A microfluidic chip for axonal isolation and electrophysiological measurements

Abstract

A microfluidic chip for culturing neurons and spatially isolating axons from somas is presented for use with visually guided whole-cell electrophysiological measurements. A modular design consisting of detachable and re-sealable layers is used to satisfy the requirements of both long-term neuron culturing as well as electrophysiological measurements. Whole cell patch clamp recordings indicate functional viability of neurons with isolated axons. Fluidic isolation was used to achieve asymmetric lentiviral infection of neurons on a single side reservoir. Neurons were asymmetrically infected with lentiviruses expressing the light-activated cationic channel channelrhodopsin-2. Light-evoked excitatory postsynaptic responses were detected by whole cell recordings of neurons on the uninfected side showing functional synaptic connectivity between the two isolated but axonally connected sides of the device.