This paper presents a switched-capacitor (SC) current integrator circuit for impedance measurement of tethered bilayer lipid membrane (tBLM) biosensors. The circuit comprises a small number of high performance components enabling enhanced experimental flexibility and reliability. The sensitivity is improved significantly by suppressing the output offset through pseudo-differential operation, using R-C components for the reference impedance. The sensing and reference electrodes are excited with low-amplitude differential voltage pulses and the current response to membrane resistance (RM) change of the tBLM biosensor is converted to voltage by a precision, low-noise SC integrator available as a single-package IC. Tests with both electrical models and actual biosensors demonstrated that the proposed circuit operates with high sensitivity and can be used in single chip versions for low-cost and high-sensitive tBLM biosensor arrays, featuring multiple electrode sites.
Temiz Y., Gurkaynak F.K., Terrettaz S., Vogel H., De Micheli G., Leblebici Y., et al. (2008). Real-time high-sensitivity impedance measurement interface for tethered BLM biosensor arrays. NEW YORK : IEEE Press.
Real-time high-sensitivity impedance measurement interface for tethered BLM biosensor arrays
GUIDUCCI, CARLOTTA;BENINI, LUCA
2008
Abstract
This paper presents a switched-capacitor (SC) current integrator circuit for impedance measurement of tethered bilayer lipid membrane (tBLM) biosensors. The circuit comprises a small number of high performance components enabling enhanced experimental flexibility and reliability. The sensitivity is improved significantly by suppressing the output offset through pseudo-differential operation, using R-C components for the reference impedance. The sensing and reference electrodes are excited with low-amplitude differential voltage pulses and the current response to membrane resistance (RM) change of the tBLM biosensor is converted to voltage by a precision, low-noise SC integrator available as a single-package IC. Tests with both electrical models and actual biosensors demonstrated that the proposed circuit operates with high sensitivity and can be used in single chip versions for low-cost and high-sensitive tBLM biosensor arrays, featuring multiple electrode sites.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
