DRUG PERMEATION THROUGH A TEMPERATURE-SENSITIVE POLY(N-ISOPROPYLACRYLAMIDE) GRAFTED POLY(VINYLIDENE FLUORIDE) MEMBRANE

Poly(N-isopropylacrylamide) (poly(NIPAAm)) is a temperature sensitive polymer, which has been used in the development of thermally controlle d devices. In the present study, poly(NIPAA)m grafted poly(vinylidene fluoride) (PVDF) membranes were prepared by an irradiation method and fluxes of model compounds across the various grafted membranes were me asured. The effectiveness of various grafted membranes to control drug fluxes by temperature was studied using FITC-dextrans (molecular weig hts 4400-50 600) and mannitol as model compounds. Also, the effect of environmental conditions on the LCST of the membrane was evaluated. Th e fluxes of bigger molecules across a temperature sensitive, porous po ly(NIPAA)m-PVDF membranes were effectively controlled by temperature, environmental ionic strength and degree of grafting of the membrane, w hile flux of the smaller molecules was not controlled thermally even a t high degree of membrane grafting. These result indicates that the st udied membranes are useful in controlling the permeation of high molec ular weight compounds such as polynucleotides, peptides and proteins. (C) 1998 Elsevier Science B.V. All rights reserved.