Interdigitated Capacitive Immunosensors With PVDF Immobilization Layers

Interfacial capacitance immunosensing using interdigitated electrodes: the effect of insulation/immobilization chemistry

“…The "short circuit" problem could be particularly troublesome when using a SAM of alkyl thiols on gold electrodes since small SAM defects can lead to large changes in capacitance or a complete loss of sensitivity 1,17,18 . Furthermore, a variety of architectures have been reported in literature investigating the covalent immobilization of biomolecules on different regions of the sensor such as on the electrodes [6][7][8][9]19 , in the gaps between electrodes 14-16, 20 and a conformal coating covering both 10, 11,21,22 . However, so far, no systematic studies have been performed to evaluate the effect of these architectures on the sensor performance.…”

Iterative Precise Conductivity Measurement with IDEs

“…Using comb-like structures of electrodes (interdigitated electrodes—IDEs) with different sizes is still under intensive research as many published articles in the areas of chemical sensing or characterization [ 1 , 2 , 3 , 4 , 5 , 6 ] and biosensing [ 7 , 8 , 9 , 10 , 11 , 12 , 13 ] have shown this year.…”

Smart and Multifunctional Materials Based on Electroactive Poly(vinylidene fluoride): Recent Advances and Opportunities in Sensors, Actuators, Energy, Environmental, and Biomedical Applications

“…Another glucose sensing device was developed using a capacitive biosensor based on PVDF thin film, consisting of a PVDF film sandwiched between two Ag electrodes. 209 The sensor was evaluated for glucose concentrations in the 0.013− 5.85 M range and various glucose oxidase (GOx) enzyme concentrations between 4882.8 and 2.5 million units•L −1 , reported that the device output increased from 0 to ∼5.5 μV with increasing glucose concentration up to 5.85 M, showing a detection limit of 1.3 × 10 −2 M. Regarding antigen sensing, Sanguino et al 210 reported the use of PVDF Immobilon-P as a sensitive layer coupled with a transducer to function as affinity immunosensors, able to distinguish phosphate-buffered saline (PBS) buffer and antigen horseradish peroxidase (HRP) solutions, based on the capacitance variations (PBS, 0 to −0.6 pF; and HRP, 0 to 0.1 pF). Such measurements could be taken at a fixed frequency, making the sensor instrumentation particularly simple and easily scalable for practical applications such as clinical diagnosis, food monitoring, industrial controls, and environmental measurements.…”