title: Permeation behavior of salbutamol sulfate through hydrophilic and hydrophobic membranes embedded by thermo-responsive cholesteryl oleyl carbonate.
abstract: OBJECTIVE
  To investigate the suitability of hydrophilic or hydrophobic membranes for use as potential thermo-responsive drug delivery system.
  
  
  METHODS
  Liquid crystal was embedded in membranes using vacuum filtration method to control the penetration rate of salbutamol sulfate. Cholesteryl oleyl carbonate (COC) with smectic-cholesteric phase transition temperature near 18 degrees C was used as a model liquid crystal.
  
  
  RESULTS
  It indicates only hydrophilic salbutamol sulfate can penetrate through the hydrophilic membranes embedded with or without COC, in which the permeation is mainly governed by the adsorption of COC. However, the hydrophilic drug do not pass through the hydrophobic membranes even if not embedded with COC. The void volume of the membrane also influences the penetration of salbutamol sulfate. The higher thermo-response efficacy of the COC-embedded membranes can be explained not only by less permeability through matrix part of the membrane but also by higher thermal motion of the COC molecules due to above the phase transition temperature.
  
  
  CONCLUSIONS
  A COC-embedded membrane with rate-controlled and thermo-responsive function is easily prepared by vacuum filtration method. High reversibly thermo-responsive function can be achieved by choosing membrane and COC concentration properly.
authors.affiliation: Department of Medical Research and Education, Veterans General Hospital-Taipei, Taiwan, Republic of China.
authors.forename: S Y
authors.initials: SY
authors.lastname: Lin
authors.forename: Y Y
authors.initials: YY
authors.lastname: Lin
authors.forename: K S
authors.initials: KS
authors.lastname: Chen
mesh_terms: D000420:Albuterol / Q000737:chemistry*; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D002788:Cholesterol Esters / Q000737:chemistry*; D006358:Hot Temperature; D007700:Kinetics; D008567:Membranes, Artificial; D008855:Microscopy, Electron, Scanning; D010539:Permeability; D013696:Temperature
chemical_list: D002788:Cholesterol Esters; D008567:Membranes, Artificial; D000420:Albuterol