. Author manuscript; available in PMC: 2014 Jul 5.
Published in final edited form as: Biosensors (Basel). 2013;3(3):259–282. doi: 10.3390/bios3030259
© 2013 by the authors
licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution license (http://creativecommons.org/licenses/by/3.0/).