Evaluations of dielectric property and drug release profile of 5-FU patches based on plasma charged electrets

In the present study, the electret 5-fluorouracil patch was developed, the effective surface potential, piezoelectric coefficient d₃₃, open-circuit thermally stimulated discharge (TSD) current spectra and shear adhesion of the patch were measured. The drug release profile of the patch was determined by using high performance liquid chromatography method. A stable potential difference which was positively dependent on the surface potential of the electret was generated on two sides of the patch. The measurements of d₃₃ coefficient, TSD current spectra and adhesion performance showed that the electrostatic field of the electret could cause polarization and cohesive strength decreasing of the matrix molecules, change the distribution and interaction of the drug molecules in patch, therefore to increase the release of drug from the transdermal patch.