An improved method for the isolation of surface membranes from cells in monolayer culture.

A modification of the procedure reported by Scher and Barland (Biochim. Biophys. Acta 255 (1972) 580-588) for the isolation of the surface membranes of cells grown in monolayer culture is described. The modification involves addition of a purification step utilizing the two-phase polymer system described by Brunette and Till (J. Membr. Biol. 5 (1971) 215-224). The modified method permits the isolation of surface membranes from cells not yet at confluence, when they may easily become detached from the substratum.