Rhoeo discolor leaf extract as a novel immobilizing matrix for the fabrication of an electrochemical glucose and hydrogen peroxide biosensor
| Autor: | Seetharamaiah Nalini, Gurukar Shivappa Suresh, Seetharamaiah Nandini, P. Niranjana, Sangaraju Shanmugam, Jose Savio Melo |
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| Rok vydání: | 2014 |
| Předmět: |
Detection limit
biology General Chemical Engineering General Engineering Analytical chemistry Chronoamperometry Horseradish peroxidase Analytical Chemistry chemistry.chemical_compound chemistry biology.protein Glucose oxidase Differential pulse voltammetry Cyclic voltammetry Hydrogen peroxide Biosensor Nuclear chemistry |
| Zdroj: | Anal. Methods. 6:863-877 |
| ISSN: | 1759-9679 1759-9660 |
| Popis: | A novel natural immobilizing matrix for the immobilization of glucose oxidase (GOx) and horseradish peroxidase (HRP) is presented in this article. The electrochemical biosensor was constructed by immobilizing the enzymes on Rhoeo discolor (Rd) leaf extract with 2.5% glutaraldehyde (GLD) on functionalized multiwalled carbon nanotubes (f-MWCNTs) modified graphite (Gr) electrode. The Gr/f-MWCNTs/(Rd-GLD)/GOx and Gr/f-MWCNTs/(Rd-GLD)/HRP biosensors showed excellent electrocatalytic activity concerning the detection of glucose and hydrogen peroxide. The physical morphology of the biosensors was studied using SEM and EDX. The electrochemical performance of the proposed biosensors was evaluated using cyclic voltammetry, differential pulse voltammetry and chronoamperometry. The effects of experimental variables such as pH, temperature, and applied potential on the current response of the biosensors were studied and optimized. The Gr/f-MWCNTs/(Rd-GLD)/GOx biosensor exhibited a rapid response time of less than 5 s, displayed a wide linear range of 0.5 to 28.5 mM, showed a low detection limit of 0.16 μM and revealed a high sensitivity of 15 μA mM−1 cm−2 for glucose. Similarly the Gr/f-MWCNTs/(Rd-GLD)/HRP biosensor showed a fast response time of 3 s, a good linear range of 0.2 to 6.8 mM with a 0.01 μM detection limit and an exceptional sensitivity of 2.1 mA mM−1 cm−2 for hydrogen peroxide. Subsequently, the practical applicability of the glucose biosensor for the analysis of glucose in Eleusine coracana wine and tender coconut water was examined while the Gr/f-MWCNTs/(Rd-GLD)/HRP modified electrode was tested for the determination of H2O2 in herbal bleach. In addition, the biosensors displayed long term stability, anti-interference ability and good reproducibility. |
| Databáze: | OpenAIRE |
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