Establishment of a Liquid Chromatography-Tandem Mass Spectrometry Method for the Determination of Immunosuppressant Levels in the Peripheral Blood Mononuclear Cells of Chinese Renal Transplant Recipients

Background: Monitoring immunosuppressant levels, such as mycophenolic acid (MPA), cyclosporin A (CsA), and tacrolimus (TAC), in peripheral blood mononuclear cells (PBMCs) could be useful in organ transplant patients administered individualized therapy. The authors developed a liquid chromatography-tandem mass spectrometry assay technique to simultaneously determine immunosuppressant levels in PBMCs and assess their pharmacokinetics in Chinese renal allograft recipients. Methods: PBMCs were isolated from the whole blood of 27 Chinese renal transplant patients using Ficoll-Paque Plus solution, and cell number was determined; acetonitrile treatment for protein precipitation, and gradient elution was performed on an Agilent Eclipse XDB-C18 column (3.5 μm, 2.1 × 100 mm) with mobile phase: water and methanol (containing 2 mM ammonium formate); flow rate: 0.3 mL·min−1. Results: The calibration curves of MPA, CsA, and TAC had a linear range (ng·mL−1): 0.098–39.2 (r = 0.9987), 0.255–102 (r = 0.9969), and 0.028–11.2 (r = 0.9993), respectively. The extraction effects, matrix effects, and mean relative recovery of these immunosuppressants were 70.4%–93.2%, 72.7%–96.5%, and 90.1%–112.4%, respectively. The within-day and between-day coefficients of variation were
Source: Therapeutic Drug Monitoring - Category: Drugs & Pharmacology Tags: Original Article Source Type: research