Multifunctional pyrolytic carbon scaffolds for stem cell research

Stem cells have the ability to both self-renew and differentiate into specialized cells in response to appropriate signals. Cell replacement therapy using stem cells is one future strategy for Parkinson’s disease.
Sophisticated micro/nano surfaces/structures have been employed as one way towards better understanding of cell to cell signalling mechanisms. In the presence of such structures, cells are continuously subjected to mechanical forces that influence cell division, gene expression, migration, morphogenesis and adhesion [1]. Pyrolytic carbon has been used as a tissue engineering scaffold in biosensing and life science applications due to its ability to be patterned as well as multifunctional nature i.e. conductivity, biocompatibility and mechanical support [2,3].
This work presents the microfabrication and evaluation of 2D (flat) and 3D pyrolytic carbon surfaces/scaffolds (ordered and unstructured micronanograss, Figure 1 top panel) serving both as a support for in vitro differentiation of human neural stem cells (hNSCs) and as an electrochemical sensor for the subsequent amperometric detection of potassium stimulated dopamine exocytosis. 3D topographies were microfabricated to guide the differentiation of hNSCs (Figure 1b & c top panel). 3D structures are believed to better mimic the in vivo environment by providing mechanical and structural support to enhance stem cells growth and differentiation. Our preliminary investigations show that 3D carbon micro/nanostructures (Figure 1b & c, bottom panel) enhance neurogenesis and maturation of hNSCs into dopaminergic neurons. In Figure 1d it can also be observed that the dopamine peak currents are significantly higher for the 3D structures.