New Method for Preparing Small-Caliber Artificial Blood Vessel with Controllable Microstructure on the Inner Wall Based on Additive Material Composite Molding

Abstract

The diameter of most blood vessels in cardiovascular and peripheral vascular system is less than 6 mm. Because the inner diameter of such vessels is small, a built-in stent often leads to thrombosis and other problems. It is an important goal to replace it directly with artificial vessels. This paper creatively proposed a preparation method of a small-diameter artificial vascular graft which can form a controllable microstructure on the inner wall and realize a multi-material composite. On the one hand, the inner wall of blood vessels containing direct writing structure is constructed by electrostatic direct writing and micro-imprinting technology to regulate cell behavior and promote endothelialization; on the other hand, the outer wall of blood vessels was prepared by electrospinning PCL to ensure the stability of mechanical properties of composite grafts. By optimizing the key parameters of the graft, a small-diameter artificial blood vessel with controllable microstructure on the inner wall is finally prepared. The corresponding performance characterization experimental results show that it has advantages in structure, mechanical properties, and promoting endothelialization.

Polar-coordinate line-projection light-curing continuous 3D printing for tubular structures

“…Nevertheless, the tubular grafts usually have a large aspect ratio, with tiny tube diameter and long length, making it difficult to stand on the supporting plate stably. To address this problem, researchers have employed the rotating mandrel as the substrate, and used extrusion method to print the filaments onside [34][35][36][37][38]. The inner diameter of the printed vascular shape is determined by the size of rotating mandrel, and the resolution of rotating mandrel-assisted extrusion approach is typically around 0.1 mm, greatly limiting their applications in the microscale blood vessels.…”

Integrated biophysical matching of bacterial nanocellulose coronary artery bypass grafts towards bioinspired artery typical functions

“…Interestingly, technical approaches in (ii) are seemingly much further progressed and provide a variety of structures to hamper the adhesion of thrombotic particles, prevent adverse flow events and guide endothelial colonization 7 – 15 . Consequently, integrated technologies in (i) and (ii) could greatly enhance proceedings towards clinical relevance 9 , 19 , 20 . At this level, biological hydrogels derived by growing bacterial nanocellulose (BNC) biofilms hold a naturally integrative character of both (i) and (ii) in its intrinsic architecture 21 , 22 .This makes it a modular technology that elegantly combines all relevant scaffold properties.…”

“…Basically, the same procedure, but utilizing form giving templates which are mechanically dipped into the culture broth which are then subjected to air incubation at the headspace, to allow the bacteria to transform the wetting into a BNC biofilm, is used to produce tubular BNC nonwovens as vascular scaffolds. This coating technology is called Mobile Matrix Reservor Technology (MMR-Tech) and was developed by Prof. Dieter Klemm (KKF Polymers, Jena, Germany) 19 .…”