Urea Amperometric Biosensors Based on Nanostructured Polypyrrole

Abstract

In this work, we report the development of urea biosensors using macroporous polypyrrole as electrochemical transducer. Nanostructured polypyrrole was synthesized using monodispersed polystyrene spheres (460 nm) as template. Nanostructured urea biosensors were assembled after immobilization of urease (an enzyme that hydrolyses urea to ammonia) on macroporous polypyrrole, which was carried out using two different procedures: covalent attachment or layer-by-layer (lbl) deposition. Results show that lbl assembly of urease on macroporous polypyrrole gives rise to biosensors with improved detection kinetics (as demonstrated by higher I max values) and tunable sensitivities. Comparison with bulk urea biosensors previously described in the literature demonstrates that the use of nanostructured polypyrrole as sensing platform enhances biosensor's analytical performances, mainly due to the availability of more active sites for enzyme immobilization.

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Urea Amperometric Biosensors Based on Nanostructured Polypyrrole and Poly Ortho-Phenylenediamine

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