Fabrication of Superparamagnetic Iron Oxide Nanoparticles for Magnetic Cell Targeting Purposes

Magnetic cell targeting is a novel non-invasive cellular delivery technique. It improves stem cell delivery to and retention in the injury site. Labeling cells with superparamagnetic iron oxide nanoparticle (SPION) is one of the most important steps of this technique. Appropriate SPIONs selection is believed to be of vital importance.

The current study aimed to produce SPIONs which are capable of attaching to Mesenchymal stem cells surface (MSCs).

Dextran coated SPIONs were produced following co-precipitation method under N2 atmosphere. Bone marrow derived MSCs were isolated and cultured from rabbit humerus bone. Anti-rabbit CD44 monoclonal antibody was attached to the surface of SPIONs and MSCs and were labeled with this final product. SPIONs coating process, particle size, and antibody conjugation efficacy were evaluated using FT-IR, SEM, and Bradford protein measurement assay, respectively. Attachment of antibody-linked dextran coated SPIONs to MSCs was accessed utilizing Prussian blue staining, immunofluorescence analysis, and SEM analysis.

Peaks of FT-IR at 3200 cm-1 and 2922 cm-1 are representative of dextran. The average particle size was 56.13±6.67. The average antibody-SPION conjugation ratio was 77.78±6.35%. The average percentage of the labeled cells in Prussian blue and IF analysis were 71.57±2.53 and 95.04±0.95, respectively. MSCs-SPIONs conjugation was also confirmed via SEM analysis.

In conclusion, it could be inferred that mesenchymal stem cells could successfully be labeled with dextran coated-anti CD44 antibody conjugated- superparamagnetic Iron oxide nanoparticles. This product could be used for further in-vitro and in-vivo evaluations.