Deep Eutectic Solvents: A Review of Fundamentals and Applications

Abstract

Deep eutectic solvents (DESs) are an emerging class of mixtures characterized by significant depressions in melting points compared to those of the neat constituent components. These materials are promising for applications as inexpensive "designer" solvents exhibiting a host of tunable physicochemical properties. A detailed review of the current literature reveals the lack of predictive understanding of the microscopic mechanisms that govern the structure−property relationships in this class of solvents. Complex hydrogen bonding is postulated as the root cause of their melting point depressions and physicochemical properties; to understand these hydrogen bonded networks, it is imperative to study these systems as dynamic entities using both simulations and experiments. This review emphasizes recent research efforts in order to elucidate the next steps needed to develop a fundamental framework needed for a deeper understanding of DESs. It covers recent developments in DES research, frames outstanding scientific questions, and identifies promising research thrusts aligned with the advancement of the field toward predictive models and fundamental understanding of these solvents.

Selected Monocyclic Monoterpenes and Their Derivatives as Effective Anticancer Therapeutic Agents

“…This decrease is mainly attributed to hydrogen bond interactions between the different components in a DES [ 92 ]. The widespread interest in these systems is due to their many potential applications including gas separation and capture, biocatalysis and organic chemistry, power systems and battery technology, polymer fabrication, biomass processing, nanomaterial synthesis, pharmaceutical and medical research [ 15 , 16 ].…”

“…We also describe in detail various examples of therapeutic deep eutectic solvents (THEDESs) that contain a monoterpene as one of its components. To the best of our knowledge, this is the first review of natural monoterpenes and their derivatives to emphasize their eutectic equivalents for the treatment of cancer, which is surprising given how many publications explore the biological applications of deep eutectic solvents (DES) [ 15 , 16 , 17 ]. We consider THEDESs integral among terpene applications due to the proven capacity of these systems to increase the bioavailability of the active pharmaceutical ingredients (APIs).…”

The Use of Ferrofluids in Analytical Sample Preparation: A Review

“…Besides, a wide range of different natural products can be used for the synthesis of DESs. For these reasons, they have been suggested as the perfect eco-atomic economical product [49]. Furthermore, natural DESs are less toxic than conventional ILs and they present higher biodegradability [47].…”

Enabling formulations of aprepitant: in vitro and in vivo comparison of nanocrystalline, amorphous and deep eutectic solvent based formulations

“…comprising a hydrogen bond donor and acceptor. However, for a detailed a review on the complex nature of DESs, the interested reader is referred to Hansen et al (2021) , Martins et al (2019) , and Smith et al (2014) . With the increasing number of poorly soluble drug candidates, DESs possess the potential to become a part of the tool box of enabling strategies for successful formulation development of novel drugs ( Morrison et al, 2009 ; Lu et al, 2016 ; Li and Lee, 2016 ).…”