Development and characterization of a novel sacrificial core for the fabrication of anatomical polyvinyl alcohol (PVA)-hydrogel-based vascular models for fluid dynamics studies
Year: 2025
Type: article
Abstract: • A novel sacrificial core made of beeswax and paraffin can be melted at 55 °C. • The novel wax-based core enables PVA hydrogel vascular model fabrication. • Core dissolution in mineral oil at 55 °C preserves PVA-H weight and transparency. • Physiological compliance of vascular models supports realistic hemodynamics studies. Patient-specific polyvinyl alcohol hydrogel (PVA-H) vascular models are valuable tools for experimental investigations of vascular diseases and endovascular treatments. However, removing sacrificial cores while maintaining PVA-H structural and mechanical integrity remains challenging. This study aimed to develop and characterize a suitable sacrificial core for fabricating anatomical vascular models for fluid dynamics applications. The effects of different solvents for dissolving sugar- and wax-based sacrificial cores on PVA-H weight, elasticity, and transparency were assessed. Various wax compositions were evaluated for mechanical properties, dimensional retention, and dissolution behavior. Idealized and anatomical aneurysm models were fabricated using selected wax-based core and evaluated for geometric accuracy and compliance. A fluid dynamics feasibility study was performed to assess the effects of a flow diverter (FD) on intra-aneurysmal fluid dynamics. Water, chloroform (CF), and isopropanol (IPA) adversely affected PVA-H properties, whereas mineral oil at 45 °C, 55 °C, and 60 °C preserved the PVA-H weight and transparency, although reducing elasticity. A 1:1 mixture of beeswax and high-melting-point paraffin provided sufficient rigidity to maintain complex vascular geometries with lumens < 2 mm while ensuring dissolution in mineral oil at 55 °C. The fabricated cores showed no significant shrinkage, and compliance values (0.53 ± 0.03 %/mmHg for the idealized and 0.41 ± 0.06 %/mmHg for the anatomical model) were within the physiological range. FD implantation significantly reduced intra-aneurysmal velocity and shifted the inflow jet proximally. This study presents a novel wax-based sacrificial core for fabricating compliant PVA-H vascular models, enabling realistic in vitro fluid dynamics investigations in complex anatomies.
Source: Results in Engineering
Institution: University of Stuttgart
Language: English
Subfield: Molecular Medicine
Domain: Life Sciences
Open Access status: gold
Estimated APC paid: $1,940
OpenAlex ID: W4413919520