Funtionalization of bamboo-like carbon nanotubes with 3-mercaptophenylboronic aid-modified gold nanoparticles for the development of a hybrid gluccose enzyme electrochemical biosensor

MARCOS EGUILAZ,; VILLALONGA REYNALDO; PINGARRÓN JOSÉ MANUEL; FERREYRA N. F.,; G. A. RIVAS

SENSORS AND ACTUATORS B-CHEMICAL

ELSEVIER SCIENCE SA

Lugar: Amsterdam; Año: 2015 vol. 216 p. 629 - 637

0925-4005

tWe report for the first time a sensitive and selective glucose biosensor based on the immobilization atglassy carbon electrodes (GCE) of a new hybrid nanomaterial consisting of gold nanoparticles functional-ized with 3-mercaptophenyl boronic acid (AuNPs-B(OH)2) and bamboo-like multiwall carbon nanotubes(bMWCNT) dispersed in hyperbranched polyethyleneimine (PEI). The presence of boronic acid residuesallowed the supramolecular immobilization of glucose oxidase (GOx) as a model glycoenzyme whilethe hybrid nanomaterial Au(NP)-bMWCNT produces a synergistic effect on the catalytic detection of theenzymatically generated hydrogen peroxide. The resulting functionalized nanomaterials were character-ized by TEM, FT-IR and electrochemical techniques. The sensitivity at 0.700 V was (3.26 ± 0.03) mA M−1(28.6 mA M−1cm−2), with a linear range between 2.50 × 10−4M and 5.00 × 10−3M, a detection limit of0.8 M and a quantification limit of 2.4 M. The biocatalytic layer demonstrated to be highly reproduciblewith R.S.D. values of 8.6% for 10 successive amperometric calibrations using the same surface, and 4.5%for ten different bioelectrodes. The sensitivity of the biosensor after 14 days of storage at 4◦C remainedat 86.1% of its original value. The combination of the excellent dispersing properties of PEI, the stabil-ity of the bMWCNT-PEI dispersion, the synergistic effect of AuNPs-B(OH)2and bMWCNT towards theelectrooxidation of hydrogen peroxide, and the robust immobilization of GOx at AuNP-B(OH)2allowedbuilding a sensitive, reproducible and stable amperometric biosensor for the quantification of glucose inbeverages and milk samples.