Citronellol-based hydrophobic NADES: physicochemical characterization and analytical applications focused on NSAIDs extractions

Abstract

The widespread presence of non-steroidal anti-inflammatory drugs (NSAIDs) in aquatic environments has raised concerns due to their persistence and ecological impact. Natural Deep Eutectic Solvents (NADES) have emerged as promising green alternatives for the extraction of organic pollutants.Four novel NADES were prepared combining citronellol with menthol, camphor, capric acid and borneol. Their properties were studied through measurements of viscosity, density, pH, conductivity, spectroscopic properties (UV–Vis absorption, fluorescence, FT-IR) and differential scanning calorimetry. These characteriza­tions provided insight into the structural and thermal behavior of the solvents, key to understanding their extraction performance and analytical potential.The results demonstrated that specific eutectic mixtures, particularly those with low viscosity and suitable acidity, achieved high extraction efficiencies (above 90 %). Additionally, some NADES exhibited intrinsic fluorescence signals, with a linear response in the presence of NSAIDs, suggesting their potential utility as green solvents in analytical methods. Moreover, citronellol-based NADES show promise as environmentally friendly solvents for the removal of pharmaceutical contaminants from water.