Abstract: An array of molecular chains is added to a dielectric material between two electrodes of a capacitive affinity sensor. Such an array of molecular chains greatly changes dielectric properties between the two electrodes to greatly enhance sensitivity of the sensor. In a sensor using direct binding, a viral fragment is bound to the sensor's surface. A molecular chain, comprising an anti-viral antibody, an anti-human antibody, and a protein molecule, binds to the viral fragment. In a sensor using competitive binding a hapten is bound to the sensor's surface. A molecular chain, comprising an antibody with attached aliphatic hydrocarbons, binds to the hapten. A free analyte competes with the hapten to bind with the antibody.