Physicochemical characterization of ferric carboxymaltose and iron sucrose nanoparticles in human plasma: stability and nanoparticle-protein complex formation.

This study investigates the impact of exposure to human blood plasma on the physicochemical properties of two widely used intravenous (IV) iron-carbohydrate nanomedicines for treating iron deficiency and iron deficiency anaemia, ferric carboxymaltose and iron sucrose, with a particular focus on their colloidal stability and protein corona formation. Using dynamic light scattering (DLS), differential centrifugal sedimentation (DCS), size-exclusion chromatography (SEC), inductively coupled plasma mass spectrometry (ICP-MS), sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), and density gradient ultracentrifugation (DCS), we compared both iron-carbohydrate nanomedicines before and after plasma exposure. Both products exhibited minimal degradation and negligible protein adsorption and good colloidal stability also after exposure to blood plasma for up to 24 h. However, more pronounced changes in the surface properties of the iron sucrose NPs were observed suggesting rearrangement of the NPs' surface. These findings suggest that the high colloidal stability and low protein interaction of ferric carboxymaltose may contribute to its more sustained pharmacokinetic profile.