UV detection electrophoresis

Kaale, E., Van Goidsenhoven, E., Van Schepdael, A., Roets, E., and Hoogmartens, J. (2001). Electrophoretically mediated microanalysis of gentamicin with in-capillary derivatization and UV detection. Electrophoresis 22, 2746—2754. 

Suzuki, S., Ishida, Y., Arai, A., Nakanishi, H., and Honda, S. (2003). High-speed electrophoretic analysis of l-phenyl-3-methyl-5-pyrazolone derivatives of monosaccharides on a quartz microchip with whole-channel UV detection. Electrophoresis 24, 3828—3833. 

Ludwig, M., Kohler, F., Beider, D., High-speed chiral separations on a microchip with UV detection. Electrophoresis 2003, 24, 3233-3238. 

Vegvaii, A. and Hjerten, S., A hybrid microdevice for electrophoresis and electrochromatography using UV detection. Electrophoresis, 23, 3479, 2002. 

Hgure 7 Simultaneous chiral separation of three basic drugs. Only about half of the total length of 25 mm of the microchip separation channel was needed to obtain complete resolution in 11s. Experimental conditions 25 mmol I triethylammonium phosphate buffer, pH 2.5, 5% highly sulfated y-cyclodextrin, UV detection at 200 nm. (Reproduced with permission from Ludwig M, Kohler F, and Beider D (2003) High-speed chiral separations on a microchip with UV detection. Electrophoresis 24 3233-3238 Wiley-VCH.)... 

We have developed the method for quantitative analysis of urinary albumin with CE. A capillary electrophoresis systems Nanophor 01 (Institute of Analytical Instmmentation, Russian Academy of Sciences, Saint-Petersburg) equipped with a UV-detector was used to determine analyte. Separation was achieved using 45 cmx30 p.m I.D. fused silica capillary column with UV-detection at 214 nm. 

Catechin and epicatechin are two flavanols of the catechin family. They are enantiomers. The capillary zone electrophoresis (CE) methods with UV-detection were developed for quantitative determination of this flavanols in green tea extracts. For this purpose following conditions were varied mnning buffers, pH and concentration of chiral additive (P-cyclodextrin was chosen as a chiral selector). Borate buffers improve selectivity of separation because borate can make complexes with ortho-dihydroxy groups on the flavanoid nucleus. 

Mato, 1., Huidobro, J. F., Simal-Lozano, J., and Sancho, M. T. (2006b). Simultaneous determination of nonaromatic organic acids in honey by capillary zone electrophoresis with direct UV detection. J. Agric. Food Chem. 54,1541-1550. 

Beck, W. and Engelhardt, H., Capillary electrophoresis of organic and inorganic cations with indirect UV detection, Chromatographia, 33, 313, 1992. 

Foret, F., Fanali, S., Nardi, A., and Bocek, P., Capillary zone electrophoresis of rare earth metals with indirect UV absorbance detection, Electrophoresis, 11, 780, 1990. 

FIGURE 16.8 HPLC chromatogram of cytochrome c and myoglobin digest, using a 250 cm x 4.6 mm ODS C18 Vydac column and a linear mobile-phase gradient, 5-50% B, in 50 min. Buffer A was 0.1% TFA in water and buffer B was 0.1 TFA in acetonitrile. UV detection was carried out at 214 nm, at room temperature (reprinted with permission from Electrophoresis). 

FIGURE 18.2 Capillary gel electrophoresis separation of an octylphenol ethoxylate sulfate (with an ethylene oxide chain length from 1 to 8). Run conditions pH 8.3 (100 mM tris-borate, 7 M urea) 50 pm x 75 cm J W polyacrylamide gel capillary (PAGE-5, 5%T, and 5%C) run at 20 kV with a 5kV injection for 5 s UV detection at 260nm. 

Figure 3.12 Metabolic profiling by capillary electrophoresis, (a) Comparative carbohydrate profiles of M. truncatula tissue obtained using 4-aminobenzonitrile derivatization, capillary electrophoresis with a 150 mM borate buffer, pH = 9, and on-column UV detection at 214 nm. (b) Anion profile from M. truncatula using capillary electrophoresis and indirect UV detection. The separation buffer was 5 mM K2C1O4, 1% Waters OFM-Anion BT, pH 8.0.

R. Loos, M.C. Alonso and D. Barcelo, Solid-phase extraction of polar hydrophilic aromatic sulfonates followed by capillary zone electrophoresis-UV absorbance detection and ion-pair liquid chromatography-diode array UV detection and electrospray mass spectrometry. J. Chromatogr.A 890 (2000) 225-237. 

B. Lagane, M. Treilhou and F. Couderc, Capillary electrophoresis theory, teaching approach and separation of oligosaccharides using indirect UV detection. Biochem. Mol. Biol. Educ. 28 (2000) 251-255. 

Fig. 3.161. (A) Zone electrophoresis patterns of FITC-labelled transferrin samples by fluorescence detection. The unbound dye (providing a main peak and several minor ones) was not removed from the samples. Experimental conditions background electrolyte, 100 mM borate buffer, pH 8.3 voltage, 20 kV capillary 59 cm (effective length 41 cm) X 75 pm i.d. injection of samples 100 mbar x s 20°C detection with fluorescence detector (240 - 400 nm, broadband excitation filter and a 495 nm cut-off emmision filter). The reaction was left to continue for 20 h, and the reaction mixtures contained 13 pm (1 mg/ml) Tf and (a) 0.01 mM FITC, (b) 0.1 mM FITC, and 1 mM FITC. (B) Zone electrophoresis patterns of an FITC-labelled transferrin sample by simultaneous fluorescence (upper trace, left axis) and UV detection (lower trace, right axis). The unbound dye shows several peaks with both detections. Experimental conditions background electrolyte, 100 mM borate buffer, pH 8.3 voltage, 20 kV capillary 59 cm (effective length fluorescence 41 cm, UV 50.5 cm) X 75 pm i.d. injection of samples 100 mbar X s 20°C detection with fluorescence detector (240 - 400 nm, broadband excitation filter and a 495 nm cut off emmision filter). The reaction was left to continue for 20 h, and the reaction mixtures contained 6.5 pm (0.5 mg/ml) Tf and 0.1 mM FITC. Reprinted with permission from T. Konecsni et al. [199].

With capillary electrophoresis (CE), another modern primarily analytically oriented separation methodology has recently found its way into routine and research laboratories of the pharmaceutical industries. As the most beneficial characteristics over HPLC separations the extremely high efficiency leading to enhanced peak capacities and often better detectability of minor impurities, complementary selectivity profiles to HPLC due to a different separation mechanism as well as the capability to perform separations faster than by HPLC are frequently encountered as the most prominent advantages. On the negative side, there have to be mentioned detection sensitivity limitations due to the short path length of on-capillary UV detection, less robust methods, and occasionally problems with run-to-run repeatability. Nevertheless, CE assays have now been adopted by industrial labs as well and this holds in particular for enantiomer separations of chiral pharmaceuticals. While native cyclodextrins and their derivatives, respectively, are commonly employed as chiral additives to the BGEs to create mobility differences for the distinct enantiomers in the electric field, it could be demonstrated that cinchona alkaloids [128-130] and in particular their derivatives are applicable selectors for CE enantiomer separation of chiral acids [19,66,119,131-136]. 

Mardones, C., Vizioli, N., Carducci, C., Rios, A., and Valcarcel, M. (1999). Separation and determination of carnitine and acyl-carnitines by capillary electrophoresis with indirect UV detection. Anal. Chim. Acta 382, 23—31. 

Ackermans, M. T., Everaerts, F. M., and Beckers, J. L. (1992). Determination of aminoglycoside antibiotics in pharmaceuticals by capillary zone electrophoresis with indirect UV detection coupled with micellar electrokinetic capillary chromatography.. Chromatogr. 606, 229—235. 

Wienen, F., and Holzgrabe, U. (2002). Characterization of paromomycin sulfate by capillary electrophoresis with UV detection after pre-capillary derivatization. Chromatographia 55,... 

Hilder, E. R, Klampfl, C. W., Buchberger, W., and Haddad, P. R. (2002). Comparison of aqueous and nonaqueous carrier electrolytes for the separation of penicillin V and related substances by capillary electrophoresis with UV and mass spectrometric detection. Electrophoresis 23, 414—420. 

Nickerson, B. (1997). The determination of a degradation product in clidinium bromide drug substance by capillary electrophoresis with indirect UV detection.. Pharm. Biomed. Anal. 15, 965-971. 

Stalberg, O., Sander, K., and Sanger-van de Griend, C. (2002). The determination of bromide in a local anaesthetic hydrochloride by capillary electrophoresis using direct UV detection.. Chromatogr. A 977, 265-275. 

Stalberg, O., Westerlund, D., Rodby, U. B., and Schmidt, S. (1995). Determination of impurities in remoxipride by capillary electrophoresis using UV-detection and LIF-detection — principles to handle sample overloading effects. Chromatographia 41, 287—294. 

Lurie, I. S. (1996). The analysis of cations and anions in illicit heroin using capillary electrophoresis with indirect UV detection. J. Capillary Electrophor. 3, 237-242. 

Liu, H., and Sunderland, V. B. (2004). Determination of sulfate in aminoglycoside antibiotics by capillary electrophoresis with indirect UV detection. J. Liq. Chromatogr. Related Technol. 27, 677—6S7. 

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