Comparison of the surface properties and cytocompatibility between plasma activated and homogeneously polydopamine-coated PCL nanofibers as a result of a pre-plasma activation step

Plasma activation and polydopamine (PDA) coating deposition on nanofibrous tissue engineering (TE) scaffolds have emerged as two easy and inexpensive methods to improve their cell-material interactions. This work is the first one to compare the cytocompatibility of both surface modification techniques on polycaprolactone nanofibers (NFs). First, the argon plasma treatment (PT) and PDA coating deposition were optimized based on water contact angle (WCA) measurements and visual observation, respectively. It was shown that employing the optimized PT before the PDA layer deposition enables a more homogeneous PDA deposition in comparison to the untreated counterpart. Subsequently, scanning electron microscopy showed that the treatments did not damage the fibers. X-ray photoelectron spectroscopy indicated that the PT resulted in the introduction of O-containing functionalities, while the PDA coating introduced a complex C-, N-, and O-based chemistry. The changed surface chemistry also led to a significant increase in wettability for both surface treatments in comparison to the untreated NFs. Different human foreskin fibroblast-based cell tests indicated that the PDA coating outperformed the PT with regard to cell adhesion and proliferation, although the latter still resulted in a significant improvement in comparison to the untreated NFs. Thereby, this study indicates that a careful surface modification selection is necessary to obtain the desired performance of TE scaffolds.

Automated summary

Plasma activation and polydopamine coating deposition are easy and inexpensive methods to improve cell-material interactions on tissue engineering scaffolds. This study compares their cytocompatibility on polycaprolactone nanofibers and finds that polydopamine coating performs better in terms of cell adhesion and proliferation, although plasma activation also shows improvement compared to the untreated fibers.