Carbon nanotubes non-covalently functionalized with cytochrome c: A new bioanalytical platform for building bienzymatic biosensors

C. VENEGAS, S. BOLLO; M. EGUÍLAZ, A. GUTIERREZ, G. RIVAS

MICROCHEMICAL JOURNAL

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2016 vol. 128 p. 161 - 165

0026-265X

Wereport for the first timethe use of glassy carbon electrodes (GCE)modified by drop-coating with multi-walled carbon nanotubes (MWCNTs) dispersed in cytochrome c as platformfor the construction of bienzymatic biosensors, using the glycoenzyme glucose oxidase (GOx) as model. The sensitivity of the resulting biosensor at −0.050 V towards glucose using hydroquinone (H2Q) as redox mediator was (96 ± 2) μA M−1, with a linearrange between 1.00 × 10−4 M and 1.00 × 10−3 M and a detection limit of 8 μM. The biosensor demonstratedto be highly reproducible with RSD. values of 6.1% for five different bioelectrodes. The combination of the excellent dispersing properties of Cyt c, the stability ofMWCNTs-Cyt c dispersion and the intimate interaction between Cyt c, MWCNTs and GOx, allowed the construction of an efficient glucose biosensor successfully used to determine glucose in commercial beverages.