MANUAL AND AUTOMATED (ROBOTIC) HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHYMETHODS FOR THE DETERMINATION OF MYCOPHENOLIC-ACID AND ITS GLUCURONIDE CONJUGATE IN HUMAN PLASMA

A manual and an automated (Zymark PyTechnology robot) HPLC method for simultaneous determination of plasma mycophenolic acid (MPA) and its g lucuronide conjugate (MPAG) are described here. Both methods are repro ducible and accurate, and both are equivalent in all respects, includi ng quantification limits (MPA, 0.100 mu g/ml; MPAG, 4.00 mu g/ml), ran ge (using 0.05-0.5 mi of plasma: MPA, 0.0500-20.0 mu g/aliquot; MPAG, 2.00-200 mu g/aliquot), precision, and accuracy. MPA and MPAG were sta ble under the conditions used with both methods. Results from aliquots of paired control samples, analyzed by the manual method over three y ears at six analytical laboratories, showed excellent agreement in pre cision and accuracy.