Cytotoxicity profiling of deep eutectic solvents to human skin cells

Abstract

The tailor-made character of deep eutectic solvents (DES) turns them very attractive to be used in several applications, including in health-related areas such as pharmaceutical, nutraceutical, and cosmetic industries. However, although DES has been touted as “green” solvents, several works proved that their potential toxicity should not be neglected. Using the premise of DES applicability in the cosmetic and pharmaceutical sectors, we chose two cell lines to work as a skin model (keratinocytes HaCaT and tumor melanocytes MNT-1), to assess DES cytotoxicity. The effect of three different hydrogen bond acceptors (HBA) ([Chol]Cl, [N 1111 ]Cl and [N 4444 ]Cl) and three different hydrogen bond donors (HBD) (hexanoic and butanoic acid, ethylene glycol, 1-propanol and urea) were evaluated through a common viability assay (MTT assay). Results were promising since [Chol]Cl and [N 1111 ]Cl- based DES showed good biocompatibility for the tested cells. [N 4444 ]Cl-based DES, however, showed cytotoxicity for both cell lines, with the HBA being the driver of the toxicity. Interestingly, some compounds increased cell viability in the HaCaT cell line, namely [Chol]Cl, ethylene glycol, hexanoic acid, urea, and all [Chol]Cl and [N 1111 ]Cl-based DES and should be considered as targets for future studies. These results highlight their possible use in cosmetic or pharmaceutical formulations.

Deep Eutectic Solvents as Extraction Media for Valuable Flavonoids from Natural Sources

“…In the work of Macario et al [30], a series of DES comprised of ChCl, tetramethylammonium chloride ([N1111]Cl), and tetrabutylammonium chloride ([N4444]Cl) as HBAs, in combination various HBDs, were extensively studied for their cytotoxicity against two human skin cell lines, HaCaT32-35 (chosen as model for cosmetic applications) and MNT-136-38 (selected as a model to understand the potential of the DES under study for the treatment of skin disorders). The ChCl-and [N1111]Cl-containing DES were not cytotoxic, and some of them even increased cell viability.…”

Simultaneous Separation of Antioxidants and Carbohydrates From Food Wastes Using Aqueous Biphasic Systems Formed by Cholinium-Derived Ionic Liquids

“…The MTT assay is based on the ability of viable cells to convert MTT into formazan, a water insoluble compound that can be colorimetrically quantified. It is a widely used assay to evaluate cytotoxicity being suitable for high throughput screening (HTS) (Riss et al, 2016; Sharma et al, 2018; Macário et al, 2019; Thamke et al, 2019). Furthermore, the available published studies performed with the same cell line (Caco-2 cell line) and the same incubation period (24 h) used MTT (García-Lorenzo et al, 2008; Egorova et al, 2015a,b); therefore, this assay also allows to perform comparisons with other fluorinated ILs used in the creation of ABS with carbohydrates.…”

Effect of Hydrogen Bond Donors and Acceptors on CO2 Absorption by Deep Eutectic Solvents

“…In recent years, the unprecedented amount of carbon dioxide (CO 2 ) emissions, resulting mainly from fossil fuel utilization/based activities, have impacted global warming [1,2] and climate change [3][4][5]. Conventional amine-based CO 2 mitigation techniques have been considered as effective CO 2 capture methods over the past several decades, despite some serious drawbacks, such as solvent loss, corrosion, degradation and, more importantly, high regeneration energy cost [6][7][8][9][10][11][12].…”