In our work, we are developing a material for an electrochemical sensor detecting cysteine and glutathione based on non-lithographic template synthesis consisting of an array of micron silver particles on a Ti substrate separated by a dielectric TiO2 xerogel with adjustable mutual removal. The array of microelectrodes has a number of advantages over planar electrodes consisting of a single conductive metal phase. The smaller the electrode area and the larger the anolyte flow due to diffusion to its surface, the more capacitive interference is leveled, and it becomes possible to determine concentrations of electroactive substances at low concentrations.
The use of such materials for the amino acids determination is promising due to the fact that the volume of biological samples (saliva), as a rule, is at the level of tens of microliters, and the use of this technology allows the manufacture of micron-sized sensors and rapid analysis at low amino acids concentrations. Also, the detection of biological substances in low concentrations will make it possible to make a clinical diagnosis at earlier stages of the disease. During the study of cyclovoltammograms, the possibility of using these materials to determine electroactive compounds with similar diffusion coefficients was shown.
The work carried out studies with cysteine and glutathione, since currently the identification of these amino acids in low concentrations in biological media is of great interest. These amino acids play an important role in cellular homeostasis, as well as those responsible for antioxidant activity in the cytoplasm of the cell, and the level of their content in saliva can serve as a criterion for the diagnosis of a number of diseases.