Effect of a second solubilizate on the partition coefficient of drugs in micellar solution and their permeation rate across an artificial membrane.
The distribution of a solubilizate between micelles and the aqueous phase does not obey a simple partition law when a second solubilizate species is present. Alterations of the apparent partition coefficient cannot be explained in terms of a simple displacement mechanism, following the interaction of both solubilizates with the same site of the micelle. A non linear increase in solubilizate association to micelles following an increase in surfactant concentration is observed in the presence of a second solubilizate. A depression in the cloud point temperature follows the addition of a second species and is such that cannot be interpreted as a simple additive effect. Alteration of the apparent partition coefficient in a miscellar solution has an effect on the permeation rate of the solubilizate across an artificial membrane. Biopharmaceutical implications are discussed.
D001565:Benzoates / Q000378:metabolism; D002701:Chloramphenicol / Q000378:metabolism; D003102:Colloids; D003956:Dialysis; D008567:Membranes, Artificial; D008823:Micelles; D009268:Nalidixic Acid / Q000378:metabolism; D009994:Osmolar Concentration; D010539:Permeability; D004364:Pharmaceutical Preparations / Q000378:metabolism*; D011136:Polysorbates; D012995:Solubility; D013997:Time Factors
D001565:Benzoates; D003102:Colloids; D008567:Membranes, Artificial; D008823:Micelles; D004364:Pharmaceutical Preparations; D011136:Polysorbates; D009268:Nalidixic Acid; D002701:Chloramphenicol