Aug 15, 2008
Rows of gallium phosphide nanowires guide axons with unprecedented fidelity
Guiding axons is of great importance for building neuronal model systems and for developing new types of prostheses. In vitro, neural networks of controlled architecture can be used to gain insights on cell-to-cell communication. In vivo, regenerating axons can be guided to electrodes for direct detection or stimulation in next-generation prostheses.
Surfaces for axonal guidance are typically achieved in one of two ways. Chemical patterns of molecules that promote cell growth lead to good axonal guidance but are easily destroyed by non-specific protein adsorption. Topographical modification, on the other hand, is a more robust method but leads to a lower degree of axonal guidance.
In a recent article published in Nanotechnology, C Prinz et al. use rows of free-standing nanowires to guide peripheral nerve-cell axons with high fidelity. The nanowires are grown using MOVPE from EBL-defined gold nanoparticles on a gallium phosphide substrate. The distance between nanowires within a row is 400 nm and the distance between two rows is 10 µm. The axons follow the rows of nanowires with high precision and are unable to cross a row of nanowires, in sharp contrast to the situation when grooves are used to guide axons.
A strong interaction between the axons and the nanowires is evidenced by the internalization of the nanowires by the cells and by the localization of the focal adhesion points of the cells to the position of the individual nanowires.
About the author
All of the authors are affiliated to Lund University. Christelle Prinz is a researcher at the Solid State Physics department. Waldemar Hällström is a PhD student at the Solid State Physics department. Thomas Mårtensson holds a shared affiliation as research engineer at QuNano AB and PhD student at the Solid State Physics department. Lars Samuelson is head of the Nanometer Structure Consortium at Lund University and founder of QuNano AB. Lars Montelius is a professor in Solid State Physics, he holds 15 patents and has started several companies in nano-related businesses. Martin Kanje is a professor at the Cell and Organism department.