Multifrequency WGM Resonator Approach for Study of DNA Solutions with Reduced Microwave Screening

This work presents a new approach for studies of DNA molecules with reduced microwave screening using a developed multifrequency Whispering Gallery Mode resonator technique. The proof-of-principle of the suggested method is demonstrated by utilizing a plastic layer with a microfluidic channel containing nanoliter volumes of liquid. The authors demonstrate the effectiveness of this method for detecting DNA molecules in frozen samples. The key innovations of the study are considerably reduced losses due to phase transition in DNA solutions with temperature decreasing and the application of a multifrequency approach. Precise measurements of shifts in the resonant frequency and Q-factor changes, simultaneously taken at six frequencies reveal clear investigation of DNA molecules. This approach opens new opportunities for efficient and accurate DNA analysis using microwave sensors in scientific and diagnostic fields.