Photoacoustic detection of follicular thyroid carcinoma using targeted Nano-Au-Tripods

Follicular thyroid carcinoma (FTC) is the second most common form of thyroid malignancy, and it is associated with more aggressive growth and worse long-term survival outcomes relative to papillary thyroid carcinoma (PTC). Reliable approaches to preoperative FTC detection, however, remain to be established. Herein, a targeted Affibody-Au-Tripod nanoprobe was developed and successfully utilized to facilitate the targeted photoacoustic imaging (PAI) of epidermal growth factor receptor (EGFR)-positive cells and tumors. These Affibody-Au-Tripods were found to be highly sensitive and specific for cells expressing EGFR when used as a PA contrast agent in vitro, and studies conducted in an FTC-133 subcutaneous tumor model system in mice further revealed that these Affibody-Au-Tripods were able to specifically target these EGFR-expressing tumors while providing a strong photoacoustic signal in vivo. Importantly, these nanoprobes exhibited negligible cytotoxicity and robust chemical and physical stability, making Affibody-Au-Tripods promising candidates for targeted PAI-based FTC diagnosis. In addition, these nanoprobes have the potential to facilitate the individualized treatment of patients harboring EGFR-positive tumors.