Title :
Microinductive Signal Conditioning With Resonant Differential Filters: High-Sensitivity Biodetection Applications
Author :
Baglio, Salvatore ; Pérez-Rodríguez, Alejandro ; Martínez, Susanna ; Serre, Christophe ; Morante, Joan Ramon ; Esteve, Jaume ; Montserrat, Josep
Author_Institution :
Catania Univ., Catania
Abstract :
Inductive-based devices integrated with Si technology for biodetection applications are characterized, using simple resonant differential filter configurations. This has allowed the corroboration of the viability of the proposed circuits, which are characterized by their very high simplicity, for microinductive signal conditioning in high-sensitivity sensor devices. The simulation of these simple circuits predicts sensitivities of the differential output voltage which can achieve values in the range of 0.1-1 V/nH, depending on the coil parameters. These very high-sensitivity values open the possibility for the experimental detection of extremely small inductance changes in the devices. For real microinductive devices, both series resistance and parasitic capacitive components contribute to the decrease of the differential circuit sensitivity. Nevertheless, measurements performed using micro-coils fabricated with relatively high series resistance and coupling parasitic effects have allowed detection of changes in the range of 2 nH. which are compatible with biodetection applications with estimated detection limits below the picomolarity range.
Keywords :
biosensors; magnetic particles; microsensors; passive filters; signal processing equipment; silicon; Si; Si - Element; biodetection application; coupling parasitic effects; differential output voltage; high sensitivity sensor device; immunobiosensors; magnetic immunoassay detectors; magnetic particle detection; microcoil simulation; microinductive signal conditioning; parasitic capacitive components; passive filters; resonant differential filter configurations; series resistance; silicon technology; Biosensors; Circuit simulation; Coils; Filters; Immune system; Integrated circuit technology; Predictive models; Resonance; Sensor phenomena and characterization; Voltage; Detection of magnetic particles; integrated magnetic immunobiosensors; microcoil simulation; microinductive devices; signal conditioning;
Journal_Title :
Instrumentation and Measurement, IEEE Transactions on
DOI :
10.1109/TIM.2007.895593