Engineering Anti-MMP-9 Peptide-Modified Nanoparticles for Precision MRI Diagnosis of Endometriosis

Endometriosis diagnosis is often limited by the resolution of conventional imaging techniques (ultrasound/non-targeted MRI) as well as the invasiveness and recurrence risks associated with laparoscopy. To overcome these challenges, we developed anti-MMP-9 peptide-conjugated NaGdF₄@PEG-Cy5.5 nanoparticles (NPPCNs), which integrate NaGdF₄ cores to enhance T1 relaxivity and biocompatibility for MMP-9-targeted molecular imaging. In vitro studies confirmed both cytocompatibility and high-affinity MMP-9 binding. In vivo biodistribution, assessed through T1-weighted MRI and fluorescence imaging within 48 h post-injection, revealed significant nanoparticle accumulation in endometriotic lesions, with elevated signal intensity compared to controls. This MMP-9-targeted theranostic platform offers a non-invasive method for lesion detection, providing a novel approach for precise diagnosis and surgical navigation in endometriosis.