Langmuir 2009, 25, 451-457
451
Electrical Pulsed Stimulation of Surfaces Homogeneously Coated with Gold Nanoparticles to Induce Neurite Outgrowth of PC12 Cells Ji Sun Park,† Kyeongsoon Park,‡ Hyun Tae Moon,§ Dae Gyun Woo,| Han Na Yang,† and Keun-Hong Park*,† College of Medicine, Pochon CHA UniVersity, CHA Stem Cell Institute 606-16, Yeoksam 1-dong, Kangnam-gu, Seoul 135-081, Republic of Korea, Biomedical Research Center, Korea Institute of Science and Technology, 39-1 Hawolgok-dong, Seongbuk-gu, Seoul 136-791, Republic of Korea, Mediplex Corp., 1204 ACE High-End Tower, 235-2, Guro-3-dong, Guro-gu, Seoul 152-711, Korea, and Chabiotech Co., Ltd., Yeoksam 1-dong, Kangnam-gu, Seoul 135-081, Republic of Korea ReceiVed August 7, 2008. ReVised Manuscript ReceiVed October 27, 2008 In this study, the potential of gold nanoparticles (20 nm) to deliver electrical stimulation to nerve cell cultures in Vitro to induce nerve regeneration was evaluated. In order to use these biomaterials to deliver an electrical stimulus, we devised a novel method for the fabrication of a nanostructured 2D substrate comprising gold nanoparticles attached to the surface of a cover glass via an adsorption system. In this strategy, gold nanoparticles are created and then coated onto a positively charged cover glass that has been pretreated with polyethyleneimine (PEI). Scanning electron microscopy (SEM) revealed that the PC 12 cells extended neurites well on the gold nanoparticles in the presence of electrical stimulation. In addition, the neurite outgrowth of PC12 cells in response to pulsed and constant electrical stimulation was evaluated by live/dead cell determination, by reverse transcriptase polymerase chain reaction (RT-PCR) analysis, as well as by β-tubulin and NF-200 expression. By electrical stimulation (250 mV for 1 h), PC12 cells with their neurite outgrowth length were highly increased, with a mean diameter of 98.5 µm. However, the neurite outgrowth length without electrical stimulation was approximately 10∼20 µm. Moreover, the alternating current stimulation also showed good viability (