Batalha, IL, Hussain A, Roque ACA.
2010.
Gum Arabic coated magnetic nanoparticles with affinity ligands specific for antibodies, oct. Journal of Molecular Recognition. 23:462–471., Number 5
AbstractA novel magnetic support based on gum Arabic {(GA)} coated iron oxide magnetic nanoparticles {(MNP)} has been endowed with affinity properties towards immunoglobulin G {(IgG)} molecules. The success of the in situ triazine ligand synthesis was confirmed by fluorescence assays. Two synthetic ligands previously developed for binding to {IgG}, named as ligand 22/8 (artificial Protein A) and ligand 8/7 (artificial Protein L) were immobilized on to {MNPs} coated with {GA} {(MNP\_GA).} The dimension of the particles core was not affected by the surface functionalization with {GA} and triazine ligands. The hydrodynamic diameters of the magnetic supports indicate that the coupling of {GA} leads to the formation of larger agglomerates of particles with about 1 microm, but the introduction of the triazine ligands leads to a decrease on {MNPs} size. The non-functionalized {MNP\_GA} bound 28 mg {IgG/g}, two times less than bare {MNP} (60 mg {IgG/g).} {MNP\_GA} modified with ligand 22/8 bound 133 mg {IgG/g} support, twice higher than the value obtained for ligand 8/7 magnetic adsorbents (65 mg/g). Supports modified with ligand 22/8 were selected to study the adsorption and the elution of {IgG.} The adsorption of human {IgG} on this support followed a Langmuir behavior with a Q(máx) of 344 mg {IgG/g} support and K(a) of 1.5 x 10(5) M. The studies on different elution conditions indicated that although the 0.05 M citrate buffer {(pH} 3) presented good recovery yields (elution 64% of bound protein), there was occurrence of iron leaching at this acidic {pH.} Therefore, a potential alternative would be to elute bound protein with a 0.05 M {glycine-NaOH} {(pH} 11) buffer.