Abstract: Three schemes of immunochromatographic serodiagnosis are considered and compared experimentally to determine the specific antibodies that act against the recombinant antigen of Brucella abortus (superoxide dismutase). The considered schemes differ in the order of immunoreagents interacting with the membranes and accordingly in the composition of the detected complexes. As a label, fluorescent nanocrystals were used quantum dots which allow more sensitive detection than traditional gold nano particles. The manufactured test systems were used to test the samples of blood sera of cows with confirmed Brucellosis. The obtained results demonstrated that the highest signal value is achieved in the scheme when the antigen is immobilized on the quantum dot’s surface and on the working membrane of the test system and the detected complexes are formed due to the presence of several valencies in antibodies.