Cyclodextrin-based Pickering emulsions: functional properties and drug delivery applications

Abstract

Cyclodextrins (CDs) are biocompatible, cyclic oligosaccharides that are widely used in various industrial applications and have intriguing interfacial science properties. While CD molecules typically have low surface activity, they are capable of stabilizing emulsions by inclusion complexation of oil-phase components at the oil/water interface, which results in Pickering emulsion formation. Such surfactant-free formulations have gained considerable attention in recent years, owing to their enhanced physical stability, improved tolerability, and superior environmental compatibility compared to conventional, surfactant-based emulsions. In this review, we critically describe the latest insights into the molecular mechanisms involved in CD stabilization of Pickering emulsions, including covering practical aspects such as methods to prepare CD-based Pickering emulsions, lipid encapsulation, and relevant stability issues. In addition, the rheological and textural features of CD-based Pickering emulsions are discussed and particular attention is focused on promising examples for drug delivery, cosmetic, and nutraceutical applications. The functionality of currently developed CD-based Pickering emulsions is also summarised, including examples such as antifungal uses, and we close by discussing emerging possibilities to utilize the molecular encapsulation of CD-based emulsions for translational medicine applications in the antiviral and antibacterial spaces.

Drug-Loaded Nanocarriers Composed of Cholesteryl Oleate Crystal Cores and Multiple-Nanosheet Shells of γ-Cyclodextrin Inclusion Complex Crystals

“…18 γ-CD dissolved in water immediately adsorbs onto the interface to reduce the interface energy between the ChO droplets and water. 14 The ChO/γ-CD inclusion complex formed at the interface stabilizes the dispersion of the nanodroplets. Following the removal of the residual ethanol and the cooling process to 25 °C, the NS-I particles were obtained, where the ChO/γ-CD inclusion complex adsorbed at the interface of ChO in the liquid state or in a mixture of the liquid-crystalline and liquid states.…”

“…12,13 The crystals of the CD inclusion complex have also been studied as solid particles used to form Pickering emulsions. 14 Mathapa et al prepared a Pickering emulsion using n-tetradecane as the oil and α-CD and β-CD inclusion complex crystals as the solid particles at the interface. 15,16 There are an increasing number of reports on Pickering emulsions using CD inclusion complex crystals, although most of the reported emulsions are not yet nanosized but microsized.…”

“…The o/w emulsions were stabilized by the adsorption of the n -dodecane/CD inclusion complex at the liquid–liquid interface between the oil and water. We have previously reported that drug nanocrystals can be stabilized by CDs, which are adsorbed at the solid–liquid interface of drug nanocrystals and water. , The crystals of the CD inclusion complex have also been studied as solid particles used to form Pickering emulsions . Mathapa et al prepared a Pickering emulsion using n -tetradecane as the oil and α-CD and β-CD inclusion complex crystals as the solid particles at the interface. , There are an increasing number of reports on Pickering emulsions using CD inclusion complex crystals, although most of the reported emulsions are not yet nanosized but microsized …”

Microbial Cyclodextrin Glycosyltransferases: Sources, Production, and Application in Cyclodextrin Synthesis

“…Matencio et al [192] Cyclodextrin-based Pickering Emulsions: Functional Properties and Drug Delivery Focusses on methods to prepare Pickering emulsions and lipid encapsulation together with features of CD-based Pickering emulsions and Jug et al [193] Applications their applications in cosmetics, drug delivery, as antifungals, and future perspectives.…”

Green Nanoemulsion Stabilized by In Situ Self-Assembled Natural Oil/Native Cyclodextrin Complexes: An Eco-Friendly Approach for Enhancing Anticancer Activity of Costunolide against Lung Cancer Cells

“…In the research of cancer therapy, scientists have focused more on nanoemulsion due to its essential properties that achieve effective therapeutic goals through providing a large surface area, as well as increasing the drug's half-life, with selectivity in targeting [16]. Nanoemulsion as a carrier for a lipophilic compound (CTD) is a colloidal system consisting of two immiscible liquids stabilized by emulsifiers [17]. In the literature, primarily, two techniques for the formulation of nanoemulsions have been documented.…”