Modular Albumin-Chaperoned NIR-II Nanofluorophores Enables Pan-Ovarian Cancer Imaging Across Multiscale Tumor Models

Abstract

Ovarian cancer remains the most lethal gynecological malignancy, primarily due to late-stage diagnosis and the challenges of achieving complete cytoreduction. While fluorescence image-guided surgery (FIGS) offers intraoperative visualization, current clinical agents are limited by insufficient brightness, rapid photobleaching, and poor molecular selectivity, particularly in the near-infrared window. Here, we report the rational modular design of ultrabright NIR-II semiconducting polymer (SP) nanofluorophores for high-fidelity ovarian cancer imaging. By nanoconfining of a representative hydrophobic SP within a functional albumin matrix induces a "chaperone" effect that suppresses aggregation-induced quenching and shifts emission in the NIR-II window (1000-1250 nm). This platform integrates a dual-receptor targeting strategy, leveraging intrinsic albumin-receptor interactions (GP60 and SPARC) alongside folate receptor alpha (FR) functionalization. This synergistic approach enables pan-ovarian cancer imaging by ensuring high-affinity binding across diverse tumor phenotypes, regardless of heterogeneous receptor expression. Across a multiscale validation framework, the nanofluorophores demonstrate efficient receptor-mediated endocytosis in 2D cultures and deep interstitial penetration in 3D tumor spheroids. Furthermore, microfluidic tumor-on-chip models incorporating endothelial-like fenestrations confirm controlled extravasation and targeting under physiological shear stress. 3D bioprinted tumor phantoms and ex vivo porcine ovary tissues further confirm that BSA-FA@SP2 provides superior lesion delineation and signal-to-background ratios compared to indocyanine green, a clinical standard. Importantly, the nanofluorophores exhibit excellent hemocompatibility, with minimal hemolysis and negligible complement activation, indicating a non-immunogenic, stealth profile. Collectively, this work establishes albumin-shielded NIR-II nanofluorophores as a robust platform for precision intraoperative pan-ovarian imaging and advances the translational potential of nanotechnology-enabled surgical oncology.