Printable smart 3D architectures of regenerated silk on poly(3-hydroxybutyrate-co-3-hydroxyvalerate)

In this study, we report the fabrication of two different three-dimensional (3D) architectures of regenerated silk (RS) and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) with embedded functionalities. 3D printed cylinders with an internal layer of PHBV and an external of calcium ions (Ca++) or potassium nitrate (KNO3) modified RS were designed to control the radial shrinkage, water uptake and compression strength. Such cylinders were then used as sutureless thermoresponsive clips, measuring the bursting resistance once applied on an anastomized porcine intestine. Experimental data are supported by finite element simulations that model the tube contraction, demonstrating the possibility to program the shape-changing behavior of 3D printed structures. Printing RS on PHBV, we obtained responsive 3D grids to external force with self-powering properties. The synergic effect obtained by combining materials on appropriate architectures paves the way to potential clinical applications ranging from monitoring of vital signs to sutureless sealant patches. [Display omitted] •3D printing of hybrid natural proteins and bio-based polymers•Digitally designed 3D objects with self-powering properties•Modeling the different thermal coefficient of expansion of the protein layer onto a biopolymer•Engineering strategy to seal an anastomosis without the aid of mechanical sutures