Quantitative Analysis of Biomarkers Using G-Quadruplex-Hemin as a Catalase Enzyme

Nucleic acid biomarkers are useful tools that can give diagnoses, indicate prognosis, and monitor the effectiveness of therapy in various diseases. The quantitative analysis of oligonucleotides provides direct evidence that aids in treatment planning and therapy for these conditions, but current methodologies of analysis are costly due to calibration and require high- end laboratory equipment. To bypass these shortcomings, our experiment utilizes stoichiometry and the G-quadruplex-hemin complex, which can be engineered to follow a target-probe binding model that catalyzes hydrogen peroxide decomposition based on the amount of the target oligonucleotide sequence in the solution. Oxygen gas is released during the decomposition reaction, forming bubbles in the solution. The results can be interpreted from the quantity of bubbles present in the solution with a higher amount of bubbles signaling a higher presence of the nucleic acid biomarker, a cost-effective and widely applicable method of quantitative analysis. Further experiments are underway in order to finetune this model and produce a significant difference in bubble production between controls and samples containing oligonucleotides. Various factors such as buffer types, presence of surfactants, and concentration of reactants can be adjusted to improve the system.