A neuronal signal detecting circuit and a neuronal signal stimulating circuit designed for a monolithic integrated MEA（micro-electrode array） system are described. As a basic cell of the circuits, an OPA（ operation...A neuronal signal detecting circuit and a neuronal signal stimulating circuit designed for a monolithic integrated MEA（micro-electrode array） system are described. As a basic cell of the circuits, an OPA（ operational amplifier） is designed with low power, low noise, small size and high gain. The detecting circuit has a chip area of 290 μm × 400 μm, a power dissipation of 2.02 mW, an equivalent input noise of 17.72 nV/ Hz, a gain of 60. 5 dB, and an output voltage from - 2. 48 to ＋ 2. 5 V. The stimulating circuit has a chip area of 130 μm × 290 μm, a power dissipation of 740 μW, and an output voltage from - 2. 5 to 2. 04 V. The parameters show that two circuits are suitable for a monolithic integrated MEA system. The detecting circuit and MEA have been fabricated. The test results show that the detecting circuit works well.展开更多
A microelectrode array（MEA） is presented, which is composed of 60 independent electrodes with 59 working ones and one reference one, and they are divided into 30 pairs. Except for the reference electrode, each pair ...A microelectrode array（MEA） is presented, which is composed of 60 independent electrodes with 59 working ones and one reference one, and they are divided into 30 pairs. Except for the reference electrode, each pair consists of one stimulating electrode and one recording electrode. Supported by the peripheral circuits, four electrode states to study the bioelectrical signal of biological tissue or slice cultured in-vitro on the surface of the electrodes can be realized through each pair of electrodes. The four electrode states are stimulation, recording, stimulation and recording simultaneously, and isolation. The state of each pair of working electrodes can be arbitrarily controlled according to actual needs. The MEAs are fabricated in printed circuit board （PCB） technology. The total area of the PCB-based MEA is 49 mm × 49 mm. The impedance measurement of MEA is carried out in 0.9% sodium chloride solution at room temperature by means of 2-point measurements with an Agilent LCR meter, and the test signal for the impedance measurement is sinusoidal （AC voltage 50 mV, sweeping frequency 20 Hz to 10 kHz）. The electrode impedance is between 200 and 3 kΩ while the frequency is between 500 and 1 000 Hz. The electrode impedance magnitude is inversely proportional to the frequency. Experiments of toad sciatic nerve in-vitro stimulation and recording and signal regeneration between isolated toad sciatic nerves are carried out on the PCB-based MEA. The results show that the MEA can be used for bioelectrical signal stimulation, recording, stimulation and recording simultaneously, and isolation of biological tissues or slices in-vitro.展开更多
Qualitative and quantitative analysis of trace heavy metals in aqueous environment are rapidly assuming significance along with the rapid development of industry.In this paper,gold microelectrode array(MEA)plated with...Qualitative and quantitative analysis of trace heavy metals in aqueous environment are rapidly assuming significance along with the rapid development of industry.In this paper,gold microelectrode array(MEA)plated with mercury film was used for simultaneous voltammetric detection of zinc,cadmium,lead and copper ions in water.The electrochemical behavior and the actual surface area of the MEA were investigated by cyclic voltammetry in K_(3)[Fe(CN)_(6)].Electrochemical impedance spectrum(EIS)was utilized to examine the deposition of mercury on the electrode surface.Based on anodic stripping voltammetry,mercury filmAu MEA was applied to the detection of heavy metals in artificial analyte,where good calibrate linearity was obtained for cadmium,lead and copper ions,but with zinc exhibiting poor linearity.展开更多
In olfactory research, neural oscillations exhibit excellent temporal regularity, which are functional and necessary at thephysiological and cognitive levels. In this paper, we employed a bionic tissue biosensor which...In olfactory research, neural oscillations exhibit excellent temporal regularity, which are functional and necessary at thephysiological and cognitive levels. In this paper, we employed a bionic tissue biosensor which treats intact epithelium as sensing element to record the olfactory oscillations extracellularly. After being stimulated by odorant of butanedione, the olfactory receptor neurons generated different kinds of oscillations, which can be described as pulse firing oscillation, transient firing oscillation, superposed firing oscillation, and sustained firing oscillation, according to their temporal appearances respectively. With a time-frequency analysis of sonogram, the oscillations also demonstrated different frequency properties, such as δ, θ, α, β and γ oscillations. The results suggest that the bionic biosensor cooperated with sonogram analysis can well improve the in- vestigation of olfactory oscillations, and provide a novel model for artificial olfaetion sensor design.展开更多
基金The National Natural Science Foundation of China (No.90307013,90707005)the Natural Science Foundation of Jiangsu Province(No. BK2008032)Open Foundation of State Key Laboratory of Bio-Electronics of Southeast University
文摘A neuronal signal detecting circuit and a neuronal signal stimulating circuit designed for a monolithic integrated MEA（micro-electrode array） system are described. As a basic cell of the circuits, an OPA（ operational amplifier） is designed with low power, low noise, small size and high gain. The detecting circuit has a chip area of 290 μm × 400 μm, a power dissipation of 2.02 mW, an equivalent input noise of 17.72 nV/ Hz, a gain of 60. 5 dB, and an output voltage from - 2. 48 to ＋ 2. 5 V. The stimulating circuit has a chip area of 130 μm × 290 μm, a power dissipation of 740 μW, and an output voltage from - 2. 5 to 2. 04 V. The parameters show that two circuits are suitable for a monolithic integrated MEA system. The detecting circuit and MEA have been fabricated. The test results show that the detecting circuit works well.
基金The National Natural Science Foundation of China(No. 61076118, 90307013, 90707005)the Natural Science Foundation of Jiangsu Province (No. BK2008032)Special Foundation and Open Foundation of the State Key Laboratory of Bioelectronics of Southeast University
文摘A microelectrode array（MEA） is presented, which is composed of 60 independent electrodes with 59 working ones and one reference one, and they are divided into 30 pairs. Except for the reference electrode, each pair consists of one stimulating electrode and one recording electrode. Supported by the peripheral circuits, four electrode states to study the bioelectrical signal of biological tissue or slice cultured in-vitro on the surface of the electrodes can be realized through each pair of electrodes. The four electrode states are stimulation, recording, stimulation and recording simultaneously, and isolation. The state of each pair of working electrodes can be arbitrarily controlled according to actual needs. The MEAs are fabricated in printed circuit board （PCB） technology. The total area of the PCB-based MEA is 49 mm × 49 mm. The impedance measurement of MEA is carried out in 0.9% sodium chloride solution at room temperature by means of 2-point measurements with an Agilent LCR meter, and the test signal for the impedance measurement is sinusoidal （AC voltage 50 mV, sweeping frequency 20 Hz to 10 kHz）. The electrode impedance is between 200 and 3 kΩ while the frequency is between 500 and 1 000 Hz. The electrode impedance magnitude is inversely proportional to the frequency. Experiments of toad sciatic nerve in-vitro stimulation and recording and signal regeneration between isolated toad sciatic nerves are carried out on the PCB-based MEA. The results show that the MEA can be used for bioelectrical signal stimulation, recording, stimulation and recording simultaneously, and isolation of biological tissues or slices in-vitro.
基金This work has been supported by grants from the National Basic Research Program of China(973 program),Grant No.2009CB320303.
文摘Qualitative and quantitative analysis of trace heavy metals in aqueous environment are rapidly assuming significance along with the rapid development of industry.In this paper,gold microelectrode array(MEA)plated with mercury film was used for simultaneous voltammetric detection of zinc,cadmium,lead and copper ions in water.The electrochemical behavior and the actual surface area of the MEA were investigated by cyclic voltammetry in K_(3)[Fe(CN)_(6)].Electrochemical impedance spectrum(EIS)was utilized to examine the deposition of mercury on the electrode surface.Based on anodic stripping voltammetry,mercury filmAu MEA was applied to the detection of heavy metals in artificial analyte,where good calibrate linearity was obtained for cadmium,lead and copper ions,but with zinc exhibiting poor linearity.
基金The National Natural Science Foundation of China，The Research on Public Welfare Technology Application Projects of Zhejiang Province,China，The Zhejiang Provincial Natural Science Foundation of China，The Fundamental Research Funds for the Central Universities
文摘In olfactory research, neural oscillations exhibit excellent temporal regularity, which are functional and necessary at thephysiological and cognitive levels. In this paper, we employed a bionic tissue biosensor which treats intact epithelium as sensing element to record the olfactory oscillations extracellularly. After being stimulated by odorant of butanedione, the olfactory receptor neurons generated different kinds of oscillations, which can be described as pulse firing oscillation, transient firing oscillation, superposed firing oscillation, and sustained firing oscillation, according to their temporal appearances respectively. With a time-frequency analysis of sonogram, the oscillations also demonstrated different frequency properties, such as δ, θ, α, β and γ oscillations. The results suggest that the bionic biosensor cooperated with sonogram analysis can well improve the in- vestigation of olfactory oscillations, and provide a novel model for artificial olfaetion sensor design.
