TY - JOUR

T1 - Fast Readout of Split-Ring Resonators Made Simple and Low-Cost for Application in HPLC

AU - Hitzemann, Moritz

AU - Dehning, Kirsten J.

AU - Gehl, Adrian V.

AU - Sterr, Erk Fietje

AU - Zimmermann, Stefan

N1 - Acknowledgments: We thank Nic Solle and Christian Beckemeier for their help during this work. We want to acknowledge Martin Lippmann and Cameron Naylor for their advice during editing.

PY - 2022/4/4

Y1 - 2022/4/4

N2 - Split-ring resonators (SRR) are simple electrical circuits that show a significant shift in resonance frequency even with the smallest changes in split capacitance, and thus in permittivity, electric conductivity, and dielectric losses of the split capacitor’s dielectric. Usually, the resonance frequency is derived from the frequency response, but recording the frequency spectrum takes a certain amount of time. Here, we present a new capillary split-ring resonator CaSRR with fast readout for liquid chromatography (LC), which is capable of accurately detecting very fast changes in split capacity. The proposed method is based on the detection of the transmitted signal at a single frequency that is analyzed by demodulation. The demodulated signal changes its amplitude depending on the shift of the resonance frequency. Our simple low-cost electronics enables an average sampling rate of 42 Hz with 128 averages of the demodulated signal and has a frequency stability of 840 mHz. Thus, a minimum change in permittivity of ∆εr,min = 11.26 × 10−3 can be detected. Finally, a chromatogram of one sugar (glucose) and one sugar alcohol (xylitol) is recorded using the SRR and is compared to a standard refractive index detector.

AB - Split-ring resonators (SRR) are simple electrical circuits that show a significant shift in resonance frequency even with the smallest changes in split capacitance, and thus in permittivity, electric conductivity, and dielectric losses of the split capacitor’s dielectric. Usually, the resonance frequency is derived from the frequency response, but recording the frequency spectrum takes a certain amount of time. Here, we present a new capillary split-ring resonator CaSRR with fast readout for liquid chromatography (LC), which is capable of accurately detecting very fast changes in split capacity. The proposed method is based on the detection of the transmitted signal at a single frequency that is analyzed by demodulation. The demodulated signal changes its amplitude depending on the shift of the resonance frequency. Our simple low-cost electronics enables an average sampling rate of 42 Hz with 128 averages of the demodulated signal and has a frequency stability of 840 mHz. Thus, a minimum change in permittivity of ∆εr,min = 11.26 × 10−3 can be detected. Finally, a chromatogram of one sugar (glucose) and one sugar alcohol (xylitol) is recorded using the SRR and is compared to a standard refractive index detector.

KW - demodulator

KW - HPLC

KW - LC

KW - liquid chromatography

KW - readout electronics

KW - split-ring resonator

KW - SRR

UR - http://www.scopus.com/inward/record.url?scp=85127701607&partnerID=8YFLogxK

U2 - 10.3390/electronics11071139

DO - 10.3390/electronics11071139

M3 - Article

AN - SCOPUS:85127701607

VL - 11

JO - Electronics (Switzerland)

JF - Electronics (Switzerland)

SN - 2079-9292

IS - 7

M1 - 1139

ER -