resumo
Aqueous micellar two-phase systems (AMTPS) using surfactants have been widely applied as an advantageous extraction technology for a wide range of (bio)molecules. When composed by two surfactants (the second one used as the co-surfactant), the extractive performance of such systems is considerably boosted. In this context, this work looks at ionic liquids (ILs) as a new class of tunable co-surfactants to be applied in AMTPS. Three distinct families of ILs, namely imidazolium, phosphonium and quaternary ammonium were applied in the design of the binodal curves of novel AMTPS based on the nonionic surfactant Triton X-114. On these systems it was investigated the impact of the IL absence/presence, concentration and structural features on the binodal curves behavior. Aiming at evaluating their applicability as extraction systems, partitioning studies of two targeted (bio)molecules, namely the protein Cytochrome c (Cyt c) and the dye/model drug Rhodamine 6G (R6G), were carried out. It is shown that the presence of ILs as co-surfactants is able not only to enhance the partition coefficients of Cyt c (indicated as logK(cyt) (c)) from -0.59 +/- 0.12 up to -1.51 +/- 0.14, but also to improve the selectivity parameter (S-R6G/cyt (c)) from 925.25 up to 3418.89. The results here obtained open new perspectives in the design of liquid-liquid separation processes, transversal to various fields and a wide range of applications. (C) 2014 Elsevier B.V. All rights reserved.
palavras-chave
CLOUD-POINT EXTRACTION; NONIONIC SURFACTANTS; AGGREGATION BEHAVIOR; CATIONIC SURFACTANTS; PHASE-SEPARATION; PURIFICATION; PROTEINS; ELECTROLYTES; FLUORESCENCE; BIOMOLECULES
categoria
Engineering
autores
Vicente, FA; Malpiedi, LP; Silva, FAE; Pessoa, A; Coutinho, JAP; Ventura, SPM
nossos autores
Ana Francisca Osório de Almeida Coelho e Silva
Investigador Júnior
Filipa Alexandra André Vicente
Estudante de doutoramento
Sónia Patrícia Marques Ventura
Professor AuxiliarGrupos
G4 - Materiais Renováveis e Economia Circular
G5 - Materiais Biomiméticos, Biológicos e Vivos
agradecimentos
This work was also financed by FEDER through Programa Operacional Fatores de Competitividade - COMPETE and national funds through FCT - Fundacao para a Ciencia e Tecnologia within CICECO project - FCOMP-01-0124-FEDER-037271 (Ref. FCT PEst-C/CTM/LA0011/2013). The authors also acknowledge FCT by the doctoral and post-doctoral grants SFRH/BD/94901/2013 and SFRH/BPD/79263/2011 of F.A. e Silva and S.P.M. Ventura, respectively. The authors also thank the Santander Scholarship granted to F.A. Vicente. The authors acknowledge the financial support from FAPESP through the project FAPESP 2012/12022-6 and FAPESP, Process No 2011/20521-0 to L.P. Malpiedi. This project was also supported by Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES) and Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq) from Brazil.