In the past decade, application of nanotechnology to cell biology has opened promising strategies for tissue regeneration and, more recently, for nerve tissue recovery after brain injury.These applications with potential clinical impact involve the use of biocompatible nanostructured scaffolds.Among them, carbon-based materials, and in particular carbon nanotubes (CNTs), are increasingly investigated in neurobiology field. CNTs’ outstanding electrical conductivity combined with dimensions comparable to fibril extracellular matrix (ECM) constituents and with the ability to drastically reduce glial scar formation pose them as promising tools to specifically interact with CNS’ cells at the nanoscale. In this framework,CNTs ability to boost neuronal activity is particularly intriguing. Here, we investigate the interaction between CNTs forests, directly grown on 2D and 3D scaffolds, through a catalytic chemical vapor deposition (CCVD) technique, and cultured primary neurons, with the final purpose to develop a reliable approach to drive the entire neuronal network development.
The resulting nano-hybrid system (CNTs-based scaffolds interfaced with neurons) was characterized in morphology via fluorescence microscopy and scanning electron microscopy (SEM), and functionally monitoring network electrical activity via intracellular calcium waves (Ca2+ imaging). The results revealed that neurons adhere well to CNTs extending their neurites and creating intimate and tight contacts with them. Remarkably, our CNTs substrates can effectively improve neuronal electrical performance, an effect already observed for drop-casted CNT carpets, but never verified for CVD grown nanotubes. Moreover, we start evaluating neuronal membranes interactions with CNTs environment at the nanoscale using atomic force microscopy (AFM) in order to highlight the possible mechanism responsible for the described effects on neuronal activity.
In addition, the versatility of our synthesis method allows to realize complex 2D patterns of CNTs or 3D CNTs architectures (e.g. decorating porous iron-based materials), modifications difficulty achievable by the simple drop-casting approach. Our results suggest the exciting possibility to “tune” neural network behavior by exploiting 2D and 3D CNTs-based structure providing, in this way, a smart tool for the design of synthetic biomaterials for neuro-medicine applications.
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