Using the compartmentalized microfluidic chamber, we sought to compartmentalize two distinct populations of neurons, facilitating the visualization of synapses between them. The microfluidic chamber consists of 2 main compartments (1,500 μm wide, 100 μm high) which are connected by ∼150 parallel microgrooves (7.5 μm wide, 900 μm long, 3 μm high) (Figure 1A). Dissociated neurons are plated in each compartment and cultured, during which time processes emanating from the cell bodies grow into the microgrooves and into the adjacent compartment (without the addition of growth factors) (Figure 1B). While axonal growth within microgrooves is well-documented (Taylor et al., 2005), the growth of dendrites within the microgrooves has not been characterized.
