The marker-free on-chip distinction betweenhybridised (double-stranded) DNA (HDNA) anddenatured (single-stranded) DNA (DDNA) hasrecently been demonstrated using ultrashortelectrical pulses. The electrical THzpulses propagate in integrated waveguidesincorporating resonant THz structures ontowhich the genetic material is deposited.For a possible future realisation of a highthroughput array, it is crucial to optimizethe experimental parameters and theresonant structure. In this paper weperform a first numerical study ofdifferent resonator geometries and examinethe influence of critical experimentalparameters on the transmissioncharacteristics of the resonant structures.Our simulations demonstrate that the ringresonator shows a comparable performance tothe parallel-coupled resonator previouslyused in a first demonstration by Nagel andcoworkers.