丙基格林试剂的合成及其在丁基锡衍生反应中的应用

格林试剂衍生方法是气相色谱与元素选择性检测器分离和测定有机锡化合物样品前处理的一个重要环节。研究了丙基格林试剂的实验室合成及其在丁基锡化合物衍生反应中的应用,为这类化合物监测标准方法的建立提供了基础条件。     

In-capillary derivatization and determination of iodine in sodium chloride solution

A new capillary electrophoretic (CE) method was developed for the simple and selective determination of iodine in 0.5 mol l(-1) NaCl. The proposed method is based on the in-capillary derivatization of iodine with thiosulfate ions using the zone-passing technique and direct photometric detection of the iodide and tetrathionate formed. The optimal conditions for the separation and derivatization reaction were established by varying the concentration of iodine, electrolyte pH and applied voltage. The optimized separations were carried out in phosphate electrolyte (pH 6.86) using direct photometric detection at 253.7 nm. Common photometric detection absorbing anions such as Cl(-), NO(2)(-), S(2)O(3)(2-) did not give any interference. Valid calibration (r(2) = 0.994) is demonstrated in the range 16.5-198.1 mg l(-1) of iodine. The detection limit (calculated according to K. Doerffel, Statistik in der analytischen Chemie, 1990) was 11.53 mg l(-1) (by iodide peak area) and 8.45 mg l(-1) (by tetrathionate peak area). The proposed system was applied to the determination of iodine after oxidation of iodide in underground water.     

高效液相色谱-光度法测定金属离子的进展

评述了近年以来柱前衍生高效液相色谱一光度法分析痕量金属离子的进展,并简要介绍了一些新方法（引述文献61篇）。     

Gas chromatographic determination of primary alcohols as their formylbenzoic esters by gas-phase luminescence detection.

A new and convenient method is described for the derivatization of primary alcohols with p-formylbenzoyl chloride, and the sensitive photometric detection of the resulting formylbenzoic ester derivatives based on their gas-phase luminescence in excited nitrogen. The coupling reaction proceeds rapidly and quantitatively, and the formylbenzoic esters show good GC properties. The minimum detectable amounts of the derivatized alcohols, at a signal three-times the peak-to-peak noise, lie between 10 and 100 pg per injection, and their linear ranges cover approximately three-orders of magnitude.     

Determination of Part-Per-Billion Levels of Formaldehyde in Aqueous Solution by Ion Chromatography with Post-Column Derivatization

Abstract

A method based on the use of an ion-exchange column, post-column derivatization with 2,4-pentane-dione (acetylacetone), and photometric detection for the determination of low levels of formaldehyde in aqueous solution is described. The lower limit of detection is 5 μg/L (ppb) and response is linear up to at least 10 mg/L. Reproducibility at the 1 mg/L level is 0.6% RSD. Determination of formaldehyde concentration in several aldehyde systems is demonstrated.     

微柱高效液相色谱与火焰光度检测器联用研究

报道了微柱高效液相色谱（micro-column HPLC）与火焰光度检测器（FPD）在线联用系统的研究,目的是发展一种不经复杂前处理步骤即可直接测定有机锡化合物的方法。三丁基锡氯化物（TBT）等经HPLC微柱分离后,通过毛细管连接引入特制的燃烧头,通过火焰光度检测器进行检测,对系统有关参数进行了优化和讨论。所建方法可以直接测定各种水样中的三丁基锡氯化物。     

Comparison of the sensitivities of seven N-nitrosamines in pre-screened waters using an automated preconcentration system and gas chromatography with different detectors

A simple, expeditious procedure for confirming the presence of N-nitrosamines in previously screened positive water samples was proposed. Water samples were continuously aspirated into a photometric flow system for screening. Positive samples were then confirmed and N-nitrosamines were identified by gas chromatography using different detectors (mass spectrometry, flame ionization and nitrogen-phosphorus). The system for the screening purpose was based on the preconcentration of the analytes onto a sorbent column, elution, and derivatization to form nitrite, then formation of a coloured product (Griess reaction) and photometric detection. The detection limits of the gas chromatographic method for 100 ml of sample were 2.0-3.5 microg/l, 20-80 and 3-13 ng/l for flame ionization, nitrogen-phosphorus and mass spectrometric detectors, respectively. The precision as RSD was similar for all detectors (3.0-6.5%). The screening of different types of water showed that wastewaters contain levels of N-nitrosamines that can be detected only using MS as a detector.     

Determination of biologically active low-molecular-mass thiols in human blood. I. Fast qualitative and quantitative, gradient and isocratic reversed-phase high-performance liquid chromatography with photometric and fluorescence detection

The fast isocratic and gradient reversed-phase high-performance liquid chromatographic methods employing photometric and/or fluorescence detection are described for the precise reproducible simultaneous measurement of total homocysteine, cysteine, and glutathione in human blood. Sample preparation involves conversion of disulfides to free thiols with triphenylphosphine, precipitation of proteins with sulfosalicylic acid, and conjugation of thiols with monobromobimane. The aminothiol assay is optimized by reduction and derivatization step conditions (pH, temperature and time of reactions), as well as by chromatographic conditions to obtain reliable quantitative results within the concentration range corresponding to the levels of these thiols in human blood in norm and pathology. Its sensitivity allows the detection of aminothiol quantities >2 pmol.     

Organotin speciation analyses in marine biota using sodium tetraethylborate ethylation and gas chromatography with flame photometric detection

The analysis of organotin compounds based on the in situ simultaneous derivatization and extraction with sodium tetraethylborate has been optimized to overcome the most common matrix effect problems with biological samples. To obtain a complete dissolution of the samples, free of colloidal interfaces problems, mechanical agitation has been coupled with stirring in a warmed ultrasonic bath. A strict quality control system using three internal standards was implemented. Tripropyltin chloride was used as internal standard to assess the derivatization reaction and tetraoctyltin was used to check the overall extraction efficiency. Tetrabutyltin was used to verify the gas chromatography (with flame photometric detector) performance of the analyses. The technique was validated using Certified Reference Materials (NIES‐11 and BCR‐477) and has been applied successfully to different biological matrices (fish, mussels, oyster and barnacles). Copyright © 2002 John Wiley & Sons, Ltd.     

Analytical methodology for organophosphorus pesticides used in Canada

An overview of analytical methodology for the determination of organophosphate pesticides residues in foods is presented. Sample extraction is carried out with acetone followed by a dichloromethane-hexane partition. The organic extract is purified by automated gel permeation chromatography and analysed by capillary gas chromatography with flame photometric or thermionic detection. Confirmation can be carried out by a variety of chemical derivatization techniques including hydrolysis followed by reaction of the phosphate or phenol moiety, direct alkylation or trifluoracetylation. Thin-layer chromatography with enzyme inhibition detection can be used as a rapid screening technique or to confirm results obtained by gas chromatography. Liquid chromatography has not been used much for the determination of organophosphorus compounds in foods.