Electrospun nanofibers of pea protein isolate: Effects of cold plasma treatment on structural, thermal, mechanical,...

This study focuses on the development and enhancement of pea protein isolate (PPI) and polyethylene oxide (PEO) nanofibers treated with cold plasma (CP) to improve drug delivery and antimicrobial properties. Hybrid nanofibers were fabricated by electrospinning with varying PPI:PEO ratios (1:9 to 5:5) and loaded with antimicrobial agents-cinnamon, eugenol, and curcumin (1-10 % w/v). The nanofibers were subjected to CP for 5 min, and their structural and functional properties were evaluated using FTIR, TGA, and DSC. FE-SEM results showed that composite nanofibers based on a PPI:PEO ratio of 1:9, with a combined 10 % loading in water, formed a well-structured matrix. After CP treatment, the 2:8 nanofiber exhibited the highest tensile strength and toughness, whereas the PEO nanofiber showed the most significant improvement in Young's modulus. Regarding water holding capacity (WHC), the 4:6 ratio exhibited the highest increase, with a 3.27 % improvement. In contrast, the most notable reduction in oil holding capacity (OHC) was observed in the 5:5, formulation (3.99 %). Contact angle measurements revealed that the 4:6 ratio had the most pronounced reduction in hydrophobicity, with a 41.34 % decrease. A 5 % concentration of curcumin, eugenol, and cinnamon demonstrated improved cumulative release following CP treatment. The treated nanofibers exhibited strong antimicrobial activity against Escherichia coli. Biodegradation studies indicated that a higher PPI content accelerated degradation. In addition, DPPH assay confirmed enhanced antioxidant activity after CP treatment. These findings suggest that CP-treated PPI:PEO nanofibers are promising for drug delivery and biomedical applications, offering enhanced release profiles, antimicrobial performance, and biodegradability.