Preparation of cytosol for steroid receptor determinations with the Beckman "Airfuge".

Preparation of cytosols from several estrogen target organs was compared, with use of the Beckman Airfuge and a preparative ultracentrifuge. The specific estrogen-binding capacities of cytosols prepared with these instruments were indistinguishable. Similarly, the sedimentation profiles of estrogen-receptor species as determined by sucrose gradient centrifugation were identical. We conclude that the Airfuge provides a rapid, accurate, and inexpensive means of preparing cytosols for measurements of steroid receptors in the clinical laboratory.