Development of a gelatin-based polyurethane vascular graft by spray, phase-inversion technology

Abstract

The capacity of a composite vascular graft constituting polyurethane (PU) and gelatin to support cell growth was investigated using human mesenchymal stem cells (hMSCs). Gelatin-based polyurethane grafts were fabricated by co-spraying polyurethane and gelatin using a spray, phase-inversion technique. Graft microstructure was investigated by light and scanning electron microscopy. Uniaxial tensile tests were performed to assess the grafts' mechanical properties in longitudinal and circumferential directions. hMSCs obtained from bone marrow aspirate were seeded onto flat graft samples. After 24, 48, and 72 h of incubation, cell morphology was evaluated by Giemsa staining and cell viability was calculated by XTT assay. SEM analysis evidenced that PU samples display a microporous structure, whereas the gelatin-based PU samples show a fibrillar appearance. The presence of cross-linked gelatin produced a significant increase of ultimate tensile strength and ultimate elongation in circumferential directions compared to PU material. Qualitative analysis of hMSC adhesion onto the grafts revealed remarkable differences between gelatin-based PU and control graft. hMSCs grown onto gelatin-based PU graft form a monolayer that reached confluence at 72 h, whereas cells seeded onto the control graft were not able to undergo appropriate spreading. hMSCs grown onto gelatin-based PU graft showed significantly higher viability than cells seeded onto bare PU at all time points. In conclusion, a composite vascular graft was successfully manufactured by simultaneous co-spraying of a synthetic polymer and a protein to obtain a scaffold that combines the mechanical characteristics of polyurethanes with the favorable cell interaction features of gelatin.

Development and Realization of an Experimental Bench Test for Synchronized Small Angle Light Scattering and Biaxial Traction Analysis of Tissues

“…Even if the presented technique was designed for mechano-biological analysis for soft biological tissues, its customizability allows the usage in other biomedical fields, such as vascular grafts and cardiovascular valves prostheses [48,49]. The results derived from this approach will permit to quantify and interpret the effect of fiber distribution for mechanical constitutive modeling [43].…”

Modification of relevant polymeric materials for medical applications and devices

“…There exist other studies about modified PU with different polymers, such as acrylic acid (AAc) (Butruk-Raszeja, Trzaskowska, Kuźminska, & Ciach, 2016;Myung et al, 2005), gelatin (Losi et al, 2015), 2-hydroxyethyl acrylate (HEA) (Guan et al, 2000), poly(ethylene oxide) (Han, Park, & Kim, 1998) and polydimethylsiloxane (Pinchuk, Martin, Esquivel, & Macgregor, 1988;Shourgashti et al, 2010), used for medical applications. As it is the case of the HEA grafted PU were proved as scaffold for the promotion of human endothelial cell adhesion and growth.…”

State of the Art of Small‐Diameter Vessel‐Polyurethane Substitutes

“…However, the degradation rate of PEU with conventional structure was slow, so adjusting the PEU biodegradability to satisfy the requirements of scaffolds becomes of research interest. Besides the factors mentioned above, such as type of materials, molecular weight, amphiphilicity, and steric effect, which are in view of the chemical structures of PEU, simple and effective blending is now the popular method to tune PEU biodegradability . For example, Hinrichs et al blended PEU with polycaprolactone or polylactic acid separately in light of their biodegradable characteristics and fabricated two kinds of blended PEU vascular scaffolds (PEU/polycaprolactone and PEU/polylactic acid) .…”