The focus of this chapter is on bio-intended procedures based on mixing surfactants with polymers and biopolymers, or surfactants among them (provided they are oppositely charged). In the first case, polymer-surfactant and protein-surfactant systems are dealt with. Both are characterized by the splitting of the solution phase into, at least, three regions having peculiar properties. At first, surfactant nucleation onto polymers takes place; this implies large modifications in properties with respect to the starting materials. The formation of gels is possible in some instances. As to mixtures of oppositely charged surfactants, it is indicated how they form cat-anionic vesicles if mixed in nonstoichiometric amounts. Vesicle sizes are modulated by the charge ratio. These systems are excellent vectors for biomedical purposes.
Part of the book: Surfactants and Detergents
It is common to entities having sizes in the nano/micro-scale range be that, real or bio-intended systems, to undergo the action of many different forces, imparting them colloid stability. Ubiquitary electrostatic contributions, sometimes dominant, may overlap with steric stabilization ones; their combination effectively takes place in most cases. The two effects are jointly responsible, for instance, for the control of many phenomena such as: adhesion onto cells of alien agents, cellular separation during morpho-functional evolution, uptake of exogenous materials into cells and tissues. We evidence here, how the combination of these forces operates, and indicate the procedures leading to their effectiveness, when required for purposes inherent to biomimicry.
Part of the book: Colloid Science in Pharmaceutical Nanotechnology