Photomanipulation using holographic illumination
Together with Rapp OptoElectronic we developed a setup combining two-photon imaging with two-photon photomanipulation. The use of a spatial light modulation (SLM) enables the generation of arbitrary patterns in 3D for the photomanipulation. These patterns can be changed rapidly, making it particularly useful for the interrogation of neuronal circuits. Photomanipulation of neurons can be realized by using caged neurotransmitters or genetically encoded modulators of neuronal activity ("optogenetics"). The setup is complemented by a sensitive sCMOS cameras (for samples not requiring two-photon excitation, such as cell cultures) and a patch-clamp setup.
Local activation of synaptic responses in a cultured neuron using caged glutamate. Several locations of the cell can be stimulated in sequence or simultaneously.
Neuronal activity can be induced by stimulating cells expressing the optogenetic activator ReaChR, and at the same time read-out optically by using the Ca2+-indicator GCaMP6s in a mouse brain slice.