Patent ID: 8012693

Claim:
A method of analyzing analytes, the method comprising: providing a cellular sample comprising chemically crosslinked analytes, wherein the sample is one or more formalin-fixed, paraffin-embedded tissue sections, and wherein the analytes are proteins or peptides or combinations thereof; separating the chemically crosslinked analytes from the formalin-fixed, paraffin-embedded tissue sections by heat; reversing at least a portion of the chemical crosslinks in the crosslinked analytes and forming decrosslinked analytes, wherein said reversing at least a portion of the chemical crosslinks comprises cleaving at least a portion of the chemical crosslinks, with the proviso that substantially no naturally occurring bonds in the analytes are cleaved during said reversing at least a portion of the chemical crosslinks; and analyzing the analytes by analyzing the decrosslinked analytes using mass spectrometry.