| Autor: |
Kafka, Alexandra P., Rades, Thomas, McDowell, Arlene |
| Zdroj: |
Biomedical Chromatography; Feb2010, Vol. 24 Issue 2, p132-139, 8p |
| Abstrakt: |
A high-performance liquid chromatography (HPLC) method for assay of d-Lys6-GnRH contained in a microemulsion-type formulation is described. The peptide is extracted from the microemulsion matrix and quantified using a two-step gradient method. Separation from microemulsion compounds and potential peptide oxidation products was achieved on a Jupiter C18 column at 40°C, using a gradient of 10-35% CH3CN for peptide elution. The correlation of peak intensity measured at 220 nm and peptide concentration was linear over the range 2.5-60 µg/mL with a correlation coefficient of 0.9997 and a y-intercept not significantly different from zero ( p > 0.05). Intraday and interday variability of the assay was less than 5% for multiple injections of samples containing 7.5, 30 and 60 µg/mL. The lower limit of quantitation was calculated to be 0.38 µg/mL, and the lower limit of detection was 0.13 µg/mL. The assay was applied to samples that were stressed under physiological conditions (37°C, pH 7.4) over 4 days. Three degradation peaks were well resolved from the parent peptide, demonstrating the selectivity of the assay. Off-line MALDI TOF mass spectrometry was applied to identify these degradation species as oxidation products of the peptide. Copyright © 2009 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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