Fabrication of surface-modified poly(3-aminobenzoic acid)/multiwalled carbon nanotubes composite thin films for hydrogen peroxide sensing

ABSTRACT

This work reports the fabrication of poly(3-aminobenzoic acid), (PABA)/multiwalled carbon nanotubes (MWNTs) composite thin film modified with layer-by-layer (LbL) self-assembled multilayers of cytochrome C (Cyt C) and poly(diallyldimethylammonium chloride) (PDADMAC) for hydrogen peroxide (H₂O₂) sensing on indium tin oxide-coated glass substrate. An electropolymerized PABA/MWNTs composite thin film was employed for the covalent attachment of Cyt C. The subsequent multilayers of PDADMAC and Cyt C were then fabricated using LbL deposition technique. The fabricated film was characterized by UV-vis spectroscopy, Raman spectroscopy, SEM and AFM. The modified thin film was finally used for successive detection of H₂O₂ at constant applied potential through an electrochemical method.

KEYWORDS:

• Composite
• electrochemical method
• hydrogen peroxide
• multiwalled carbon nanotubes
• poly(3-aminobenzoic acid)
• sensing

Acknowledgements

This work was supported by the CMU Mid-Career Research Fellowship program of Chiang Mai University. The partial support from the Graduate School, Chiang Mai University is also acknowledged. The authors would like to acknowledge Mr. Suruk Udomsom from Biomedical Engineering Center, Chiang Mai University for AFM measurement.