Automated fabrication of hydrogel microfibers with tunable diameters for controlled cell alignment.

A newly designed spinning device was utilized to produce continuous hydrogel microfibers with tunable diameters. It was found that the diameter of the microfiber was dependent on perfusion speed and coagulation wheel rotation rate. Their correlation was finally described by a mathematical expression, which proved to be useful for a size-tunable spinning technique. Based on the controllable fabrication of hydrogel microfibers with desired size, microfiber/cell-size-dependent cellular orientated spreading was studied by using PC12 and L929 as model cells. By further demonstrating the assembly of fibrous tissue-like grafts using the spun hydrogel microfibers, the wet spinning protocol was proved to be instructive for manufacturing size-tunable hydrogel microfibers, as well as two-dimensional or three-dimensional scaffolds with varied micro-structure for tissue engineering.