The invention uses liquid chromatography-mass spectrometry to verify the presence or absence of the extractables introduced into a biopharmaceutical product during manufacture, filtration or storage at above a certain concentration. The method disclosed herein can be used to detect the presence of extractables in the actual biopharmaceutical product rather than a surrogate solvent system. Detection of the extractables in the actual drug product provides an accurate description of the leachables profile likely to be introduced to the human or animal patient. In one embodiment, the extractable are introduced by filtration of the bio-pharmaceutical product.