Electroconductive nanocomposite hydrogel for pulsatile drug release

Polyacrylamide (PAAm) hydrogel containing nanofibers of polyaniline (PANI) has been prepared in order to evaluate it as electric stimuli-responsive material. Amoxicillin was loaded onto chemically synthesized PANI nanofibers of large-aspect-ratio. Composite hydrogel was obtained by the in situ incorporation of amoxicillin-loaded PANI during polymerization and reticulation of acrylamide. TEM images of cross sections of PAAm/amoxicillin-loaded PANI composite revealed a continuous 3D nanofiber network of PANI supported by the hydrogel matrix. The antibiotic molecules were accurately released (or sustained) from composite hydrogel in response to application (or removal) of cathodic electrical stimulation. In vitro cytotoxicity evaluation of composite hydrogel extract on mouse subcutaneous connective tissue has shown cell viability higher than 80%. The tuning release profile and minimal toxicity of the material evidenced its potential for electrically controlled drug delivery applications such as implantable devices and transdermal drug delivery systems.