Zhang, TiCui, HuizhongFang, Chia-YiCheng, KunChang, Huan-ChengForrest, M. Laird2017-06-272017-06-272015-03Zhang, T., Cui, H., Fang, C.-Y., Cheng, K., Yang, X., Chang, H.-C., & Forrest, M. L. (2015). Targeted Nanodiamonds as Phenotype Specific Photoacoustic Contrast Agents for Breast Cancer. Nanomedicine (London, England), 10(4), 573–587. http://doi.org/10.2217/nnm.14.141https://hdl.handle.net/1808/24643AIM: The aim is to develop irradiated nanodiamonds (INDs) as a molecularly-targeted contrast agent for high resolution and phenotype-specific detection of breast cancer with photoacoustic (PA) imaging. MATERIALS & METHODS: The surface of acid treated radiation-damaged nanodiamonds was grafted with polyethylene glycol (PEG) to improve its stability and circulation time in blood, followed by conjugation to an anti-Human epidermal growth factor receptor-2 (HER2) peptide (KCCYSL) with a final nanoparticle size of ca. 92 nm. Immunocompetent mice bearing orthotopic HER2 positive or negative tumors were administered INDs and PA imaged using an 820-nm near infrared laser. RESULTS: PA images demonstrated that INDs accumulate in tumors and completely delineated the entire tumor within 10 hours. HER2 targeting significantly enhanced imaging of HER2-positive tumors. Pathological examination demonstrated INDs are non-toxic. CONCLUSIONS: PA technology is adaptable to low-cost bedside medicine, and with new contrast agents described herein, PA can achieve high resolution (sub-mm) and phenotype specific monitoring of cancer growth.NanodiamondPhotoacoustic ImagingContrast agentBreast CancerHER2Article10.2217/nnm.14.141PMC4703108openAccess