Chlorogenic acid-loaded sandwich-structured nanofibrous film developed by solution blow spinning: Characterization, release behavior and antimicrobial activity

In this work, solution blow spinning (SBS) was used to rapidly develop a sandwich-structured nanofibrous film with an outer layer of polyurethane (PU) nanofibers and an inner layer of polyvinylpyrrolidone (PVP) nanofibers with chlorogenic acid (CGA) loading. Scanning electronic microscopy images showed that there were clear boundaries between the inner and outer layers. The hydrogen bonds that formed between the two layers enhanced the thermal stability. Compared to the CGA-loaded film, the sandwich structure increased the elongation at break and tensile strength from 3.01 ± 0.97% to 201.34 ± 9.63% and 0.0120 ± 0.0002 MPa to 0.1569 ± 0.0117 MPa, respectively, and the PU layer endowed the sandwich-structured film with hydrophobic surfaces. Furthermore, the sandwich structure shifted the burst release of the CGA-loaded film to a long-term sustained release within 144 h. In addition, the sandwich-structured film retained the antioxidant and antimicrobial activities of CGA. These results indicated that the sandwich-structured nanofibrous film developed by SBS possesses potential applications in food packaging.