Quantitative bottom up analysis of infliximab in serum using protein A purification and integrated μLC-electrospray
Anne J Kleinnijenhuis1, Martha Ingola1, Jan H Toersche1
1TNO Triskelion, Utrechtseweg 48, 3704 HE Zeist, The Netherlands.
Background:
TNO Triskelion has applied its general workflow for the development of quantitative LC-MS methods for proteins in biological matrices to the quantification of infliximab in rat serum using bottom up μLC-MS/MS. Results/methodology: The general workflow consists of sample purification, analyte processing and LC-MS analysis. In the development of a quantitative μLC-MS/MS method for infliximab in rat serum the analyte processing part and the LC-MS part were optimized, in order to meet the different sample requirements of μLC-MS as compared with UPLC-MS. Using the optimized μLC-MS/MS method the LOQ was 75 ng/ml.
Conclusion:
The present study showed that it is possible to gain sensitivity when going to smaller scale LC-MS (UPLC-MS to μLC-MS). Due to the combination of a modified sample preparation approach and the application of μLC-MS a lower LOQ could be achieved for infliximab compared with a previously developed UPLC-MS method.


