ИСТИНА

Increasing the efficiency of drug delivery to target cells and organs is a key task of pharmacology. Bilayer lipid vesicles (liposomes) are among the drug carriers that have been intensively used for drug immobilization. pH-sensitive liposomes have great potential for biomedical applications, in particular as nanocontainers for the delivery of biologically active compounds to specific areas of the human body, since lower pH is typical for tumors, areas of inflammation, etc. A great number of pH-sensitive liposomes have been described, but, thereby, it is still a considerable challenge to prepare liposomes that could quickly release the encapsulated substance under small changes in the pH. We suggest the new type of pH-sensitive liposomes with embedded ampholytic molecular switch (AMS) with anionic and cationic groups attached to the opposite ends of the steroid core. The AMS is able to change the orientation in the lipid membrane depending on the acidity/basicity of the external solution, which is accompanied by disordering of the bilayer and rapid release of the encapsulated substance.