DISSOCIATED NEURONAL CULTURES

Our high density microelectrode array, also known as multielectrode array (HD-MEA), chips can be implemented in different ways to gather high-resolution electrophysiological data from large networks of cultured neurons. Experimenters can filter the activity of spontaneous and chemically induced spatiotemporal patterns, watch the neural network’s response to stimuli and even study complex network topologies, just to name a few examples.

Spontaneous activity

200 ms of spontaneous electrophysiological activity of hippocampal cell cultures (22 days in vitro) showing sustained burst propagations over the whole network.

Low density culture

100 ms of spontaneous electrophysiological activity of hippocampal cell cultures (15 days in vitro) seeded at a low cellular density in order to resolve cellular activity (~4,000 neurons).

Electrical stimulation

Recording of electrically evoked responses (100 ms) of a cultured hippocampal network (days in vitro) using two (A, B) different on-chip stimulating electrodes. Even responses below 3 ms can be recorded without electrically induced artifacts.

3D culture

Spiking activity recorded from primary cortical neuronal culture at DIV 25 with a 3D scaffolding.

Low density culture

Two different examples (A and B) of different activity patterns recorded from the same hippocampal culture (22 DIV) from a 2-day old post-natal rat.

Data provided courtesy of Mariateresa Tedesco, from Prof. Sergio Martinoia's lab, DIBRIS, University of Genova, Italy.

BRAIN TISSUES

Both field potentials and multi-unit activities can be sensed in unprecedented spatiotemporal detail on our microelectrode arrays (HD-MEAs). The large field of view on our HD-MEAs enables assays on large tissue portions, such as rat cortico-hippocampal slices or brain organoids, to be carried out.

Cerebellar slice

Cerebellar slice recording from a mouse (21 days old), showing spontaneous electrophysiological activity in Purkinje cells.

Epileptic-like events

Functional imaging of distinct inter-ictal (I-IC) events obtained by superimposing the activity recorded from a cortico-hippocampal slice by 3Brain's high-resolution CMOS-MEA with the image of the slice itself taken by a microscope.

Rat cortico-hippocampal

Recording of a rat hippocampal slice (14 days old) during spontaneous activity (A) and after perfusion with 4-Aminopyridine (B immediately after; C: 15 min after perfusion).

Data provided courtesy of Franco Ortiz, from Prof. Rafael Gutiérrez's lab, Centro de Investigación y Estudios Avanzados del Insituto Politecnico Nacional, Mexico.

Mouse hippocampal

Recording of hippocampal activation from two different mice, respectively 21 (A) and 27 (B) post-natal days, under perfusion with 4-Amino-Pyridine.

ACUTE RETINA

Our high-density microelectrode array, or multielectrode arrays (HD-MEAs) are ideal for investigating explanted retinas, thanks to their large-scale sensing areas (up to 5.12 x 5.12 mm2) that feature a temporal resolution which outperforms more traditional imaging techniques.

Dystrophic retina

Recording of spontaneous electrophysiological activity from the ganglion cell layer in the Cone Rod Homeobox knockout mouse retina, a model of photoreceptor dystrophy. Dystrophic retinas are characterized by pathological, strong spontaneous bursting and oscillations in the ganglion cell layer. In this example, bursts are generated in cell bodies and propagate along axons converging toward the optic disc.

Spontaneous waves

Spontaneous waves recorded from the ganglion cell layer in a P11 mouse retina. The activity becomes stronger in the presence of the GABA-A receptor antagonist bicuculline (10 µM) and furosemide (100 µM), a blocker of the potassium-chloride co-transporter KCC2.

Light stimulation

Light-elicited ganglion cell responses of a mouse retina (P113) showing the activity of retinal ON ganglion cells after onset of a full field light stimulus (2.8 cd*s/m2). Immediately after stimulus onset, ON transient ganglion cell types respond to the light followed by more ON sustained ganglion cell types. The optic disc is in the middle, the dorsal side at the bottom and the ventral side at the top.

Axonal responses

Retinal ganglion cell axonal responses to flickering (1Hz) checkerboard stimulus under dark mesopic conditions. The recording clearly shows propagating impulses along axonal bundles (P113 days mouse).

Data provided courtesy of Dr. Evelyne Sernagor and Dr. Gerrit Hilgen, The Institute of Neuroscience (ION), NewCastle upon Tyne, UK.

Salamander retina

Recording of light-elicited activity of salamander retinal ganglion cells.

Data provided courtesy of Dr. Tim Gollisch and Dr. Vidhyasankar Krishnamoorthy, University Medical Center Göttingen, Dept. of Ophthalmology, Göttingen, Germany.