Eriochrome Black T-Eu3+ Complex as a Ratiometric Colorimetric and Fluorescent Probe for the Detection of Dipicolinic Acid, a Biomarker of Bacterial Spores

Anal Chem. 2018 Mar 20;90(6):4221-4225. doi: 10.1021/acs.analchem.8b00576. Epub 2018 Mar 7.

Abstract

A novel ratiometric colorimetric and fluorescent dual probe based on Eriochrome Black T (EBT)-Eu3+ complex was designed to detect dipicolinic acid (DPA), a major constituent of bacterial spores, with high sensitivity and selectivity. UV-vis titration experiments demonstrated that EBT and Eu3+ ions formed a 1:1 coordination pair in water. In the presence of Eu3+ ions, the blue solution of EBT changed to magenta, however, upon the addition of DPA, the magenta color changed to blue immediately and characteristic fluorescence emission from DPA-Eu3+ complex was observed. In addition, the sensitivity of the system was further evaluated on Geobacillus stearothermophilus spores and as low as 2.5 × 105 spores were detected.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Azo Compounds / chemistry*
  • Biosensing Techniques / methods
  • Colorimetry / methods
  • Coordination Complexes / chemistry
  • Europium / chemistry*
  • Fluorescent Dyes / chemistry*
  • Geobacillus stearothermophilus / chemistry*
  • Geobacillus stearothermophilus / isolation & purification
  • Picolinic Acids / analysis*
  • Spectrometry, Fluorescence / methods
  • Spores, Bacterial / chemistry*
  • Spores, Bacterial / isolation & purification

Substances

  • Azo Compounds
  • Coordination Complexes
  • Fluorescent Dyes
  • Picolinic Acids
  • Europium
  • Eriochrome Black T
  • dipicolinic acid