Monitoring blood cholesterol with MWNTs

(Nanowerk News) Researchers at the Mechanical and Materials Engineering Department at Florida International University in Miami developed a novel type of working electrode consisting of vertically aligned multiwall carbon nanotubes on a silicon platform. The suggested silicon based CNT working electrode can potentially be integrated with signal processing circuitry and can be part of lab-on-a-chip systems.
The work by Won-Bong Choi and colleagues will be reported in the Feb. 28. 2006 print issue of Nanotechnology. The online version titled "Vertically aligned carbon nanotube probes for monitoring blood cholesterol" was published on Jan. 26, 2006.
Scanning electron microscope image of the vertically aligned thin multiwall carbon nanotubes in the Si platform. (Source and copyright: IoP Publishing)
Surface modification of the MWNT with a biocompatible polymer, polyvinyl alcohol (PVA), converted the hydrophobic nanotube surface into a highly hydrophilic one, which facilitates efficient attachment of biomolecules. The fabricated working electrodes showed a linear relationship between cholesterol concentration and the output signal. The efficacy of themultiwall carbon nanotubes in promoting heterogeneous electron transfer was evident by distinct electrochemical peaks and higher signal-to-noise ratio as compared to the Au electrode with identical enzyme immobilization protocol.
Source: Florida International University