Fabrication of vascular tissue engineering scaffolds with enhanced oxygen diffusivity and cell attachment and proliferation

Sonia Abbasi ravasjani,1 Ghassem amoabediny,2,* Mohammadreza safari hajat aghaei,3 Amir esmaeili,4 farideh hajiani,5 Javad mohammadnejad,6

1. Faculty of New Sciences and Technologies, University of Tehran, Tehran, Iran
2. School of chemical Engineering, College of Engineering, University of Tehran, Tehran, Iran
3. Faculty of New Sciences and Technologies, University of Tehran, Tehran, Iran
4. School of chemical Engineering, College of Engineering, University of Tehran, Tehran, Iran
5. Faculty of Applied Arts, Textile and Clothing Design, University of Art, Tehran, iran
6. Faculty of New Sciences and Technologies, University of Tehran, Tehran, Iran

Abstract


Introduction

Increased oxygen diffusivity through three dimensional porous scaffolds and surface hydrophilicity of the scaffolds are important requirements to successfully fabricate engineered tissue construct.

Methods

In this study tubular and disk shaped polycaprolactone (pcl) scaffolds for vascular tissue engineering applications were fabricated by electrospinning method with different syringe flow rates (0.5, 1, 1.5ml/h). the morphology and diameter of the nanofibers were examined by scanning electron microscopy (sem). liquid displacement method was used to measure the porosity of the scaffolds. to measure effective oxygen diffusion coefficient of the scaffolds, an experimental apparatus was constructed. oxygen concentration was measured with dissolved oxygen micro sensor. type i collagen was immobilized on the nanofibers after surface modification with sodium hydroxide. human umbilical vein endothelial cells were cultured on the luminal surface of the tubular scaffolds up to 7 days. alamar blue assay was performed to evaluate the metabolic activity of the cells.

Results

Sem image analysis showed increase in fiber diameter from 200-250nm up to 300-350nm by increasing in syringe flow rate from 0.5ml/h to 1.5ml/h. porosity measurement showed decrease in overall porosity of the scaffolds from 77.86% to 54.98% by increasing the syringe flow rate. effective oxygen diffusion coefficient of the scaffolds decreased from 5.33e-5 cm/s2 to 4e-6 cm/s2 by increasing fiber diameter from 200-250nm to 300-350nm. metabolic activity of cells was significantly higher on the collagen immobilized scaffolds compared to other groups.

Conclusion

The results showed that fiber diameter of the electrospun scaffolds influences their effective oxygen diffusion coefficient and collagen attachment enhances cellular metabolic activity.

Keywords

Effective oxygen diffusion coefficient, fiber diameter, scaffold porosity, collagen immobilization