Ag2S quantum dot-based magnetic resonance/fluorescence dual-mode imaging nanoprobes for tumor diagnosis†

Abstract

Accurate tumor detection is crucial for the early discovery and subsequent treatment of small neoplastic foci. Molecular imaging, which combines non-invasiveness, high specificity, and strong sensitivity, excels in diagnosing early tumors and stands out among tumor diagnosis methods. Here, we introduced a dual-modal imaging probe capable of actively targeting tumor cells, suitable for both near-infrared (NIR) fluorescence and magnetic resonance imaging (MRI). Dendritic mesoporous silica was used as a carrier for the probe, encapsulating Ag₂S quantum dots (QDs) for NIR fluorescence imaging. Additionally, the probe conjugated the MRI contrast agent Gd-DOTA and cetuximab, which targeted EGFR on the tumor cell membrane surface, to achieve dual-modal imaging in the tumor area. This strategy provided a methodology for the accurate diagnosis of early-stage tumor lesions and guides precise lesion resection during surgery, offering significant potential for clinical application.