Promiscuous dye binding by a light-up aptamer: application for label-free multi-wavelength biosensing

Chem Commun (Camb). 2021 Apr 18;57(30):3672-3675. doi: 10.1039/d1cc00594d. Epub 2021 Mar 16.

Abstract

Light-up DNA aptamers are promising label-free signal-transducers for biosensing applications due to their high chemical stability and low synthetic cost. Herein, we demonstrate that a dapoxyl DNA aptamer DAP-10-42 can be converted into a sensor generating a fluorescence signal at different wavelengths in the range of 500-660 nm depending on the dye that is present. This results from the discovered promiscuity of DAP-10-42 in binding fluorogenic dyes including arylmethane dyes. We have designed a split DAP-10-42 aptasensor for the detection of a katG gene fragment from Mycobacterium tuberculosis with a point mutation causing isoniazid resistance. Efficient interrogation of the gene fragment after nucleic acid sequence-based amplification (NASBA) is achieved directly in a protein-containing NASBA sample. This report lays a foundation for the application of the DAP-10-42 aptamer as a versatile sensing platform.

MeSH terms

  • Aptamers, Nucleotide / chemistry*
  • Bacterial Proteins / analysis*
  • Bacterial Proteins / genetics
  • Binding Sites
  • Biosensing Techniques*
  • Catalase / analysis*
  • Catalase / genetics
  • Fluorescent Dyes / chemistry*
  • Molecular Structure
  • Mycobacterium tuberculosis / genetics
  • Point Mutation

Substances

  • Aptamers, Nucleotide
  • Bacterial Proteins
  • Fluorescent Dyes
  • Catalase
  • katG protein, Mycobacterium tuberculosis