Electrospun nanofibers from cyclodextrin inclusion complexes with cineole and p-cymene: Enhanced water solubility and thermal stability

The electrospinning of self-standing nanofibrous webs from inclusion complexes (IC) of cineole and p-cymene with two modified cyclodextrins (HPβCD, HPγCD) was achieved without using carrier polymeric matrix. Although they are highly volatile, certain amount of cineole and p-cymene was protected in cyclodextrin inclusion complexes nanofibers (CD-IC-NF). That is, 68.4%, 78.1%, 54.5% and 44.0% (w/w) of active agent were preserved in cineole/HPβCD-IC-NF, cineole/HPγCD-IC-NF, p-cymene/HPβCD-IC-NF and p-cymene/HPγCD-IC-NF, respectively. Remarkable, high thermal stability for cineole (~150 °C - 270 °C) and p-cymene (~150 °C - 275 °C) was achieved for CD-IC-NF samples due to CD-IC formation. The water solubility of cineole and p-cymene was significantly improved by inclusion complexation where CD-IC-NF samples become readily dissolved in water. In brief, essential oils and flavours such as cineole and p-cymene could be applicable in food and oral care applications owing to their fast-dissolving behaviour along with high water solubility, enhanced thermal stability and free-standing feature of CD-IC-NF webs.