Composite porous biopolymer multilayer films as potential controlled delivery systems for tolfenamic acid

Abstract The aim of this paper is to investigate the potential of composite porous biopolymer films, created by lyophilization of solutions of two different biopolymers (Poly-D-lactic acid/PLA and Poly-ɛ-caprolactone/PEC) at different mass ratios (pure PLA, 3-to-1, 1-to-1, 1-to-3 and pure PEC), for controlled release of a chosen bioactive substance (tolfenamic acid). For this purpose, the prepared porous films were charged under corona discharge in a standard triode system (consisting of a charging electrode/needle supplied with 5 kV of a chosen polarity, a grid supplied with 1 kV with the same polarity as the charging electrode/needle and a grounded electrode) with positive charges. A set number of chitosan and casein multilayers were deposited on the surface of the charged porous films using a standard layer-by-layer (LbL) deposition technique, with the bioactive material being loaded in the casein layers. The drug release kinetics and the total amount of released drug in a standard dissolution medium were determined with the use of a spectrometer.