Posted on Jan 30, 2014, 6 a.m.
Carbon nanofibers added to a chitosan-based composite material not only support the scaffold, but allow celectrical impulses to pass.
When damaged, adult heart tissue is unable to heal itself thoroughly, so researchers are now exploring ways to regenerate the lost tissue – but do so with nontoxic materials that avoid attack by the body's immune system, and permit the cells to pass the electrical signals necessary for the heart to beat. Chitosan, which is obtained from shrimp and other crustacean shells, has been successfully used as a scaffold for growing heart cells; however, it does not transmit electrical signals well. Gordana Vunjak-Novakovic, from Columbia University (New York, USA), and colleagues added carbon nanofibers, which can conduct electricity, to the chitosan, and grew neonatal rat heart cells on the resulting scaffold. After two weeks, cells had filled all the pores and showed far better metabolic and electrical activity than with a chitosan scaffold alone. The cells on the chitosan/carbon scaffold also expressed cardiac genes at higher levels. The study authors submit that: “This study demonstrates that the incorporation of carbon nanofibers into porous chitosan scaffolds improved the properties of cardiac tissue constructs, presumably through enhanced transmission of electrical signals between the cells.”
Martins AM, Eng G, Caridade SG, Mano JF, Reis RL, Vunjak-Novakovic G. “Electrically conductive chitosan/carbon scaffolds for cardiac tissue engineering.” Biomacromolecules. 2014 Jan 13.