Stabilization strategies in extrusion-based 3D bioprinting for tissue engineering

Three dimensional (3D) printing is a revolutionizing technology, which endows engineers, designers, and manufacturers with the ability to rapidly translate digital sketches into physical objects. The advantages that lie in the high resolution and accuracy of this technique were not concealed from the eyes of tissue engineers that soon harnessed this power for fabrication of complex biological structures. Nevertheless, while the conventional 3D printing scheme is oriented to yield durable and sturdy structures, the delicate nature of the substances used in 3D bioprinting results in fragile and mechanically unstable constructs. This poses a significant restriction that needs to be overcome in order to successfully complete the printing of intact, accurate, and biologically relevant constructs with desirable properties. To address these complications, advanced means of stabilization which are applied during and/or following the printing procedure are constantly being developed. In this review, the rational and principles behind widely used stabilization strategies in extrusion-based bioprinting will be covered. Examples of implementation of these strategies in recently published research in the field of tissue engineering will also be presented and discussed.