Corticosteroids immunoaffinity chromatography

C. S. Creaser, S. J. Feely, E. Houghton and M. Seymour, Immunoaffinity chromatography combined on-line with high performance liquid chromatography-mass spectrometry for the determination of corticosteroids , 7. Chromatogr. 794 37-43 (1998). 

Following solid-phase extraction, all extracts are adjusted in the pH range 7-7.5, and submitted to additional cleanup on an immunoaffinity column containing a mixture of dexamethasone- and prednisolone-specific gels. Column washing is performed with water, while elution of the analytes with 3 ml methanol/water (80 20). Aliquots of the eluates are submitted to oxidative reaction with pyridin-ium chlorochromate, and the oxidized corticosteroid derivatives are then analyzed by gas chromatography-mass spectrometry under the conditions shown in Table... 

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