Electroanalytical properties of a novel biosensor modified with zirconium alcoxide porous gels for the detection of acetaminophen.

The development of composite electrodes for biosensors construction based on HRP and zirconium alcoxide film for acetaminophen detection and finally, acetaminophen determination in pharmaceutical products is described. The enzyme immobilization is performed by retention in a polyetilenimine and zirconium alcoxide porous gel film, technique that offers a good entrapping and in the mean times a "protective" environment for the biocomponent. The operation principle of the biosensor is based on monitoring the amperometric signal generated by reduction at the electrode surface of the enzymatically generated quinoneimine from acetaminophen. The resulting biosensor shows a linear response towards acetaminophen with a linear range of 1.96 x 10(-5)M and 2.55 x 10(-4)M and a limit of detection of 1.17 x 10(-7)M. The proposed biosensor shows long term stability and good reproducibility.