Overexpression of epidermal growth factor receptor (EGFR) is closely associated with a poor prognosis in non-small cell lung cancer (NSCLC), thus making it a promising biomarker for NSCLC diagnosis. Here, we conjugated a single-chain antibody (scFv) targeting EGFR with Fe₃O₄/Au nanoparticles to form an EGFR-specific molecular MRI bioprobe (scFv@Fe₃O₄/Au) to better detect EGFR-positive NSCLC tumors in vivo. In vitro, we demonstrated that the EGFR-specific scFv could specifically deliver Fe₃O₄/Au to EGFR-positive NSCLC cells. In vivo experiments showed that the accumulation of scFv@Fe₃O₄/Au in tumor tissue was detectable by magnetic resonance imaging (MRI) at the indicated time points after systemic injection. The T2W signal-to-noise ratio (SNR) of EGFR-positive SPC-A1 tumors was significantly decreased after scFv@Fe₃O₄/Au injection, which was not observed in the tumors of mice injected with BSA@Fe₃O₄/Au. Furthermore, transmission electron microscopy (TEM) analysis showed the specific localization of scFv@Fe₃O₄/Au in the SPC-A1 tumor cell cytoplasm. Collectively, the results of our study demonstrated that scFv@Fe₃O₄/Au might be a useful probe for the noninvasive diagnosis of EGFP-positive NSCLC.

表皮生长因子受体 (EGFR) 的过度表达与非小细胞肺癌 (NSCLC) 的不良预后密切相关，因此使其成为 NSCLC 诊断的有希望的生物标志物。在这里，我们将靶向 EGFR 的单链抗体 (scFv) 与 Fe ₃ O ₄ /Au 纳米颗粒结合形成 EGFR 特异性分子 MRI 生物探针（scFv@Fe ₃ O ₄ /Au），以更好地检测 EGFR 阳性 NSCLC 肿瘤活体。在体外，我们证明了 EGFR 特异性 scFv 可以将 Fe ₃ O ₄ /Au特异性递送至 EGFR 阳性 NSCLC 细胞。体内实验表明scFv@Fe ₃ O ₄在全身注射后的指定时间点，通过磁共振成像 (MRI) 可检测到肿瘤组织中的 /Au。scFv@Fe ₃ O ₄ /Au注射后EGFR阳性SPC-A1肿瘤的T2W信噪比（SNR）显着降低，这在注射BSA@Fe ₃ O ₄的小鼠肿瘤中未观察到/金。此外，透射电子显微镜 (TEM) 分析显示 scFv@Fe ₃ O ₄ /Au 在 SPC-A1 肿瘤细胞质中的特异性定位。总的来说，我们的研究结果表明，scFv@Fe ₃ O ₄ /Au 可能是 EGFP 阳性 NSCLC 无创诊断的有用探针。