FIG. 1.

Schematics of haptotaxis assay for neurite growth. (A) Isoparametric view of the microfluidic approach used to generate gradients. An H-shaped network is placed on an underlying network comprising a small well connected to a straight channel. The underlying network is pre-filled with collagen and a dorsal root ganglion explant is placed in the well. Peptide-grafted collagen solution is pumped into the source channel and untreated collagen solution into the sink channel to generate a gradient in the cross-channel. This gradient is immobilized upon self-assembly of the collagen into a fibrillar network. (B) Top view depicting neurite growth in the assay. A sub-population of neurites enter the cross-channel. Neurite growth is quantified by counting the number and the average length of processes that grow up or down the gradient. Modified with permission from figure originally published in Sundararaghavan et al., 2009.