Enhanced protein affinity and selectivity of clustered-charge anion-exchange adsorbents.
In this work, we examined the possibility of improving ion-exchange adsorbent performance by nanoscale structuring of ligands into clusters of fixed size rather than a random distribution of individual charges. The calcium-depleted form of the protein alpha-lactalbumin, which displays a cluster of acidic amino acid residues, showed enhanced adsorption affinity and capacity on clustered-charge pentalysinamide and pentaargininamide adsorbents as compared to single-charge lysinamide and argininamide adsorbents of matched total charge. Two differently charge-clustered mutants of rat microsomal cytochrome b(5), E11Q and E44Q, with the same total charge also were well differentiated by clustered-charge adsorbents. Thus, an organized rather than random distribution of charges may produce adsorbents with higher capacity and selectivity, especially for biomolecules with inherent charge clustering.
Fu
Joseph Y
JY
Biomedical Engineering Program, Department of Biology and Biochemistry, University of Houston, 4800 Calhoun, Houston, Texas 77204-4004, USA.
Balan
Sindhu
S
Potty
Ajish
A
Nguyen
Van
V
Willson
Richard C
RC
D000327:Adsorption; D000837:Anion Exchange Resins / Q000737:chemistry*; D011506:Proteins / Q000737:chemistry*; D013816:Thermodynamics
D000837:Anion Exchange Resins; D011506:Proteins