Novel enzyme biosensor for hydrogen peroxide via supramolecular associations.
A polythiolated-beta-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 H(2)O(2) concentrations between 28 microM and 5.5 mM, and a low detection limit of 7 microM. The biosensor showed a sensitivity of 109 microA/Mcm(2) and retained 98% of its initial electrocatalytic activity after 40 days of storage at 4 degrees C in 50mM sodium phosphate buffer pH 7.0. The host-guest supramolecular nature of the immobilization method was confirmed by cyclic voltammetry.
Camacho
Conrado
C
Center for Enzyme Technology, University of Matanzas, Autopista a Varadero km 3 (1/2), Matanzas 44740, Cuba.
Chico
Belkis
B
Cao
Roberto
R
Matías
Juan C
JC
Hernández
Javier
J
Palchetti
Ilaria
I
Simpson
Benjamin K
BK
Mascini
Marco
M
Villalonga
Reynaldo
R
D015374:Biosensing Techniques / Q000295:instrumentation*; D004563:Electrochemistry / Q000295:instrumentation*; D004566:Electrodes; D004800:Enzymes, Immobilized / Q000737:chemistry; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006735:Horseradish Peroxidase / Q000737:chemistry*; D006861:Hydrogen Peroxide / Q000032:analysis* / Q000737:chemistry; D046911:Macromolecular Substances / Q000032:analysis / Q000737:chemistry; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
D004800:Enzymes, Immobilized; D046911:Macromolecular Substances; D006861:Hydrogen Peroxide; D006735:Horseradish Peroxidase