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.