Behavior of Two and Three Electrode Configuration and Different Mediators in Working Electrode on Development of Disposable Screen-Printing Biosensors for Sensible Determination of Free Cholesterol

Abstract. In the present work the development of an amperometric transducer in order to build a free cholesterol biosensor in planar configuration is reported. The one single use disposable biosensors were constructed by screen printing process which is compatible with automated methodologies of production. Based in the incorporation of tetracyanoquinodimethane (TCNQ), Prussian blue (PB) or ferrite (Fe3O4) as mediator or electrocatalytic agent, three types of electrochemical transducers were evaluated. The cholesterol biosensors require a sample volume of 7.2 ?L, exhibits good reproducibility and selectivity and cover a lineal answer of 2-16 mM with detection limits from 0.3 to 1.6 mM. The characteristics of biosensors are satisfactory for the decentralized analysis of the lipid in blood since enclose the range of clinical interest (3.5-6.5 mM).