Multifrequency Investigation of Single- and Double-Stranded DNA with Scalable Metamaterial-Based THz Biosensors

Due to the occurrence of THz-excited vibrational modes in biomacromolecules, the THz frequency range has been identified as particularly suitable for developing and applying new bio-analytical methods. We present a scalable THz metamaterial-based biosensor being utilized for the multifrequency investigation of single- and double-stranded DNA (ssDNA and dsDNA) samples. It is demonstrated that the metamaterial resonance frequency shift by the DNA's presence depends on frequency. Our experiments with the scalable THz biosensors demonstrate a major change in the degree of the power function for dsDNA by 1.53 +/- 0.06 and, in comparison, 0.34 +/- 0.11 for ssDNA as a function of metamaterial resonance frequency. Thus, there is a significant advantage for dsDNA detection that can be used for increased sensitivity of biomolecular detection at higher frequencies. This work represents a first step for application-specific biosensors with potential advantages in sensitivity, specificity, and robustness.

Automated summary

THz frequency range is considered suitable for developing new bio-analytical methods due to the presence of THz-excited vibrational modes in biomacromolecules. In this study, a scalable THz metamaterial-based biosensor was used to investigate DNA samples at multiple frequencies. The results showed that the resonance frequency shift of the metamaterial depended on the presence of DNA and varied with frequency. The experiments demonstrated a significant difference in the power function between dsDNA and ssDNA, indicating an advantage for dsDNA detection and increased sensitivity at higher frequencies.