Label-free probing of the binding state of DNA by time-domain THz sensing

摘要

We present a new approach for the label-free characterization of genetic material. Time-resolved THz transmission analysis of polynucleotides demonstrates a strong dependence of the complex refractive index on the binding state (hybridized / denatured) of DNA molecules. By monitoring THz transients one can thus infer the binding state of oligo- and polynucleotides. A broadband experimental demonstration in a free-space configuration is presented. The integration into higher-sensitivity approaches in planar structures, as well as the potential application for next generation gene chips are discussed.