Evaluation of osteogenic differentiation of human mesenchymal stem cells (hMSCs) on random and aligned polycaprolactone-polyaniline-gelatin scaffolds

Biocompatible and biodegradable scaffolds have gained tremendous attention because of their potential in tissue engineering. In this study, the aim was to reach a feasible setup from a ternary hybrid of polyaniline (PANI), gelatin (GEL), and polycaprolactone (PCL) to fabricate aligned and random nanofibrous scaffolds by electrospinning for tissue engineering purposes.

Different setups of PANI, PCL, and GEL were electrospun. Then, the best aligned and random scaffolds were chosen. SEM imaging was done to observe nanoscaffolds before and after stem cell differentiation. Mechanical properties of the fibers were tested. Their hydrophilicity was measured using the sessile drop method. SNL Cells were then seeded onto the fiber, and MTT was performed to assess its toxicity. The cells were then differentiated. After osteogenic differentiation, alkaline phosphatase activity, calcium content assay, and alizarin red staining were done to check the validity of osteogenic differentiation.

The two chosen scaffolds had an average diameter of 300 ± 50 (random) and 200 ± 50 (aligned). MTT was performed and its results showed that the scaffolds were non-toxic to cells. After stem cell differentiation, alkaline phosphatase activity was performed, confirming differentiation on both types of scaffolds. Calcium content and alizarin red staining also confirmed stem cell differentiation. Morphological analysis showed no difference regarding differentiation on either type of scaffold. However, unlike on the random fibers, cells followed a specific direction and had a parallel-like growth pattern on aligned fibers.

All in all, PCL-PANI-GEL fibers showed to be capable candidates for cell attachment and growth. Furthermore, they proved to be of excellent use in bone tissue differentiation.