棒状薄层色谱法在药物分析中的应用

棒状薄层色谱法或称薄层棒色谱法(Thin-Layer Stick Chromatography)是薄层色谱与气相色谱检测手段联用的一种分析方法,即将展层后的薄层棒通过氢火焰,使组分电离后进行检测的方法。薄层色谱对多组分的分离具有较高效能,一般用薄层扫描仪籍样品组分对光的特征吸收进行检测,但对那些在可见与紫外波段无显著吸收的物质,则必须通过衍生化或显色手段方能测定。火焰离子化检测器(FID)对绝大多数有机物能产生较高响应,而且     

磺化双酞菁钴自组装膜结构的表面增强拉曼光谱

采用自组装的方法构建了双核磺化酞菁钴轴向配位有序排列的膜层结构. 结合双核磺化酞菁钴分子体系自身所具有的性质及其和桥联分子四巯基吡啶之间相互作用的信息, 对其自组装膜的表面增强拉曼光谱进行了分析, 探讨了其自组装行为, 合理地解释了本自组装体系的膜层结构. 研究结果表明, 双核磺化酞菁钴分子(Bi-CoPc)在这种自组装膜中是以与基底平面存在一定夹角的倾斜的方式排列的.     

关于棒状薄层色谱法的误差问题

1967年英国的Padley发明了棒状薄层色谱氢焰扫描法。用直径0.5mm,长度200mm的石英棒,表面涂一层吸附剂,代替一般的薄层色谱板,进行样品的展开分离,然后挥发掉溶剂,直接通过FID的火焰,进行扫描、检测和定量。扫描仪的原理如图1。后来日本的公司对该法进行了研究和改进,1973年生产出商品仪器Thin-     

薄层色谱法测定油脂加氢产物中含氧化合物

建立了用棒状薄层色谱-氢火焰离子化检测器结合红外光谱快速测定动植物油脂加氢产物中含氧化合物的方法。不需要衍生化处理,并且可以批量检测,结果的标准偏差为4.6%;样品上样量为0.1 mg时,检出限为323μg/g。方法可以同时兼顾常量分析和微量分析,用于动植物油脂加氢反应过程及终产物的快速高通量检测。     

轻质油品中硫醇的催化氧化脱除

二次加工得到的轻质油品常常由于含有较多硫醇而造成质量低下。Merox脱硫醇(即脱臭)法虽已成熟,但作为催化剂的磺化酞菁钴或聚酞菁钴,不仅合成与制备条件苛刻,而且其催化氧化活性对这些条件又十分敏感。本文考察了一组金属离子插入交换蒙脱石的催化氧化脱臭性能。结果表明,C_0~(2+)蒙脱石不仅制备简便,而且具有与磺化酞菁钴极相近的脱臭性能。     

薄层色谱分析法及其进展

介绍常规薄层色谱和几种高效薄层色谱分析方法,薄层色谱与红外光谱、表面增强拉曼光谱、核磁共振、质谱、电化学等联用检测技术,以及薄层色谱与联用检测技术在医药、生物制品、毒物、环境有害物质、食品及其他领域定性定量分析中的应用,并对其前景进行了展望。     

薄层色谱法分离四苯基卟啉和四苯基钴卟啉

提出了用薄层色谱分离四苯基卟啉和四苯基钴卟啉的方法.方法中以石油醚-二甲苯(体积比为2:1)二元溶剂体系为展开剂,在硅胶薄层板上分离了四苯基卟啉和四苯基钴卟啉,所得斑点清晰、无拖尾.应用此薄层色谱法跟踪检测了四苯基钴卟啉的合成.     

磺化酞菁与人血清白蛋白复合物的光动力活性研究

通过光谱法研究了三种磺化酞菁(α位四磺化酞菁、β位四磺化酞菁和α位单取代磺化酞菁)与人血清白蛋白(HSA)的相互作用.结果 表明,HSA对α位四磺化酞菁的存在状态(单体、聚集体)影响显著,而对β位四磺化酞菁和α位单取代磺化酞菁的存在状态没有明显影响.磺化酞菁与HSA均存在明显的相互作用,且.四磺化酞菁与HSA的结合作用...     

棒状薄层色谱/氢火焰检测法在石油重质油烃组成分析上的应用

在石油重质油的烃组成分析中,液固色谱,质谱和高效液相色谱等已被广泛采用。但是,这些方法均存在着一些缺点,如分析时间长、定量困难等。棒状薄层色谱/氢火焰检测(TLC/FID)法则较好地克服了上述缺点。本文扼要叙述了TLC/FID法的分析原理、试验技术和在石油重质油烃组成分析中的应用实例,并对该技术的发展前景提出了看法。     

薄层棒色谱法研究 (FID直接扫描色谱定量法)

一、序言目前国内薄层色谱的定量方法,一般仍用手工操作,手续繁杂,所需时间也较长,应尽快生产国外已广泛使用的薄层扫描仪。但国外常用的薄层扫描仪,是根据被测物质的光学性质进行检测的。其使用性能随被测物质而异,结构也比较复杂,不易制造。1967年Padley提出了薄层棒火焰离子化检测器(FID)扫描仪,用表面涂吸附剂的ф0.9×200毫米的石英棒代替通常的薄层层析板,将样品点于棒端,按一般的薄层色谱法展开分离。展开后挥发除去展开剂,被分离的样品组份斑点留在棒上,然后直接通过FID的火焰进行定量分析。该仪器较过去的光学扫描仪具有结构及操作简单,制造较易,应用范围广及线性范围宽等特点。本文对薄层棒色谱法和FID扫描仪的操作方法和操作条件进行了研究。     

Flow injection-pulse amperometric detection of ephedrine at a cobalt phthalocyanine modified carbon paste electrode

Direct detection of ephedrines and other underivatized amino compounds (amines, alicyclic amines, alkanolamines, and amino acids) can be carried out via electrocatalytic oxidation at a carbon paste electrode (CPE) modified with cobalt phthalocyanine (CoPC) in alkaline solution (0.10 mol L-1 NaOH). Most of the amino compounds tested could be determined using the CoPC/CPE in an amperometric flow detector. The analytical signal of ephedrine was stabilised by alternating the potential between an anodic detection potential of +0.30 V (+0.45 V for other amino compounds) applied for 220 ms and a cathodic reactivation potential of -0.30 V applied for 100 ms (potentials versus SCE). The linear response range for ephedrine was within 1-100 mumol L-1 and the detection limit was 0.8 mumol L-1 with a 100 microL sample loop and a typical sampling ra 60 h-1. The signal (oxidation peak current) reproducibility was 2-3%. The method was applied to the determination of ephedrine in pharmaceutical formulations with results comparable to those obtained with a standard spectrophotometric method.     

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     

Electrochemistry and chromatographic detection of monosaccharides,disaccharides, and related compounds at an electrocatalytic chemically modified electrode

Many carbohydrate compounds undergo electro-oxidation at modest positive potentials at chemically modified electrodes (CMEs) made by adding cobalt phthalocyanine (CoPC) electrocatalyst to a conventional carbon paste mixture. The active carbohydrates which were oxidized at the CME at +0.4 to 0.5 V vs. Ag/AgCl under the very basic pH conditions required, included not only monosaccharides but also oligosaccharides, deoxy sugars, and even simple polyalcohols such as glycerol. When used for carbohydrate detection after liquid chromatography, the CoPC CME yielded detection limits in the 10–50 pmol range. Electrode stability and selectivity was such that no sample preparation other than dilution and particulate filtration was required for carbohydrate determinations in sample matrices including food products and physiological fluids.     

Detecting thiols in a microchip device using micromolded carbon ink electrodes modified with cobalt phthalocyanine

This paper describes the fabrication and evaluation of a chemically modified carbon ink microelectrode to detect thiols of biological interest. The detection of thiols, such as homocysteine and cysteine, is necessary to monitor various disease states. The biological implications of these thiols generate the need for miniaturized detection systems that enable portable monitoring as well as quantitative results. In this work, we utilize a microchip device that incorporates a micromolded carbon ink electrode modified with cobalt phthalocyanine to detect thiols. Cobalt phthalocyanine (CoPC) is an electrocatalyst that lowers the potential needed for the oxidation of thiols. The CoPC/carbon ink composition was optimized for the micromolding method and the resulting microelectrode was characterized with microchip-based flow injection analysis. It was found that CoPC lowers the overpotential for thiols but, as compared to direct amperometric detection, a pulsed detection scheme was needed to constantly regenerate the electrocatalyst surface, leading to improved peak reproducibility and limits of detection. Using the pulsed method, cysteine exhibited a linear response between 10-250 microM (r(2) = 0.9991) with a limit of detection (S/N = 3) of 7.5 microM, while homocysteine exhibited a linear response between 10-500 microM (r(2) = 0.9967) with a limit of detection of 6.9 microM. Finally, to demonstrate the ability to measure thiols in a biological sample using a microchip device, the CoPC-modified microelectrode was utilized for the detection of cysteine in the presence of rabbit erythrocytes.     

Simplification of determination method for standard materials using post-column reaction GC/FID

For the simple and fast preparation of highly reliable standard materials, a post-column reaction GC/FID system was developed and evaluated on the mixture of oxygen-containing organic compounds. The oxygen-containing organic compounds mixing solution were determined with the post-column reaction GC/FID system using n-dodecane as an internal calibration standard. Required value of relative expanded uncertainty as an original source of SI-traceable standard materials was within 1% and it aimed at this value as accuracy of the quantitative analysis. The results showed good agreement between the prepared concentrations and analytical values using post-column reaction GC/FID system. These results indicated that the post-column reaction GC/FID system would be used for getting SI-traceable values.     

气相色谱/氢火焰离子化检测法分析烷基化物料中的C4氟代烃

以实验室合成的氟代叔丁烷、氟代仲丁烷、氟代正丁烷为参考,建立了烷基化物料中C4氟代烃的气相色谱/氢火焰离子化检测(GC/FID)分析方法。提出了利用气相色谱/原子发射光谱(GC/AED)按元素响应的特点求算C4氟代烃在GC/FID上相对校正因子的方法。方法采用OV-225(50 m×0.25 mm i.d.×0.25 μm)和SE-54(44 m×0.22 mm i.d.×0.25 μm)串联柱为分析柱,FID为检测器,校正归一化或间接外标方法进行定量,具有重复性好、应用移植便利、操作简单等特点,对氟代叔     

Determination of an Ethylene Bisdithiocarbamate Based Pesticide (Nabam) by Cobalt Phthalocyanine Modified Carbon Ink Electrode

A phthalocyanine based sensor, for anodic detection of sodium ethylene bisdithiocarbamate (Nabam) by coating a mixture of cobalt phthalocyanine (CoPC) modified carbon ink on the surface of a glassy carbon electrode, has been described. The modified ink was prepared by mixing three percent of cobalt phthalocyanine into carbon ink and then diluting the mixture with cyclohexanone in w/w ratio of 1/9. A suitable portion (or 1 μL) of ink mixture was then dip‐coated on a rotating disk glassy carbon electrode. The modified ink electrode was air‐dried for 15 mins before use. In comparison to the bare ink electrode on which the oxidation of Nabam takes place at 300 mV (vs. 3 M Ag/AgCl), the oxidation potential (?125 mV) of Nabam at the CoPC modified ink decreases significantly. A typical calibration plot of Nabam proportionally increases over the concentration range of 2.5 to 36 μM (R=0.9990). The detection limit is estimated about 28.8 nM (S/N=3) and its response time (between 10% to 90% of steady‐state response) is about 5.3 s at the injection of 5 μM Nabam. The sensitivity requirement of JMPR meeting (Joint FAO/WHO Meeting on Pesticide Residues) for ethylene bisdithiocarbamates (EBDCs) is achieved by this proposed scheme.     

色谱与色谱/质谱法相结合分析热裂解汽油C9馏分

采用毛细管气相色谱-氢火焰离子化检测器（CGC-FID）和气相色谱-质谱法(GC/MS)分析了热裂解汽油C9 馏分的组成。实验使用PONA毛细管气相色谱柱(100 m×0.25 mm i.d.×0.5 μm),根据烃类化合物在PONA柱上的保留规律,以正构烷烃标样保留值作为碳数分布依据,定量分析了裂解汽油C9 馏分中烃类化合物的碳数分布和单体烃含量;用GC/MS联用技术和CGC保留值定性法相结合对裂解汽油C9 馏分中相对含量大于0.2%的39种化合物进行了定性。     

Metrological effectiveness of an analytical method for volatile organic compounds standard materials using post-column reaction GC/FID system

The metrological effectiveness of an analytical method using the post-column reaction GC/FID system was evaluated. The SI-traceable certified reference material (CRM), the eight ester phthalates mixture standard solution, was used as a sample. We assigned specific value to n-eicosane and it was used as an internal standard. A known quantity of n-eicosane was added to the CRM, and the mixture was measured with the post-column reaction GC/FID system. Six phthalate esters were chromatographically separated and determined. The assigned values by our system are in good agreement with the certified values of the CRM, and the combined uncertainties of the measurements by the present system were better than those of the CRM. Our method is classified as a primary ratio method and the specific values of many organic compounds can be assigned very precisely by using a small number of reference materials. Also, the method can make it possible to avoid the purity determination of raw materials and directly to assign their specific values after the preparation of the standard mixture. Conclusively, this post-column reaction GC/FID system is very effective for the chemical metrology.     

Analysis of polynuclear aromatic hydrocarbons by glass capillary gas chromatography using simultaneous flame ionization and electron capture detection

The possibility of simultaneous application of an electron capture (ECD) and a flame ionization detector (FID) connected to a glass capillary column for analyzing polynuclear aromatic hydrocarbons (PNA) has been investigated. The ECD/FID ratio is determined for 46 PNA compounds. The ratios vary from 0.02 to 117 with relative standard deviations better than 20 percent determined from 10 replicate analyses. The results suggest that the method may be used for obtaining additional evidence in identifying PNA in environmental samples. Impurities and transformation products in the standard were identified by computerized glass capillary gas chromatography/mass spectrometry. Quinones and diones are responsible for the high EC-response determined in some trace components in the standard. An application of the method is shown for PNA from particulates in urban atmospheres.