Enhanced biocompatibility and endothelialization of silk fibroin-derived peptide-based coating for cardiovascular tissue engineering applications.

Polycaprolactone (PCL) has emerged as a promising biomaterial for artificial heart applications due to its biodegradability and mechanical properties. However, its hydrophobic nature and limited biocompatibility pose challenges for cardiovascular applications, requiring optimal cell-material interactions. This study investigates the surface modification of silk fibroin-derived peptide/PCL coatings to enhance biocompatibility and cellular response for potential artificial heart applications. PCL substrates were blended with varying concentrations of silk fibroin-derived peptide (0.2%, 0.5%, and 1% w/v). Surface characterization was performed using water contact angle measurements, Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy. Biocompatibility was evaluated through cell viability assays and CD31 expression analysis. Silk fibroin-derived peptide incorporation significantly improved surface hydrophilicity, with contact angles decreasing from 78° (bare PCL) to 62° (1% silk fibroin-derived peptide). FTIR analysis confirmed successful incorporation of silk fibroin-derived peptides, showing characteristic PCL ester C=O absorption at ∼1720 cm-1 and concentration-dependent amide I contributions at ∼1630-1670 cm-1. Cell viability studies demonstrated enhanced cellular response with increasing silk fibroin-derived peptide concentration, particularly evident at day 7. CD31 expression analysis revealed improved endothelial marker expression, with the highest levels observed on 1% silk fibroin-derived peptide-incorporated substrates. The results demonstrate that silk fibroin blended to PCL significantly enhances biocompatibility through improved hydrophilicity and cellular interactions. Taken together, these preliminary results indicate that silk fibroin-derived peptide-incorporated PCL could represent a promising biomaterial platform for artificial heart applications, with the potential to improve endothelial compatibility and support endothelialization.