Abstract

Plasticized free films of cellulose acetate (CA) alone and in combination with different concentrations of polyvinyl pyrrolidone (PVP) were prepared and evaluated for transermal use. Adaptation of mercury substrate method and incorporation of dibutyl phthalate [40% w/w of polymer(s)] yielded thin, uniform and flexible films. Tensile strength of films decreased with increase of PVP fraction in the film. Both water vapour transmission and drug diffusion through the free films followed zero order kinetics and decreased with increase in film thickness. Permeability of films increased with increasing PVP concentration and this may be due to leaching out of PVP fraction, which leads to improved porosity and permeability. Free films composed of CA:PVP (2:1) can be used as rate of controlling membranes for the development of Transdermal Drug Delivery Systems (TDDS) systems using a suitable drug reservoir.