Please use this identifier to cite or link to this item: http://repositorio.unicamp.br/jspui/handle/REPOSIP/60366
Type: Artigo de periódico
Title: Interaction of histidine-tagged human proinsulin with immobilized nickel ion: Effect of chelating ligand and thermodynamics analysis
Author: de Goes, LC
Miranda, EA
Bueno, SMA
Abstract: The nature of the chelating ligand is one of various factors affecting the performance of IMAC. In this work we studied the effect of three chelating ligands on the adsorption of recombinant human proinsulin with His-tag (proinsulin-(His)(6)). The chelating ligands (complexed with Ni(II)) were two tetradentates (carboxymethylated aspartic acid, CM-Asp, and tris(2-aminoethyl)amine, TREN) and one pentadentate (tris (carboxymethyl) ethylenediamine, TED). Their performance were compared with the performance of one tridentate ligand (iminodiacetic acid, IDA) and the commercial adsorbent HisTrap both also complexed with Ni(11). Higher selectivities were achieved with Ni(II)-CM-Asp and Ni(II)-TED. The adsorption capacity decreased according to the order: TREN, HisTrap, IDA, CM-Asp, and TED (172.82, 167.98, 133.09, 110.18, and 69.22 mg of proinsulin/mL of gel, respectively, at 25 degrees C). Although TREN-agarose had the highest capacity, the ligand with the second highest capacity - HisTrap - showed better performance since proinsulin was eluted in a single, concentrated peak with imidazole, while for Ni(II)-TREN proinsulin was eluted with imidazole and EDTA, requiring an extra step to free the product from the EDTA. Therefore, the choice of an adsorbent for this separation depends on the priority: capacity (TREN or HisTrap for one step process) or selectivity (CM-Asp). Adsorption isotherms were determined for temperatures from 4 to 45 degrees C and the Langmuir model was fitted to the experimental data. The thermodynamics analysis showed positive Delta H(o) (from 18.83 to 86.05 kJ/mol), indicating that the adsorption of proinsuin-(His)(6) in all chelating ligands is an endothermic process. The negative change in Gibbs free energy (from -26.30 to -35.11 kJ/mol) indicated that the adsorption of the proinsulin-(His)(6) on all the adsorbents studied was a thermodynamically favorable process. (C) 2010 Elsevier B.V. All rights reserved.
Subject: IMAC
Isotherms
Recombinant proinsulin
Adsorption
Thermodynamic parameters
Country: Holanda
Editor: Elsevier Science Bv
Rights: fechado
Identifier DOI: 10.1016/j.colsurfa.2010.08.019
Date Issue: 2010
Appears in Collections:Unicamp - Artigos e Outros Documentos

Files in This Item:
File Description SizeFormat 
WOS000283395600025.pdf864.38 kBAdobe PDFView/Open


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.