Preparation and Characterization of Aptamers Against O,p'-DDT

Int J Mol Sci. 2020 Mar 23;21(6):2211. doi: 10.3390/ijms21062211.

Abstract

The compound 1,1,1-trichloro-2-(p-chlorophenyl)-2-(o-chlorophenyl) ethane (o,p'-DDT) has been identified as one of the endocrine-disrupting chemicals causing adverse effects on wildlife and even humans through bioaccumulation. Its detection has become increasingly important. We have obtained candidate aptamers binding to o,p'-DDT by a systematic evolution of ligands by exponential enrichment (SELEX) protocol. Five out of seventeen candidate sequences were selected for preliminary characterization by SYBR Green I assay. One sequence with highest fluorescence response with o,p'-DDT, designated DDT_13, was chosen for further characterization. Its dissociation constant (Kd) was determined to be 412.3 ± 124.6 nM. DDT_13 exhibited low cross-binding activities on other tested small molecules. The good bioactivities of DDT_13 were demonstrated for the analysis of spiked lake water and tap water samples. This study provides a novel o,p'-DDT-specific probe for its future applications.

Keywords: AuNPs; SELEX; aptamer; biosensor; o,p’-DDT; real water sample.

MeSH terms

  • Aptamers, Nucleotide* / chemistry
  • Aptamers, Nucleotide* / genetics
  • Biosensing Techniques
  • DDT / antagonists & inhibitors*
  • Female
  • Gold / chemistry
  • Humans
  • Ligands
  • Male
  • Nanoparticles / chemistry
  • Nucleic Acid Conformation
  • SELEX Aptamer Technique
  • Sensitivity and Specificity
  • Water Pollutants, Chemical / analysis

Substances

  • Aptamers, Nucleotide
  • Ligands
  • Water Pollutants, Chemical
  • Gold
  • DDT
  • o,p'-DDT