Biossensores e Bioeletrônica

Characterization of Urea Biosensor Based on the Immobilization of Bacteria Proteus Mirabilis in Interaction with Iron Oxide Nanoparticles on Gold Electrode

Abstract

Yosra Braham, Houcine Barhoumi, Abderrazak Maaref, Amina Bakhrouf, Christine Grauby Heywang, Tauria Cohen Bouhacina and Nicole Jaffrezic-Renault

In this work we describe a new urea biosensor, based on the immobilization of bacteria, Proteus mirabilis on gold electrode. To improve the stability of the bio-system, additional materials were used such as functionalized Fe3O4 nanoparticles (NPs), cationic (PAH), anionic (PSS) polyelectrolytes, Bovine Serum Albumin (BSA) and glutaraldehyde as a cross-linking agent. The electrochemical performances of the developed bacteria biosensor was evaluated using the electrochemical impedance spectroscopy (EIS) and cyclic voltammetry measurements. The adhesion of the bacteria cell on gold electrode was evaluated using contact angle measurements. The morphology of bacteria and its interaction with Fe3O4 nanoparticles were evaluated with the atomic force microscopy (AFM). As a result, a sensitive, stable and reproducible urea biosensor was developed.