Methods to detect, characterize, and quantitate biological samples after administration of antibody conjugates, antibody-drug conjugates of Formula I, antibodies, and fragments and metabolites thereof, by immunoaffinity bead separation, chromatography, and mass spectrometry are disclosedAb-(L-D)p IwhereinAb is an antibodyD is a drug moietyL is a linker covalently attached to Ab, and covalently attached to D andp is 1, 2, 3, 4, 5, 6, 7, or 8.
