Carbon nanofibers fabrication, surface modifications, and application as the innovative substrate for electrical stimulation of neural cell differentiation

Abstract

AbstractEngineered nanostructures are innovative and precisely designed, synthesized, and tailored with outstanding physicochemical properties that can be applied as the game-changer in neural tissue engineering. The present study aimed to develop an innovative approach based on electrical stimulation through a conductive scaffold to differentiate neural cells from human adipose mesenchymal stem cells without the use of a specific environment for neural differentiation. Electrospun carbon nanofibers (CNFs) were obtained using heat treatment of polyacrylonitrile nanofibers and treated by nitric acid, ethylenediamine, and oxygen Plasma. SEM imaging revealed that the treated nanofibers have s diameter in the range of 120-200 nm and the treatment did not significantly change the CNFs diameter. The FTIR results showed that the treatments were able to introduce COOH, OH, and NH2 functional groups on the CNFS surface. The XRD and Raman analysis showed that the plasma treatment induced the lowest structural changes in the CNFs microstructure. The biocompatibility assessments showed that the pristine and treated CNFs were non-toxic induced proliferative effect on human adipose-derived mesenchymal stem cells. The electrical stimulation (1.5 mA current with a frequency of 500 Hz and CMOS waveform for 7 days 10 min each day) induced the expression of neural genes and proteins by the cells cultured on the treated CNFs. The Plasma-treated CNFs mediated the highest differentiation outcome. These results indicate that electrospun CNFs can be applied as the innovative interface applicable for neural tissue regeneration under electrical stimulation.Research highlightsCNFs were fabricated from PAN nanofibersDifferent amounts of ZnONPs were incorporated into or sprayed on CNFincreasing in ZnONP amount decreased conductivity, surface wettability was improved by ∼19–33%.Also, FTIR, XRD, and Raman analyses proved that the presence of ZnONP improved structure formation with lower defect densitySchematic 1.The applied electrical stimulation setup