pH-responsive fluorescence chemical sensor constituted by conjugated polymers containing pyridine rings

Luminescence. 2015 Dec;30(8):1308-12. doi: 10.1002/bio.2898. Epub 2015 Mar 31.

Abstract

Poly(p-pyridinium phenylene ethynylene)s (PPyPE) functionalized with alternating donor-acceptor repeat units were synthesized by a Pd-catalyzed Sonogashira coupling reaction between diethynyl monomer and di-iodopyridine for use as a pH-responsive fluorescence chemical sensor. The synthesized PPyPE, containing pyridine units, was characterized by FT-IR, (1)H and (13)C NMR, UV-visible and fluorescence spectroscopies. We investigated the relationship between changes of optical properties and protonation/deprotonation of PPyPE containing pyridine units in solution. Addition of HCl decreased and red-shifted the fluorescence intensity of the conjugated polymers that contained pyridine rings; fluorescence intensity of the polymers increased upon addition of NaOH solution. The synthesized PPyPE was found to be an effective and reusable chemical sensor for pH sensing.

Keywords: chemical sensor; conjugated polymers; fluorescence color change; pH sensing; pyridine units.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Fluorescence
  • Hydrogen-Ion Concentration
  • Magnetic Resonance Spectroscopy
  • Molecular Structure
  • Polymers / chemical synthesis
  • Polymers / chemistry*
  • Pyridines / chemistry
  • Pyridinium Compounds / chemical synthesis
  • Pyridinium Compounds / chemistry
  • Spectrometry, Fluorescence
  • Spectroscopy, Fourier Transform Infrared

Substances

  • Polymers
  • Pyridines
  • Pyridinium Compounds
  • poly(pyridinium phenylene)
  • pyridine