Evaluation of Blood Lysis Procedures prior to Automated Sample Preparation for Immunosuppressant Assay by LC-MS/MS

CLAM-2000 (Shimadzu Corp., Japan) fully automates blood or other samples pre-treatment prior to LC-MS analysis. The whole blood has cell debris, fibrin clots and so on. It is desirable to remove such particulates for accurate sample dispensing by centrifugation. However, this poses a challenge to the measurement of immunosuppressants (ISP) in whole blood samples since large proportion of ISP are bound to cytoplasmic proteins in erythrocytes1). Thus, it is mandatory to release erythrocytes prior to any centrifugation of the blood. Current practice is to freeze and thaw samples, which is not convenient for emergency analysis. To address this, several protocols of hemolysis were tested. Evaluation of the protocol was based on lysis efficiency, immunosuppressant recovery and time consumption.