TY - JOUR T1 - Simultaneous determination of cortisol, dexamethasone, methylprednisolone, prednisone, prednisolone, mycophenolic acid and mycophenolic acid glucuronide in human plasma utilizing liquid chromatography-tandem mass spectrometry. AU - Difrancesco,Robin, AU - Frerichs,Valerie, AU - Donnelly,Julie, AU - Hagler,Colleen, AU - Hochreiter,Jill, AU - Tornatore,Kathleen M, Y1 - 2007/09/14/ PY - 2007/04/05/received PY - 2007/08/28/revised PY - 2007/09/02/accepted PY - 2007/10/12/pubmed PY - 2008/1/31/medline PY - 2007/10/12/entrez SP - 42 EP - 51 JF - Journal of chromatography. B, Analytical technologies in the biomedical and life sciences JO - J Chromatogr B Analyt Technol Biomed Life Sci VL - 859 IS - 1 N2 - Chronic combination immunosuppressive regimens are commonly prescribed to renal transplant recipients. To develop an assay method for pharmacokinetic studies and therapeutic drug monitoring of multiple immunosuppressives, a liquid chromatography-tandem mass spectrometry (LC/MS/MS) approach for the simultaneous analysis of several glucocorticoids, mycophenolic acid (MPA) and mycophenolic acid glucuronide (MPAG) was investigated. The resultant method utilized a gradient reverse phase separation over a Symmetry C18 column using an ammonium acetate-methanol mobile phase at pH 3.5. The analytes were detected by coupling the chromatography system via electrospray to a triple quadrupole mass spectrometer. Multiple-reaction monitoring in the negative mode ion (MH-/product) was employed selecting MPA at 319.1/190.9, MPAG at 495.1/191.0, dexamethasone at 391.0/361.0, hydrocortisone at 361.1/331.1, methylprednisolone at 373.1/343.1, prednisone at 357.1/327.2, and prednisolone at 359.1/329.1. The calibration curve concentrations ranged from 3.60 ng/mL to 50 microg/mL with the lowest limit of quantitation for corticosteroids being 3.60-7.20 ng/mL and 0.656-6.75 microg/mL for MPA and MPAG, respectively. The relative standard deviation for quality control intraday variation and interday variation was between 0.76% and 9.57% for all analytes. This assay offers a versatile, unique method for multi-analyte immunosuppressive determinations during combination immunosuppression. SN - 1570-0232 UR - https://www.unboundmedicine.com/medline/citation/17928278/Simultaneous_determination_of_cortisol_dexamethasone_methylprednisolone_prednisone_prednisolone_mycophenolic_acid_and_mycophenolic_acid_glucuronide_in_human_plasma_utilizing_liquid_chromatography_tandem_mass_spectrometry_ L2 - https://linkinghub.elsevier.com/retrieve/pii/S1570-0232(07)00645-9 DB - PRIME DP - Unbound Medicine ER -