, Volume 8, Issue 4, pp 34-42

Use of cyclodextrins as a cosmetic delivery system for fragrance materials: Linalool and benzyl acetate

Abstract

The aim of this study was to increase the stability and water solubility of fragrance materials, to provide controlled release of these compounds, and to convert these substances from liquid to powder form by preparing their inclusion complexes with cyclodextrins (CDs). For this purpose, linalool and benzyl acetate were chosen as the fragrance materials. The use of β-cyclodextrin (βCD) and 2-hydroxypropyl-β-cyclodextrin (2-HPβCD) for increasing the solubility of these 2 fragrance materials was studied. Linalool and benzyl acetate gave a B-type diagram with βCD, whereas they gave an AL-type diagram with 2-HPβCD. Therefore, complexes of fragrance materials with 2-HPβCD at 1:1 and 1:2 molar ratios (guest:host) were prepared. The formation of inclusion complexes was confirmed using proton nuclear magnetic resonance (1H-NMR) spectroscopy and circular dichroism spectroscopy. The results of the solubility studies showed that preparing the inclusion complex with 2-HPβCD at a 1:1 molar ratio increased the solubility of linalool 5.9-fold and that of benzyl acetate 4.2-fold, whereas the complexes at a 1:2 molar ratio increased the solubility 6.4- and 4.5-fold for linalool and benzyl acetate, respectively. The stability and in vitro release studies were performed on the gel formulations prepared using uncomplexed fragrance materials or inclusion complexes of fragrance materials at a 1:1 molar ratio. It was observed that the volatility of both fragrance materials was decreased by preparing the inclusion complexes with 2-HPβCD. Also, in vitro release data indicated that controlled release of fragrances could be possible if inclusion complexes were prepared.

Published: October 19, 2007