Chemically modified multiwall carbon nanotube composite electrodes: An assessment of fabrication strategies

Chemically modified electrodes have been widely used to enhance electrochemical monitoring of analytes that are not easily detected using traditional base conductive materials. We have investigated different fabrication approaches to chemically modify multi-wall carbon nanotube (MWCNT) composite electrodes with Prussian blue (PB). Composite electrodes were made where Prussian blue was mixed with MWNCTs, where Prussian blue was coated on MWCNT composite electrodes and where MWCNTs were modified by generating PB on the surface of MWCNTs. Our findings indicate that MWCNT modified PB electrodes provided good sensitivity for the detection of glutathione and exceptional stability; whilst MWCNT coated PB electrodes provided excellent sensitivity but poor stability. Such findings provide important implications on the fabrication, suitability and use of chemically modified electrodes for electroanalysis.