Gluconic acid for eco-friendly Ionic Liquids: chemical and biological investigations

Ionic liquids (ILs) are employed in several fields thanks to their well-known properties. For a long time, ILs were considered the “green” alternative to conventional organic solvents.1 However, the increasing attention on environmental health led to consider different ILs structures and alternative synthetic pathways. Considering the tunability of IL structures, new synthetic approaches with natural sources as starting materials were taken into account.2 Here, new eco-friendly ILs were synthesised using gluconic acid. The structures carry gluconic moiety on the cation or as the anion (Figure 1). Hence, several OH groups decrease toxicity and shape a high coordinative site. These new organic salts were fully characterised from a physico-chemical point of view. However, also, the study of their impact on the ecosystem health was performed. To this aim, three different cancer cell lines, Hela, HTC and MCF7 cells, were chosen to assess cytotoxicity effects of ILs.3 Moreover, haemolysis investigations were carried out to consider the effect on human blood cells. Finally, Zebrafisha organisms were used as an aquatic model for ILs toxicity.4 Indeed, the response by living organisms in an aquatic ecosystem gives additional information for dispose of ILs. In the aim of a sustainable approach, these ILs have been designed and analysed to achieve good materials with low environmental impact.