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1.
Kaale E Leonard S Van Schepdael A Roets E Hoogmartens J 《Journal of chromatography. A》2000,895(1-2):67-79
A selective, sensitive, and rapid pre-capillary derivatization method for determination of the multicomponent aminoglycoside antibiotic gentamicin is described. The derivatization reagents 1,2-phthalic dicarboxaldehyde and mercaptoacetic acid were used and the thioisoindole derivative was UV detected at 330 nm. A central composite experimental design was performed to optimize selectivity and derivatization conditions. Baseline separation of gentamicin C1, C1a, C2, C2a, C2b, sisomicin and several minor components was achieved with a background electrolyte containing 30 mM sodium tetraborate, 7.5 mM beta-cyclodextrin and 12.5% (v/v) methanol at pH 10. Quantitative analysis was performed and illustrated the potential use of capillary electrophoresis for the identification and quantitation of gentamicin as an alternative to methods prescribed in the United States Pharmacopeia and European Pharmacopoeia. 相似文献
2.
Kang J Vankeirsbilck T Van Schepdael A Orwa J Roets E Hoogmartens J 《Electrophoresis》2000,21(15):3199-3204
A method for the quantitative analysis of colistin sulfate by capillary zone electrophoresis is described. Since colistin components have five free amino groups, they tend to adsorb onto the capillary wall and cause peak tailing. It was found that triethanolamine (TEA)-phosphate buffer at pH 2.5 was useful to reduce such adsorption. Methyl-beta-cyclodextrin (M-beta-CD) and 2-propanol (IPA) were found necessary for selectivity enhancement. In order to optimize the separation parameters and predict the method robustness, a central composite design was performed including three variables, namely concentration of M-beta-CD, TEA, and IPA. The effects of capillary length and applied voltage on separation were also investigated. The optimal conditions established were: 140 mM TEA-phosphate buffer containing 5 mM M-beta-CD and 6% v/v IPA, a capillary with 55 cm total length (50 microm inner diameter, 47 cm from inlet to detection window) and 24 kV applied voltage. The method was found to be robust when the variables were changed in the following range: 4-6 mM M-beta-CD, 5-7% v/v IPA, and 130-150 mM TEA. Further, the linearity, limit of detection (LOD), and limit of quantitation (LOQ), as well as repeatability for both colistin A and B were examined and three commercial samples were quantitatively analyzed. 相似文献
3.
Debremaeker D Visky D Chepkwony HK Van Schepdael A Roets E Hoogmartens J 《Rapid communications in mass spectrometry : RCM》2003,17(4):342-350
A selective reversed-phase liquid chromatography/mass spectrometry (LC/MS(n)) method is described for the identification of azithromycin impurities and related substances in commercial azithromycin samples. Mass spectral data are acquired on an LCQ ion trap mass spectrometer equipped with an atmospheric pressure chemical ionization interface operated in positive ion mode. The LCQ provides on-line LC/MS(n) capability, making it ideally suited for identification purposes. In comparison with UV detection, this hyphenated technique provides as its main advantage efficient identification of novel substances without time-consuming isolation and purification procedures. Using this technique, six novel related substances detected in commercial azithromycin samples have been studied. 相似文献
4.
Investigation of unknown related substances in commercial erythromycin samples with liquid chromatography/mass spectrometry 总被引:1,自引:0,他引:1
Govaerts C Chepkwony HK Schepdael AV Roets E Hoogmartens J 《Rapid communications in mass spectrometry : RCM》2000,14(10):878-884
A selective reversed phase liquid chromatography/mass spectrometry (LC/MS(n)) method is described for the identification of erythromycin impurities and related substances in commercial erythromycin samples. Mass spectral data are acquired on a LCQ ion trap mass spectrometer equipped with an electrospray interface operated in positive ion mode. The LCQ is ideally suited for identification of impurities and related substances because it provides on-line LC/MS(n) capability. Compared with UV detection, this hyphenated LC/MS(n) technique provides as a main advantage efficient identification of novel substances without time-consuming isolation and purification procedures. Using this method four novel related substances were identified in commercial samples. 相似文献
5.
JPC – Journal of Planar Chromatography – Modern TLC - A quantitative thin layer chromatographic (TLC) method on silica gel, with ethyl acetate–acetone–alcohol, 62 + 40 + 3... 相似文献
6.
J. Paesen A. Solie E. Roets J. Hoogmartens 《Fresenius' Journal of Analytical Chemistry》1995,352(7-8):797-800
An isocratic liquid chromatographic method for the assay and purity control of josamycin using wide-pore poly(styrene-divinylbenzene) as the stationary phase is presented. Josamycin has been well separated from all the related leucomycins, present as impurities in commercial samples. Wide-pore PLRP-S 8 m 1000 Å has shown the best selectivity. The separation has been carried out at 65°C with a mobile phase of 2-methyl-2-propanol/0.2 mol/l potassium phosphate buffer pH 10.5/water (24.5: 5: 70.5, V/V) and a flow rate of 1.0 ml/min. UV detection has been performed at 232 nm. The total analysis time has been about 40 min. The method has been used to analyse commercial bulk samples and tablets containing josamycin base.Dedicated to Professor Dr. Dr. h.c. mult. J.F.K. Huber on the occasion of his 70th birthday 相似文献
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8.
Electrophoretically mediated microanalysis of gentamicin with in-capillary derivatization and UV detection. 总被引:2,自引:0,他引:2
E Kaale E Van Goidsenhoven A Van Schepdael E Roets J Hoogmartens 《Electrophoresis》2001,22(13):2746-2754
This paper describes a system for integration of a one-step-microscale chemical derivatization and analysis by a methodology known as electrophoretically mediated microanalysis (EMMA). Differential electrophoretic mobility between an analyte, reagent, and their product offers EMMA a unique capability to selectively carry out electrophoretic mixing, control product formation, and separation. This system was successfully applied to perform derivatization and separation of the multicomponent aminoglycoside antibiotic gentamicin using 1,2-phthalic dicarboxaldehyde and mercaptoacetic acid as labeling reagents. A multivariate approach based on central composite experimental design was used to optimize the derivative yield. Full automation of the derivatization and analytical procedure, high derivatization efficiency, high sample throughput, and precision are the excellent features of the present method. In addition, this methodology offers short analysis time, as well as selectivity and sensitivity suitable for impurities determination. Separation of gentamicin C1, C1a, C2, C2a, C2b, sisomicin, and several minor components was achieved. For the first time separation and identification of three impurities, namely garamine, 2-deoxystreptamine, and paromamine are described. 相似文献
9.
Iványi T Vander Heyden Y Visky D Baten P De Beer J Lázár I Massart DL Roets E Hoogmartens J 《Journal of chromatography. A》2002,954(1-2):99-114
This paper focuses on the classification or differentiation of RP-HPLC columns based on measured chromatographic properties. A chemometric study has been conducted on a published data set consisting of 85 RP-HPLC columns and on a data set consisting of 47 self-tested columns. Principal component analysis enables determination of the number of parameters necessary for a rational differentiation. The results show that reducing the number of parameters for such differentiation still allows classification of the columns just as a higher number did. It is shown that three test parameters produce a classification similar to that obtained with five parameters. 相似文献
10.
High-performance liquid chromatography on a Zorbax C8 7-micron column (25 cm X 0.46 cm I.D.) with methanol-water-1 M phosphoric acid (59:36:5) as the mobile phase has been used for the analysis of several naturally aged batches of fourteen brands of acetylsalicyclic acid tablets. The extraction solvent is methanol, containing 2% v/v of formic acid. Salicylic acid is the main impurity. Acetylsalicylsalicylic acid is the second most important impurity, and the corresponding salicylsalicylic acid is rarely present. Buffered or dispersible tablets contain relatively more of the latter two impurities and eventually also the corresponding higher oligomers. Acetylsalicylic anhydride is always a minor impurity. Comparison is made with classical spectrophotometric methods, which are observed to be selective for salicylic acid. 相似文献