Live cells imaging using a turn-on FRET-based BODIPY probe for biothiols

Biomaterials. 2014 Jul;35(23):6078-85. doi: 10.1016/j.biomaterials.2014.04.035. Epub 2014 May 1.

Abstract

We designed a red-emitting turn-on FRET-based molecular probe 1 for selective detection of cysteine and homocysteine. Probe 1 shows significant fluorescence enhancement after cleavage of the 2, 4-dinitrobenzensulfonyl (DNBS) unit from the fluorophore upon thiols treatment. The precursor of probe 1, BNM153, is a moderate quantum yield FRET dye which contributes a minimum emission leakage from its donor part. We synthesized this assembly by connecting a low quantum yield (less than 1%) BODIPY donor to a high quantum yield BODIPY acceptor via a 1, 3-triazine bridge system. It is noteworthy that the majority of the non-radiative energy loss of donor (BDN) was converted to the acceptor (BDM)'s fluorescence output with minimum leaks of donor emission. The fluorescence sensing mechanism of probe 1 was illustrated by fluorescence spectroscopy, kinetic measurements, HPLC-MS analysis and DFT calculations. Probe 1 is pH-independent at the physiological pH range. Finally, live cells imaging demonstrated the utility of probe 1 as a biosensor for thiols.

Keywords: Biothiols; Fluorescence; Fluorescence resonance energy transfer (FRET); Sensor; cysteine.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Boron Compounds / analysis*
  • Boron Compounds / chemistry*
  • Cysteine / metabolism*
  • Fluorescence Resonance Energy Transfer / methods*
  • HeLa Cells
  • Homocysteine / metabolism*
  • Humans
  • Microscopy, Fluorescence / methods
  • Molecular Imaging / methods*
  • Reproducibility of Results
  • Sensitivity and Specificity
  • Sulfhydryl Compounds / metabolism*

Substances

  • 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene
  • Boron Compounds
  • Sulfhydryl Compounds
  • Homocysteine
  • Cysteine