THE EFFECT OF ADSORBED CHARGED POLYPEPTIDES ON THE ELECTROPHORETIC MOBILITY OF POSITIVELY AND NEGATIVELY CHARGED POLYSTYRENE LATTICES

Electrophoretic mobilities of negatively charged polystyrene particles that are covered with variable amounts of positively charged poly-L-lysine (of different molecular weights) and of positively charged polystyrene latices that have analogously been modified with negatively charged poly-L-glutamic acid are reported. Particles that are fully covered with oppositely charged polyelectrolyte exhibit a maximum in the electrophoretic mobility as a function of the ionic strength. This is an indication that the maxima in the zeta potential of untreated polystyrene lattices as a function of electrolyte concentration can possibly be ascribed to the presence of polyelectrolytes on these 'bare' particles as well.