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A low-noise, modular, and versatile analog front-end intended for processing in vitro neuronal signals detected by microelectrode arrays.

Regalia G, Biffi E, Ferrigno G, Pedrocchi A - Comput Intell Neurosci (2015)

Bottom Line: To address this issue, we developed a custom MEA interfacing system featuring low noise, low power, and the capability to be readily integrated inside an incubator-like environment.Two stages, a preamplifier and a filter amplifier, were designed, implemented on printed circuit boards, and tested.The system is characterized by a low input-referred noise (<1 μV RMS), a high channel separation (>70 dB), and signal-to-noise ratio values of neuronal recordings comparable to those obtained with the benchmark commercial MEA system.

View Article: PubMed Central - PubMed

Affiliation: Neuroengineering and Medical Robotics Laboratory, Electronics, Information and Bioengineering Department, Politecnico di Milano, 20133 Milan, Italy.

ABSTRACT
The collection of good quality extracellular neuronal spikes from neuronal cultures coupled to Microelectrode Arrays (MEAs) is a binding requirement to gather reliable data. Due to physical constraints, low power requirement, or the need of customizability, commercial recording platforms are not fully adequate for the development of experimental setups integrating MEA technology with other equipment needed to perform experiments under climate controlled conditions, like environmental chambers or cell culture incubators. To address this issue, we developed a custom MEA interfacing system featuring low noise, low power, and the capability to be readily integrated inside an incubator-like environment. Two stages, a preamplifier and a filter amplifier, were designed, implemented on printed circuit boards, and tested. The system is characterized by a low input-referred noise (<1 μV RMS), a high channel separation (>70 dB), and signal-to-noise ratio values of neuronal recordings comparable to those obtained with the benchmark commercial MEA system. In addition, the system was successfully integrated with an environmental MEA chamber, without harming cell cultures during experiments and without being damaged by the high humidity level. The devised system is of practical value in the development of in vitro platforms to study temporally extended neuronal network dynamics by means of MEAs.

No MeSH data available.


Related in: MedlinePlus

Scheme of the assembled setup showing the disposition of the custom preamplifier board (inside a PMMA-made MEA chamber), the custom filter amplifier board, the A/D device, and the power supply (Multi Channel Systems GmbH). The preamplifier PCB contacts the MEA pads by means of gold spring contacts (schematized by the gold arrows).
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fig4: Scheme of the assembled setup showing the disposition of the custom preamplifier board (inside a PMMA-made MEA chamber), the custom filter amplifier board, the A/D device, and the power supply (Multi Channel Systems GmbH). The preamplifier PCB contacts the MEA pads by means of gold spring contacts (schematized by the gold arrows).

Mentions: The boards were manufactured using standard PCB technology. The preamplifier board has been designed with Altium Designer (Altium Ltd.), obtaining a four-layer layout (Figures 3(a) and 3(b)). The size of the board has been set to 65 × 85 mm. A squared 33 × 33 mm hole has been located in the center of the board, matching the size of standard glass or plastic culture containers coupled to MEA substrates (Multi Channel Systems GmbH). Along the edge of the hole, 60 miniaturized gold spring contacts (RS Components Ltd.) have been inserted through appropriate holes to vertically contact the MEA pads by pressure (Figures 3(a) and 4). The presence of the hole ensures the maximum physical proximity between pads and electronics. Operational amplifiers were chosen with a miniaturized, dual channel surface mounted package (OPA2376, M-SOP8 package), while passive components package was set to 0201, to reduce the physical occupation of the parts. On the top layer (red in Figure 3(b)), components (preamplifiers and voltage regulators) and ground plane were located; on the layer beneath (blue) traces for half the output signals were drawn, while the remaining ones were put on the other middle layer (green), together with the power supply traces; the bottom layer (brown) was filled with a ground plane. Output signals and power supply traces are organized in a 64-pin, 1.27-pitch, double row output connector (Figure 3(a)).


A low-noise, modular, and versatile analog front-end intended for processing in vitro neuronal signals detected by microelectrode arrays.

Regalia G, Biffi E, Ferrigno G, Pedrocchi A - Comput Intell Neurosci (2015)

Scheme of the assembled setup showing the disposition of the custom preamplifier board (inside a PMMA-made MEA chamber), the custom filter amplifier board, the A/D device, and the power supply (Multi Channel Systems GmbH). The preamplifier PCB contacts the MEA pads by means of gold spring contacts (schematized by the gold arrows).
© Copyright Policy - open-access
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC4419262&req=5

fig4: Scheme of the assembled setup showing the disposition of the custom preamplifier board (inside a PMMA-made MEA chamber), the custom filter amplifier board, the A/D device, and the power supply (Multi Channel Systems GmbH). The preamplifier PCB contacts the MEA pads by means of gold spring contacts (schematized by the gold arrows).
Mentions: The boards were manufactured using standard PCB technology. The preamplifier board has been designed with Altium Designer (Altium Ltd.), obtaining a four-layer layout (Figures 3(a) and 3(b)). The size of the board has been set to 65 × 85 mm. A squared 33 × 33 mm hole has been located in the center of the board, matching the size of standard glass or plastic culture containers coupled to MEA substrates (Multi Channel Systems GmbH). Along the edge of the hole, 60 miniaturized gold spring contacts (RS Components Ltd.) have been inserted through appropriate holes to vertically contact the MEA pads by pressure (Figures 3(a) and 4). The presence of the hole ensures the maximum physical proximity between pads and electronics. Operational amplifiers were chosen with a miniaturized, dual channel surface mounted package (OPA2376, M-SOP8 package), while passive components package was set to 0201, to reduce the physical occupation of the parts. On the top layer (red in Figure 3(b)), components (preamplifiers and voltage regulators) and ground plane were located; on the layer beneath (blue) traces for half the output signals were drawn, while the remaining ones were put on the other middle layer (green), together with the power supply traces; the bottom layer (brown) was filled with a ground plane. Output signals and power supply traces are organized in a 64-pin, 1.27-pitch, double row output connector (Figure 3(a)).

Bottom Line: To address this issue, we developed a custom MEA interfacing system featuring low noise, low power, and the capability to be readily integrated inside an incubator-like environment.Two stages, a preamplifier and a filter amplifier, were designed, implemented on printed circuit boards, and tested.The system is characterized by a low input-referred noise (<1 μV RMS), a high channel separation (>70 dB), and signal-to-noise ratio values of neuronal recordings comparable to those obtained with the benchmark commercial MEA system.

View Article: PubMed Central - PubMed

Affiliation: Neuroengineering and Medical Robotics Laboratory, Electronics, Information and Bioengineering Department, Politecnico di Milano, 20133 Milan, Italy.

ABSTRACT
The collection of good quality extracellular neuronal spikes from neuronal cultures coupled to Microelectrode Arrays (MEAs) is a binding requirement to gather reliable data. Due to physical constraints, low power requirement, or the need of customizability, commercial recording platforms are not fully adequate for the development of experimental setups integrating MEA technology with other equipment needed to perform experiments under climate controlled conditions, like environmental chambers or cell culture incubators. To address this issue, we developed a custom MEA interfacing system featuring low noise, low power, and the capability to be readily integrated inside an incubator-like environment. Two stages, a preamplifier and a filter amplifier, were designed, implemented on printed circuit boards, and tested. The system is characterized by a low input-referred noise (<1 μV RMS), a high channel separation (>70 dB), and signal-to-noise ratio values of neuronal recordings comparable to those obtained with the benchmark commercial MEA system. In addition, the system was successfully integrated with an environmental MEA chamber, without harming cell cultures during experiments and without being damaged by the high humidity level. The devised system is of practical value in the development of in vitro platforms to study temporally extended neuronal network dynamics by means of MEAs.

No MeSH data available.


Related in: MedlinePlus