Potential of aqueous two-phase systems for the separation of levodopa from similar biomolecules

authors	Sousa, RDS; Neves, CMSS; Pereira, MM; Freire, MG; Coutinho, JAP
nationality	International
journal	JOURNAL OF CHEMICAL TECHNOLOGY AND BIOTECHNOLOGY
author keywords	aqueous two-phase systems; levodopa; amino acids; extraction; separation; ionic liquids
keywords	IONIC LIQUIDS; BIPHASIC SYSTEMS; MUCUNA-PRURIENS; EXTRACTION; QUANTIFICATION; ADJUVANTS; DISEASE; SEEDS; WATER; RAT
abstract	BACKGROUNDLevodopa is a precursor of several neurotransmitters, such as dopamine, and is used in the treatment of Parkinson's disease. In this work, an alternative strategy was studied to separate levodopa from similar biomolecules using aqueous two-phase systems (ATPS). RESULTSTernary ATPS composed of polyethylene glycol (PEG) 400 or ionic liquids (ILs), citrate buffer (K3C6H5O7/C6H8O7) at pH 7.0 and water, and quaternary ATPS composed of PEG 400, K3C6H5O7/C6H8O7 at pH 7.0, water and the same ILs at 5 wt%, were studied. The respective liquid-liquid phase diagrams were determined at 298 K to appraise the mixture compositions required to form two-phase systems, followed by studies of the partition of levodopa and structurally similar biomolecules (dopamine, L-phenylalanine, and L-tyrosine). Their partition coefficients and extraction efficiencies have been determined, and the selectivity of the ATPS to separate levodopa from the remaining biomolecules evaluated. CONCLUSIONThe results obtained indicated that PEG-based ATPS were the most effective to separate levodopa from L-phenylalanine while the separation from the other biomolecules was better using IL-based ATPS, in particular those based on [P-4444]Cl and [N-4444]Cl, with extraction efficiencies of levodopa to the salt-rich phase ranging between 62.7 and 74.0%, and of the remaining biomolecules to polymer/IL-rich phase up to 91.5%. (c) 2017 Society of Chemical Industry
publisher	WILEY
issn	0268-2575
year published	2018
volume	93
issue	7
beginning page	1940
ending page	1947
digital object identifier (doi)	10.1002/jctb.5553
web of science category	Biotechnology & Applied Microbiology; Chemistry, Multidisciplinary; Engineering, Environmental; Engineering, Chemical
subject category	Biotechnology & Applied Microbiology; Chemistry; Engineering
unique article identifier	WOS:000435087800014