Self-Signal Electrochemical Monitoring of Hybridization of Nucleic Acids Based on Riboflavine Sodium Phosphate Decorated WS2 Nanosheets

In this work, the development of riboflavine sodium phosphate (RFSP) decorated WS2 nanosheets and their usability for electrochemical monitoring of hybridization of nucleic acids have been achieved. The RFSP molecules performed as highly efficient stabilizer for ultrasonically dispersing WS2 nanosheets in an aqueous solution, as well as providing the inherent self-redox signal for sensing DNA immobilization and hybridization. The probe ssDNA was noncovalently assembled on the fabricated RFSP/WS2 nanocomposite surface through the pi-pi interaction between the conjugated nanocomposite and nucleic acids bases. The formed dsDNA after the hybridization of the probe with the target could be released off the surface of the conjugated nanocomposite because of the burying of DNA bases. This constructed genosensor permits quantitative determination of PIK3CA gene in the range of 1.0 x 10(-16) to 1.0 x 10(-8) mol l(-1) with a detection limit as low as 2.1 x 10(-17) mol l(-1). The proposed platform exhibited a desirable differentiation capability against complementary, noncomplementary and base-mismatched sequences along with favorable stability and reproducibility. This approach of genosensing can provide a facile and rapid mode for DNA determination without the utilization of additional labels. (C) 2020 The Electrochemical Society (ECS). Published on behalf of ECS by IOP Publishing Limited.