Encapsulation in cyclodextrins (CDs) and solvation in deep eutectic solvents (DESs) are both efficient strategies for the solubilization of poorly water-soluble molecules. Recently, we proposed new systems combining DESs and macrocycles using two different approaches: i) solubilizing hosts in preformed DES or ii) using hosts as a DES component leading to low melting mixtures (LMMs). This strategy could evolve in new outcomes in DES properties, more precisely provide the solvents with supramolecular capacity, and translate into interesting performances.
In this study, we prepared a LLM based on sulfobutylether-β-cyclodextrin (Captisol®) and levulinic acid (1:44 molar ratio) liquid at room temperature. We demonstrated the efficiency of this LMM for the solubilization of four steroids (beclomethasone dipropionate, budesonide, fluticasone propionate and mometasone furoate) chosen as models of poorly soluble drugs. Results show a 4000-fold increase of the solubility of fluticasone propionate using the low-melting, cyclodextrin-based, mixture versus water. This huge solubility enhancement could be linked to the formation of an inclusion complex with the cyclodextrin within the low melting mixture. Increasing drugs solubility and bio-availability could prevent their precipitation and coagulation, which is a prime feature to accomplish desired pharmacological responses, like doses reduction and consequently lower environmental impacts.
Justine Petitprez, François-Xavier Legrand, Catherine Tams, J. D. Pipkin, Vince Antle, Miriana Kfoury & Sophie Fourmentin: Huge solubility increase of poorly water‐soluble pharmaceuticals by sulfobutylether‐β‐cyclodextrin complexation in a low‐melting mixture, Environmental Chemistry Letters, 2022. https://doi.org/10.1007/s10311-022-01415-y