Vertically Aligned Carbon Nanofibers: Interconnecting Solid State Electronics with Biosystems

Abstract

Vertically aligned carbon nanofibers (VACNFs) are grown directly on prefabricated electronic circuits with nanoscale precision. Utilizing the free-standing nanofiber array geometry, we have demonstrated the detection of nucleic acids to construct an ultrasensitive electrochemical sensor. Extending this technology towards in vivo applications, we have modified the free-standing VACNF arrays in order to achieve a multifunctional three dimensional (3-D) matrix that interpenetrates the neuronal network of PC12 cells. We found that PC12 cells cultured on the nanofiber arrays can form an extended neural network upon proper chemical and biochemical modification. The soft 3-D nanofiber array architecture provides a novel platform to fine-tune the topographical, mechanical, chemical, and electrical cues at sub-cellular scales. This biomaterial platform can be used for both fundamental studies of nanomaterial-cell interactions and the development of multifunctional, chronically stable implantable devices. The application of these devices and potential utility as a multifunctional platform for neurophysiology and biochemical studies will be discussed.

Label-free detection of C-reactive protein using a carbon nanofiber based biosensor

“…Following the pre-conditioning of VACNF NEA device as outlined earlier, CV and EIS measurements for bare and modified electrodes were carried out. Figure 1 (a) shows the typical steady state sigmoidal behavior of an individual electrode whereas Figure S3 (a) under Supplementary Information provides CV curves for three different electrodes (E1-E3)) showing the steady state peaks at a potential difference of ~400 mV (Cassell et al, 2009; Koehne et al, 2009; Arumugam et al, 2009, 2010; Siddiqui et al, 2010). The steady state behavior is expected from a spatially patterned isolated nanofiber electrode because of the absence of overlapping diffusion layers and predominant radial diffusion of solution ions (Fe[(CN) 6 ] 3-/4- ) towards the nanoelectrodes.…”

“…have improved tremendously in recent years. Among carbon nanostructures, vertically aligned carbon nanofibers (VACNFs), where each fiber is an individual freestanding nanostructure and acts as a nanoelectrode, have been used successfully to construct biosensors (Li et al, 2005; Cassell et al, 2009; Koehne et al, 2009; Arumugam et al, 2009, 2010; Siddiqui et al, 2010; Periyakaruppam et al, 2011) including detection of cardiac troponin (Periyakaruppam et al, 2013). Due to their small diameter, robustness, high conductivity, biocompatibility and ease of surface modification, VACNF based nanoelectrode arrays (NEAs) serve as a biosensor platform.…”

Engineering Tissues of the Central Nervous System: Interfacing Conductive Biomaterials with Neural Stem/Progenitor Cells

“…[ 259 ] Microarrays of vertically aligned CNFs grown with nanoscale precision directly onto prefabricated electronic circuits or silicon wafers have been fabricated with tunable topographical, electrical, biochemical and mechanical properties. [ 260–262 ] CNFs exhibit a Young's modulus comparable to silicon and significantly lower than CNTs, a property that may impart better biocompatibility when implanted into the brain. [ 263 ] Zhu et al described an alternative approach to generating fibrous, carbon‐based scaffolds in which they thermally annealed electrospun mats of polyacrylonitrile.…”

“…[250,251] They have shown promise as platforms for electrophysiology when fashioned into electrode films and arrays. [252][253][254] While a dose-dependent toxicity of CNTs is recognized, [242,243] researchers have reported good biocompatibility at low doses both in vitro [250] and in vivo. [243] CNTs are amenable to chemical modification, typically after surface oxidation.…”

Vertically Aligned Carbon Nanotubes for Microelectrode Arrays Applications

“…Taking into account their attractive mechanical, thermal, electrical and physical properties in general, CNTs can compete and even overmatch the best metals or semiconductors in the market. Because of this, CNTs have gathered large variety of applications 3 and has made them ideal for their use in electronics and, in particular, as biocatalytical electrodes, 4 interconnexion of biosystems to solid state electronic devices 5 and micro-electrode arrays (MEAS). 6 7 Micro-electrode arrays (MEAs) (Fig.…”