PURIFICATION OF PROTEINS BY THE USE OF HYDROPHOBIC ZEOLITE-Y

Hydrophobic zeolite Y can be used as a fast and efficient and inexpens ive matrix in the purification of proteins from crude extracts. Prefer ably the zeolite can be used in the first purification step, replacing the commonly used precipitation techniques with (NH4)(2)SO4 or ethano l. The time required for the zeolite prefractionation was a few hours compared to the much more time consuming precipitation procedure which demands centrifugation and subsequent dialysis. Proteins can be adsor bed on the zeolite either in order to remove undesired proteins or to be subsequently eluted from the zeolite in order to achieve purificati on and concentration. Removal of undesired proteins is exemplified by the purification of horseradish peroxidase from a crude extract. The z eolite procedure enhanced the specific activity five times and provide d a yield similar to that which was obtained by the use of standard pr ocedures, (NH4)(2)SO4 fractionation and ion-exchange chromatography. B inding and subsequent elution of proteins from the zeolite is exemplif ied by the purification of monoclonal antibodies from hybridoma cultur e supernatants. Proteins were desorbed from the zeolite by the use of polyethylene glycol 600 and this procedure yielded a purification fact or of 5. (C) 1994 Academic Press, Inc.