Separation of curcuminoids using ionic liquid based aqueous two-phase system coupled with in situ dispersive...

Area of Science:

• Analytical Chemistry
• Separation Science
• Green Chemistry

Background:

• Curcuminoids are valuable compounds with therapeutic potential.
• Efficient and selective extraction methods are crucial for their isolation.
• Existing methods may lack efficiency or involve harsh chemicals.

Purpose of the Study:

• To develop a novel extraction system for curcuminoids.
• To combine aqueous two-phase extraction (ATPS) with dispersive liquid-liquid microextraction (DLLME).
• To utilize imidazolium ionic liquids (ILs) for enhanced separation efficiency.

Main Methods:

• An IL-based ATPS was established using 1,3-diethylimidazolium iodine (EeimI) and potassium hydrogen phosphate.
• A metathesis reaction with lithium bis[(trifluoromethyl)sulfonyl]imide (LiNTf2) formed a water-immiscible IL (EeimNTf2).
• In situ DLLME and back extraction with NaOH were employed for purification and precipitation.

Main Results:

• The ATPS-DLLME method demonstrated efficient separation of curcuminoids.
• A recovery rate of 93% was achieved at pH 3.0.
• Application to Curcuma Longa yielded 0.96±0.02% extraction yield with >51% purity.

Conclusions:

• The developed ATPS-DLLME method offers a highly efficient and selective approach for curcuminoid separation.
• The dual use of the imidazolium cation in the process enhances its sustainability.
• This method shows promise for the industrial-scale extraction of curcuminoids from natural sources.