Detectors capillary zone electrophoresis

AMPA = aminomethylphosphoric acid, CZE = capillary zone electrophoresis, DAD = = diode array detector. MEKC =... 

Wu S, Dovichi NJ (1989) High-sensitivity fluorescence detector for fluorescein isothiocyanate derivatives of amino acids separated by capillary zone electrophoresis. J Chromatogr 480 141-155... 

Gotti et al. [42] reported an analytical study of penicillamine in pharmaceuticals by capillary zone electrophoresis. Dispersions of the drug (0.4 mg/mL for the determination of (/q-penicillaminc in water containing 0.03% of the internal standard, S -met hy I - r-cystei ne, were injected at 5 kPa for 10 seconds into the capillary (48.5 cm x 50 pm i.d., 40 cm to detector). Electrophoresis was carried out at 15 °C and 30 kV, with a pH 2.5 buffer of 50 mM potassium phosphate and detection at 200 rnn. Calibration graphs were linear for 0.2-0.6 pg/mL (detection limit = 90 pM). For a more sensitive determination of penicillamine, or for the separation of its enantiomers, a derivative was prepared. Solutions (0.5 mL, final concentration 20 pg/mL) in 10 mM phosphate buffer (pH 8) were mixed with 1 mL of methanolic 0.015% 1,1 -[ethylidenebis-(sulfonyl)]bis-benzene and, after 2 min, with 0.5 mL of pH 2.5 phosphate buffer. An internal standard (0.03% tryptophan, 0.15 mL) was added and aliquots were injected. With the same pH 2.5 buffer and detection at 220 nm, calibration graphs were linear for 9.3-37.2 pg/mL, with a detection limit of 2.5 pM. For the determination of small amounts of (L)-penicillamine impurity, the final analyte concentration was 75 pg/mL, the pH 2.5 buffer contained 5 mM beta-cyclodextrin and 30 mM (+)-camphor-10-sulfonic acid, with a voltage of 20 kV, and detection at 220 nm. Calibration graphs were linear for 0.5-2% of the toxic (L)-enantiomer, with a detection limit of 0.3%. 

CZE = capillary zone electrophoresis EC = electrochemical detector GC = gas chromatography HCD = Hall conductivity detector HPLC = high performance liquid chromatography IDMS = isotope dilution mass spectrometry MS = mass spectrometry RSD = relative standard deviation SEE = supercritical fluid extraction SPE = solid phase extraction UV = ultraviolet absorbance detection... 

Walbroehl, Y. and Jorgenson, J. W., On-column UV absorption detector for open tubular capillary zone electrophoresis, /. Chromatogr., 315, 135-143, 1984. 

Eberle et al. [134] separated the enantiomers of omeprazole and structurally related drugs by capillary zone electrophoresis with bovine serum albumin as chiral selector. The separations were carried out on a fused silica column (60 cm x 50 pm, 50 cm to detector) with a buffer consisting of 100-/zM-bovine serum albumin and 7% 1-propanol in 10 mM potassium phosphate pH 7.4. Electrokinetic injection was at 5-8 kV for 7 s. An applied voltage of 300 V/cm was used. Detection was at 290 nm. Detection limits were 0.04 mg/ml for the analytes studied. 

Capillary Zone Electrophoresis. The primary advantage of capillary electrophoresis can be found in the simplicity of the instrument. Basic experimental components include a high-voltage power supply, two buffer reservoirs, a fused silica capillary, and a detector. The basic setup is usually completed with enhanced features such as multiple injection devices, autosamplers, sample and capillary temperature controls, programmable power supplies, multiple detectors, fraction collection, and computer interfacing. 

Multiple stages (n) of mass spectrometry in sequence Nonaqueous capillary zone electrophoresis Nitrogen-phosphorus detector Quadrupole/time-of-flight analyzer Relative standard deviation... 

Liu, Y. and Lopez-Avila (1993) On-line microwave-induced helium plasma atomic emission detector for capillary zone electrophoresis./. High Resol. Chromatogr., 16, 717-720. 

Rg.1 Detection of microheterogeneity of albumin chicken egg by capillary zone electrophoresis. Capillary, bare fused-silica (50 jum X 37 cm, 30 cm to the detector) electrolyte solution, 25 mM Tris-glycine buffer containing 0.5% (v/v) Tween-20 and 2.0 mM putres-cine applied voltage, 20 kV UV detection at the cathodic end. 

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