Temperature-triggered structural arrangement and properties of transparent pectin-arginine films

Transparent and flexible pectin-arginine films with excellent hemocompatibility and self-healing properties were synthesized using ionotropic gelation at 20 °C or 45 °C to investigate the impact of temperature on their structural arrangement and properties. The degree of amidation increased with synthesis temperature, and Fourier transform infrared (FTIR) spectroscopy and proton nuclear magnetic resonance (¹H NMR) spectroscopy confirmed bond formation between arginine and pectin at both temperatures. Films prepared at two different temperatures exhibited distinct surface hydrophilicity and rheological behaviors. The arginine-based film synthesized at 45 °C (P-AR-45) showed lower surface energy and the most ductile fracture behavior. Scanning electron microscopy revealed that film morphology remained unchanged upon arginine incorporation. Compared to the neat pectin film, arginine-containing films reduced the swelling percentage and water vapor permeability. In vitro tests demonstrated excellent cytocompatibility, efficient wound healing, hemocompatibility, and hemostatic properties. A DPPH test was also conducted to measure the films' antioxidant characteristics, and the radical scavenging activity increased by up to 90% with the addition of arginine. P-AR-45 demonstrated non-irritant properties on the chorioallantoic membrane model while sustaining a maintained vascular response, indicating its potential for further translational evaluation in wound-dressing applications. In addition, in vivo rat liver and tail bleeding models confirmed its hemostatic efficacy. These findings suggest that P-AR-45 is promising candidates for advanced biomedical applications.