Abstract
The design of new interpolyelectrolyte complexes (IPEC) between Eudragit® polycation (type RL) and oppositely charged Eudragit® polyanions (types L100-55, L100, S100, FS) was investigated. The formation and chemical composition of novel IPECs between countercharged Eudragit® copolymers was established by gravimetric and elemental analysis. The structure and solid state properties of the synthesized IPEC were investigated comparatively to correspondent physical mixtures pairs of copolymers in similar molar ratio, using Fourier transform infrared (FTIR) spectroscopy and modulated temperature differential scanning calorimetry (mDSC). The binding ratio of a unit molecule of RL with polyanions was found to range between 1.73:1 and 4.19:1 while increasing the percentages of carboxylic groups in their structures from 10% (FS) to 50% (L100-55). As a result of electrostatic interaction between the copolymer chains, the glass transition temperature of the IPEC changed significantly. Considerable pH-sensitive swelling in acidic and neutral media was observed for different type of IPECs. Through evaluation of diffusion-transportation properties of the IPECs, basic mechanisms controlling the delivery of indomethacin were obtained. The results of swelling and release of the model drug from the polycomplex matrices confirm that they have potential to be used in colon-specific drug delivery.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have