Monitoring the simultaneous ostwald ripening and solubilization of emulsions.

The simultaneous Ostwald ripening of an emulsion and the solubilization of its oil droplets by added micellar surfactant solutions are monitored by measurements of time-averaged scattered intensities. A simple computer simulation model for the interpretation of the measurements is presented. Experimental data are analyzed with this model using one single parameter: an effective ratio of oil to surfactant molecules involved in the withdrawal of oil from the Ostwald ripening process by the added micelles.

Physico-chemical characterization of a double long-chain cationic amphiphile (Vectamidine) by microelectrophoresis.

We recently synthesized a novel cationic amphiphile (N-t-butyl-N'-tetradecyl-3-tetradecylaminopropionamidine or Vectamidine (previously described as diC14-amidine)) that associates with DNA and RNA and facilitates their entry and expression into eukaryotic cells. Among several parameters that have been shown to influence the transfection process, the surface charge density plays a key role. Quantitative information about that charge density associated to the cationic amphiphiles organized in liposomal structure is not yet available.