We present a set of electrical conductivity measurements of a mesoscopic equilibrium cluster phase in the aggregation process of charged particles induced by oppositely charged polyions. These measurements supply strong experimental evidence that correlated adsorption of polyions is driven by the counterion release. This phenomenon, known to occur in DNA-liposome mixtures in lamellar phase, i.e., when liposomes fuse together to form a sandwichlike structure encompassing DNA chains, was not previously observed in aqueous suspension of clusters of intact liposomes stuck together by polyions to form reversible aggregates. A simple statistical model of the lateral correlation of polyions at the particle surface justifies quantitatively the observed behavior of the counterion release, as shown by electrical conductivity measurements.
Counterion release in overcharging of polyion-liposome complexes
Bordi F;Sennato S;
2006
Abstract
We present a set of electrical conductivity measurements of a mesoscopic equilibrium cluster phase in the aggregation process of charged particles induced by oppositely charged polyions. These measurements supply strong experimental evidence that correlated adsorption of polyions is driven by the counterion release. This phenomenon, known to occur in DNA-liposome mixtures in lamellar phase, i.e., when liposomes fuse together to form a sandwichlike structure encompassing DNA chains, was not previously observed in aqueous suspension of clusters of intact liposomes stuck together by polyions to form reversible aggregates. A simple statistical model of the lateral correlation of polyions at the particle surface justifies quantitatively the observed behavior of the counterion release, as shown by electrical conductivity measurements.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
