ИСТИНА

Modular nanotransporters (MNTs) are a drug delivery system designed for targeted cancer treatment [1]. The endosomolytic module of MNTs facilitates pHdependent pore formation in endosomes, which ensures the release of the MNT along with the delivered active component into the cytosol of the target cell following receptor-mediated endocytosis. The membranolytic activity of the module can be assessed by its ability to cause leakage of the contents of phosphatidylcholine liposomes loaded with a dye in a concentration that causes fluorescence selfquenching [2]. To study the kinetics of the process, we used a sulfo-cyanine dye, the fluorescence of which does not depend on pH. Using this approach, we measured and analyzed the kinetics of the early stages of membranolytic action of MNTs under different conditions for the first time. Our results helped us better understand the kinetics of the early stages of interaction of MNTs with the phosopholipid bilayer and demonstrated the conditions that are more suitable for further analysis.