The nature of the cell membrane charge measured by partition in aqueous two-polymer phase systems: Differentiation of classes of beef erythrocytes

Interaction of neutral polysaccharides with phosphatidylcholine multilamellar liposomes. Phase transitions studied by the binding of fluorescein-conjugated dextrans

“…It is known that neutral polysaccharides can interact with cell membranes and induce cell aggregation (Brooks & Seaman, 1972;Brooks, 1973; Jan & Chien, 1973;Minetti et al, 1976). Cell surface interaction with neutral polymer has been used to separate cell populations (Uhlenbruck et al, 1967;Walter et al, 1972).…”

Separation of Erythromycin-Resistant and -Susceptible Subpopulations of Escherichia coli 15 by Partition in Two-Polymer Aqueous Phases

“…Because of this, one of the major determinants of cell partition in two-polymer aqueous phases is surface charge (7,21). The charge measured by the phases is not necessarily the same as that measured by cell electrophoresis, because the latter reflects only the charge effective at the plane of shear, whereas the former measures charge much deeper into the cell wall or membrane (22). Partition, which is an extremely sensitive indicator of surface charge-associated properties (2), has been applied, in the current report, to the detection and differentiation of antibioticsusceptible and -resistant subpopulations of E. coli 15.…”

“…Subtle differences or changes in cell surface properties (particularly surface charge) can often be detected by a concomitant difference or change in partition. Thus, in the case of mammalian cells, red blood cells have been separated into populations of different ages (20) and erythrocytes have been segregated from white cells (19) and white cells from each other (17); bone marrow cell populations have been subfractionated (18) [15][16][17][18][19][20][21][22][23][24][25][26].…”

Negative Surface Charge on Platelets of Patients with Idiopathic Scoliosis

“…The two-phase polymer partition system is considered to be a most sensitive indicator of certain properties of cellular surface mem branes [6][7][8], With the solutions used here the high ratio of phosphate to chloride ions generated an electrostatic potential difference between the phases. The surface negative charge of the platelets interacts with the par tition potential and produces a characteristic distribution of the cells between the phases.…”

“…The two-phase aqueous polymer separation sys tem was used to measure the proportions of platelets with high and low negative charge [6][7][8], Platelets treated with cationised ferri tin were used to measure the surface anionic sites [9].…”