Influence of chlorhexidine species on the liquid crystalline structure of vehicle

The aim of this study was to investigate the influence of three chlorhexidi ne species, chlorhexidine base and its salts (diacetate and digluconate), o n the physico-chemical features of liquid crystalline systems and on drug t ransport through lipophilic membranes. Nonionic surfactant, Synperonic A7 ( PEG(7)-C13-15) was selected for the preparation of the liquid crystalline s ystems. Mixtures of different ratios of Synperonic A7 and water were prepar ed. The liquid crystalline systems were characterized using polarizing micr oscopy, small-angle neutron scattering and transmission electron microscopy . Membrane transport was also examined. The addition of chlorhexidine speci es to the liquid crystalline system modified the structure of the liquid cr ystalline system. As a result of liquid crystal-drug interaction, the solub ility of chlorhexidine base and its diffusion through lipophilic membranes increased in comparison with those of the chlorhexidine salts. (C) 2001 Els evier Science B.V. All rights reserved.