｂｅｉｊｉｎｇ１００８７１）ＤｉｎｇＳｈｕｎＧＡ...     

毛细管气相色谱／原子吸收联用及大蒜油中痕量硒化学形态分析的研究

本文提出并建立了毛细管气相色谱／原子吸收联用（ＣＧＣ／ＡＡＳ）装置，并在此装置上建立了（ＣＨ３）２Ｓｅ、（ＣＨ３）２Ｓｅ２的分析方法。本方法的最小检测量分别为０．３ｎｇ和０．０４ｎｇ。回收率分别为９７％～１０５％和９３％～１１０％，已用于大蒜油的实际样品分析，取得了满意的结果。     

Liquid Chromatographic Determination of Glutathione with Electrochemically Pretreated Glassy Carbon Electrode

Abstract

Simple electrochemical pretreatment of a glassy carbon electrode used as a working electrode in an electrochemical detector has been found to enhance the analytical capability of the detector for the determination of glutathione by lowering the required operating potential as well as by increasing the maximum oxidation current. The electrochemical pretreatment of the electrode was made in a 0.2 M phosphate buffer (KH₂PO₄-KOH, pH 6.5) at +1.9 V vs. Ag/AgCl for 2 min. The minimum detectable quantity of glutathione was found to be about 100 pg, when eluate from a reversed-phase column was amperometrically monitored by aid of the detector with the electrochemically pretreated glassy carbon electrode. Amount of glutathione in a rat lens was determined by the chromatographic method developed in this study.     

金纳米粒子富集-高效液相色谱同时测定人血浆中三种氨基硫醇

建立了金纳米粒子富集-高效液相色谱-紫外检测(HPLC-UVD)同时测定人血浆中3种氨基硫醇(半胱氨酸(Cys)、高半胱氨酸(Hcys)、谷胱甘肽(GSH))的新方法。以Tween 20修饰的金纳米粒子作为选择探针萃取富集氨基硫醇。经二硫苏糖醇脱附后,采用SpursilTM C18柱(250 mm×4.6 mm, 5 μm)分离氨基硫醇,以60 mmol/L磷酸盐缓冲溶液(pH 2.0)等度洗脱,检测波长为200 nm。3种氨基硫醇的浓度分别在0.025～350 μmol/L、0.02～60 μmol/L、0.01～50 μmol/L内与峰面积具有良好的线性关系,相关系数均高于0.99。方法检出限(信噪比为3)分别为5.0、6.0和2.5 nmol/L,回收率为92.8%～106.0%。该方法能显著降低血浆样品中内源性物质的干扰,提高HPLC-UVD的选择性和灵敏度。将该方法应用于心血管病人血浆中上述氨基硫醇的分离测定,结果显示: 与对照组相比,疾病组血浆中的Hcys和GSH水平存在显著性差异,Cys不存在显著性差异。     

以3,4-二羟基肉桂酸为介质的多壁碳纳米管糊电极用于检测药物和尿液样品中的谷胱甘肽(英文)

A sensitive and selective electrochemical sensor for the determination of glutathione(GSH) was developed using a modified multiwall carbon nanotube paste electrode with 3,4 dihydroxy cinnamic acid as a mediator.This modified electrode showed very high electrocatalytic activity for the anodic oxidation of GSH.Under the optimized conditions,the electrocatalytic peak current showed a linear relationship with GSH concentration in the range of 0.5-400.0 μmol/L with a detection limit of 0.1 μmol/L GSH.The relative standard deviations for seven successive assays of 5.0 and 25.0 μmol/L GSH were 2.2% and 2.7%,respectively.The modified electrode was used for the determination of GSH compounds in real urine samples.     

Studies on the Voltammetric Behavior of Nicardipine Hydrochloride and its Voltammetric Determination at the Co/GC Modified Electrode

ＩｎｔｒｏｄｕｃｔｉｏｎＴｈｅｔｅｃｈｎｉｑｕｅｏｆｉｏｎｉｍｐｌａｎｔａｔｉｏｎｈａｓｂｅｅｎｄｅｖｅｌｏｐｅｄａｓａｍｅａｎｓｏｆｉｎｔｒｏｄｕｃｔｉｎｇｆｏｒｅｉｇｎａｔｏｍｓｉｎｔｏｔｈｅｓｕｒｆａｃｅｌａｙｅｒｓｏｆａｓｏｌｉｄ．Ｔｈｉｓｔ...     

微透析活体取样与高效液相色谱-电化学检测法联用测定帕金森大鼠脑中神经递质

建立了一种微透析活体取样与高效液相色谱-电化学检测法联用技术测定自由活动大鼠脑中7种单胺类神经递质的方法.高效液相色谱采用Aglient XDB-C18柱,流动相为pH 3.0的0.1 mol/L H3PO4-NaH2PO4缓冲液与甲醇的混合液(90:10,V/V),流速为0.3 mL/min,电化学检测的工作电极为玻...     

氧化石墨烯/铁氰化铈修饰玻碳电极同时测定扑热息痛和咖啡因

采用滴涂法和电沉积法制备了氧化石墨烯/铁氰化铈(CeFe(CN)6)纳米复合膜修饰玻碳电极。用扫描电镜对氧化石墨烯和氧化石墨烯/CeFe(CN)6纳米复合膜进行了表征。分别用循环伏安法和差分脉冲伏安法研究了扑热息痛和咖啡因在修饰电极上的电化学行为。结果表明,在0.1 mol/L醋酸盐缓冲溶液(pH5.0)中,扑热息痛和咖啡因在此修饰电极上具有良好的电化学行为,扑热息痛和咖啡因分别在1.0×10-7～6.0×10-5mol/L和1.0×10-6～1.3×10-4mol/L浓度范围内与电化学响应信号呈良好的线性关系,相关系数分别为0.990和0.992;信噪比为3时,扑热息痛和咖啡因检出限分别为5.0×10-8mol/L和5.2×10-7mol/L。将本方法用于人尿样品分析,回收率为96.1%～105.4%。     

Amperometric determination of glutathione and cysteine on a Pd-IrO(2) modified electrode with high performance liquid chromatography in rat brain microdialysate

A Pd/IrO(2) co-electrodeposited glassy carbon electrode was prepared and the electrochemical behavior of glutathione (GSH) at this chemically modified electrode (CME) has been studied by cyclic voltammetry (CV). The results indicated that the modified electrode efficiently exhibited electrocatalytic oxidation for GSH with relatively high sensitivity, stability, and long-life. Coupled with high-performance liquid chromatography (HPLC), the Pd/IrO(2) modified electrode was utilized for the electrochemical detection (ECD) of the thiocompounds, glutathione and cysteine (Cys). The peak currents were linear with the substance concentrations in the range of 1.0 x 10(-5) mol L(-1) to 8.0 x 10(-4) mol L(-1) for GSH and 4.0 x 10(-6) mol L(-1) to 2.0 x 10(-4) mol L(-1) for Cys. The detection limits were 2.0 x 10(-6) mol L(-1) for GSH and 5.0 x 10(-7) mol L(-1) for Cys with S/N of 3. The method has been successfully applied to assess the contents of GSH and Cys in rat brain microdialysates.     

HPLC／CoPC修饰电极安培检测大鼠心肌线粒体中谷胱甘肽的研究

研究了钴酞菁修饰电极的修饰方法及其电化学性质。它可以催化氧化谷胱甘肽,降低ＧＳＨ的过电位。以ＣｏＰＣ何尝修饰电极为工作电极的安培薄层化学检测器,与高压认相色谱联用,在工作电极电位为＋０．８Ｖ时,ＧＳＨ的浓度在３．０＊１０＾－６ｍｏｌ／Ｌ－１．０＊１０＾－３ｍｏｌ／Ｌ浓度范围内与峰电流呈良好的线性关系,线性相关系数为０．９９９１,检出限为１．０＊１０＾－３ｍｏｌ／Ｌ浓度范围内与峰电流呈良好的线性关系     

高效液相色谱-喷壁/薄层安培检测器用于同时测定5种环境优先污染酚

结合传统的喷壁式和薄层式安培检测器,制备了一种新型的喷壁/薄层安培检测器。 联合高效液相色谱（HPLC）同时对5种环境优先污染酚进行了检测。 实验发现,安培检测工作电极面积的增大会导致响应电流的增大,但同时也会增大噪声,因此,基于信噪比优化电极面积是重要的。 选用色谱柱SHIM-PACK VP-ODS（150 mm×4.6 mm）,流动相V（甲醇）∶V（0.1 mol/L PBS,pH=7.5）=40∶60,柱温40 ℃,流速1 mL/min,进样量20 μL,安培检测电位为1.0 V,紫外检测波长为220 nm,喷壁-薄层安培检测器不经富集对对硝基酚、苯酚、间甲酚、2,4-二氯苯酚和2,4,6-三氯苯酚共5种酚类物质的检测下限均低于1 μg/L(S/N=3),优于相同条件下的紫外检测器和商品电化学检测器。 用于实际水样分析亦获满意结果。     

Development and validation of a liquid chromatography/tandem mass spectrometry method for the quantification of flucloxacillin and cloxacillin in microdialysis samples

In the present study we developed and validated a liquid chromatography/tandem mass spectrometry (LC‐MS/MS) assay for the determination of flucloxacillin in human plasma and microdialysis samples and cloxacillin in microdialysis samples, using oxacillin as the internal standard for the assay. The samples were separated on a UPLC BEH C₁₈,1.7 µm column (2.1 × 50 mm) and analyzed by a tandem–quadrupole mass spectrometer in multiple reaction monitoring mode using an electronspray ionization interface. For flucloxacillin the method was demonstrated to be accurate and precise in the linearity range of 1–30 mg/L in plasma and 0.05–5.0 mg/L for microdialysate with a regression coefficient (r) of 0.9986 and 0.9989 in plasma and microdialysate respectively. For cloxacillin it was accurate and precise in the range of 0.1–5.0 mg/L for microdialysate with a regression coefficient of 0.9972. The method presents a high sensitivity for flucloxacillin (lower limit of quantification of 1 mg/L for plasma and 0.05 mg/L for microdialysis samples) combined with a low within‐ and between‐day variation (<5.0% for flucloxacillin and cloxacillin in microdialysis samples and <6.5% for plasma samples of flucloxacillin). The validation experiments for the microdialysis probes showed a relative recovery of 85.5% for flucloxacillin at a flow rate of 1.0 μL/min. The results justify the use of this assay for clinical studies for measuring free unbound tissue concentrations of flucloxacillin in patients with a Staphylococcus aureus bacteremia. Copyright © 2014 John Wiley & Sons, Ltd.