Complexation‐Induced Resolution Enhancement Pleiotropic Small Diameter Vascular Constructs with Superior Antibacterial and Angiogenesis Properties

Abstract

Abstract3D printing has been widely applied for preparing artificial blood vessels, which will bring innovation to cardiovascular disorder intervention. However, the printing resolution and anti‐infection properties of small‐diameter vessels (Φ < 6 mm) have been challenging in 3D printing. The primary objective of this research is to design a noval coaxial 3D printing post‐processing method for preparing small‐size blood vessels with improved antibacterial and angiogenesis properties. The coaxial printing resolution can be more conveniently improved. Negatively charged polyvinyl alcohol (PVA) and alginate (Alg) interpenetrating networks artificial vessels are immersed in positively charged chitosan (CTS) solution. Rapid dimensional shrinkage takes place on its outer surface through electrostatic interactions. The maximum shrinkage size of wall thickness can reach 61.2%. The vessels demonstrate strong antibacterial properties against Escherichia coli (98.8 ± 0.5%) and Staphylococcus aureus (97.6 ± 1.4%). In rat dorsal skin grafting experiments, Cu2+ can promote angiogenesis by regulating hypoxia‐inducible factor‐1 pathway. No artificial blood vessel blockage occur after 5 d of blood circulation in vitro.This article is protected by copyright. All rights reserved

Dynamically Cross-Linked Double-Network Hydrogels with Matched Mechanical Properties and Ideal Biocompatibility for Artificial Blood Vessels

“…Figure 2a displays the tensile stress−strain curves of the five groups of PCO hydrogels, and we can see that the tensile property is significantly influenced by the raw material ratio. As shown in Figure 2b, PCO-2 obtained the highest tensile strength of 0.75 ± 0.04 MPa and a tensile elastic modulus of 0.76 ± 0.02 MPa, being 1.4 times that of pure PVA hydrogel, far exceeding the PVA/alginate/charged chitosan artificial blood vessels 19 and bacterial nanocellulose/chitosan/heparin artificial blood vessels 35 reported to date. The loading− unloading cycling tests for 200 cycles with 20% strain at a constant tensile rate of 100 mm min −1 in Figures 2c, S4, and S5 further demonstrated that PCO-2 hydrogels have ideal elastic recovery, indicating their high tensile mechanical stability and fatigue resistance.…”

“…Xu et al used a bioink mixture of alginate (Alg) and poly(vinyl alcohol) (PVA) for coaxial printing, and then the tube's outer surface was chemically modified with positively charged chitosan (CTS) through electrostatic interactions. 19 The modified PVA artificial blood vessel improved the biocompatibility, and no blockage occurred after 5 days of blood circulation in vitro. Anderson et al grafted the collagen-mimetic peptide onto PVA hydrogel surfaces by CDI chemistry.…”

“…Broadly speaking, there are two major classes of methods designed to enhance the blood compatibility of hydrogels. The first approach is modifying the inert surfaces of hydrogels by a wide variety of methods, such as surface-initiated polymerization, grafting, self-assembly, and surface coating techniques . The second approach is compositing with substances or blending with other bioactive polymers that have good antithrombogenicity and biocompatibility.…”

“…The blood compatibility of hydrogel membranes was significantly improved following the incorporation of heparin-mimicking SSNFs. Xu et al used a bioink mixture of alginate (Alg) and poly­(vinyl alcohol) (PVA) for coaxial printing, and then the tube’s outer surface was chemically modified with positively charged chitosan (CTS) through electrostatic interactions . The modified PVA artificial blood vessel improved the biocompatibility, and no blockage occurred after 5 days of blood circulation in vitro.…”

Customized Vascular Repair Microenvironment: Poly(lactic acid)-Gelatin Nanofibrous Scaffold Decorated with bFGF and Ag@Fe3O4 Core–Shell Nanowires

“…Therefore, the development of novel biodegradable vascular grafts that provide suitable space, allowing cell proliferation, attachment, growth, migration on the scaffold, and subsequent formation of new blood vessels has become a research hotspot. ,− ,, However, novel vascular grafts still face several challenges, including postoperative infection, ,, excessive inflammatory response, , long-term patency, , and lack of nondestructive monitorability. , Significant advancements have been made in the development of a variety of scaffolds with distinct structures and compositions tailored to address the specific challenges mentioned above. For instance, Xu et al fabricated a decellularized CuSO 4 –Alg-PVA-CTS tubular vascular tissue engineering scaffold using coaxial 3D printing and post-treatment, which demonstrated synergistic antibacterial effects due to the release of Cu 2+ ions and the presence of CTS. Furthermore, the Cu 2+ ions were found to enhance EC proliferation and angiogenesis.…”