A glucose biosensor based on modified-enzyme incorporated within electropolymerised poly(3,4-ethylenedioxythiophene) (PEDT) films

Benoît Piro (1) , Dang Lan Anh (1) , Pham Minh Chau (1) , Silvia Fabiano (2, 3) , Tran-Minh Canh (2, 3)

1 ITODYS (UMR_7086) - Interfaces, Traitements, Organisation et Dynamique des Systèmes
2 SPIN-ENSMSE - Centre Sciences des Processus Industriels et Naturels
3 P2MC-ENSMSE - Département Poudres et Matériaux Multi-Composants

We have constructed and characterised a glucose sensor using glucose oxidase (GOD) covalently attached to carboxylic acid polyethyleneglycol (PEG), called (PEG–GOD). This modified enzyme was entrapped afterwards within poly(3,4-ethylenedioxythiophene) (PEDT) films electrogenerated on glassy carbon (GC) electrodes. The composite (PEG–GOD/PEDT) film is more porous than the film without enzyme (PEDT+PEG). Data from electrochemical quartz microbalance (ECQM) and pH-stat experiments indicate a good relative activity of the modified enzyme, ca. 12–15%. Amperometric measurements, using ferrocenemethanol as the redox mediator, confirms that the modified enzyme is catalytically active. The effect of film thickness was also investigated. The sensitivities were quite similar for modified-GOD electrodes (ca. 3 mA cm−2 M−1) and unmodified-GOD electrodes (ca. 2.7 mA cm−2 M−1) but a better stability was obtained with modified PEG–GOD electrodes.

Mots clés: Biosensors; Covalent immobilisation; Conducting polymers; Glucose; Electrochemical quartz microbalance

Domaines: Génie des procédés; Biotechnologies; Biotechnologie

Benoît Piro, Dang Lan Anh, Pham Minh Chau, Silvia Fabiano, Tran-Minh Canh. A glucose biosensor based on modified-enzyme incorporated within electropolymerised poly(3,4-ethylenedioxythiophene) (PEDT) films. Journal of electroanalytical chemistry and interfacial electrochemistry, 2001, 512 (1-2), pp.101-109. ⟨10.1016/S0022-0728(01)00595-2⟩. ⟨emse-00527308⟩