Fabrication of vertically aligned PEDOT nanotube arrays on microelectrodes to interface neurons.

1 Vertically aligned PEDOT nanotube array was directly modified on microelectrodes. 2 PEDOT nanotube array improved electrical properties of microelectrodes. 3 PEDOT nanotube array promoted cell attachment and growth. 4 PEDOT nanotube array stimulated neurite extension with more and longer neurites. To obtain long-term success in chronic implantations, a stable neuron-electrode interface which can seamlessly integrate with brain tissues is required. Compared to conventional flat electrodes, neural electrodes modified with nanostructured materials can provide significantly larger active surface area for charge transfer and neuron-electrode integration. In this study, vertically aligned poly(3,4-ethylenedioxythiophene) (PEDOT) nanotube arrays have been directly fabricated on microelectrodes via a template-mediated technique. It is expected that the PEDOT nanotube arrays could improve the electrical properties of microelectrodes, promote cell adhesion and growth, and increase neurite extension and branching. From our study, ∼2 orders of interfacial impedance decrease and charge capacity density enhancement have been obtained from the PEDOT nanotube array modified microelectrodes. In vitro cellular compatibility tests using PC12 cells showed that PEDOT nanotube arrays supported cell adhesion and growth even without cell adhesion promoted molecules, e.g. collagen and poly-L-lysine (PLL). When treated with nerve growth factor (NGF), larger number of and longer neurites were observed from the cells cultured on PEDOT nanotube arrays compared to those on PLL coated flat substrates. Vertically aligned PEDOT nanotube arrays were directly fabricated on microelectrodes to interface neurons. The PEDOT nanotube arrays significantly improved the electrochemical properties, promoted the attachment and growth, and stimulated the differentiation of PC12 cells with significantly larger number and longer neurites [Display omitted]. [ABSTRACT FROM AUTHOR]