Wang C.-Y.Hsieh H.-J.Chu C.-Y.Wang D.-M.2019-05-032019-05-03200116090985https://scholars.lib.ntu.edu.tw/handle/123456789/406396A procedure was developed in the present work to calculate the effective diffusivity of drugs through polymeric membranes subject to swelling gradient. Experiments were also performed to examine the accuracy of the calculation procedure. The membranes used were dense polyurethane and poly(ethylene-co-vinylacetate) membranes, the model drug was benzocaine, and the swelling agent was ethanol. To calculate the effective diffusivity of benzocaine, it requires knowing the dependence of benzocaine diffusivity on ethanol concentration and the ethanol concentration profile across membrane. Experiments of homogeneous swelling were carried out to determine the relationship between benzocaine diffusivity and ethanol concentration. In addition, by measuring the ethanol fluxes corresponding to different ethanol concentrations in the donor cell, the ethanol concentration profile across membrane can be determined. With the above information, the effective diffusivity of benzocaine through membranes with swelling gradient can be calculated. Experiments were also carried out to measure the effective benzocaine diffusivity. Agreement between the calculated and experimental results was obtained, indicating that the proposed calculation procedure is quite reliable.DiffusionDrug transportPolymeric membraneSwellingSwelling gradientjournal article2-s2.0-0035707443https://www.scopus.com/inward/record.uri?eid=2-s2.0-0035707443&partnerID=40&md5=9e0c296ab00fc404b7b025ecf34d889c