Gelatin Blends Enhance Performance of Electrospun Polymeric Scaffolds in Comparison to Coating Protocols

Abstract

The electrospinning of hybrid polymers is a versatile fabrication technique which takes advantage of the biological properties of natural polymers and the mechanical properties of synthetic polymers. However, the literature is scarce when it comes to comparisons of blends regarding coatings and the improvements offered thereby in terms of cellular performance. To address this, in the present study, nanofibrous electrospun scaffolds of polycaprolactone (PCL), their coating and their blend with gelatin were compared. The morphology of nanofibrous scaffolds was analyzed under field emission scanning electron microscopy (FE-SEM), indicating the influence of the presence of gelatin. The scaffolds were mechanically tested with tensile tests; PCL and PCL gelatin coated scaffolds showed higher elastic moduli than PCL/gelatin meshes. Viability of mouse embryonic fibroblasts (MEF) was evaluated by MTT assay, and cell proliferation on the scaffold was confirmed by fluorescence staining. The positive results of the MTT assay and cell growth indicated that the scaffolds of PCL/gelatin excelled in comparison to other scaffolds, and may serve as good candidates for tissue engineering applications.

Keywords: PCL; characterization; electrospinning; gelatin; mechanical properties; scaffold; tissue engineering.

Figure 1

Home-made electrospinning setup.

Figure 2

FE-SEM micrographs of electrospun scaffolds: (A,D) PCL 10%, (B,E) PCL 10% with gelatin coating, (C,F) PCL 20%: gelatin 8% (80:20). Scale bar: 10 μm (A–C); 2 μm (D–F).

Figure 3

(A) Example of mechanical behavior of the scaffolds. (B) Boxplot of different materials showing the elastic modulus of PCL, PCL gelatin coating and PCL/gelatin 80:20 (** p < 0.05).

Figure 4

FT-IR of (A) PCL 10% scaffold (B) PCL 10% with gelatin coating and (C) PCL/gelatin 80:20 composite scaffold.

Figure 5

MTT results of MEF on the PCL, PCL gelatin coating and PCL/gelatin nanofibers after 24, 48 and 72 h.

Figure 6

SEM images showing attachment of MEF on the surface of the scaffolds after 72 h: (A,D) PCL 10%, (B,E) PCL 10% with gelatin coating, (C,F) PCL 20%: gelatin 8% (80:20). Scale bar: 10 μm (A–C); 2 μm (D–F).

Figure 7

MEF proliferation study on the PCL, PCL gelatin coating and PCL/gelatin blend for 24, 48 and 72 h. (Green) Actin filaments of MEF stained with Phalloidin AlexaFluor 488. (Blue) DAPI staining the nucleus. Scale bar: 20 μm.