4D Printing of Shape Memory Vascular Stent Based on βCD‐g‐Polycaprolactone

• Published in: Macromolecular rapid communications. 2021-07, Vol.42 (14), p.e2100176-n/a
• Main Authors: Zhou, Yanyi, Zhou, Dong, Cao, Pengrui, Zhang, Xinrui, Wang, Qihua, Wang, Tingmei, Li, Zhaolong, He, Wenyang, Ju, Junping, Zhang, Yaoming
• Format: Article
• Language: English
• Subjects: 4D printing; Biocompatibility; biocompatible stents; Bursting pressure; Cell adhesion; Crosslinking; Cyclodextrin; Cyclodextrins; drug loaded polymers; Endothelial cells; Implants; Ischemia; Paclitaxel; Polycaprolactone; Polymerization; Polymers; Ring opening polymerization; Shape memory; shape memory polymers; Stents; Tensile strength; Ultraviolet radiation; Umbilical vein; Wettability
• ISSN: 1022-1336; 1521-3927
• DOI: 10.1002/marc.202100176

The 4D‐printing technology is applied to fabricate a shape memory peripheral stent with good biocompatibility, which sustains long‐term drug release. The star polymer s‐PCL is prepared by ring opening polymerization of ε‐caprolactone with the ‐OH of β‐cyclodextrin (βCD) as initiator, and then the s‐PCL is modified with acrylate endgroup which allows the polymerization under UV light to form the crosslinking network c‐PCL. Attributed to the feature of the high crosslinked structure and chemical nature of polycaprolactone (PCL) and βCD, the composite exhibits appropriate tensile strength and sufficient elasticity and bursting pressure, and it is comparable with great saphenous vein in human body. The radial support of the 4D‐printed stent is 0.56 ± 0.11 N and is equivalent to that of commercial stent. The cell adhesion and proliferation results show a good biocompatibility of the stent with human umbilical vein endothelial cells. Due to the presence of βCD, the wettability and biocompatibility of the materials are improved, and the sustained paclitaxel release based on the host–guest complexion shows the potential of the drug‐loaded stent for long‐term release. This study provides a new strategy to solve the urgent need of small‐diameter scaffolds to treat critical limb ischemia. In this paper, the star polymer s‐PCL (polycaprolactone) is prepared by ring open polymerization of ε‐caprolactone (ε‐CL) and β‐cyclodextrin (β‐CD), and then is modified with acrylate which allows the polymerization under UV light. The designed material possesses good biocompatibility and mechanical support properties, which suggests that it has the potential to synthesize new small‐caliber vascular stents.