Immobilization of Uricase Upon Polypyrrole-Ferrocenium Film

Figures & data

Figure 1 SEM of Pt/polypyrrole-ferrocenium film.

Figure 2 SEM of Pt/polypyrrole-ferrocenium-uricase.

Figure 3 SEM of Pt/polypyrrole-ferrocenium-uricase-gelatine.

Figure 4 SEM of Pt/polypyrrole-ferrocenium-uricase-gelatine-glutaraldehyde.

Figure 5 The effect of pH on free and immobilized enzyme.

Figure 6 The effect of temperature on free and immobilized enzyme.

Figure 7 The effect of uric acid concentration upon the amperometric response of free and immobilized uricase (Lineweaver-Burk Plot).

Figure 8 Reuse number of the immobilized enzyme.

Table 1. The properties and the optimum working conditions of immobilized enzyme and free enzyme

	Optimum conditions and characteristic
Parameters	İmmobilized enzyme	Free enzyme
Temperature	55°C	35°C
pH	8.0	8.5
Storage stabilization	The immobilized enzyme maintains 49% of the initial amperometric response at the end of the 7th week.	The free enzyme maintains 42% of the initial amperometric response at the end of the 7th week.
Reproducibility	The electrode maintains 77.7% of the initial amperometric response at the end of the 30th measurement.	–
Km and Vmax	0.44 mM 7.1 × 10^−2 mM/minute	0.39 mM 8.4 × 10^−2 mM/minute