Amperometric urea biosensor based on immobilized urease on polypyrrole and macroporous polypyrrole modified Pt electrode

Authors : Maliheh HOSSEINIAN, Ghasem NAJAFPOUR, Ahmad RAHIMPOUR

Pages : 1063-1074

View : 17 | Download : 12

Publication Date : 0000-00-00

Article Type : Research Paper

Abstract :Biosensing of urea by a biosensor as a direct detection method at ambient temperature and pressure instead of chromatography leads to a significant reduction in processing costs. Amperometric biosensors based on urease immobilization on macroporous polypyrrole insert ignore into journalissuearticles values(MPPy); and pyrrole on the surface of a Pt electrode were developed. Applying cyclic voltammetry insert ignore into journalissuearticles values(CV);, we demonstrated the synthesis of MPPy using monodispersed polystyrene spheres insert ignore into journalissuearticles values(460 nm); as a template. CV and chronoamperometric studies were conducted to evaluate the electrochemical current of the modified electrodes. For the electrode with polypyrrole insert ignore into journalissuearticles values(PPy);, the biosensor response was linear in the range of 1.67--8.32 mM insert ignore into journalissuearticles values(R$^{2}$ = 0.99);. Sensitivity, detection limit, and response time of this biosensor were 0.0035 mA mM$^{-1}$, 2.57 mM, and $\sim $7 s, respectively. For the electrode with MPPy, the linear range was 0.5-10.82 mM insert ignore into journalissuearticles values(R$^{2}$ = 0.99);. For this biosensor, sensitivity, detection limit insert ignore into journalissuearticles values(S/N = 3);, and response time were 0.0432 mA mM$^{-1}$, 0.208 mM, and $\sim $5 s, respectively. The modified biosensor with MPPy showed high stability and desirable selectivity for urea.
Keywords : Cyclic voltammetry, electrochemical biosensor, enzyme activity, macroporous polypyrrole