Cell-printed hierarchical scaffolds consisting of micro-sized polycaprolactone (PCL) and electrospun PCL nanofibers/cell-laden alginate struts for tissue regeneration.

Hierarchical scaffolds consisting of micro-sized struts with inter-layered nanofibers between the struts are mechanically stable and biologically superior to conventionally fabricated rapid-prototyped scaffolds and electrospun nanofibers. However, although the hierarchical scaffolds overcome various disadvantages of conventional scaffolds, there are still some limitations, such as low cell migration in the thickness direction and non-homogeneous cell proliferation. To overcome these deficiencies, a new hierarchical scaffold supplemented with osteoblast-like cell (MG63)-laden alginate struts is proposed. To control cell proliferation in the thickness direction of the scaffold, the density of interlayered nanofibers was manipulated using various electrospinning deposition times (2, 5, 10, and 20 s). Using the appropriate interlayered fiber density (electrospin deposition time = 10 s) and cell-laden alginate struts, we can obtain significantly homogeneous cell distribution in the hierarchical scaffold.