<p>This study investigates the fabrication of a small-diameter bilayer vascular graft, which is an inner layer fabricated from melt-electrowriting (MEW) thermoplastic polyurethane (TPU) scaffold and an outer co-electrospun layer made of heparinized polycaprolactone (PCL)/polyurethane (PU)/gelatin, aimed at mimicking the extracellular matrix (ECM). The bilayer structure exhibited good flexibility, mechanical stability, and anti-thrombogenic properties, overcoming the drawbacks of vascular grafts, such as high kink radius and tendency toward thrombosis. MTT assays proved cytocompatibility, showing an increase in cell proliferation over 7 days, the optical density of the bilayer vascular graft increased from <InlineEquation ID="IEq1"> <InlineMediaObject> <ImageObject Color="BlackWhite" FileRef="41598_2025_10547_Article_IEq1.gif" Format="GIF" Height="14" Rendition="HTML" Resolution="72" Type="Linedraw" Width="107" /> </InlineMediaObject> <EquationSource Format="TEX">\(\:0.347\pm\:0.0065\)</EquationSource> </InlineEquation> on day <InlineEquation ID="IEq2"> <InlineMediaObject> <ImageObject Color="BlackWhite" FileRef="41598_2025_10547_Article_IEq2.gif" Format="GIF" Height="14" Rendition="HTML" Resolution="72" Type="Linedraw" Width="9" /> </InlineMediaObject> <EquationSource Format="TEX">\(\:1\)</EquationSource> </InlineEquation> to <InlineEquation ID="IEq3"> <InlineMediaObject> <ImageObject Color="BlackWhite" FileRef="41598_2025_10547_Article_IEq3.gif" Format="GIF" Height="14" Rendition="HTML" Resolution="72" Type="Linedraw" Width="107" /> </InlineMediaObject> <EquationSource Format="TEX">\(\:0.627\pm\:0.0055\)</EquationSource> </InlineEquation> on day <InlineEquation ID="IEq4"> <InlineMediaObject> <ImageObject Color="BlackWhite" FileRef="41598_2025_10547_Article_IEq4.gif" Format="GIF" Height="14" Rendition="HTML" Resolution="72" Type="Linedraw" Width="9" /> </InlineMediaObject> <EquationSource Format="TEX">\(\:7\)</EquationSource> </InlineEquation>, respectively, due to its fibrous structure and hydrophilic properties. Live/dead and SEM assays confirmed cell viability, attachment, and endothelial layer formation on the scaffold, which provides long-term graft patency. The bilayer graft with integrated MEW structure provided the balanced mechanical and kink-radius properties (ultimate tensile strength <InlineEquation ID="IEq5"> <InlineMediaObject> <ImageObject Color="BlackWhite" FileRef="41598_2025_10547_Article_IEq5.gif" Format="GIF" Height="15" Rendition="HTML" Resolution="72" Type="Linedraw" Width="137" /> </InlineMediaObject> <EquationSource Format="TEX">\(\:7.09\pm\:0.16\:\varvec{M}\varvec{P}\varvec{a}\)</EquationSource> </InlineEquation>, Young’s modulus <InlineEquation ID="IEq6"> <InlineMediaObject> <ImageObject Color="BlackWhite" FileRef="41598_2025_10547_Article_IEq6.gif" Format="GIF" Height="15" Rendition="HTML" Resolution="72" Type="Linedraw" Width="145" /> </InlineMediaObject> <EquationSource Format="TEX">\(\:22.78\pm\:0.91\:\varvec{M}\varvec{P}\varvec{a}\)</EquationSource> </InlineEquation>, suture retention <InlineEquation ID="IEq7"> <InlineMediaObject> <ImageObject Color="BlackWhite" FileRef="41598_2025_10547_Article_IEq7.gif" Format="GIF" Height="15" Rendition="HTML" Resolution="72" Type="Linedraw" Width="114" /> </InlineMediaObject> <EquationSource Format="TEX">\(\:2.13\:\pm\:\:0.09\:\varvec{N}\)</EquationSource> </InlineEquation>) with a low kink radius (<InlineEquation ID="IEq8"> <InlineMediaObject> <ImageObject Color="BlackWhite" FileRef="41598_2025_10547_Article_IEq8.gif" Format="GIF" Height="14" Rendition="HTML" Resolution="72" Type="Linedraw" Width="124" /> </InlineMediaObject> <EquationSource Format="TEX">\(\:9.14\pm\:0.10\:\varvec{m}\varvec{m}\)</EquationSource> </InlineEquation>), surpassing the mechanical properties of coronary artery. A heparin release profile of 70% after 4 weeks was obtained, thus increasing anticoagulant effects. This combination of synthetic (TPU, PCL, PU) and natural (gelatin) polymers yields a biocompatible, structurally stable vascular graft, which efficiently supports endothelialization, and thus has good potential for clinical vascular applications.</p>

错误:搜索内容不能为空,请输入英文关键词
错误:关键词超出字数限制,请精简
高级检索

Fabrication of a low-kink-radius bilayer vascular scaffold incorporating a TPU stent fabricated via melt electrowriting and an electrospun PCL/PU/gelatin layer

  • Mohammad Shahverdi,
  • Hossein Shaygani,
  • Mohamadreza Soltani,
  • Kayvan Dadkhah,
  • Seyed Mohammad Hossein Rezaei Demneh,
  • Kaivan Mohammadi,
  • Amir Shamloo

摘要

This study investigates the fabrication of a small-diameter bilayer vascular graft, which is an inner layer fabricated from melt-electrowriting (MEW) thermoplastic polyurethane (TPU) scaffold and an outer co-electrospun layer made of heparinized polycaprolactone (PCL)/polyurethane (PU)/gelatin, aimed at mimicking the extracellular matrix (ECM). The bilayer structure exhibited good flexibility, mechanical stability, and anti-thrombogenic properties, overcoming the drawbacks of vascular grafts, such as high kink radius and tendency toward thrombosis. MTT assays proved cytocompatibility, showing an increase in cell proliferation over 7 days, the optical density of the bilayer vascular graft increased from \(\:0.347\pm\:0.0065\) on day \(\:1\) to \(\:0.627\pm\:0.0055\) on day \(\:7\) , respectively, due to its fibrous structure and hydrophilic properties. Live/dead and SEM assays confirmed cell viability, attachment, and endothelial layer formation on the scaffold, which provides long-term graft patency. The bilayer graft with integrated MEW structure provided the balanced mechanical and kink-radius properties (ultimate tensile strength \(\:7.09\pm\:0.16\:\varvec{M}\varvec{P}\varvec{a}\) , Young’s modulus \(\:22.78\pm\:0.91\:\varvec{M}\varvec{P}\varvec{a}\) , suture retention \(\:2.13\:\pm\:\:0.09\:\varvec{N}\) ) with a low kink radius ( \(\:9.14\pm\:0.10\:\varvec{m}\varvec{m}\) ), surpassing the mechanical properties of coronary artery. A heparin release profile of 70% after 4 weeks was obtained, thus increasing anticoagulant effects. This combination of synthetic (TPU, PCL, PU) and natural (gelatin) polymers yields a biocompatible, structurally stable vascular graft, which efficiently supports endothelialization, and thus has good potential for clinical vascular applications.