Synthesis of Truncated DNA Aptamer and Its Application to an Electrochemical Biosensor Consisting of an Aptamer and a MXene Heterolayer for Yellow Fever Virus

Yellow fever virus (YFV) is an acute infectious virus with high morbidity and mortality risks during the toxic phase. Early diagnosis and suppression are essential because YFV has no precise treatment. With the aim of detecting YFV, we fabricated a highly sensitive electrochemical biosensor comprised with a truncated DNA aptamer/MXene heterolayer. The synthesized DNA aptamer was prepared by systematic evolution of ligands using the exponential enrichment (SELEX) technique, which can specifically detect the YFV NS1 protein. MXenes increase the electrical sensitivity and the possibility of attachment of aptamers by widening the surface area. The aptamer-cutting process which called a truncation process can reduce the production cost of biosensors. The biosensor performance was evaluated using electrochemical methods, cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS). The limit of detection (LOD) was 2.757 pM for YFV diluted in phosphate-buffered saline (PBS) and 2.366 pM for YFV diluted in 10% human serum, proving that the biosensor specifically binds to YFV through selectivity evaluation. This biosensor can be a valuable tool for the early diagnosis of YFV, enabling timely intervention as well as facilitating the control and prevention of yellow fever outbreaks.