Novel “acid tuned” deep eutectic solvents based on protonated L-proline

The paper presents new types of deep eutectic solvents (DESs) based on L-proline protonated using three different acids (hydrochloric, sulfuric and phosphoric)and playing the role a hydrogen bond acceptor(HBA). Glucose xylitol were used as donors (HBD). A series with various mole ratios obtained for systems L-proline: glucose xylitol. Density, melting point, pH viscosity synthesized DESs determined along effect water content, fraction HBA in DES temperature properties DESs. wide range densities (1343–1606 kg/m3), viscosities at 20 °C (699.6–48,590 mPa·s) 0.1 M solutions (1.578–2.456) make potentially applicable numerous technological processes, extractions well analytical techniques, including microextraction. Components these are natural origin non-toxic, thus environmentally friendly suitable food pharmaceutical industry.