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Summary

Capillary electrophoresis with fluorescence detection has been investigated for simple, sensitive, and selective analysis of morphine and 6-acetylmorphine (6-AM) in human urine. The method is based on the reaction of morphine and 6-AM with the freshly prepared diazonium salt of aniline at 0°C. The method is selective in the presence of codeine. Conditions that affect derivatization (diazonium concentration and reaction time) and separation (electrolyte concentration, pH, β-cyclodextrin concentration, organic additives, and separation potential) were studied. When fluorescence detection was used with an excitation wavelength of 350 nm and an emission cutoff filter of 500 nm, good linearity was obtained in the range of 50–2000 ng mL–1 with limits of detection and quantification below 1.0 and 3.3 ng mL–1, respectively. The method was applied to human urine and validated by comparison with previously established capillary electrophoretic methods. Accuracy, repeatability, and intermediate precision of results were comparable. The method is suitable for application in forensic cases for initial screening, and in clinical analysis to prevent overdose-induced toxicity.

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) seeds and determination by capillary electrophoresis. J. Agric. Food Chem.47: 4649–4652. Kreft I. Extraction of rutin from buckwheat (Fagopyrum esculentum Moench) seeds and

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Summary

Formaldehyde in aquatic products was determined by micellar electrokinetic capillary chromatography (MEKC) after derivatization with 2,4-dinitrophenylhydrazine. Separation was carried out at 25 °C and 25 kV, using a fused silica capillary (75 µ internal diameter; 50.5 cm effective length) and an ultraviolet detector set at 360 nm. The optimal background electrolyte was 20 mM sodium tetraborate and 20 mM sodium dodecyl sulfate at pH 9.0 with 3 s hydrodynamic injection at 30 mbar. Electrophoretic analysis took approximately 6.5 min. The correlation coefficient of the calibration curve was 0.999 over the concentration range 2.0–100.0 mg L−1, and the LOD and LOQ values were 0.57 and 1.89 µg mL−1, respectively. The recoveries were from 83.7% to 97.2% with steam distillation as the sample pretreatment method.

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Cereal Research Communications
Authors: I. Baracskai, G. Balázs, L. Liu, W. Ma, M. Oszvald, M. Newberry, S. Tömösközi, L. Láng, Z. Bedő, and F. Békés

, Z. 2000. Study of the LMW glutenin composition of some old Hungarian wheat cultivars using capillary electrophoresis. Cereal Res. Commun. 28 :417–424. Bedõ Z. Study of the LMW

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Acta Alimentaria
Authors: G. Balázs, I. Baracskai, M. Nádosi, A. Harasztos, F. Békés, and S. Tömösközi

-on-a-Chip capillary electrophoresis. —in: Black, C.K., Panozzo, J.F. & Rebetzke, G.J. (Eds), Proceedings of the 54th Australian Cereal Chemistry Conference and the 11th Wheat Breeders’ Assembly . Royal Australian Chemical Institute, Melbourne, pp. 411

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Vasas, G., Gáspár, A., Páger, Cs., Surányi, Gy., M-Hamvas, M., Máthé, Cs., Borbély, Gy. (2004) Analysis of cyanobacterial toxins (anatoxin-a, cylindrospermopsin, microcystin-LR) by capillary electrophoresis. Electrophoresis 25 , 108

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Five species of Plantago genus, namely P. lanceolata, P. major, P. media, P. altissima and P. maritima were screened for iridoid content (CE-MEKC), total caffeoyl phenylethanoid glycoside (CPG) content and antioxidant activity (CUPRAC assay). The five species could be distinguished by TLC pattern analysis in a single run in a system commonly used for quality management of P. lanceolata leaves, as shown by cluster analysis of major bands; with the exception, that P. altissima and P. lanceolata did not show enough pattern difference to be fully separated. P. maritima was shown to have the highest antioxidant capacity (0.42 μmol ascorbic acid equivalent (AAE)/g DW), and the highest level of CPGs (4.29%). P. altissima was shown to be chemically indistinguishable from P. lanceolata with repsect to iridoid content (aucubin 0.55 ± 0.04%, 0.68 ± 0.23%, catalpol 0.66 ± 0.13% and 0.89 ± 0.22%, respectively), CPG content (2.40 ± 0.38% and 2.54 ± 0.56%, respectively) and antioxidant capacity (0.2206 ± 0.0290 and 0.2428 ± 0.0191 μmol AAEAC/g DW). The presented data show the potency of medicinal use of Hungarian wild populations of the studied five species, especially in the case of P. maritima, and that P. altissima can be a potential replacement of P. lanceolata in herbal mixtures.

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Summary

Formaldehyde in aquatic products was determined by micellar electrokinetic capillary chromatography (MEKC) after derivatization with 2,4-dinitrophenylhydrazine. Separation was carried out at 25 °C and 25 kV, using a fused silica capillary (75 µ internal diameter; 50.5 cm effective length) and an ultraviolet detector set at 360 nm. The optimal background electrolyte was 20 mM sodium tetraborate and 20 mM sodium dodecyl sulfate at pH 9.0 with 3 s hydrodynamic injection at 30 mbar. Electrophoretic analysis took approximately 6.5 min. The correlation coefficient of the calibration curve was 0.999 over the concentration range 2.0–100.0 mg L−1, and the LOD and LOQ values were 0.57 and 1.89 µg mL−1, respectively. The recoveries were from 83.7% to 97.2% with steam distillation as the sample pretreatment method.

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Acta Veterinaria Hungarica
Authors: László Fésüs, Attila Zsolnai, István Anton, and László Sáfár

The first results of the Hungarian sheep prion protein (PrP) genotyping programme are discussed in this paper. To obtain initial genotype frequency data 10 commercial (Hungarian Merino, German Mutton Merino, Merino Landschaf, German Blackheaded, Suffolk, Texel, Ile de France, Charollais, Lacaune, British Milksheep) and 4 indigenous (Gyimes Racka, Hortobágy Racka, Tsigaja, Cikta) breeds were sampled in 2003 and 2004, and the PrP genotypes were determined by microsequencing analysis with capillary electrophoresis. In all commercial breeds, a higher number of sheep were genotyped in 2005 (3648) and in 2006 (3834) within the breeding programme to increase scrapie resistance, and the estimated frequency data were compared to the initial figures to evaluate the efficiency of selection. The new developments arising from the identification of the so-called ‘atypical’ scrapie cases are also discussed.

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Abstract  

A large group of radiopharmaceuticals includes complex radionuclide-ligand compounds which are very sensitive to the preparation conditions, as for example pH of reaction mixture, incubation time, temperature, molar ratio of reagents, etc. It is necessary to find the optimum condition for the formation of the radionuclide-ligand complex and to select the convenient analytical methods to determine the purity of the product. The preparation of radiopharmaceuticals labeled by rhenium-186 or rhenium-188 requires the addition of a reducing agent (commonly stannous chloride) to the reaction mixture in order to reduce perrhenate to a lower oxidation state which is capable of complex formation. For rhenium concentration up to approximately 10-5 mol/l, the molar excess of reduction agent over perrhenate is usually higher than 800 to reach the optimum yield of reduction and complexation (between 80-95%). Because of the potentially toxic effect of SnCl2 the reduction of perrhenate by stannous chloride was studied in detail to find the way for decreasing the concentration of reducing agent in the reaction mixture without significant lowering of the yield of perrhenate reduction. The reduction of perrhenate was determined by electromigration methods, i.e., capillary electrophoresis (CZE) and isotachophoresis (ITP), and thin-layer chromatography (TLC) with radiometric detection. The highest degree of reduction of perrhenate was obtained at pH 2 at perrhenate concentration ranging from 10-4 to 10-3 mol/l. The stability of reduced rhenium against a pH change from 2 to 5.5 (which corresponds to the pH close to physiological values) was tested as well. The influence of the presence of ascorbic acid as an antioxidant in the reaction mixture on the stability of the preparation against the pH change was determined. The stability of reduced rhenium against dilution of rhenium in the reaction mixture to the concentration suitable for the application in radiotherapy was also found out. The data acquired by capillary electrophoresis, isotachophoresis and thin-layer chromatography are comparable. Results obtained in these experiments were applied for the study of rhenium complexes with hydroxyethylidenediphosphonic acid (HEDP).

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