Dual-Targeting Nanoprobe for Early Diagnosis of Pheochromocytoma Though Coinstantaneous Identification of Circulating Tumor Cells

Circulating tumor cells (CTCs) play a pivotal role in the early diagnosis of pheochromocytoma (PCC). Herein, we fabricated a new dual-targeting nanoprobe for coinstantaneous identification of rare PCC-CTCs from peripheral blood via targeting the norepinephrine transporter (NET) and somatostatin receptor SSTR2 overexpressed on the surface of PCC cells. Meta-iodobenzylguanidine (MIBG) functionalized magnetic Fe₃O₄ and octreotide (DOTA) decorated signal amplification Ag@SiO₂ nanosphere were used to capture and detect PCC-CTCs by binding to NET and SSTR2. The proposed dual-targeting sensor achieved good reproducibility and high sensitivity for the monitoring of PC12 in the concentration range from 5 to 5 × 10⁴ cells mL^–1, with detection limits of 2 cell/mL. This strategy opens a new approach for simple, sensitive, and rapid determination of PCC biomarkers, which shows great potential in early diagnosis, prognosis, and therapeutic evaluation of PCC.