The in situ colonic effective permeability of fluvastatin in the rat was found to be inversely proportional to the surface tension of fluvastatin. Furthermore, t 1/2 was related to the intrinsic viscosity of the polymers. The half-life of the surface tension (t 1/2) at these concentrations was found to be inversely correlated to the diffusion coefficient and to the square of the bulk concentration, which is expected for a diffusion process.

The time dependence of surface tension is mainly related to the concentration in the dynamic region (2-10 ppm). These parameters depend on the hydrophilic/hydrophobic balance of the polymer. The surface activity and the cloud point (CP) are related to each other. The surface tension measurements were performed by the pendant drop method. They show surface activity at very low concentrations which makes them useful as stabilizers in suspensions and emulsions. The investigated polymers are more or less surface active due to the presence of hydrophilic and hydrophobic parts. Polymers display a very wide diversity of properties which makes a detailed characterization necessary.

Many of them are derived from cellulose but there are several biological sources of importance for their production. Polymers are important in a variety of pharmaceutical applications. 1999 (English) Doctoral thesis, comprehensive summary (Other academic) Abstract

Half life surface tension