abstract
Immunoglobulin G (IgG) has been used in the treatment of cancer, autoimmune diseases and neurological disorders, however, the current technologies to purify and recover IgG from biological media are of high-cost and time-consuming, resulting in high-cost products. In this sense, the search for cost-effective technologies to obtain highly pure and active lgG is highly required. The present work proposes a simple and efficient method for the purification and recovery of IgG from rabbit serum using magnetic iron oxide nanopartides (magnetite, Fe3O4) coated with hybrid shells of a siliceous material modified with the anionic polysaccharide It-carrageenan. Experimental parameters such as pH, contact time between the hybrid magnetic nanoparticles (HMNPs) and rabbit serum, and total protein concentration or dilution factor of serum were evaluated. The best results were achieved at pH 5.0, with a contact time of 60 min and using a rabbit serum with a total protein concentration of 4.8 mg.mL(-1). Under these conditions, it was obtained an IgG purification factor and adsorption yield onto the HMNPs of 3.0 and 90%, respectively. The desorption of IgG from the HMNPs was evaluated using two strategies: a KCI aqueous solution and buffered aqueous solutions. Comparing to the initial rabbit serum, an IgG purification factor of 2.7 with a recovery yield of 74% were obtained using a buffered aqueous solution at pH 7.0. Alter desorption, the secondary structure of lgG and other proteins was evaluated by circular dichroism and no changes in the secondary structure were observed, meaning that the lgG integrity is kept after the adsorption and desorption steps. In summary, the application of HMNPs in the purification of IgG from serum samples has a high potential as a new downstream platform. (C) 2020 Elsevier B.V. All rights reserved.
keywords
IONIC LIQUIDS; PURIFICATION; PROTEIN; EXTRACTION; PARTICLES; SYSTEMS; BEADS
subject category
Biochemistry & Molecular Biology; Chemistry; Polymer Science
authors
Magalhaes, FF; Almeida, MR; Soares, SF; Trindade, T; Freire, MG; Daniel-da-Silva, AL; Tavares, APM
our authors
Projects
Projeto de Investigação Exploratória: Ana Paula Tavares (IF Ana Paula Tavares)
Projeto de Investigação Exploratória: Ana Luísa Silva (IF/00405/2014)
acknowledgements
This work was developed within the scope of the project CICECO-Aveiro Institute of Materials, UIDB/50011/2020 & UIDP/50011/2020, financed by national funds through the FCT/MEC and when appropriate co-financed by FEDER under the PT2020 Partnership Agreement and, and within the project POCI-01-0145-FEDER-031268 - funded by FEDER, through COMPETE2020 -Programa Operacional Competitividade e Internacionalizacao (POCI), and by national funds (OE), through FCT/MCTES. A. P. M. Tavares acknowledges FCT for the research contract under the FCT Investigator Programme and Exploratory Project (IF/01634/2015). A. L. Daniel-da-Silva acknowledges FCT for the research contract under the Program 'Investigador FCT' (IF/00405/2014). S. F. Soares thanks FCT for the Ph.D. grant SFRH/BD/121366/2016.