Our group’s research focuses on various aspects of functional engineered DNA molecules – deoxyribozymes and aptamers – from their selection, characterization and optimization to their application for bioanalysis. Deoxyribozymes are DNA molecules exhibiting catalytic properties for a number of chemical transformations, from phosphodiester bond cleavage to Diels Alder reactions. They have a potential to serve as “green” catalysts, RNA cleaving anti-cancer agents, or for detection of ions and biomolecules. Aptamers can be viewed as receptors or antibodies made of DNA. Their ability to tightly and selectively bind a ligand (small molecule, protein, cell, etc.) is explored in designing chemical sensors and/or constructs with gene expression control capabilities. We use both types of functional DNA as a scaffold to design multicomponent probes that self-assemble in response to a specific nucleic acid target and report the target’s presence. The probes exhibit advantages of cost-efficient and straightforward design, which makes them easily optimizable and fined-tunable, high selectivity of nucleic acid recognition, ability to interrogate even highly structured nucleic acids, and a variety of signal readouts including a color change. Our goal is to employ the probes to advance “on-site” (point-of-care) diagnostics of bacterial and viral pathogens, as well as to use them in biochemical, biomedical and environmental research for instantaneous monitoring of specific nucleic acid sequences and for detecting the presence and/or abundance of modified bacterial strains or different bacterial species co-populating the same culture.