Antioxidant vitamin E/cyclodextrin inclusion complex electrospun nanofibers: enhanced water solubility, prolonged shelf life, and photostability of vitamin E
Here, we demonstrated the electrospinning of polymer-free nanofibrous webs from inclusion complex (IC) between hydroxypropyl-β-cyclodextrin (HPβCD) and Vitamin E (Vitamin E/HPβCD-IC NF). The inclusion complexation between HPβCD and Vitamin E was prepared by using two different molar ratios (Vitamin E/HPβCD; 1:2 and 1:1), which correspond to theoretical value of ∼13% (w/w) and 26% (w/w) loading of Vitamin E in the nanofiber (NF) matrix. After electrospinning and storage, a very high loading of Vitamin E (up to ∼11% w/w, with respect to fiber matrix) was preserved in Vitamin E/HPβCD-IC NF. Because of the cyclodextrin inclusion complexation, only a minimal weight loss (only ∼2% w/w) was observed. While pure Vitamin E is insoluble in water, Vitamin E/HPβCD-IC NF web has displayed fast-dissolving behavior. Because of the greatly enhanced water-solubility of Vitamin E, Vitamin E/HPβCD-IC NF web has shown effective antioxidant activity. Additionally, Vitamin E/HPβCD-IC NF web has provided enhanced photostability for the sensitive Vitamin E by the inclusion complexation in which Vitamin E/HPβCD-IC NF still kept its antioxidant activity even after exposure to UV-light. Moreover, a 3 year-old Vitamin E/HPβCD-IC NF sample has shown very similar antioxidant efficiency when compared with freshly prepared Vitamin E/HPβCD-IC NF indicating that long-term stability was achieved for Vitamin E in the CD-IC fiber matrix. In brief, our results suggested that polymer-free electrospun Vitamin E/HPβCD-IC nanofibrous webs could have potential applications in food, pharmaceuticals, and healthcare thanks to its efficient antioxidant activity along with enhanced water-solubility, prolonged shelf life, and high photostability of Vitamin E.