BBN conjugated GNPs: a new targeting contrast agent for imaging of breast cancer in radiology.

Using of targeted contrast agents in X-ray imaging of breast cancer can improve the accuracy of diagnosis, staging, and treatment planning by providing early detection and superior definition of tumour volume. This study demonstrates a new class of X-ray contrast agents based on gold nanoparticles (GNPs) and bombesin (BBN) for imaging of breast cancer in radiology. GNPs were synthesised in spherical shape in the size range of 15 ± 2 nm and conjugated with BBN followed by coating with polyethyleneglycol (PEG). The in vitro and in vivo behaviour of PEG-coated GNPs-BBN conjugate was investigated performing cytotoxicity, binding, and internalisation assays as well as biodistribution and X-ray imaging studies in mouse bearing breast tumour. Cytotoxicity study showed biocompatibility of the prepared bioconjugate. The binding and internalisation studies using T47D cell line approved the targeting ability of new agent. The biodistribution study showed the considerable accumulation of prepared conjugate in breast tumour in mouse model. The breast tumour was clearly visualised in X-ray images taken from the mouse model. The results showed the potential of PEG-coated GNPs-BBN conjugate as a contrast agent in X-ray imaging of breast tumour in humans that need further investigations.