INFIQC   05475
INSTITUTO DE INVESTIGACIONES EN FISICO- QUIMICA DE CORDOBA
Unidad Ejecutora - UE
artículos
Título:
Supramolecular architecture based on the self-assembling of multiwall carbon nanotubes dispersed in polyhistidine and glucose oxidase: characterization and analytical applications for glucose biosensing
Autor/es:
P. D. DALMASSO; M.L. PEDANO; G. A. RIVAS
Revista:
BIOSENSORS & BIOELECTRONICS
Editorial:
ELSEVIER ADVANCED TECHNOLOGY
Referencias:
Lugar: Amsterdam; Año: 2013 vol. 39 p. 76 - 81
ISSN:
0956-5663
Resumen:
We report for the first time the development of a sensitive and selective glucose biosensor based on the self-assembling of multiwall carbon nanotubes (MWCNTs) dispersed in polyhistidine (Polyhis) and glucose oxidase (GOx) on glassy carbon electrodes (GCE). The supramolecular architecture was characterized by SEM, FT-IR and electrochemical techniques. The optimum multistructure was obtained with five (MWCNT-Polyhis/GOx) bilayers and one layer of Nafion as anti-interferents barrier. The sensitivity at 0.700 V was (1.94 ± 0.03) mAM-1 (r:=0.9991), with a linear range between 0.25 and 5.00mM, a detection limit of 2.2µM and a quantification limit of 6.7µM with minimum interference from lactose (1.5%), maltose (5.7%), galactose (1.2%), ascorbic acid (1.0 %), and uric acid (3.3%). The biocatalytic layer demonstrated to be highly reproducible since the R.S.D. for 10 successive amperometric calibrations using the same surface was 3.6%. The sensitivity of the biosensor after 15 days storage at 4oC remained at 90 % of its original value. The combination of the excellent dispersing properties and polycationic nature of polyhistidine, the stability of the MWCNT-Polyhis dispersion, the electrocatalytic properties of MWCNTs, the biocatalytic specificity of GOx, and the permselective properties of Nafion have allowed to build up a sensitive, selective, robust, reproducible and stable glucose amperometric biosensor for the quantification of glucose in milk samples.