Nanocomposite hydrogels of gellan gum and polypyrrole for electro-stimulated ibuprofen release application

The development of stimuli-responsive release systems as functional platforms for controlled drug delivery is a valuable contribution to modern-day medical practice. In this work, novel electroactive nanocomposite hydrogels were prepared by encapsulating green-synthesized polypyrrole (PPy) colloids within bioamine-crosslinked gellan gum (GG) networks. The structural, physicochemical, and morphological properties of GG/PPy hydrogels were studied by Fourier transform infrared spectroscopy, thermogravimetry, rheological analysis, scanning electron microscopy, and swelling kinetic measurements. The hydrogels exhibited an interconnected porous structure with undefined boundaries. Viscoelastic properties and swelling behavior of materials were dependent on their filler content. In vitro ibuprofen (IBP) release studies from hydrogels were carried out without and under different electrical stimulations. The IBP release kinetic from GG/PPy hydrogels was remarkably activated by electrical stimuli. A unique pulse potential of 5 V increased the drug delivery up to 63% from nanocomposite hydrogel, in contrast to the low IBP amount released in a passive form (10%). The PPy reduction played a determining role as the main driving force in drug release activation. The tuning release profiles evidenced the potential of materials for electrically controlled drug delivery in implantable or transdermal drug release devices.