Behavior of two and three electrodeconfiguration and different mediators inworking electrode on development ofdisposable screen-printing biosensors fordetermination of free cholesterol

In the present work the development of an amperometrictransducer in order to build a free cholesterol biosensor in planarconfiguration is reported. The one single use disposable biosensorswere constructed by screen printing process which is compatible withautomated methodologies of production. Based in the incorporationof tetracyanoquinodimethane (TCNQ), Prussian blue (PB) or ferrite(Fe3O4) as mediator or electrocatalytic agent, three types of electrochemicaltransducers were evaluated. The cholesterol biosensorsrequire a sample volume of 7.2 L, exhibits good reproducibility andselectivity and cover a lineal answer of 2-16 mM with detection limitsfrom 0.3 to 1.6 mM. The characteristics of biosensors are satisfactoryfor the decentralized analysis of the lipid in blood since enclose therange of clinical interest (3.5-6.5 mM)