Vascular stenting is a common procedure used to treat diseased blood vessels by opening the narrowed vessel lumen and restoring blood flow to ischemic tissues in the heart and other organs. In this work, we report a novel piezoelectric stent featuring a zigzag shape fabricated by fused deposition modeling three-dimensional (3D) printing with a built-in electric field. The piezoelectric composite was made of potassium sodium niobite microparticles and poly(vinylidene fluoride-co-hexafluoropropylene), complementing each other with good piezoelectric performance and mechanical resilience. The in situ poling yielded an appreciable piezoelectricity (d33 ∼ 4.2 pC N-1) of the as-printed stents. In vitro testing revealed that materials are nontoxic to vascular cells and have low thrombotic potential. Under stimulated blood pressure fluctuation, the as-printed piezoelectric stent was able to generate peak-to-peak voltage from 0.07 to 0.15 V corresponding to pressure changes from 20 to 120 Psi, giving a sensitivity of 7.02 × 10-4 V Psi-1. Biocompatible piezoelectric stents bring potential opportunities for the real-time monitoring of blood vessels or enabling therapeutic functions.
Keywords: 3d printing; blood pressure sensing; energy harvesting; piezoelectricity; stents.