An amperometric biosensor for L-glutamate determination prepared from L-glutamate oxidase immobilized in polypyrrole-polyvinylsulphonate film

Figures & data

Figure 1. Growth of PPy-PVS films in aqueous solution of 0.1 M pyrrole and 2.5 mL 25.0% PVS at a scan rate of 50 mV/s versus Ag/AgCl electrode (3.0 M KCl)).

Figure 2. Scanning electron micrograph of PPy-PVS electrode surface.

Figure 3. Reaction scheme for the Glu determination.

Figure 4. The effect of potential on the response of the Pt/PPy-PVS electrode to hydrogen peroxide (in the glycine buffer (pH 9.0).

Figure 5. The effect of glutaraldehyde amounts on the response of the biosensor (at 25°C, 1.0 × 10^{− 7}–1.0 × 10^{− 3} M Glu at 0.3 V operating potential). (

) 0.08% glutaraldehyde, (

) 0.13% glutaraldehyde (

) 0.67% glutaraldehyde.

Figure 6. The effect of pH on the response of the biosensor (at 25°C, 1.0 × 10^{− 3} M Glu, at 0.3 V operating potential).). (

) 0.1 M phosphate buffer, (

) 0.1 M glycine buffer.

Figure 7. The effect of temperature on the response of the biosensor (at pH 9.0, 1.0 × 10^{− 3} M Glu at 0.3 V operating potential).

Figure 8. (A) The effect of Glu concentration on the response of the biosensor (at 0.1 M pH 9.0 glycine buffer, 25°C, 0.3 V operating potential). (B) The calibration curve of Glu biosensor (at 0.1 M, pH 9.0 glycine buffer, 25°C). (C) The calibration curve of Glu biosensor (at 0.1 M, pH 9.0 glycine buffer, 25°C). (D) The calibration curve of Glu biosensor (at 0.1 M, pH 9.0 glycine buffer, 25°C).

Figure 9. Operational stability of the biosensor in pH 9.0 glycine buffer, at a 0.3-V operating potential, 25°C.

Figure 10. Storage stabilization of the biosensor in pH 9.0 glycine buffer, at a 0.3-V operating potential, 25°C.