Ical signals. The proof shows that inside populations of EVs, important properties like morphology, composition and content GLUT4 Inhibitor manufacturer differ substantially. Hence, measuring EV heterogeneity is paramount to our understanding of how EVs influence physiological and pathological functions of their target cells. Hence far, devising productive methods for measuring EV heterogeneity remains a global challenge. Strategies: We present, for the first time, a study from the molecular and structural composition of individual EVs, subpopulations of EVs and entire populations of EVs employing resonance enhanced atomic force microscope infrared spectroscopy (AFM-IR). This strategy is labelfree, has ultra-high sensitivity and has the energy to measure EV heterogeneity. EVs have been isolated from placenta stem cells utilizing ultrafiltrationFriday, 04 Mayand after additional purification making use of the further size-exclusion chromatography column and each strategies had been compared. Benefits: We demonstrated for the initial time the possibility to characterise individual EV at nanoscale, EV populations and showed the essential differences in their composition depending on extraction protocols heterogeneity. Ultra-high resolution of AFM-IR that permits probing of various points on individual EVs is crucial to develop new extraction and separation protocols for EVs and to unlock their complete therapeutic and diagnostic potential. Our method outperforms other solutions for vesicles characterization offering unmatched resolution (single vesicle) and is “probe free”, hence it avoids bias and resolution limitations of molecular probes. Summary/Conclusion: The AFM-IR is advancing the EV field forward by revealing their molecular constituents and structures, too as enabling purity assessment of EV preparations. The information presented within this study suggest AFM-IR can transform current protocols for interrogating EV composition and structures, and assessing EV purity. This nanoscale strategy can be created into a powerful screening tool for detecting certain EV “fingerprints” which might be linked with pathology by correlating the structural variations to biomarkers, addressing unmet clinical needs in illnesses where early diagnosis is critical, for example many sclerosis or cancer.as a consequence of (1) competition in between capture and labeling antibody in TRFIA when the same antibody is applied, and (two) a non-linear connection amongst refractive index-based and labeling-based detection. Our benefits indicate that outcomes of diverse quantitative phenotyping approaches need to be addressed with care. For that reason, we advise to translate the outcomes into typical antigen density on detected EVs to allow the comparison of final results. Funding: This work was supported by the Cancer-ID perspectief plan of NWO Applied and Engineering Sciences [Project #14197].OF12.Proximity assays for detection and characterization of exosomes Ehsan Manouchehri; Alireza Azimi; Qiujin Shen; Masood KamaliMoghaddam Department of Immunology, Genetics and Pathology, IGP Uppsala University, Uppsala, SwedenOF12.Membrane protein quantification on extracellular vesicles by surface plasmon resonance imaging and time-resolved fluorescence immunoassay Elmar Gool1; Frank A.W Coumans2; Janne Leivo3; Mirella Vredenbregt – van den Berg4; Auguste Sturk5; Ton G. van Leeuwen2; Rienk Nieuwland5; Guido W. Jenster4 Department of Biomedical Physics and Engineering (BMEP) Division of Clinical Chemistry (LEKC) CYP3 Activator manufacturer Academic Healthcare Center, Amsterdam, The Netherla.