Biomolecules-carbon nanotubes doped conducting polymer nanocomposites and their sensor application

• Published in: Talanta (Oxford) 2007-12, Vol.74 (3), p.370-375
• Main Authors: Kum, Maxwell C., Joshi, Kanchan A., Chen, Wilfred, Myung, Nosang V., Mulchandani, Ashok
• Format: Article
• Language: English
• Subjects: Absorption; Animals; Biomolecule; Biosensing Techniques - instrumentation; Biosensor; Carbon nanotubes; Cattle; Conducting polymer; Cytochromes c; Electrochemistry; Horseradish Peroxidase - chemistry; Horseradish Peroxidase - metabolism; Nanocomposite; Nanocomposites - chemistry; Nanotubes, Carbon - chemistry; Polymers - chemistry; Polypyrrole; Proteins - chemistry; Pyrroles - chemistry; Serum Albumin, Bovine; Solubility
• ISSN: 0039-9140; 1873-3573
• DOI: 10.1016/j.talanta.2007.08.047

A simple method for preparing bio-functionalized soluble single-walled carbon nanotubes (SWNTs) is described. Different proteins such as bovine serum albumin (BSA), cytochrome c and horseradish peroxidase (HRP) were used to solubilize low functionality SWNTs in water aided by sonication. The unbound proteins were removed by column chromatography and the SWNT-protein conjugate was used as the sole anionic dopant in electropolymerization of polypyrrole from polymerization solution at pH above the isoelectric point of the protein to provide a negative charge. The morphology of the polypyrrole with SWNT-protein dopant was found to be three-dimensional and fibrous with wide open interlocking pores in contrast to smooth and cauliflower-like for chloride doped polypyrrole. Enhanced sensor performance was demonstrated for hydrogen peroxide detection on polypyrrole/SWCNT-HRP nanocomposites modified electrode. Such nanocomposites can be potentially applied for other biosensor and bio-fuel cell applications.