Biomimetic Nanostructures Fabricated by Nanoimprint Lithography for Improved Cell‐Coupling

Abstract

Since the advent of biosensing, structuring of electrode surfaces for the improvement of cell-coupling and electrophysiological properties has been extensively investigated. Most of these methods result in structures with predefined dimensions and regular organization. Nevertheless, natural adhesion surfaces of the cells are hardly uniform. Therefore, this study focusses on fabricating randomly organized nanostructures mimicking the irregular distribution of natural collagen fibers coated on a planar surface. Fiber geometries are replicated by using a spincoating process followed by thermal nanoimprint lithography and gold electroplating. Microscopic studies reveal the width of these biomimetic collagen-like gold nanostructures ranging between 200 nm and 5 µm, with a uniform height of ≈35 nm. In comparison to unstructured gold surfaces, nanostructured surfaces display a decrease in impedance magnitude by 50% for frequencies below 1 kHz and show an increase in critical free surface energy by 35%, the latter translating to an increased surface wettability. Culturing enteric neurons from postnatal mice, a relative hard to handle type of neurons, results in an improved spreading of the neural networks on the nanostructured surfaces.

The Bumpy Road to Stem Cell Therapies: Rational Design of Surface Topographies to Dictate Stem Cell Mechanotransduction and Fate

“…Nanoimprint lithography has been applied to obtain resolution as high as 10 nm. 65 Having to fabricate a master from alternative patterning technologies such as PL is a drawback; however, only one master is required to begin stamping. Defects may develop in the master due to repetitive use, though this will be governed by the inputs to the process.…”

“…An imprintable resist and a template, such as a stamp or mold, with the micro- or nanoscale features to be patterned are required for the process (Figure A). Nanoimprint lithography has been applied to obtain resolution as high as 10 nm . Having to fabricate a master from alternative patterning technologies such as PL is a drawback; however, only one master is required to begin stamping.…”

Nanoimprinting of Biomimetic Nanostructures

“…Randomly organized nanostructures mimicking the irregular distribution of natural collagen fibers were replicated by hot embossing and transferred into gold structures in [199] to improve growth of neurons. PCL membranes were used as substrates for cell growth by Monteiro et al [200].…”

Recent Advances in Patterning Natural Polymers: From Nanofabrication Techniques to Applications

“…In addition, the fabrication of biomimetic nanostructures using natural collagen as a basic material by NIL has also been reported. [ 81 ] These investigations expand the possibility of nanoimprint lithography, holding great potential in broad functional applications.…”