34. An LC-MS/MS Method for Simultaneous Analysis of Cyclosporin A and Tacrolimus in a Transplant Population and Comparison with the Abbott IMx and AxSYM, Respectively
Poster: Tue 6:30-7:30PM
Marguerite MacMahon
Mater Misericordiae University Hospital
View Long Abstract
A combined Cyclosporin A (CsA) and Tacrolimus method was evaluated using a Waters Acquity TQD and compared to Abbott AxSYM and IMx immunoassay systems. Interassay imprecision was found to be 3.0 & 3.9% and intraassay imprecision 5.7 & 4.5% for CsA and Tacrolimus respectively. Linearity ranged from 10-1500ng/ml for CsA and 1-30ng/ml for Tacrolimus. Analysis of patient samples showed and overall negative bias for CsA using LC-MS/MS of 20% when compared with the immunoassay method. Investigation of International Proficiency Testing Scheme samples demonstrated excellent correlation (r2 =0.999 CsA & r2=0.998 Tacrolimus) with the assigned group means. LC-MS/MS was deemed a highly specific and sensitive method of immunosuppressant determination.