Synthesis and characterization of carbon nanotubes on clay minerals and its application to a hydrogen peroxide biosensor

• Published in: Materials Science & Engineering C 2009, Vol.29 (1), p.55-61
• Main Authors: Hsu, Hao-Lin, Jehng, Jih-Mirn
• Format: Article
• Language: English
• Subjects: Biosensor; Carbon nanotubes; Clay mineral; Glucose; Glucose oxidase
• ISSN: 0928-4931; 1873-0191
• DOI: 10.1016/j.msec.2008.05.011

In this study, we demonstrate the synthesis of carbon nanotubes (CNTs) on clay minerals, and the development of biosensors based on Nafion–CNT/Clay–Au and Nafion–CNT/Clay–Au–Glucose oxidase (GOD) composite films for the detection of hydrogen peroxide (H 2O 2) and glucose, respectively. The CNTs are synthesized on nickel cation exchanged clay mineral platelets. From field-emission scanning electron microscope images, X-ray diffraction, Fourier transfer infrared and thermogravimetric analysis results, the clay layers are exfoliated and delaminated after the growth of CNTs on them. The mixed hybrid film of Nafion, CNT/Clay, Au particles and GOD is coated on the glassy carbon (GC) electrode to detect H 2O 2 or glucose. This film exhibits a detection limit of 5.0 × 10 − 5 M for H 2O 2 with a sensitivity of 280 nA mM − 1 . In addition, the amperometric response for glucose containing 2.0 mg mL − 1 GOD in the Nafion–CNT/Clay–Au–GOD modified GC electrode exhibits a sensitivity of 620 nA mM − 1 with a linear range up to 1850 μM. A higher sensitivity and shorter response time are observed with increasing GOD content in the composite matrix film. Besides, the highest sensitivity of 2032 nA mM − 1 is obtained with the addition of the 10.0 mg mL − 1 GOD in the composite film. Consequently, the CNT/Clay/Nafion medium can probably be a useful electrode for the development of sensors due to its high sensitivity and applicability.