This post was transferred manually from the old version of MolMeth to the new one.
I got this advice from Paolo Cifani in Lund Since the sample is frozen I would grind it in liquid nitrogen (with pestle and mortar) and try to extract protein with, for example, RIPA buffer. This should work for gel/antibody based application but could give trouble to the LC-MS because of the detergents in the RIPA buffer. In this case you can try replacing NP-40, SDS and DOC in the RIPA buffer with a labile detergent like Rapigest. But it really depends on what you are trying to achieve with your sample extraction. Are there any specific proteins you are looking for or is this some kind of pre-analytic step?