FIELD : medicine.SUBSTANCE : invention relates to biotechnology and medicine. Described is a method of detecting circulating targets in the blood of patients associated with a certain diagnosis. Solid phase is treated with biospecific reagents, the unreacted liquid phase is separated, incubated with the target associated with the certain diagnosis. Further, the solid phase is treated with a reporter, liquid and solid phases are separated. Solid phase is analyzed. Solid phase used is magnetic microparticles with covalently immobilized streptavidin molecules, biospecific reagent for first solid phase treatment is DNA-aptamer binding to surface by hybridization with biotin-labeled oligonucleotide 5' -CGTGGTTACAGTCAGAGGAG-3' -Bio, complementary to constant end portion of DNA-aptamer, and as reporter – another DNA-aptamer labeled with conjugate of same oligonucleotide with Ca-regulated photoprotein obelin.EFFECT : more sensitive, universal, express and technological bioluminescent method for detecting targets associated with a certain diagnosis in patient' s blood.1 cl, 3 dwg, 2 ex