High performance bio-based hyperbranched polyurethane/carbon dot-silver nanocomposite: a rapid self-expandable stent

Area of Science:

• Biomaterials Science
• Nanotechnology
• Polymer Chemistry

Background:

• Developing high-performance, biocompatible, and antibacterial implantable materials is crucial for biomedical applications.
• Drug-resistant bacteria pose a significant challenge, necessitating novel antimicrobial strategies.
• The bio-nano interface offers opportunities for creating advanced smart materials.

Purpose of the Study:

• To fabricate starch-modified hyperbranched polyurethane (HPU) nanocomposites incorporating carbon dot-silver nanohybrids.
• To evaluate the structural, mechanical, thermal, and shape-memory properties of the developed nanocomposites.
• To assess the in vitro cytocompatibility, hemocompatibility, and antibacterial efficacy against resistant bacterial strains.

Main Methods:

• In situ polymerization of starch-modified HPU with varying wt.% of carbon dot-silver nanohybrid.
• Characterization using TEM, XRD, FTIR, EDX, and thermal analysis.
• In vitro biological assessments including cell proliferation, platelet adhesion, RBC hemocompatibility, and antibacterial assays.

Main Results:

• Nanocomposites with 5 wt.% nanohybrid showed a 1.7-fold increase in tensile strength and 1.5-fold increase in toughness.
• Exceptional shape recovery (99.6%) and self-expansion (>99%) within 20s at 37°C were observed.
• The nanocomposites demonstrated excellent in vitro cytocompatibility, hemocompatibility, and significant antibacterial activity against E. coli and S. aureus.

Conclusions:

• The developed HPU nanocomposites offer a promising combination of mechanical strength, rapid self-expansion, and infection resistance.
• These materials exhibit favorable biological interactions, supporting cell growth and reducing platelet adhesion.
• The study highlights the potential of these nanocomposites as advanced, infection-resistant, self-expandable stents for endoscopic surgeries.