Reading circuit of micro-array biosensor

Abstract

The invention discloses a playback circuit of a micro-array biologic sensor, which includes a buffered output unit, and a current integration unit which is connected with the output terminal of the micro-array biologic sensor and provides a constant bias voltage between the working electrode and the counter electrode of the micro-array biologic sensor, and transforms the current signal from the micro-array biologic sensor into the voltage signal; and a correlated double sampling unit which is connected between the potentiostat current integration unit and the buffered output unit, the voltage signal outputted from the correlated double sampling unit sampling potentiostat current integration unit is denoised and outputted to the buffered output unit. The invention can eliminate the noise signal in the biological microelectrode sensor output signal, and improves the signal-noise ratio of the biological microelectrode sensor output signal.

Description

technical field [0001] The invention relates to a microarray biosensor, in particular to a readout circuit of the microarray biosensor. Background technique [0002] An electrochemical biosensor is a biosensor with an electrochemical signal converter, which is generally considered to be a chemically modified electrode. Electrochemical electrodes are composed of conductive, semiconductor or ion-conductive materials as signal converters, coated with a layer of biochemical or biological film as sensitive elements, and finally the electrical signal is used as a characteristic detection signal. According to the different measurement methods of electrical signals, it can generally be divided into three types: current type, potential type and conductivity type, and current type and potential type are dominant. Due to the shortcomings of traditional chemically modified electrodes such as large volume, low sensitivity, and high noise, chemically modified electrodes for biosensors ar...

AI Technical Summary

Problems solved by technology

Since the readout circuit of the current microarray biosensor basically does not involve noise suppression, the most important noise sources in the readout circuit include 1 / f noise (flicker noise of MOS transistor), KTC noise (reset noise ) and microarray fixed-bias noise signals, these unsuppressed or weakened noise signals V noise (noise signal V noise The sum of all noises in the table) is output to the subsequent circuit along with the readout circuit

Since the front-stage noise signal may be amplified and transmitted to the subsequent stage circuit, the harm is often greater. In order to improve the signal-to-noise ratio of the output signal, it must be eliminated or weakened.

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