Protein fractionation using selective adsorption on clay surface before filtration

Citation
C. Causserand et al., Protein fractionation using selective adsorption on clay surface before filtration, J MEMBR SCI, 186(2), 2001, pp. 165-181
Citations number
19
Categorie Soggetti
Chemistry,"Chemical Engineering
Journal title
JOURNAL OF MEMBRANE SCIENCE
ISSN journal
03767388 → ACNP
Volume
186
Issue
2
Year of publication
2001
Pages
165 - 181
Database
ISI
SICI code
0376-7388(20010530)186:2<165:PFUSAO>2.0.ZU;2-F
Abstract
Protein fractionation by membrane filtration has been investigated through the selective adsorption on clay particles. The micro-filtration of bovine serum albumin, haemoglobin and montmorillonite mixtures was carried out. Bo th proteins have similar molecular weights, bovine serum albumin (BSA) has an isoelectric point at pH 4.8 while haemoglobin (Hb) is positively charged up to pH 7.0. The aim was to improve the selectivity of the separation by exploiting the different electrostatic interactions and in the meantime to reduce membrane fouling by proteins, thanks to the formation of a secondary membrane by the clay particles on top of the original membrane. We have st udied the effects of suspension characteristics (pH, ionic strength, protei n and clay concentrations) on adsorption isotherms of protein on clay parti cles and on separation performances such as micro-filtration limiting flux, protein transmission and separation factor. The optimum results were obtai ned with an ionic strength of 10(-3) M and a pH value around 7.0. In these conditions, only Hb was adsorbed on clay particles while BSA stayed free in solution. (C) 2001 Elsevier Science B.V. All rights reserved.