Antimicrobial peptide (AMP) coatings are a promising strategy to prevent bacterial adhesion on medical devices. Here, the AMP KR-12 was immobilized on textured silicone breast implants to impart antibacterial functionality. Oxygen plasma treatment generated surface silanol groups that promoted peptide attachment through hydrogen bonding. FTIR spectroscopy confirmed KR-12 immobilization by detecting the characteristic amide I band. Molecular dynamics simulations supported the stability of the implant–KR-12 interface, while release studies revealed an initial lag phase (6.63 h) followed by sustained peptide release reaching approximately 10 μg/cm2 after 48 h. COMSOL Multiphysics simulations suggested the formation of a multilayered KR-12 coating (73 nm), consistent with the observed controlled-release behavior. Functionalized implants exhibited strong antibacterial activity, achieving nearly 100 % bacterial inhibition of Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus epidermidis, and approximately 90 % inhibition of Staphylococcus aureus. Cytocompatibility assays showed no adverse effects on mammalian cells. Altogether, these plasma-assisted KR-12 coatings on textured silicone achieve nearly complete bacterial inhibition and sustained release, validated through an integrated experimental and computational approach, highlighting the potential of this strategy to reduce implant-associated infections.
This study reports the fabrication of porous polycaprolactone/polyethylene glycol/polylactic acid (PCL/PEG/PLA) scaffolds by solvent casting/particulate leaching for localized doxorubicin (DOX) delivery. PEG content was kept constant, while the PCL/PLA ratio was varied to tune scaffold wettability, swelling, surface energy, drug loading, and release behavior. The scaffolds were characterized by scanning electron microscopy, Fourier-transform infrared spectroscopy, swelling tests, water contact angle measurements, Zisman surface-energy analysis, DOX loading, and in vitro DOX release. SEM revealed porous morphologies with pore sizes ranging from 580 nm to 27 µm, and FTIR confirmed the characteristic bands of PCL, PEG, and PLA. DOX loading decreased from 19 ± 1 % to 12 ± 8 % as the water contact angle increased from 67.58 ± 0.42° to 78.73 ± 0.49°. DOX release showed an initial burst followed by slower release up to 720 h.
This study investigates the influence of talc particle reinforcement on the rheological, mechanical, and vibration behavior of stereolithography (SLA) photopolymer composites. Talc particles with an average size of 1–5 µm were incorporated into the resin at weight ratios of 10 wt% and 20 wt%. Rheological results show an increase in viscosity and shear-thinning behavior with increasing talc content. Mechanical characterization indicates enhanced stiffness and compressive strength, accompanied by reductions in tensile strength, toughness, and hardness, indicating increased brittleness. Vibration analyses were also carried out on the composite specimens. Based on free vibration testing, the damping ratio increased by approximately 7 % and 16 % for the 10 wt% and 20 wt% talc-reinforced specimens, respectively. On the other hand, an indirect estimate derived from normalized viscosity data yielded smaller increases of approximately 5 % and 8 % for the same compositions. The results indicate a clear correlation between vibration behavior and rheological characteristics.
Lightweight and broadband microwave absorbing materials are essential for advanced stealth applications. In this study, RPUF composites incorporating multi-component microwave-absorbing fillers were prepared. A functionally graded structure was designed by integrating GFRP as the panel and CFRP as the backing layer. The optimized composite demonstrated excellent mechanical properties and effective absorption performance, achieving a reflection loss below −10 dB across the 8–18 GHz band. Experimental results closely aligned with simulation predictions, confirming the effectiveness of the structural design. This work offers a viable strategy for developing high-performance, lightweight absorbing materials suitable for such applications.
Ulcerative colitis (UC) is a chronic inflammatory bowel disease associated with oxidative stress and mucosal inflammation. Curcumin (Cur) shows promise for UC management, but its poor aqueous solubility and instability in the gastrointestinal tract lead to low oral bioavailability and limited therapeutic efficacy. In this study, curcumin-loaded ROS-responsive nanoparticles (HSNPs@Cur) were developed based on diselenide-modified hyaluronic acid (HA-Se) to improve the stability and oral delivery of Cur. HSNPs@Cur exhibited good stability under different temperatures, pH, and storage conditions, indicating that nanoencapsulation effectively protected Cur under non-oxidative conditions. In the presence of H2O2, HSNPs@Cur showed ROS-responsive behavior and rapidly released Cur within 8 h. In addition, HSNPs@Cur demonstrated significant antioxidant and anti-inflammatory activities in vitro, likely owing to the combined contribution of Cur bioactivity and diselenide-bond-mediated ROS responsiveness. HSNPs@Cur exhibited good hemocompatibility, cytocompatibility, and in vivo biocompatibility following oral administration, with no obvious systemic toxicity or histopathological abnormalities observed in major organs. These results provide preliminary evidence that HSNPs@Cur represents a stable and biocompatible ROS-responsive oral nanocarrier with potential to improve the stability and oral delivery of Cur for UC-related applications.
