Collagen IV-targeted phase-change nanoparticles illuminate early liver fibrosis staging via ultrasound molecular imaging

< 0.001). ROC analysis demonstrated high diagnostic accuracy for early fibrosis: an area under the curve (AUC) of 0.949 for distinguishing S0 from S1-S4 (sensitivity 85.5%, specificity 91.7%) and an AUC of 0.923 for separating S0-S1 from S2-S4 (sensitivity 90.7%, specificity 79.2%). To date, AC-IV-PFP@NPs represent the first type IV collagen-targeted UMI platform for liver fibrosis staging in rats, offering non-invasive, real-time assessment with high sensitivity for early-stage disease (S1-S2). This approach addresses the limitations of biopsy and conventional imaging and offers a promising and transformative approach for clinical fibrosis management.