Preparation and Characterization of Aminosilane-Functionalized Magnetic Antibody Conjugates for Bacterial Recognition and Capture

In this paper, we present the synthesis and characterization of antibody-conjugated aminosilane-functionalized iron oxide nanoparticles (Se-IgG-Ab-[Fe₃O₄@APTES]). Iron oxide nanoparticles are synthesized through a co-precipitation method followed by the surface modification with (3-aminopropyl)triethoxysilane (APTES) and subsequently by the bioconjugation of a specific antibody. The prepared antibody-conjugated magnetic nanomaterials were characterized by X-ray diffraction, transmission electron microscopy, Fourier transform infrared spectra, and vibrating sample magnetometry. The Se-IgG-Ab-[Fe₃O₄@APTES] conjugates exhibited a capability to detect and capture Gram-negative bacteria, Salmonella enteritidis, at low concentration. These results suggest that the specific antibody-conjugated magnetic nanomaterials can be used as a promising platform for efficient bacterial capture and separation applications.