Solubility and permeability of steroids in water in the presence of potassium halides.
Water forms a network of hydrogen bonded water molecules that gives liquid water unique physicochemical properties. Ions that affect the network structure, e.g. potassium halides, are known to either increase or decrease aqueous solubilities of drugs. Most biological membranes consist of hydrophilic exterior and a lipophilic interior. Mathematically they can be treated as two-layer membranes, i.e. a hydrophilic water layer that is referred to as unstirred water layer (UWL) and a lipophilic membrane. The purpose of this study was to investigate if and then how ions affect drug permeation through the UWL. The effects of potassium halides on the solubility and permeability of dexamethasone and hydrocortisone was investigated. The potassium halides had either increasing or decreasing effect on their aqueous solubility but did not have any effect on their permeability through UWL.
Faculty of Pharmaceutical Sciences, University of Iceland, Reykjavik, Iceland.
M
M
Messner
T
T
Loftsson
D000893:Anti-Inflammatory Agents / Q000008:administration & dosage / Q000737:chemistry; D002476:Cellophane; D002851:Chromatography, High Pressure Liquid; D003907:Dexamethasone / Q000008:administration & dosage / Q000737:chemistry; D006219:Halogens / Q000737:chemistry*; D006854:Hydrocortisone / Q000008:administration & dosage / Q000737:chemistry; D008055:Lipids / Q000737:chemistry; D008567:Membranes, Artificial; D010539:Permeability; D017680:Potassium Compounds / Q000737:chemistry*; D012995:Solubility; D013056:Spectrophotometry, Ultraviolet; D013256:Steroids / Q000008:administration & dosage / Q000737:chemistry*; D014867:Water
D000893:Anti-Inflammatory Agents; D006219:Halogens; D008055:Lipids; D008567:Membranes, Artificial; D017680:Potassium Compounds; D013256:Steroids; D014867:Water; D003907:Dexamethasone; D002476:Cellophane; D006854:Hydrocortisone