No abstract

moiety on AuNPs from an agonist of FRa, to anti-FRa Ig, an antibody (Ab) that binds to FRa without inducing proliferative or mitogenic effects. Materials/Methods: Pegylated 20 nm AuNPs (pAuNPs) were synthesized and conjugated to nonspecific rabbit IgG Ab (rAuNPs) or targeted anti-FRa Ab (aAuNPs). AuNPs were characterized by zeta potential, hydrodynamic diameters and absorption spectra. Uptake by MDA-MB-231 cells was analyzed qualitatively using dark field microscopy. In-vitro radiosensitization potential by aAuNPs was assessed via clonogenic assay using clinically relevant, 6MV RT. Results: Surface plasmon resonance peaks of pAuNPs, rAuNPs, and aAuNPs were observed at 521AE2 nm. AuNP zeta potentials were:-34AE6 mV (bare AuNPs),-8AE4 mV (pAuNPs),-1AE6 mV (rAuNPs), and-5AE5 mV (aAuNPs). Hydrodynamic diameters determined by dynamic light scattering were: 33AE12 nm (bare AuNPs), 56AE18 nm (pAuNPs), 64AE22 nm (rAuNPs), and 62AE17 nm (aAuNPs). aAuNPs demonstrated significant radiosensitization with a dose enhancement factor of 1.15 calculated at 10% cell survival relative to RT alone. Conclusion: AuNPs conjugated to anti-FRa Ab sensitize triple negative breast cancer cells to radiation and present a viable strategy to target cancer cells at the molecular level.