Sensitive biosensor for detection oncogenic miRNA-21

Abstract

The aim of this study was to prepare a sensitive electrochemical biosensor for detection of oncogenic miRNA-21 as a potential biomarker for early detection of cancer. MicroRNAs (miRNAs) are small noncoding RNA, which play an important role in the regulation of gene expression. miRNAs are present in extracellular fluids like urine, serum, etc. in extremely low concentration. It is important for the biosensor to detect extremely low concentrations of specific miRNA as potential biomarkers. The aim of this experiment was designing, preparing and optimizing a sensitive and selective biosensor for the detection of miRNA-21. A biosensor was prepared to detect the lowest concentration of miRNA-21 in the sample. The linear concentration range for the calibration curve was 1 fM to 10 nM. LOD was 1 fM and obtained from the regression equation was 3.2 zM and LOQ was 10.8 zM. Subsequently, prepared biosensor was measured in artificial urine (AU) samples to verify the functioning of the sensor in induced real conditions. The results showed a minimal effect of the matrix for the determination of the target miRNA.