Purification of Plasma Membranes by Affinity Partitioning

This chapter describes the purification of rat liver plasma membranes by affinity partitioning in an aqueous polymer two-phase system using the lectin wheat germ agglutinin (WGA) as affinity ligand. Affinity partitioning is advantageous for conventional membrane fractionation techniques in being highly selective, allowing the rapid and high-yield purification of membranes. In addition, the aqueous polymer environment is gentle to membrane structure and function.