Laser engineered polymer thin films as drug delivery systems

This study is focused on the fabrication of thin films of hydroxypropyl methylcellulose (HPMC) and ethyl cellulose (EC) polymer blends impregnated with captopril via matrix assisted pulsed laser evaporation (MAPLE) for the design of transdermal patches. The laser engineered polymer blend: captopril films are evaluated for physicochemical characteristics such as film morphology, chemistry of the films surface, drug content, and in vivo animal irritancy and skin sensitivity studies. The morphological investigation of the MAPLE fabricated coatings, i.e., by atomic force microscopy reveals that the morphology and topography of the polymer: drug films may be tuned by adjusting the HPMC: EC ratio in the MAPLE target. In addition, by tuning the HPMC: EC ratio in the as-deposited MAPLE films, it is possible to adjust the drug release profile. The Fourier-transform infrared spectroscopy investigation showed no interaction between captopril and the polymers (HPMC: EC) used. The skin irritation studies carried out on rabbits, showed no noticeable skin reactions, thus pointing out the compatibility of captopril with both the polymer blend and with the skin. In addition, no skin sensitization was noted among the guinea pigs that were challenged with the MAPLE fabricated transdermal patches. To sum up, the application of matrix-assisted pulsed laser evaporation for the fabrication of hydrophilic: hydrophobic polymer blends shows that there is great potential for the development of transdermal drug delivery system of captopril.