DIAGNOSTIC TEST FOR THE MEASUREMENT OF ANALYTE IN A BIOLOGICAL FLUID

A biosensor for determining the concentration of an analyte, such as, for example, ALT, in a sample of biological fluid, such as, for example, whole blood, comprising: (a) a base layer; (b) a detecting layer comprising a reference electrode and a working electrode, the surface of the electrically conductive portion of the working electrode being sufficiently smooth so tha t determination of the concentration of an analyte present in a low concentration, e.g. less than 1 mM, can be made; (c) a layer overlying said electrodes, said layer comprising dried reagents; and (d) an anticoagulant disposed in such a location that it will prevent the sample from coagulating during the determination. The biosensor preferably further includes a fluid- transporting layer to aid in delivering the sample from a sample application zone to the electrodes. The biosensor preferably further includes a covering layer overlying the electrode area to reduce evaporation of the sample durin g the assay and to help define the fluid transport path and the volume of flui d over the detecting layer.