Electrochemical immunoanalysis of cardiac myoglobin

Methods of myoglobin determination based on electrochemical analysis by means of analysis of electrochemical parameters of modified electrodes have been proposed. The method of direct detection is based on interaction of myoglobin with anti-myoglobin with subsequent electrochemical registration of this hemoprotein. The electrode surface was modified by a membrane-like synthetic didodecyldimethylammonium bromide (DDAB), gold nanoparticles and antibodies to human cardiac myoglobin the electrochemical reduction of myoglobin heme was registered provided that the antigen (myoglobin) was present in the samples. The reaction of myoglobin binding to antibodies immobilized on the electrode surface was also registered using electrochemical impedance spectroscopy. The study of electro analytical characteristics revealed high specificity and sensitivity of the developed method. The biosensor was characterized by low detection limit and a high working range of the detected concentrations from 17.8 to 1780 ng/ml (from 1 to 100 nM). The method of myoglobin determination based on a signal of gold nanoparticles has also been proposed. The signal was detected with stripping voltammetry. There was a change in the cathodic peak area and the peak height of gold oxide reduction for the electrodes with antibodies and the electrodes with the antibody-myoglobin complex.