Supramolecular architecture based on the self-assembling of multiwall carbon nanotubes dispersed in polyhistidine and glucose oxidase: Characterization and analytical applications for glucose biosensing.
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-interferent barrier. The sensitivity at 0.700V 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 day storage at 4°C 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 building up a sensitive, selective, robust, reproducible and stable glucose amperometric biosensor for the quantification of glucose in milk samples.
INFIQC, Departamento de Fisicoquímica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Ciudad Universitaria, 5000 Córdoba, Argentina.
Pablo R
PR
Dalmasso
María L
ML
Pedano
Gustavo A
GA
Rivas
D001234:Aspergillus niger / Q000201:enzymology; D015374:Biosensing Techniques / Q000379:methods*; D055664:Electrochemical Techniques / Q000379:methods; D004800:Enzymes, Immobilized / Q000737:chemistry* / Q000378:metabolism; D005465:Fluorocarbon Polymers / Q000737:chemistry; D005947:Glucose / Q000032:analysis* / Q000378:metabolism; D005949:Glucose Oxidase / Q000737:chemistry* / Q000378:metabolism; D006639:Histidine / Q000737:chemistry*; D006801:Humans; D041943:Infant Formula / Q000737:chemistry*; D037742:Nanotubes, Carbon / Q000737:chemistry*; D012680:Sensitivity and Specificity
D004800:Enzymes, Immobilized; D005465:Fluorocarbon Polymers; D037742:Nanotubes, Carbon; C033223:polyhistidine; C040402:perfluorosulfonic acid; D006639:Histidine; D005949:Glucose Oxidase; D005947:Glucose