Enhancement of hydrophilicity, biocompatibility and biodegradability of poly(ε-caprolactone) electrospun nanofiber scaffolds using poly(ethylene glycol) and poly(L-lactide-co-ε-caprolactone-co-glycolide) as additives for soft tissue engineering

Abstract

In this study, poly(ε-caprolactone) (PCL) has been blended with a more hydrophilic poly(ethylene glycol) (PEG) and with a biocompatible block-co-polymer: poly(L-lactide-co-ε-caprolactone-co-glycolide) (PLCG) in order to improve hydrophilicity, biocompatibility and biodegradability of PCL. PCL and the blend solutions were subjected to electrospinning to produce nanofiber scaffolds by the addition of only 1 wt% of PEG and PLCG either singly or in combination in PCL to retain the mechanical properties of the scaffolds. PCL-PEG-PLCG ternary and two binary (PCL-PEG and PCL-PLCG) blend nanofiber scaffolds have been prepared for comparison. The resulting nanofibers showed a smooth and flaw-free surface and the diameter of the nanofibers displayed a normal distribution. The PCL-PEG nanofiber scaffold showed improved hydrophilicity [water contact angle (WCA) ∼84°] over pristine PCL (WCA ∼127°); while PCL-PLCG and PCL-PEG-PLCG scaffolds exhibited absolute wetting by water, likely due to high porosity. In vitro biocompatibility studies using gingival mesenchymal stem cells (gMSCs) suggested that, both the PCL and the blend scaffolds were biocompatible supporting cell-viability and growth of gMSCs following their seeding on these scaffolds. Biodegradation studies in phosphate buffer solution showed that the addition of PEG and PLCG in PCL increased the weight loss of scaffolds with time, indicating higher extent of biodegradation in the blend scaffolds and the weight loss followed the power law curve with time.

Keywords:

• Poly(ε-caprolactone)
• poly(L-lactide-co-ε-caprolactone-co-glycolide)
• polyethylene glycol
• nanofiber scaffolds
• hydrophilicity
• biocompatibility

Acknowledgements

The authors would like to thank Dr. Praveen Kumar, ARDE-DRDO, Pune for extending SEM characterization facility, Dr. Manjushree Bahir, NCCS for help during cell culture experiments, and Dr. S. Bose and Ms. Aishwarya Menon, IISc, Bangalore for fruitful technical discussion. The authors would like to thankfully acknowledge Dr. Sangram Rath, NMRL for technical discussion. GKA would like to gratefully acknowledge DIAT for providing his PhD research fellowship. TUP would like to acknowledge financial support from DIAT (DU).

Disclosure statement

No potential conflict of interest was reported by the author.