Gold nanoparticle conjugation and tumor accumulation of a VEGF receptor-targeting peptidomimetic

Gold nanoparticles (GNPs) exhibit promising potential for both cancer treatment and diagnosis. While the conjugation with tumor-targeting peptides enhances GNP functionality, there remains a need for further exploration of GNP transport and accumulation within tumors in vivo. This study focuses on the synthesis, characterization, cell binding, and biodistribution of GNPs adorned with a peptide targeting vascular endothelial growth factor receptor (VEGFR)-1/-2, named VGB3. The synthesized naked and VGB3-conjugated GNPs underwent through characterization using UV–Vis, DLS, FTIR, and TEM. Cellular analysis through immunocytochemistry and flow cytometry revealed that VGB3 and GNP-VGB3 selectively bound to VEGFR-1/-2-expressing human umbilical vein endothelial cells (HUVECs) and murine 4T1 mammary carcinoma tumor cells, with no affinity observed for VEGFR-1/-2-deficient HL-60 acute myeloid leukemia cell line. SPECT imaging of whole animals demonstrated specific accumulation of fluorescein isothiocyanate (FITC)-VGB3-decorated GNPs in 4T1 tumors. These results affirm the suitability of cell-specific peptides for targeted GNP delivery, emphasizing their potential in biomedical applications and targeted therapeutics. Graphic abstract