Effect of thermal treatments and UV radiation on green soy protein isolated crosslinked electrospun mats

Plant-derived proteins continue to draw great interest due to their high availability, biodegradability, and biological properties. Among them, soy protein isolate (SPI) has been explored for the development of different sustainable and biodegradable materials in many bionanotechnological fields. In addition, the electrospinning technique has gained interest as a versatile platform for designing synthetic/biopolymer-based nanofibrous mats for a huge variety of bionanotechnological fields. However, the water stability of SPI mats is low, and the sterilization procedures and conditions are not well established. In this work, oxidized sucrose (OS) was used as a green and inexpensive crosslinker for electrospun SPI mats. The sugar oxidation process was optimized by varying hydrogen peroxide concentration and reaction temperature. SPI-OS solutions were electrospun using acetic acid as a benign solvent and the resulting mats were thermally treated at mild temperatures and different times. The crosslinked structures were fully characterized in terms of fiber morphology, and physicochemical and thermal properties. Interestingly, uniform bead-free nanofibrous SPI-OS membranes that retained their fibrous morphology after 7 days of immersion in phosphate-buffered saline were successfully obtained. In addition, bilayered SPI-OS/polycaprolactone mats were also produced by green electrospinning and sterilized by UV radiation for different exposure times. Finally, the effect of sterilization on the relevant properties was presented and discussed. UV radiation demonstrated to be an effective method for sterilizing crosslinked SPI-based nanofibrous structures.

Automated summary

Plant-derived proteins, especially soy protein isolate (SPI), have gained considerable attention in bionanotechnological applications due to their high availability, biodegradability, and biological properties. Electrospinning is a versatile technique for designing nanofibrous mats, but the water stability and sterilization of SPI mats needs improvement. In this study, oxidized sucrose was used as a green and low-cost crosslinker for electrospun SPI mats, resulting in bead-free and water-stable nanofibrous membranes. Sterilization by UV radiation was found to be effective for sterilizing the crosslinked SPI-based nanofibrous structures.