METHOD OF MEASURING CONCENTRATION OF OXYGEN IN A SUBCUTANEOUS TUMOR OF EXPERIMENTAL ANIMALS Russian patent published in 2020 - IPC A61B5/05 G09B23/28 B82B1/00 

FIELD: medicine.

SUBSTANCE: invention refers to medicine, namely biomedicine, and can be used to measure oxygen concentration in a subcutaneous tumor of experimental animals. Experimental animals with subcutaneous engrafted tumor are preliminarily prepared, for this purpose animals are narcotized by intraperitoneal injection of zoletil solution in concentration 50–75 mg/kg with xylazine in concentration of 5–7.5 mg/kg. Providing access to a subcutaneous tumor of an animal, for which a skin is incised along the spinal line and the skin fold is separated from the tumor from adjacent tissues. Blood vessels are incinerated at incision points and the tumor is cleaned from the capsule by removing its upper layers. Method comprises forming a bath for examination of a skin fold and a subcutaneous musculature of an animal's back, for which the edges of the skin fold are lifted and fixed with the help of a suture material. Bath is filled with phosphate-saline buffer with pH 7.4. Method comprises preparation of measuring nanoelectrode, which is nanopipette filled with pyrolytic carbon with platinum deposited on it, with preliminary calibration of nanoelectrode in oxygen. Experimental animal is placed on a microscope object table. Measuring nanoelectrode is mounted in an intravital electrochemical module holder (IVEC module). Mutual positioning of the tumor and the measuring nanoelectrode is carried out, a silver chloride reference electrode is placed in a bath with a solution of a phosphate-salt buffer and connected to a measuring system. Potential is linearly sweep from -800 mV to +800 mV, step-by-step introduction of a nanoelectrode into a tumor at a given depth at a given angle and measuring current strength at potentials of -500 mV to -600 mV to determine the oxygen level at each step of immersing the nanoelectrode. Values of oxygen concentration in tumor by corresponding calibration curve are determined.

EFFECT: method enables determining the concentration of oxygen within a tumor of a living experimental animal at a given point with high spatial and temporal resolution by using a nanoelectrode at potential values from -500 mV to -600 mV relative to silver chloride reference electrode, which enables to obtain complete picture of oxygen distribution in tumor volume.

4 cl, 6 dwg, 1 ex