Pyridine-biquinoline-metal complexes for sensing pyrophosphate and hydrogen sulfide in aqueous buffer and in cells

Anal Chem. 2015 Mar 3;87(5):2678-84. doi: 10.1021/ac504536q. Epub 2015 Feb 23.

Abstract

Herein, we report a new pyridine-biquinoline-derivative fluorophore L for effectively sensing pyrophosphate (PPi) and monohydrogen sulfide (HS(-)) in aqueous buffer and in living cells. L could selectively coordinate with metal ions (M(n+)) in Groups IB and IIB to form L-M(n+) complexes with 1:1 stoichiometry, resulting in fluorescence quenching via photoinduced electron transfer (PET) mechanism. L-Zn(2+) complex was applied to competitively coordinate with PPi to form a new "ate"-type complex, turning on the fluorescence by a 21-fold-increase. The limit of detection (LOD) of this assay for PPi detection in aqueous buffer is 0.85 μM. L-Cu(2+) complex was applied for highly selective detection of HS(-) with an excellent sensitivity by 25-fold decomplexation-induced fluorescence increase. LOD of L-Cu(2+) complex for HS(-) detection in aqueous buffer is 2.24 μM. With the in vitro data obtained, we successfully applied these two complexes for sequential imaging Zn(2+) and PPi, Cu(2+) and HS(-) in living cells, respectively. Since PPi and HS(-) occur in vascular calcification in positive correlation, our multifunctional probe L might help doctors to more precisely diagnose this disease in vivo in the future. For example, we could use radioactive tracer L-(64)Cu for qualitative and quantitative positron emission tomography/computed tomography (PET/CT) imaging of HS(-) in vivo.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Buffers
  • Coordination Complexes / chemistry*
  • Copper / chemistry*
  • Diphosphates / analysis*
  • Fluorescent Dyes / chemistry
  • Hep G2 Cells
  • Humans
  • Hydrogen Sulfide / analysis*
  • Limit of Detection
  • Molecular Structure
  • Pyridines / chemistry*
  • Quinolines / chemistry*
  • Spectrometry, Fluorescence
  • Water / chemistry
  • Zinc / chemistry*

Substances

  • Buffers
  • Coordination Complexes
  • Diphosphates
  • Fluorescent Dyes
  • Pyridines
  • Quinolines
  • Water
  • diphosphoric acid
  • Copper
  • Zinc
  • pyridine
  • Hydrogen Sulfide