Fuente: Journal of applied polymer Lugar: RESEARCH ARTICLE Zn(II)-coordinated PEI/PAN nanofibrous membranes with synergistic antimicrobial activity effectively preserve strawberries at room temperature, offering a green alternative to chemical preservatives for perishable fruits.

ABSTRACT
Long-term preservation of fresh fruits and vegetables without cold chain support remains a critical bottleneck in ensuring food safety, primarily due to their high susceptibility to deterioration under ambient indoor storage conditions. Herein, a multifunctional Zn(II)-coordinated polyacrylonitrile (PAN) and polyethyleneimine (PEI) nanofibrous composite membranes (PAN-PEI-Zn) with efficient antimicrobial activity and breathability was rationally designed and fabricated via PEI grafting onto electrospun PAN nanofibrous scaffolds, followed by Zn(II) coordination modification. Compared with pristine commercial PAN films, the as-fabricated PAN-PEI-Zn membranes exhibited high antimicrobial rate (> 99.99%) against both Gram-negative bacteria Escherichia coli and Gram-positive bacteria Staphylococcus aureus. Notably, in contrast to commercially available PE cling films, the PAN-PEI-Zn membranes demonstrated excellent hydrophilicity and favorable breathability. Furthermore, PAN-PEI-Zn membranes also possessed superior physical properties tailored for food packaging applications. Freshness preservation experiments confirmed that the PAN-PEI-Zn membranes could extend the shelf life of strawberries by 7 days, while significantly suppressing fruit rotting and water loss. This advanced PAN-based preservation membranes holds great promise for enhancing the quality of agricultural products, prolonging food shelf life, and reducing the reliance on energy-intensive cold chain transportation. This work offers a feasible strategy for PAN-based nanofibrous composite membranes in antibacterial and food preservation.