Introduction of nanoparticles can modify electrical properties such as the permittivity and conductivity of a medium. This model based study focuses on such modulated changes of an extracellular medium from the standpoint of enhancing electroporation to achieve more efficient delivery into biological cells. A finite element, time-dependent axisymmetric bio-model, coupled with the Smoluchowski equation, has been used to evaluate the transmembrane potentials and evolution of pore densities. Our simulation results show that a relatively small fraction of gold nanoparticles in the extracellular medium effectively enhances the transmembrane potentials, leads to much higher pore densities, and shifts the pore distribution towards larger radii. This collectively bodes well for enhancing drug delivery or gene transfection in cells.