Novel enzyme biosensor for hydrogen peroxide via supramolecular associations

• Published in: Biosensors & bioelectronics Vol. 24; no. 7; pp. 2028 - 2033
• Main Authors: Camacho, Conrado, Chico, Belkis, Cao, Roberto, Matías, Juan C., Hernández, Javier, Palchetti, Ilaria, Simpson, Benjamin K., Mascini, Marco, Villalonga, Reynaldo
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier B.V 15-03-2009; Elsevier
• Subjects: Biological and medical sciences; Biosensing Techniques - instrumentation; Biosensor; Biosensors; Biotechnology; Electrochemistry - instrumentation; Electrodes; Enzyme immobilization; Enzymes, Immobilized - chemistry; Equipment Design; Equipment Failure Analysis; Fundamental and applied biological sciences. Psychology; General aspects; Horseradish peroxidase; Horseradish Peroxidase - chemistry; Hydrogen Peroxide - analysis; Hydrogen Peroxide - chemistry; Immobilization techniques; Macromolecular Substances - analysis; Macromolecular Substances - chemistry; Methods. Procedures. Technologies; Reproducibility of Results; Sensitivity and Specificity; Supramolecular complex; Various methods and equipments; β-Cyclodextrin; Horseradish peroxidase; β-Cyclodextrin; Enzyme immobilization; Biosensor; Supramolecular complex; Hydrogen peroxide; Peroxidases; Enzyme; Immobilization; Peroxidase; Oxidoreductases; Complexes
• ISSN: 0956-5663; 1873-4235
• DOI: 10.1016/j.bios.2008.10.008

A polythiolated-β-cyclodextrin polymer was synthesized and used as a coating material for gold electrodes. The functionalized electrodes were employed for immobilizing adamantane-modified horseradish peroxidase via supramolecular associations. The enzyme-containing electrode was used as an amperometric biosensor device with 1mM hydroquinone as electrochemical mediator. The biosensor exhibited a fast amperometric response (10s), a good linear response toward H2O2 concentrations between 28μM and 5.5mM, and a low detection limit of 7μM. The biosensor showed a sensitivity of 109μA/Mcm2 and retained 98% of its initial electrocatalytic activity after 40 days of storage at 4°C in 50mM sodium phosphate buffer pH 7.0. The host–guest supramolecular nature of the immobilization method was confirmed by cyclic voltammetry.