Electrochemical self-signal switch for determination of KRAS gene employing riboflavin 5'-adenosine diphosphate functionalized MoS2 nanosheets

An electrochemical self-signal switch was designed for direct sensing of KRAS gene associated with lung cancer based on riboflavin 5'-adenosine diphosphate (RADP) functionalized MoS2 nanosheets obtained by simple ultrasonication approach. RADP displayed favorable dispersive capacity for acquiring highly dispersed MoS2 nanosheets in aqueous medium. The obtained RADP/MoS2 nanocomposite demonstrated outstanding electrochemical redox activity and was adopted as the platform for the self-signal sensing of DNA immobilization and hybridization. The self-signal decreased when the probe ssDNA was immobilized on the acquired RADP/MoS2 nanocomposite by virtue of the noncovalent pi-pi interaction between the conjugated nanocomposite and nucleic acid bases. After the hybridization, the formed dsDNA could be released off the surface of the conjugated nanocomposite as a result of the base burying, accompanied with the regeneration of the self-redox signal. Electrochemical self-signal response increased with the target DNA concentration from 1.0 x 10(-18) to 1.0 x 10(-8) mol/L, and a detection limit of 2.7 x 10(-19) mol/L was evaluated. Simultaneously, the developed DNA determination interface manifested remarkable specificity and superior steadiness. The proposed detection scheme is worth to popularize and has the potentiality for the implementation of various morbigenous gene without complex label steps.

Automated summary

An electrochemical self-signal switch was designed for direct sensing of the KRAS gene associated with lung cancer. The switch was based on MoS2 nanosheets functionalized with riboflavin 5'-adenosine diphosphate (RADP) obtained through ultrasonication. The RADP/MoS2 nanocomposite showed excellent electrochemical activity and was used as a platform for DNA immobilization and hybridization. The proposed detection scheme demonstrated high sensitivity, specificity, and stability.