Immobilization of Concanavalin A on iron oxide magnetic nanoparticles. Effect of Bovine Serum Albumin in the recognition interactions of the lectin

SOLANGE M. SELZER, RAQUEL I VICO, NANCY FERREYRA

Surfaces and Interfaces

Elsevier

Año: 2022 vol. 30 p. 101908 - 101919

2468-0230

Iron oxide magnetic nanoparticles are engaging platforms for diverse nanobiotechnological applications, such asproteins separation and glico-biosensing mediated by the surface functionalization with lectins as recognitionelements. We present a new strategy for the union of the lectin Concanavalin A (ConA) at the surface ofcarboxylated iron oxide magnetic nanoparticles (IOMNPs-Ar-COOH). The nanoparticles were obtained by asingle step synthesis in the presence of the aryl diazonium salt derived from 4-aminobenzoic acid. The sponta-neous grafting allowed to obtain carboxylic acid covalently functionalized magnetite nanoparticles with thecarboxylate group exposed to the solution, as was evidenced through the exhaustive characterization by XRD,FTIR, Raman spectroscopy, and TEM analysis. The nanoparticles of Fe3O4 of (6.6 ± 0.7) nm diameter exhibitedgood magnetic field responsiveness towards an external magnet and stability towards the environmentaloxidation. The carboxylic acid groups exposed were used for the conjugation with ConA and participated in itsadsorption onto the surface. The ability of ConA to recognize the glycoprotein Glucose Oxidase (GOx) wasanalyzed in real time by surface plasmon resonance. These results were correlated with the responses obtained byelectrochemical methods (electrochemical impedance spectroscopy, and cyclic voltammetry). Considering thepossible applications of this nanomaterial, we also evaluate the effect of Bovine Serum Albumin (BSA) in therecognition capability of ConA. Our work let us to conclude that although ConA does not specifically recognizeBSA, this protein alters the affinity of ConA for GOx giving an interesting vision of the behaviour of this hybridnanomaterial in physiological mediums or other matrixes with high concentration of proteins where thisnanomaterial could be employed e.g., in a biosensor or the separation of a glycoprotein, among others