Effects Of Polymer Ph And Molar Mass On The Peg/phosphate Aqueous Two-phase System [efeitos Do Ph E Massa Molar Do Polímero Sobre O Sistema Bifásico Aquoso Peg/fosfato]

Liquid-liquid extraction using aqueous two-phase systems (ATPSs) is a promising technique for the purification of biomolecules of industrial and laboratory interest. This work presents a study of the phase diagrams for different poly(ethylene glycol) (PEG) molar masses (ranging from 400 to 4000) and potassium phosphate at pH varying from 6 to 11 in standard conditions. The influence of PEG molecular mass at different pHs was studied from the phase diagrams formed. Stock solutions of PEG 400 and 4000 (100 and 50% w w -1, respectively) and phosphate (20% w w -11 KH 2PO 4/K 2HPO 4) were prepared at the appropriate pH (6, 7, 8 and 9). For pHs 10 and 11, NaOH 1M was used in addition to the salts. The results showed that low concentrations were used to form the ATPS with high molecular mass PEG. On the other hand, there was no pH influence in the equilibrium curves -in other words, a significant shift of the binodal in different pHs.33114Albertsson, P.A., (1971) Partition of Cell Particles and Macromolecule, , New York: John Wiley and SonsBadr, M.K., Cabezas, H., A thermodynamic model for the phase behavior of salt-polymer aqueous two-phase system (1996) Fluid Phase Equilibria, 155 (17), pp. 39-58Cabezas, H., Theory of phase formation in aqueous two-phases systems (1996) Journal of Chromatography B: Biomedical Applications, 680 (17), pp. 3-30Diamond, A.D., Hsu, J.T., Aqueous two phase systems for biomolecule separation (1992) Advances in Biochemistry Engineering, 47 (135), pp. 89-135Franco, T.T., (1992) Use of Modified Proteins in Aqueous Two-phase Systems. Effect of Surface Hydrophobicity and Charge, pp. 184f. , Thesis (Doctoral in Biochemical Engineering)-Departament of Agriculture and Food, University of Reading, Reading 1992Ferreira, G.B., Evangelista, A.F., Junio, J.B.S., Rodrigues De Souza, R., Santana, J.C.C., Tambourgi, E.B., Jordao, E., Partitioning optimization of proteins from Zea mays malt in ATPS PEG 6000/CaCl2 (2007) Brazilian Archives of Biology and Technology, 50 (3), pp. 557-564Harris, J.M., (1992) Poly (Ethylene Glycol) Chemistry: Biochemical and Biomedical Applications, , New York: Plenum PressKroner, K.H., Stach, W., Schutte, H., Kula, M.R., Scale-up of formate dehydrogenase isolation by partition (1982) Journal of Chemistry Technology and Biotechnology, 32 (1), pp. 130-137Pessoa Júnior, A., Kilikian, B.V., (2005) Purificação de Produtos Biotecnológicos, , Barueri: ManoleVideira, M., Aires-Barros, M.R., Liquid-liquid extraction of clavulanic acid using an aqueous two-phase system of polyethylene glycol and potassium phosphate (1994) Journal of Chromatography A, 668 (1), pp. 237-240. , DOI 10.1016/0021-9673(94)80113-4Zuniga, A.D.G., Coimbra, J.S.R., Minim, L.A., Meirelles, A.J.A., Extração líquido-líquido usando sistemas aquosos bifásicos: uma revisão (2003) Boletim da Sociedade Brasileira de Ciência e Tecnologia de Alimentos, 37 (2), pp. 89-10