Fe₃O₄ and TiO₂ nanoparticle-enhanced balangu seed mucilage-gelatin films as advanced functional materials

The present study aimed to develop magnetically and electrically responsive films based on Balangu seed mucilage-gelatin reinforced with Fe₃O₄ nanoparticles (5% and 10%) and TiO₂ nanoparticles (3% and 6%). Results indicated that the incorporation and increased concentration of nanoparticles enhanced film thickness by up to 83%, improved tensile strength and elastic modulus by 29% and 48%, respectively, increased opacity by 471%, and ultimately reduced water vapor and oxygen permeability by 47% and 37%, respectively. Although increasing the nanoparticle concentration reduced the films’ flexibility and biodegradability rate, they retained sufficient flexibility and degraded by more than 75% after 60 days. Enhanced electrical conductivity, antioxidant activity, and antimicrobial properties were also demonstrated, indicating improved functional characteristics of the films upon integration with nanoparticles. FTIR results indicated increased cross-linking and strong molecular interactions between the nanoparticles and the film matrix. Furthermore, XRD results confirmed that the film’s overall crystallinity increased with higher nanoparticle concentrations, in contrast to the control film’s amorphous nature. The interactions between nanoparticles and the biopolymer matrix, along with the hydrophobic nature of the nanoparticles, improved the thermal stability of the films, reduced water solubility, moisture content, and swelling ratio, and rendered the film surface more hydrophobic. FESEM analysis revealed that the film surfaces became slightly rougher and somewhat uneven with the incorporation of nanoparticles. Surface and cross-sectional FESEM images also showed a relatively compact structure with evidence of nanoparticle clustering, which was corroborated by energy-dispersive X-ray spectroscopy (EDX) results. These findings demonstrate the potential of Balangu seed mucilage-gelatin films reinforced with Fe₃O₄ and TiO₂ nanoparticles for advanced applications, including active food packaging, biomedical materials, and intelligent packaging systems.