Functional electrospun polymeric nanofibers incorporating geraniol-cyclodextrin inclusion complexes: High thermal stability and enhanced durability of geraniol

- Solid geraniol/CD-IC were successfully prepared by using α-CD, β-CD and γ-CD.
- γ-CD was found the most proper CD for the complexation with more amount geraniol.
- Geraniol/γ-CD-IC was incorporated into PVA NF via electrospinning.
- Higher thermal stability of geraniol was observed in PVA/geraniol/γ-CD-IC NF.
- Prolonged durability of geraniol in PVA/geraniol/γ-CD-IC NF was provided by CD-IC.

In this study, solid geraniol/cyclodextrin inclusion complexes (geraniol/CD-IC) were successfully prepared by using three types of native CD (α-CD, β-CD and γ-CD). The modeling studies for inclusion complexation between CD and geraniol were performed by using ab initio techniques. Both experimentally and theoretically, the complexation efficiency between geraniol and γ-CD was higher; therefore, geraniol/γ-CD-IC was chosen and then incorporated into polyvinyl alcohol (PVA) nanofibers (NF) via electrospinning. The scanning electron microscopy imaging elucidated that the aggregates of geraniol/γ-CD-IC crystals were distributed in the PVA NF, whereas bead-free and uniform PVA and PVA/geraniol NF without CD-IC were obtained. Higher thermal stability of geraniol was observed in the electrospun PVA/geraniol/γ-CD-IC NF. However, geraniol molecules having volatile nature could not be preserved without CD-IC during electrospinning or during storage; therefore, the complete evaporation of geraniol in PVA/geraniol NF was unavoidable even after one day of its production. On the contrary, the loss of geraniol was minimal (~ 10%) for PVA/geraniol/γ-CD-IC NF even after storage of these NF for two years owing to inclusion complexation. Our study demonstrated that electrospun NF incorporating CD-IC may be quite applicable in food industry, e.g.: active food packaging or functional foods, due to very high surface area and nanoporous structure of NF; high thermal stability and enhanced durability of active agents and functional food ingredients.