89Zr-Labeled DFO@Durvalumab-HSA nanoparticles: In vitro potential for triple-negative breast cancer

This study presents the development and evaluation of a DFO@mAb-NP (DFO@Durvalumab-HSA-DTX nanoparticle) nanoplatform for imaging in triple-negative breast cancer (TNBC). The nanoplatform demonstrated significant changes postconjugation with DFO, evidenced by increased particle size from 178.1 ± 5 nm to 311 ± 26 nm and zeta potential alteration from −31.9 ± 3 mV to −40.5 ± 0.8 mV. Fourier-transform infrared spectroscopy and ultraviolet spectral analyses confirmed successful DFO conjugation, with notable shifts in peak wavelengths. High labeling efficiency was achieved with ⁸⁹Zr, as indicated by thin layer radio chromatography and high-performance liquid radio chromatography results, with labeling efficiencies of 98 ± 2% for ⁸⁹Zr-DFO@mAb and 96 ± 3% for ⁸⁹Zr-DFO@mAb-NP. The nanoplatforms maintained stability over 24 h, showing less than 5% degradation. Lipophilicity assays revealed logP values of 0.5 ± 0.03 for ⁸⁹Zr-DFO@mAb-NP and 0.98 ± 0.2 for ⁸⁹Zr-DFO@mAb, indicating a higher lipophilic tendency in the radiolabeled Durvalumab. Cell uptake experiments showed an initial high uptake in MDA-MB-468 cells (45.1 ± 3.2%), which decreased over time, highlighting receptor-specific interactions. These comprehensive findings suggest the promising potential of the DFO@mAb-NP nanoplatform for targeted imaging in TNBC, with implications for improved diagnostic accuracy and treatment strategies.