High surface area polypyrrole scaffolds for tunable drug delivery

Int J Pharm. 2013 Feb 25;443(1-2):163-8. doi: 10.1016/j.ijpharm.2013.01.006. Epub 2013 Jan 11.


Intrinsically conducting polymers such as polypyrrole (PPy) are viable platforms for efficient drug delivery, where release rates can be tuned by external electrical stimulus. In this study, the successful fabrication of 3-dimensionally ordered macroporous PPy inverse opal thin films is described, and the viability of such films for controlled drug release evaluated in vitro. The PPy inverse opal thin films were obtained by electropolymerization of PPy through the interstitial voids of a colloidal crystal template composed of poly(methyl methacrylate) colloids of diameter ∼430 nm. Chemical etching of the template yielded macroporous PPy inverse opal scaffolds. The model drug risperidone was loaded into the PPy inverse opal films, and then entrapped by electropolymerization of a non-porous PPy overlayer. The morphology and chemical composition of the PPy scaffolds were evaluated by SEM and FTIR spectroscopy, respectively. The high surface area PPy inverse opal scaffolds exhibited enhanced drug loading and releasing capabilities compared to conventional non-porous PPy films. Drug release profiles could be modified by applying electrical stimulus, which caused actuation of the porous polypyrrole films. The proposed delivery system may find use as an implantable device where drug release can be electrically tuned according to patient requirements.

MeSH terms

  • Antipsychotic Agents / administration & dosage*
  • Colloids
  • Crystallization
  • Drug Carriers / chemistry*
  • Drug Compounding
  • Drug Delivery Systems / instrumentation
  • Drug Delivery Systems / methods
  • Electric Stimulation
  • Electrodes
  • Microscopy, Electron, Scanning
  • Models, Structural
  • Polymers / chemistry*
  • Polymethyl Methacrylate / chemistry
  • Porosity
  • Pyrroles / chemistry*
  • Risperidone / administration & dosage*
  • Spectroscopy, Fourier Transform Infrared
  • Surface Properties


  • Antipsychotic Agents
  • Colloids
  • Drug Carriers
  • Polymers
  • Pyrroles
  • polypyrrole
  • Polymethyl Methacrylate
  • Risperidone