Palygorskite polypyrrole nanocomposite: A new platform for electrically tunable drug delivery

• The Pal PPy nanocomposite was facilely prepared without colloid templates.
• The drug-delivery system highly enhanced aspirin loading capacity compared with PPy.
• The drug-delivery system can be modulated easily by an external electrical stimulus.

A clay polymer nanocomposite (CPN) based on aspirin-loaded palygorskite (Pal) modified polypyrrole (PPy) was prepared by in situ electropolymerization of pyrrole monomer in the presence of Pal as the modifier and aspirin as the drug source. This drug-loading approach was simple and convenient, since colloid templates such as polystyrene microspheres used in conventional drug-loading system were not needed. The resulting CPN was characterized by TEM, XRD, cyclic voltammetry (CV), chronocoulometry, electrochemical impedance spectroscopy (EIS) and FTIR. The CPN was used as a new platform for aspirin delivery, which could significantly enhance aspirin loading capacity of the system and control aspirin release by external electrical stimulus. The results indicated that the proposed novel drug-delivery system might be promising as an implantable device where drug release could be electrically tuned according to the patient's requirement.