biostudies-literatureLi CShanghai Municipal Science and Technology Major ProjectScience and Technology Commission of Shanghai MunicipalityChina National Postdoctoral Program for Innovative TalentsFund of Fudan University and Cao'ejiang Basic ResearchNational Natural Science Foundation of ChinaShanghai Municipal Health Commission ProjectNational Key Research and Development Program of ChinaStarlight Program Sailing Special Projecte16607https://www.ebi.ac.uk/biostudies/studies/S-EPMC12866695biostudies-literatureUnknown13(7)In vivo optical imaging advances antibody-drug conjugate (ADC) optimization by enabling real-time monitoring of biological stimulus-responsive drug behavior. Ratiometric probes, incorporating orthogonal wavelength-encoded multicolor detection and stimuli-cleavable linkages, are preferred over single-color strategies. Here, the synthesis of n501-CYMMAF (cyanine-decorated Monomethylauristatin F) is described as a novel ratiometric theranostic agent for dual efficacy in ovarian metastasis treatment and in situ treatment response monitoring. With low-dose administration (2.5 mg kg^-1), exceptional target affinity (EC_{50(n501-CYMMAF)} = 1.17 nm), and favorable biosafety (delivery to tumor-parts only), n501-CYMMAF enables experimental verification of treatment-evading metastatic cell populations through in situ fluorescent tracking, providing crucial insights into tumor recurrence pathways and judgement of treatment terminal point. In general, n501-CYMMAF represents a prototype for next-generation smart theranostics, integrating treatment and endpoint assessment to offer a platform for precision metastasis management.Advanced science (Weinheim, Baden-Wurttemberg, Germany)NIR Ratiometric Fluorescent Antibody-Drug Conjugate for Metastatic Ovarian Cancer Theranostics and Treatment Response Monitoring.PMC128666958232200124FCB0923XD14008002024YFA180310082394450924593013227098420244Y005882495204BX2024007623QA140120024YF2706100ZD2021CY001Yang ZLi CXie YYing TWang GYu ZWu YPu TShi YfalseNIR Ratiometric Fluorescent Antibody-Drug Conjugate for Metastatic Ovarian Cancer Theranostics and Treatment Response Monitoring.In vivo optical imaging advances antibody-drug conjugate (ADC) optimization by enabling real-time monitoring of biological stimulus-responsive drug behavior. Ratiometric probes, incorporating orthogonal wavelength-encoded multicolor detection and stimuli-cleavable linkages, are preferred over single-color strategies. Here, the synthesis of n501-CYMMAF (cyanine-decorated Monomethylauristatin F) is described as a novel ratiometric theranostic agent for dual efficacy in ovarian metastasis treatment and in situ treatment response monitoring. With low-dose administration (2.5 mg kg^-1), exceptional target affinity (EC_{50(n501-CYMMAF)} = 1.17 nm), and favorable biosafety (delivery to tumor-parts only), n501-CYMMAF enables experimental verification of treatment-evading metastatic cell populations through in situ fluorescent tracking, providing crucial insights into tumor recurrence pathways and judgement of treatment terminal point. In general, n501-CYMMAF represents a prototype for next-generation smart theranostics, integrating treatment and endpoint assessment to offer a platform for precision metastasis management.2026-01-01T00:00:00Z2026 Feb2026-06-30T03:28:46.962Z2026-06-30T03:22:32.455ZS-EPMC128666954131380210.1002/advs.202516607