Nanosystems Consisting of Iron Oxide and Serum Albumin As a Platform for Drug Delivery into Cells: Analysis of the Cy5-HSA@IONPs Nanosystem Components before and after Accumulation by Tumor Cells

The hybrid shell@core nanosystem Cy5-HSA@IONPs containing magnetic iron oxide core and Cy5-HSA shell was engineered and characterized by composition, stability and integrity using fluorescent measurements, UV/Vis-spectrophotometry (particularly, Bradford protein assay), dynamic light scattering, electron magnetic resonance in solution, in cells and cell lysates. Conjugation of HSA to Cyanine 5 (Cy5) fluorescent dye was carried out for qualitative and quantitative estimations. The research included incubation of hybrid nanosystems with human adenocarcinoma cells (HCT116 and MCF7, colon and breast cell lines, respectively) followed by cell lysis, magnetic separation and quantitative determination of protein on the surface of the magnetic cores after mild cell lysis and in suspension of cell residues. The presence of the albumin coating on the surface of magnetic cores (IONPs) upon delivery to the cells has been proven and the effectiveness of the engineered hybrid particles as a drug (photosensitizer) delivery platform has been discussed.