Pre-purification of genipin from genipap using aqueous-two-phase systems composed of protic ionic liquids plus polymers + water at 298 K and atmospheric pressure

The downstream processing still represents the cost bottleneck of obtaining biomolecules. Aqueous two-phase systems (ATPS) composed of alternative constituents have been presented as a cost-effective platform for the concentration, partition and/or purification of biomolecules. In this sense, this work provides a series of new ATPS composed of polymers (PPG-400, PEG-300, -400, -550 and -750 g gmol-1) + protic ionic liquids (PILs) [based on ethylene glycols (mono-, di- - and tri-ethylene glycol) as cation and inorganic anions (H2PO4- , HSO4-, Cl- , NO3- )] + water at 298 K and atmospheric pressure. An initial screening evaluated the effect of the type of polymer, molecular weight of the polymer, type of cation and anion of the ionic liquid on phases' separation, while the second series of experiments studied their application as effective platforms for the pre-purification of genipin from genipap. The results showed that the hydrophilic/hydrophobic balance between phase forming components is the driving force for the formation of ATPS, as well as for the pre-purification of genipin from genipap. The system constituted of PEG-750 (40 wt%) + [MEA][H2PO4] (30 wt%) + H2O (30 wt%) exhibited the highest genipin pre-purification performance, i.e., purification factor of 6.03, as confirmed chromatographically.

Automated summary

A series of new aqueous two-phase systems composed of polymers and protic ionic liquids were developed for the concentration, partition and/or purification of biomolecules, with a focus on pre-purifying genipin from genipap. The optimal system exhibited a purification factor of 6.03 for genipin.