Heterogeneously integrated impedance measuring system with disposable thin-film electrodes

Abstract

a b s t r a c tWe propose a novel integrated impedance measurement system with disposable thin-film electrodes. Most modern CMOS-based biosensors use on-chip electrodes to interface between the electronics and biosamples, which forces disposal of the CMOS chip after a few measurements, since most biological reactions are non-reversible. The sensor performance is also limited by the design of on-chip electrodes due to the physical dimensions and the CMOS design rules restrictions. In this work, we extract the electrodes from the silicon chip for relocation onto a low-cost, disposable substrate. This enables reusability of the high-performance CMOS chip, at the same time providing a low-cost route for manufacture of the active thin-film electrodes using large-area processing. The use of disposable thin-film chip also enables customised designed electrodes for different applications, such as extra high sensitivity concentration sensors. In this work, DNA concentration measurements are performed, and it shows a doubling of sensitivity over the previously reported system.

Impedance Estimation Read-out System for Biomedical Sensors

“…This paper has demonstrated an impedance estimation read-out system with the widest frequency region, the least impedance and phase error, which is justified by Table III [9][10][11]. By integrating BIA technique with the read-out IC system, we find a better, more reliable, and quicker solution on rapid diagnostic test on cancer biomarkers.…”

An impedance-based chemiresistor for the real-time detection of gut microbiota-generated short-chain fatty acids

“…The maximum value of phase angle (40°) occurred in the frequency range of 10 3 to 10 4 Hz, suggesting the frequency dispersion and the interfacial heterogeneity of the sensing layer [54]. The value of phase angle suggests that the capacitive behaviour of the sensing layer acts as an open-circuit and equals the source voltage [55]. In addition, the magnitude of the impedance gradually increased, as a common impedance response in faradaic probes.…”

“…The copyright holder for this preprint this version posted September 13, 2022. ; https://doi.org/10.1101/2022.09.11.507374 doi: bioRxiv preprint [55]. In addition, the magnitude of the impedance gradually increased, as a common impedance response in faradaic probes.…”

Inkjet-printed Ag electrodes on paper for high sensitivity impedance measurements

“…As shown in Fig. 1a, all electrodes were surrounded by a PDMS ring to contain the electrolyte, and they were connected to an customized impedance measurement system 35 . An AC signal with the amplitude of 100 mV was used with the frequencies ranging from 10 Hz to 10 MHz.…”