An electrochemical microRNA sensing platform based on tungsten diselenide nanosheets and competitive RNA-RNA hybridization

• Published in: Analyst (London) Vol. 142; no. 24; pp. 4843 - 4851
• Main Authors: Chen, Ying-Xu, Zhang, Wen-Jing, Huang, Ke-Jing, Zheng, Mingbo, Mao, Ya-Cen
• Format: Journal Article
• Language: English
• Published: England Royal Society of Chemistry 21.12.2017
• Subjects: Biosensing Techniques; Biosensors; Configurations; Electrochemical Techniques; Horseradish Peroxidase; Humans; Hybridization; Hydrogen Peroxide; Hydroquinone; MicroRNAs; MicroRNAs - analysis; MicroRNAs - blood; Nanosheets; Nanostructures; Nucleic Acid Hybridization; Peroxidase; Ribonucleic acid; RNA; Selenides; Target detection; Tungsten; Tungsten compounds
• ISSN: 0003-2654; 1364-5528
• DOI: 10.1039/c7an01244f

In this work, we report an ultrasensitive electrochemical biosensor for microRNA-21 (miRNA-21) detection by using a competitive RNA-RNA hybridization configuration. A biotinylated miRNA of the self-same sequence with the target miRNA is mixed with the samples, and allowed competition with the target miRNA for a thiolated RNA probe immobilized onto a tungsten diselenide (WSe ) nanosheet modified electrode. Thereafter the current response is obtained by forming the hybridized biotinylated miRNA with streptavidin-horseradish peroxidase (HRP) conjugates to catalyze the H O + hydroquinone (HQ) system. Benefiting from the high specific surface area of WSe nanosheets, the competitive hybridization configuration and the signal amplification of the H O + HQ detection system, the proposed assay exhibits a wide linear range of 0.0001-100 pM towards target miRNA with a detection limit of 0.06 fM (S/N = 3), and shows excellent discrimination ability for base-mismatched miRNA sequences. Therefore, the designed platform has promising prospects for the detection of miRNA in biomedical research and early clinical diagnosis.