Label-free detection of biomaterials using terahertz technology

We present terahertz (THz) absorption spectra of various biomolecules (tripeptide gly-gly-gly and oligo-nucleotides poly[A] and poly[C]). While the tripeptide shows unique resonances in the THz range due to intramolecular vibrations, the different oligo-nucleotides can be distinguished due to different absorption properties. In space-resolved THz free-space measurements, we were able to repeatedly distinguish between dried drops of poly[A] and poly[C]. In addition, we present the design for a new class of filters for on-chip analysis of biomaterials. As compared to filters described earlier in the literature, the new structures have an increased sensitivity and require much less biomaterial.