Chromatographic modeling of the release of particle-adsorbed molecules into synthetic alveolar surfactant.

Pseudophase liquid chromatography was used to measure the thermodynamic parameters governing adsorption of organic molecules from the surfaces of carbonaceous particles into liposomal zwitterionic mobile phases. These mobile phases contain many of the important physicochemical parameters of alveolar surfactant. Results show that physical desorption into model surfactant will be dependent upon the heat of solution and the heat of adsorption. Dominance of either thermodynamic parameter is dependent upon the relative polarity of the adsorbent surface and the adsorbate molecule. It is postulated from data obtained from simple molecules containing relevant organic functional groups that physical desorption of environmental agents from the surfaces of particulate complexes into alveolar surfactant may be predicted both by quantification of the polarity of the system and of the extent of surface coverage under investigation.