An Interesting Limitation on Application of THz Spectroscopy to Characterization of DNA

THz (terahertz) spectroscopy has been proposed as a novel method to characterize DNA molecules when applied on plasmonic surfaces. This approach can be used as a less expensive alternative for a DNA characterization method. It has been successfully demonstrated that a significant shift of the resonant frequency in THz spectrum between TRIS buffer and TRIS buffer containing the DNA can be observed. The sensitivity of the method can be enhanced when the resonant frequency of the DNA molecule under consideration matches the plasmon frequency of the plasmon surface yielding a non-linear effect of overlapping resonances. It is shown here that this method only works when the THz radiation is applied above certain energy threshold.

Keywords: THz spectroscopy; Plasmon surfaces; DNA characterization

Abbreviations: THz: Terahertz; TDS: Time Domain Spectroscopy; DNA: Deoxyribonucleic acid; FFT: Fast Fourier Transform