Thesis title: Carbon and Platinum Nanostructured Electrodes on Miniaturized Devices for Biomedical Diagnostics
Fully integrated CNT-based biochip for a real-time monitoring of human metabolites
Irene Taurino, PhD Student, EPFL-IC-LSI
Sandro Carrara, Lecturer and Senior Scientist, EPFL-IC-LSI
Recently, in medical field the necessity of sensors able to monitor metabolic molecules is increasing more and more. In particular, electrochemical biosensors have acquired considerable interest. Many bio-compounds are not electro-active at specific redox potentials. To overcome this drawback, redox enzymes are often incorporated into the sensor. Furthermore, carbon nanotubes (CNTs) have raised great expectations in electrochemical sensing due to their small size, their modifiable surface and their excellent conductivity properties. In addition, their ability to promote the direct electron transfer of enzymes at electrode surface and their electro-catalytic effects for hydrogen peroxide, product of oxidases-based reactions, make them very promising components in biosensors.
The aim of this project is to develop a fully integrated CNT-based electrochemical biosensor for a real-time monitoring of human metabolites. The first point is to evaluate how different multi-walled CNT (MWCNT) treatments (e.g. chemical, electrochemical), densities and orientations (ranging from randomly oriented to well organized nanostructures) can influence bio-sensing performances. In order to increase the specificity and the affinity in biomolecule detection the device could be also based on new enzymes, variant of the commercial ones. The second step is the selection of the best attachment for redox proteins on the outer surface of CNTs (e.g. hydrophobic and electrostatic interactions, covalent bonding, polymer coatings) in order to prevent their denaturation and leaching.