Flexible Gold Nanocone Array Surfaces as a Tool for Regulating Neuronal Behavior

Abstract

Accelerated neurite outgrowth of rat cortical neurons on a flexible and inexpensive substrate functionalized with gold nanocone arrays is reported. The gold nanocone arrays are fabricated on Teflon films by a bottom-up approach based on colloidal lithography followed by deposition of a thin gold layer. The geometry of nanocone arrays including height and pitch is controlled by the overall etching time and template polystyrene beads size. Fluorescence microscopy studies reveal high viability and significant morphological changes of the neurons on the structured surfaces. The elongation degree of neurite is maximized on the nanocone arrays created with 1 µm polystyrene beads by a factor of two with respect to the control. Furthermore, the interface between the neurons and the nanocones is investigated by scanning electron microscopy and focused ion beam cross-sectioning. The detailed observation of the neuron/nanocone interfaces reveals the morphological similarity between the nanocone tips and the neuronal processes, the existence of interspace at the interface between the cell body and the nanocones, and neurite bridging among the neighboring structures, which may induce the acceleration of neurite outgrowth. The flexible gold nanocone arrays can be a good supporting substrate of neuron culture with noble electrical and optical properties.

High‐Aspect‐Ratio Nanostructured Surfaces as Biological Metamaterials

“…Nanosphere lithography (also referred to as colloidal lithography) uses the self‐assembly of polymer or microgel‐based nanospheres on a surface . A wide range of variants exist, for a more in depth discussion see the review of Wang et al Controlling the type and size of particle deposited, the surface chemistry, and deposition conditions allows either well‐defined high‐density packing or lower‐density stochastic patterns …”

“…Nanosphere lithography (also referred to as colloidal lithography) uses the self-assembly of polymer or microgel-based nanospheres on a surface. [167,[179][180][181] A wide range of variants exist, for a more in depth discussion see the review of Wang et al [155] Controlling the type and size of particle deposited, the surface chemistry, and deposition conditions allows either well-defined high-density packing [27] or lower-density stochastic patterns. [122] Plasma etching and gel-swelling techniques can also be used to vary the pitch and diameter of the pattern, [153,182] which can then be transferred to the surface via multiple methods, such as ion bombardment [183] or metal-assisted chemical etching.…”

Asymmetric, nano‐textured surfaces influence neuron viability and polarity

“…Brüggemann et al showed staining of neuronal actin filaments with almost no growth cones for gold nanopillar arrays, while a broad growth cone was formed on planar substrates . A direct aspect of the growth cone appearance was reported by Toma et al Accelerated neurite outgrowth of neurons was induced by functionalized gold nanocone arrays …”

“…58 A direct aspect of the growth cone appearance was reported by Toma et al Accelerated neurite outgrowth of neurons was induced by functionalized gold nanocone arrays. 59 To subsume all results presented so far, we can note that the PPX material shows a harmful chemical effect on the cell viability and neurite formation, which becomes apparent if control and PPX samples are compared. The adhesion impairing properties of the PPX is presumably related to their hydrophobic nature according to the high contact angle of the material.…”

Diphenylalanine Peptide Nanowires as a Substrate for Neural Cultures

“…However, having the cells in a matrix complicates post processing and analysis. By culturing in 2.5D on substrates with an alternative topology like for example membranes [7][8][9][10], nanostructures [11,12], or even pillars [13][14][15][16], some of the benefits of 3D culturing can be obtained while providing the possibility of conventional post-culture This work was performed in the laboratories of Winnie E. Svendsen and of Helle S. Waagepetersen handling. Both ordered and random structures have been demonstrated to affect cell growth.…”