Nebulized jet-based printing of bio-electrical scaffolds for neural tissue engineering: a feasibility study

Abstract

In this paper, we investigate the application of a direct writing technique to print conductive patterns onto a bio-compatible electrospun-pyrolysed carbon fibre-based substrate. The result is a first study towards the production of bio-electrical scaffolds that could be used to enhance the promotion of efficient connections among neurons for in vitro studies in the widespread field of neural tissue engineering. An electrospinning process is employed for the production of the materials derived from the precursor Polyacrylonitrile (PAN), in which the analysis of the embedment of carbon nanotubes (CNTs) is also investigated. Subsequently, the research methodology of suitable printed electronic parameters, using a commercial silver silver nano-particle (AgNPs, Øavg,particle size ~ 100 nm) ink, is described. The results show values of 2 Ω*cm in the resistivity of the carbon-fibre materials and conductive printed lines of ~50 Ω resistance on glass, and less than ~140 Ω on carbon-fibre samples. Biocompatibility results demonstrate the possibility to use electrospun-pyrolysed mats, also with the embedment of CNTs, as potential neural substrates for a spatially localized electrical stimulation (ES) across a tissue. In addition, the data concerning the potential toxicity of silver suspension are in accordance with the literature, showing a dose-dependent behaviour. This work is pioneer in the feasibility study of using the flexible and versatile printed electronic (PE) approach, combined with engineered bio-compatible substrates, for the realisation of integrated bio-electrical scaffolds for in vitro neural tissue engineering applications.