ION DRIVE FOR VESICLES AND CELLS

Non-uniform ion pumping across the bounding membrane of a biological c ell or artificial vesicle can generate electro-osmotic effects. Self-p ropulsion of cells at speeds of up to several microns per second is po ssible. Viscous stresses are generated that lead to significant distor tion for a membrane lacking considerable reinforcement by, for example , a cytoskeleton, even if immobilized by adhesion to a substrate. A re lation between magnitudes of self-induced effects and the measured ele ctrophoretic mobility is shown. (C) 1996 Academic Press Limited