Proteomic Analysis Reveals Distinct Protein Corona Compositions of Citrate- and Riboflavin-Coated SPIONs

Abstract

Superparamagnetic iron oxide nanoparticles (SPIONs) are recognized as one of the most beneficial tools for biomedicine, especially in theranostic applications. Even though SPIONs have excellent properties regarding their biocompatibility and unique magnetic properties, they lack stability in biological fluids. To stabilize and increase the specificity of the SPIONs to target desirable cells or tissues, several surface coatings have been introduced. These surface coatings can lead to different preferences of serum protein bindings, which ultimately determine their behaviors in vitro and in vivo. Thus, understanding the interaction of SPIONs with biological systems is important for their biocompatible design and clinical applications. In this study, using proteomic analyses, we analyzed the protein corona fingerprints on SPIONs with two different coatings, including citrate and riboflavin, that have been widely used as surface coatings and ligands for enhancing cellular uptake in breast cancer cells. Though both citrate-coated SPIONs (C-SPIONs) and riboflavin-coated SPIONs (Rf-SPIONs) showed similar sizes and zeta potentials, we found that Rf-SPIONs adsorbed more serum proteins than bare SPIONs (B-SPIONs) or C-SPIONs, which was likely due to the higher hydrophobicity of the riboflavin. The enriched proteins consisted mainly of immune-responsive and blood coagulation proteins with different fingerprint profiles. Cellular uptake studies in MCF-7 breast cancer cells comparing the activities of preformed and in situ coronas showed different uptake behaviors, suggesting the role of protein corona formation in promoting the interaction between the SPIONs and the cells. The results obtained here provide the essential information for further development of the potential strategy to reduce or stimulate immune response in vivo to increase therapeutic applications of both C-SPIONs and Rf-SPIONs.

Interaction of Iron Oxide Nanoparticles with Macrophages Is Influenced Distinctly by “Self” and “Non-Self” Biological Identities

“…For instance, citrate-and riboflavin-coated IONPs appeared to showcase the divergence in the fetal bovine serum (FBS)-derived PC, as determined by a proteomic analysis, whereby riboflavin-coated IONPs associate with more Apolipoprotein E (ApoE), ApoA1, or albumin. 4 Further modifying the IONP surface can affect the biological identity of the NPs. For instance, the attachment of a low pH insertion peptide and not the cycloRGD peptide to PEGylated IONPs enhanced IONP internalization by cells in the mononuclear phagocytic system when incubated in human serum (HS)-supplemented medium.…”

“…It remains unclear whether or not the biological identity of NPs is dependent on their physicochemical properties, also known as synthetic properties. For instance, citrate- and riboflavin-coated IONPs appeared to showcase the divergence in the fetal bovine serum (FBS)-derived PC, as determined by a proteomic analysis, whereby riboflavin-coated IONPs associate with more Apolipoprotein E (ApoE), ApoA1, or albumin . Further modifying the IONP surface can affect the biological identity of the NPs.…”

Proteomic Analysis and Molecular Dynamics Simulation of Riboflavin-Coated Superparamagnetic Iron Oxide Nanoparticles Reveal Human Serum-Derived Protein Coronas: Implications as Magnetic Resonance Imaging Contrast Agents

“…As we aim to develop the Rf-SPIONs further as a theranostic platform for breast cancer, characterization of the system when exposed to biological environments is essential in predicting and understanding the behavior of the NPs beforehand. We recently analyzed the protein coronas on B-, C-, and Rf-SPIONs formed with FBS-derived proteins . Different protein-binding patterns were found among the SPIONs with different surface coatings.…”

“…B-SPIONs were synthesized by a coprecipitation method, as reported earlier. 26 Subsequent coating with tri-sodium citrate dihydrate or Rfcitrate yielded C-SPIONs and Rf-SPIONs, respectively. The synthesis setup and scheme are shown in Scheme 1A.…”

“…We recently analyzed the protein coronas on B-, C-, and Rf-SPIONs formed with FBS-derived proteins. 26 Different protein-binding patterns were found among the SPIONs with different surface coatings. In order to understand more about the interaction between the SPION surfaces and the serum proteins, interaction of the ligands with the particle surfaces must be elucidated first.…”