Neuronal Tissue Engineering

The polymer/SWCNT composites can be used as Scaffolds in tissue engineering. The donor-acceptor interactions can be used to assemble thin polymer/SWCNT films stepwise. This method also can be expended to more thermally and oxidatively stable polymer systems. For example, the P4VP/SWCNT films can be used as scaffolds for the synthesis of novel hybrid structures (Correa-Duaite et al., 2004). The polyethyl-enimine (PEI)-SWCNTs composites were used as a substrate for cultured neurons, and promoted neurite outgrowth and branching (Rouse et al., 2004). Correa-Duarte et al. (2004 Landi et al., 2005) reported that 3D-MWCNT-based networks are ideal candidates for scaffolds/matrices in tissue engineering. 

Predefined patterning or network of cells is important for cellular/tissue function and neuronal activities. Cell patterning has a wide range of applications such as tissue engineering, wound healing, biosensors, and cell migration studies. 

Cullen, D.K., Patel, A.R., Doorish, J.F., Smith, D.H., Pfister, B.J., 2008. Developing a tissue-engineered neural-electiical relay using encapsulated neuronal constructs on conducting polymer fibers. J. Neural Eng. 5, 374—384. 

Prabhakaran, M.P., Venugopal, J.R., and Ramakrishna, S. (2009) Mesenchymal stem cell differentiation to neuronal cells on electrospun nanofibrous substrates for nerve tissue engineering. Biomaterials, 30 (28), 49%-5003. 

The term biocompatibility is defined as the ability of a material to perform with an appropriate host response in a specific situation" (Williams 2008). A biocompatible material can be inert, where it would not induce a host immune response and have little or no toxic properties. A biocompatible material can also be bioactive, initiating a controlled physiological response. For porous silicon, bioactive properties were initially suggested based on the observation that hydroxyapatite (HA) crystals grow on microporous silicon films. HA has implications for bone tissue implants and bone tissue engineering (Canham 1995). An extension of this work showed that an applied cathodic current was able to further promote calcification on the surface (Canham et al. 1996). More recently, Moxon et al. showed another example of bioactive porous silicon where the material promoted neuron viability when inserted into rat brains as a potential neuronal biosensor, whereas planar silicon showed significantly fewer viable neurons surrounding the implant site (Moxon et al. 2007). 

Sheam, J., Kinneberg, K., Dyment, N., Galloway, M., Renter, C., Wylie, C., Butler, D., 2011. Tendon tissue engineering progress, challenges, and translation to the clinic. J. Musculoskelet. Neuronal Interact. 11, 163—173. 

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