Do the cells sit on top of the silk?

Contrary to many other 3D scaffolds where the cells are seeded onto an already formed 3D network, cells can be mixed in the Biosilk solution prior to the silk network formation. That means that the newly formed silk fibers will encapsulate the cells and the cells will be evenly distributed throughout the 3D matrix. As a result of the air bubbles present during the formation, this 3D structure will also be porous, allowing for much larger contact with nutrients and oxygen in the media.