Surface modification of neural probes with conducting polymer poly(hydroxymethylated-3,4- ethylenedioxythiophene) and its biocompatibility.

Abstract

A novel conducting polymer, poly(hydroxymethylated-3,4-ethylenedioxythiophene) (PEDOT-MeOH), was electrochemically deposited onto the electrodes of micromachined neural probes. Uniformly distributed film was obtained from aqueous solution when doped with polystyrenesulfonate. The surface morphology was rough and had good cellular adhesion. Impedance spectroscopy showed that the magnitude of coated electrode was lower than that of the bare gold over a range of frequencies from 10(0)to 10(5) Hz. Since the biocompatibility of the interface between the neural probes and brain tissue plays an important role when the probes are implanted in the central nervous system for long-term application, biomolecules were incorporated into the coating. Nonapeptide CDPGYIGSR was codeposited as the counterion in the conducting films. The surface morphology of the coating was fuzzy, providing many bioactive sites for interaction with neural cells. The magnitude of impedance was as low as 53 kOmega at the biologically relevant frequency of 1 kHz. An in vitro experiment demonstrated that the neuroblastoma cells grew preferentially on the PEDOT-MeOH/CDPGYIGSR-coated electrode sites and spread beyond the electrode area.

• Authors: Yinghong Xiao, David C Martin, Xinyan Cui, Mahesh Shenai
• Journal: Applied biochemistry and biotechnology (Appl Biochem Biotechnol) Vol. 128 Issue 2 Pg. 117-30 (Feb 2006) ISSN: 0273-2289 [Print] United States
• PMID: 16484721 (Publication Type: Journal Article, Research Support, N.I.H., Extramural, Research Support, Non-U.S. Gov't)

Chemical References

• Bridged Bicyclo Compounds, Heterocyclic
• Laminin
• Peptides
• Polymers
• Polystyrenes
• poly(3,4-ethylene dioxythiophene)
• polystyrene sulfonic acid
• Gold
• Methanol
• Silicon

Topics

• Bridged Bicyclo Compounds, Heterocyclic (chemistry)
• Cell Adhesion
• Cell Line, Tumor
• Electric Impedance
• Electrodes, Implanted
• Electrophysiology (instrumentation)
• Gold (chemistry)
• Humans
• Laminin (chemistry)
• Materials Testing (methods)
• Methanol (chemistry)
• Microscopy, Atomic Force
• Microscopy, Electron, Scanning
• Nerve Tissue
• Nervous System (chemistry, cytology)
• Neurons (cytology)
• Peptides (chemistry)
• Polymers (chemistry)
• Polystyrenes (chemistry)
• Silicon (chemistry)
• Surface Properties