Toward a deeper and simpler understanding of serum protein-mediated transformations of magnetic nanoparticles by ICP-MS.

A great variety of magnetic nanomaterials are entering preclinical investigations with the objective to select the most promising candidates for diagnostic and therapeutic applications. For an analytical approach to be used as a high-throughput screening tool, simple and cost-efficient sample preparation protocol is a basiс prerequisite. Here, we demonstrate how the application of continuous magnetic field allows for quantitatively separating iron oxide magnetic nanoparticles from a mixture with human serum to facilitate monitoring of their biomolecular interactions with high-resolution inductively coupled plasma mass spectrometry. By measuring the signals of sulfur and metal isotopes, it is possible to monitor the formation of the protein corona and alterations in the concentrations of relevant metals due to binding of specific metalloproteins, respectively.