Electrochemical detector in high-performance

Bollet, C., Oliva, P., and Caude, M., Partial electrolysis electrochemical detector in high-performance liquid chromatography, /. Chromatogr., 149,625,1977. 

AN Masoud, Y N Cha. Simultaneous use of fluorescence, ultraviolet, and electrochemical detectors in high performance liquid chromatography-separation and identification of phenolic antioxidants and related compounds. J High Resolut Chromatogr Comm 5 299-305, 1982. 

Chromatopolarography appeared to be an important method, because on a well-chosen chromatographic column, substances which had almost identical voltam-metric characteristics (half-wave potentials) could be separated, if their affinities to the column-filling material (stationary phase) were sufficiently different. After separation, they could be polarographically detected and their content determined. This method may be considered a precursor of many combined voltammetric techniques developed in forthcoming years and specifically electrochemical detectors in high performance liquid chromatography (HPLC) and microfluidics. 

L. Brunt, Electrochemical detectors for high-performance liquid chromatography and flow analysis systems, in Trace Analysis, vol. I, Ed. J. Lawrence, Academic Press, 1981. 

H. W. van Rooijen and H. Poppe, An Electrochemical Reactivation Method for Solid Electrodes Used in Electrochemical Detectors for High-Performance Liquid Chromatography and Flow Injection Analysis. Anal. Chim. Acta, 130 (1981) 9. 

C.N. Svendsen, Multi-electrode array detectors in high-performance liquid chromatography A new dimension in electrochemical analysis. Analyst, 1993, 118, 123-129. 

Nagels, L.J., Creten, W.L. (1985). Evaluation of the glassy carbon electrochemical detector selectivity in high-performance liquid chromatographic analysis of plant material. Anal. Chem. 57, 2706. 

Poppe, H. Electrochemical detectors. In Instrumentation for High-Performance Liquid Chromatography, Huber, J.F.K., Ed. Elsevier Amsterdam, 1978, pp. 131-149. 

The refiactive index detectitm (RID), often used in high-performance liquid chromatography (HPLC), is an interesting detection method in CE with a laser light source and a hmit of detection (LOD) in the micromolar range. Electrochemical detection (ECD) and pulsed amperometric detection (PAD) of sugars are common and effective methods used in HPLC. Some recait communications show that the sensitivity of these detection methods in CE have an approximately 1000-fold better LOD than RID. Unfortunately, these detectors (RID, ECD, and PAD) are not commercially available for CE at the moment... 

G. Forzy, J.L. Dhondt and J.M. Hayte, Comparison of 11 electrochemical detectors used in high performance liquid chromatography, Ann. Biol. Clin. (Paris), 1988, 46, 793-793. 

OPTIMIZATION OF AN ELECTROCHEMICAL DETECTOR USING A STATIC MERCURY DROP ELECTRODE IN HIGH-PERFORMANCE LIQUID CHROMATOGRAPHY ANALYSIS OF THE ANTICANCER AGENT MITOMYCIN C IN PLASMA... 

High-performance liquid chromatography (HPLC) with a micellar mobile phase or with a selective pre-column or reaction detection system has also been used to determine alkylenebis(dithiocarbamaes). ° Zineb and mancozeb residues in feed were determined by ion-pair HPLC with ultraviolet (UV) detection at 272 nm. These compounds were converted to water-soluble sodium salts with ethylenediaminetetra-acetic acid (EDTA) and sodium hydroxide. The extracts were ion-pair methylated with tetrabuthylammonium hydrogensulfate (ion-pair reagent) in a chloroform-hexane solvent mixture at pH 6.5-8.S. The use of an electrochemical detector has also been reported. ... 

Nagaosa et al. [839] simultaneously separated and determined these elements in seawater by high-performance liquid chromatography (HPLC) using spec-trophotometric and electrochemical detectors. 

High-performance liquid chromatographic separation with electrochemical detection may provide the best sensitivity for phenol quantification in biological samples. The use of gas chromatography with a flame ionization detector may be a more versatile method, if other non-ionic pollutants must be quantified. The advantages and disadvantages of different methods available for the quantification of phenol and metabolites in biological and environmental samples have been discussed by Tesarova and Packova(1983). 

GC = gas chromatography EC = electrochemical (detector ECD = electron capture (detector HCD = Hall conductivity detector HFBA = heptafluorobutyric anhydride HPLC = high performance liquid chromatography NCI-MS = mass spectrometry in the negative chemical ionization mode NPD = nitrogen-phosphorus detector ppb = parts per billion UV = ultraviolet absorption SPE = solid phase extraction wt wt = weight weight... 

High-performance LC was also used for determination of TBZ after its extraction from marmalades and curds with ethyl acetate (13). The use of a buffered mobile phase improved the response of the UV detector, and column performance remained constant throughout 2 months of daily use with a detection limit of 100 ppb. Three detectors (UV, fluorimetric, and electrochemical) were used for the determination of OPP, BP, and TBZ in plant materials (45). The compounds were extracted with dichloromethane and separated on an RP-18 column with a methanolic formic acid buffer as eluent. It was not possible to determine TBZ using an electrochemical detector, although the extraction recovery varied between 80 and 95%. 

Direct determination of urea pesticides by high-performance liquid chromatography has been widely reported in the literature (10,32-36,127-130). Ultraviolet detection has often been used (32,33,35,36,60,127) with usually acceptable sensitivity, although this detector is nonspecific and the sensibility is, in general, low. To overcome this problem, several techniques have been assayed, such as precolumn enrichment (60), postcolumn derivatization (34,10), and the use of other detection techniques such as the electrochemical (129), photoconductivity (128,130), and fluorescence detectors (9,10,34). Table 9 summarizes representative papers using these techniques in HPLC analysis. 

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