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.

Highly osseointegrative dental implants surrounded by reconstructed periodontal tissues represent a promising strategy for functional tooth replacement, as they mimic the structural and physiological characteristics of natural teeth. However, there is currently a lack of in vitro platforms that can effectively evaluate the integration of engineered periodontal ligament (PDL) tissues with bioimplants. In this study, we developed a bioimplant-on-a-chip (BoC) platform designed to recapitulate the native PDL-cementum interface and assess the early stage biological performance of bioimplants in vitro. The BoC consists of a dental implant, a calcium phosphate cement (CPC) insert, a nanopatterned polydimethylsiloxane (PDMS) substrate, and PDL-like tissue derived from human dental pulp stem cells (DPSCs). To establish viable culture conditions within the platform, surface coatings and cell seeding densities were optimized to support the formation of PDL-like tissue. Nanogrooved substrates were incorporated to guide cellular alignment, which was assessed through orientation analysis. Collagen fiber organization and matrix deposition were further examined as indicators of ligamentous tissue maturation. Cementogenic activity was evaluated by immunofluorescent staining of cementum protein-1 (CEMP-1) in response to varying biogenic hydroxyapatite (bHA) contents in the bioimplants. The results demonstrated successful reproduction of a PDL-like tissue interface and material-dependent differences in CEMP-1 expression. This platform provides a modular and reproducible tool for the comparative evaluation of bioimplants in a physiologically relevant setting and may be useful in advancing regenerative strategies in dental implantology.

3D bioprinting creates biological structures by layering bioinks with living cells or biomaterials. Microextrusion, a type of 3D bioprinting, uses pneumatic, piston, or screw methods to extrude bioink precisely. The reliability of 3D bioprinting depends on bioink characteristics, printing conditions, and printer accuracy. Thus, a 3D bioprinter which controls these factors effectively is essential to facilitate 3D bioprinting. In this study, we developed a high-precision 3D bioprinter system (HP-BPS) with high-accuracy 3D plotting system and a screw-based dispenser. Evaluation of reducers installed on the X and Y-axis driving systems decreased motion error by up to 97%. Geometric errors of the HP-BPS were measured using a laser interferometry system. By the application of iterative position error compensation techniques, a position accuracy within ± 2.0 μm was achieved. In the specific carboxymethyl cellulose concentrations (15 and 20%), the HP-BPS could make uncollapsed bioink struts. The HP-BPS successfully fabricated 1 × 1 mm bioscaffold with 0.2 mm struts by the design of experiments and response surface methodology. These results suggest the potential of the HP-BPS for various tissue engineering applications in soft tissue construction, such as skin and blood vessels.