Bottom-up sample preparation for the LC–MS/MS quantification of anti-cancer monoclonal antibodies in bio matrices

Abstract

Therapeutic monoclonal antibodies (mAbs) are rapidly taking over the treatment of many malignancies, and an astonishing number of mAbs is in development. This causes a high demand for quantification of mAbs in biomatrices both for measuring therapeutic mAb concentrations and to support pharmacokinetics and pharmacodynamics studies. Conventionally, ligand-binding assays are used for these purposes, but LC–MS is gaining popularity. Although intact (top-down) and subunit (middle-down) mAb quantification is reported, signature peptide (bottom-up) quantification is currently most advantageous. This review provides an overview of the reported bottom-up mAb quantification methods in biomatrices as well as general recommendations regarding signature peptide and internal standard selection, reagent use and optimization of digestion in bottom-up quantification methods.