Asymmetric, nano‐textured surfaces influence neuron viability and polarity

Abstract

Three dimensional, nanostructured surfaces have attracted considerable attention in biomedical research since they have proven to represent a powerful platform to influence cell fate. In particular, nanorods and nanopillars possess great potential for the control of cell adhesion and differentiation, gene and biomolecule delivery, optical and electrical stimulation and recording, as well as cell patterning. Here, we investigate the influence of asymmetric poly(dichloro-p-xylene) (PPX) columnar films on the adhesion and maturation of cortical neurons. We show that nanostructured films with dense, inclined polymer columns can support viable primary neuronal culture. The cell-nanostructure interface is characterized showing a minimal cell penetration but strong adhesion on the surface. Moreover, we quantify the influence of the nano-textured surface on the neural development (soma size, neuritogenesis, and polarity) in comparison to a planar PPX sample. We demonstrate that the nanostructures facilitates an enhancement in neurite branching as well as elongation of axons and growth cones. Furthermore, we show for the first time that the asymmetric orientation of polymeric nanocolumns strongly influences the initiation direction of the axon formation. These results evidence that 3D nano-topographies can significantly change neural development and can be used to engineer axon elongation. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 1634-1645, 2018.

Correlating Surface Plasmon Resonance Microscopy of Living and Fixated Cells with Electron Microscopy Allows for Investigation of Potential Preparation Artifacts

“…Mater. Interfaces 2020, 7,1901991 was reached. Afterward, we imaged the cross-section with the integrated SEM system and continued FIB sectioning from the opposite side in order to prepare a thin lamella from the center of the cell.…”

“…The fixation, heavy metal stainings, and resin embeddings were carried out based on the protocol established by Belu et al Unless stated otherwise, all the chemicals were purchased from Sigma‐Aldrich. Chemical Fixation : First, the samples were rinsed three times with 37 °C warm PBS.…”

“…Two frequently used preparation techniques are critical point drying (CPD) and resin embedding . In CPD, the chemical fixation is followed by a dehydration of the cell.…”

“…[1][2][3][4][5] Surface modifications such as nanostructures and coatings can act as chemical, mechanical, and topological cues that influence cellsubstrate adhesion, cell migration and even stem cell fate. [2,6,7] In the development of implants such as retina implants, a strong cell-substrate adhesion is crucial for a good cell-electrode communication while mediating a good integrity. [8][9][10] Understanding said interactions requires sophisticated imaging techniques with a resolution in the nanometer range.…”

“…Two frequently used preparation techniques are critical point drying (CPD) and resin embedding. [7,21,31,32] In CPD, the chemical fixation is followed by a dehydration of the cell. Intracellular water is exchanged with ethanol and subsequently replaced with liquid CO 2 , which is afterward transferred into a supercritical fluid and blown off.…”