title: Improving the extraction and purification of immunoglobulin G by the use of ionic liquids as adjuvants in aqueous biphasic systems.
abstract: Immunoglobulins G (IgG) could become widespread biopharmaceuticals if cost-efficient processes for their extraction and purification are available. In this work, aqueous biphasic systems (ABS) composed of polyethylene glycols and a buffered salt, and with ionic liquids (ILs) as adjuvants, have been studied as alternative extraction and purification platforms of IgG from a rabbit serum source. Eleven ILs were investigated to provide insights on the chemical features which maximize the IgG partitioning. It is shown that in polymer-salt systems pure IgG preferentially partitions to the polymer-rich phase; yet, the complete extraction was never attained. Remarkably, after the addition of 5wt% of adequate ILs to polymer-salt ABS, the complete extraction of pure IgG in a single-step was accomplished. The best systems and conditions were then applied to the extraction and purification of IgG directly from rabbit serum samples. The complete extraction of IgG in a single-step was maintained while its purity in the polymer-rich phase was enhanced by ca. 37% as compared to the IL-free ABS. The antibody stability was also evaluated revealing that appropriate ILs are able to maintain the IgG stability and can be used as phase-forming components of ABS when envisaging the purification of high-cost biopharmaceuticals.
authors: CICECO - Aveiro Institute of Materials, Department of Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal.
authors: Ana M
authors: AM
authors: Ferreira
authors: CICECO - Aveiro Institute of Materials, Department of Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal.
authors: Vânia F M
authors: VFM
authors: Faustino
authors: CICECO - Aveiro Institute of Materials, Department of Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal.
authors: Dibyendu
authors: D
authors: Mondal
authors: CICECO - Aveiro Institute of Materials, Department of Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal.
authors: João A P
authors: JAP
authors: Coutinho
authors: CICECO - Aveiro Institute of Materials, Department of Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal.
authors: Mara G
authors: MG
authors: Freire
mesh_terms: D000818:Animals; D006863:Hydrogen-Ion Concentration; D007093:Imidazoles / Q000737:chemistry; D007074:Immunoglobulin G / Q000097:blood / Q000737:chemistry / Q000302:isolation & purification*; D052578:Ionic Liquids / Q000737:chemistry*; D059625:Liquid-Liquid Extraction / Q000379:methods*; D011092:Polyethylene Glycols / Q000737:chemistry*; D055550:Protein Stability; D011817:Rabbits
chemical_list: D007093:Imidazoles; D007074:Immunoglobulin G; D052578:Ionic Liquids; D011092:Polyethylene Glycols
keywords: Adjuvants; Antibody; Aqueous biphasic system; Extraction; Ionic liquids; Purification