Intercalation of squalene into h⁺- and al³⁺-exchanged montmorillonite clays and releasing of squalene at simulated gastric conditions
Loading...
Date
2016-11-05
Authors
Bandara, N.C.
Gunasekara, D.U.M.
Bandara, B.M.R.
Journal Title
Journal ISSN
Volume Title
Publisher
University of Peradeniya, Sri Lanka
Abstract
Squalene (C₃₀H₅₀) is a triterpene found abundantly in shark liver oil, in reasonable amounts in amaranth oil and olive oil, and to a lesser extent in other vegetable oils such as corn oil, sunflower oil and soybean oil and in microorganisms. Although squalene (SQ) has various beneficial effects including anticancer, antioxidant and anti-inflammatory properties, its use as a therapeutic drug is limited due to its low bioavailability owing to its lipophilic nature. Incorporation of squalene into the hydrophobic cavity of β-cyclodextrin (β-CD) can yield a composite with a hydrophilic outer coat which can then be intercalated into montmorillonite (MMT) clay’s hydrophilic interlayer nanospace. MMT clays are layered aluminosilicates with expandable interlayer 1-2 nm space, having exchangeable cations between the layers. In this study, intercalation of squalene into cation-exchanged H⁺- and Al³⁺- MMT (Mⁿ⁺-MMT) with and without the assistance of β-CD, and subsequent releasing of squalene from the clay composites at simulated gastric conditions (pH 1.2, 37 ⁰C) were investigated. The cation-exchanged H⁺- and Al³⁺-MMT were prepared by stirring purified Na⁺-MMT clay with aqueous HCl and AlCl₃, respectively. Mn⁺-MMT-β-CD-SQ composites were prepared by mixing SQ, β-CD and Mn⁺-MMT according to three different procedures that differ from one another in the order of mixing the components. All the Mn⁺-MMT clays and the Mn⁺-MMT-β-CD-SQ clay composites were characterized by FTIR and X-ray diffraction techniques. The most effective method was mixing of SQ, β-CD and Mn⁺-MMT together, which afforded more than 80% incorporation of SQ. In the absence of β-CD, SQ loading into Al³⁺-MMT decreased to 66% while that into H⁺-MMT remained almost the same. Releasing studies conducted at simulated gastric conditions with time revealed gradual releasing of SQ, reaching 97% and 100% release from Al³⁺-MMT-β-CD-SQ and H⁺-MMT- CD-SQ composites, respectively, after 6 h. Squalene-intercalation and -release were quantified
using gas chromatography. In conclusion, SQ can be intercalated into cation-exchanged MMT clays and SQ can be slowly released from the clay composites at simulated gastric conditions.
Description
Keywords
Squalene , Shark liver oil , Montmorillonite (MMT)
Citation
Proceedings of the Peradeniya University International Research Sessions (iPURSE) – 2016, University of Peradeniya, P 322