CuS thin films coated with bioglass 45S5/TiO2 Nps and Zeolite ZMS5 thin films as a principle of an urea biosensor

Abstract

In recent years, the development of biosensors created from materials obtained through reproducible and low-cost methods has been of great interest. In the present work, we report the immobilization of urease in CuS thin films coated with bioglass and zeolite by adsorption method and the chemical and electrical characterizatiom of the thin films based in different concentrations of urea. These films were characterized by UV Vis spectroscopy and four probe method where an increasing of the ammonium curve and the resistivity of the thin films was observed in order of urea concentration. The synthesis of bioglass 45S5, zeolite ZMS5 and 1.5[Ti], titanium dioxide (TiO2) nanoparticles (including the bioglass composite) were achieved by sol gel method and characterized by FTIR, and copper sulfide thin films were obtained by chemical bath deposition. For the deposition of biomaterial thin films, spin coating method was chosen, in order to deposit each biomaterial, the bioglass was scattered in methanol and the zeolite in acetone, and then the deposition of these materials was made over the CuS thin films. By characterizing these thin films with UV Vis, SEM it was obtained a homogeneity in the deposition and a porous structure adequate to immobilize the enzyme, were the view of the two phases of the depositio, the biomaterial and the semiconductor, was clear.