Ultrasensitive fluorescent responses of water-soluble, zwitterionic, boronic acid-bearing, regioregular head-to-tail polythiophene to biological species

Chemistry. 2008;14(5):1648-53. doi: 10.1002/chem.200701376.

Abstract

Water-soluble regioregular head-to-tail zwitterionic fluorescent conjugated boronic acid-bearing polythiophene (polymer 2) was prepared through a postpolymerization quaternization of a pyridine group of 3-pyridineboronic acid with bromide groups of regioregular head-to-tail poly(3-bromohexylthiophene) (polymer 1). Titration of monosaccharides, lactose, ascorbic acid, or dopamine with 0.1 M phosphate buffer (pH 7.4), containing 4.0 microM of polymer 2, results in significant concentration-dependent quenching of the polymer fluorescence. The polymer displays an optimum response to the biological species at pH 7.0. The binding constants of polymer 2 with mannose, fructose, glucose, galactose, vitamin C, dopamine, and lactose are 3.33 x 10(4), 1.13 x 10(5), 1.23 x 10(5), 1.69 x 10(5), 3.17 x 10(5), 3.27 x 10(5), and 4.60 x 10(5), respectively.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Ascorbic Acid / chemistry
  • Binding Sites
  • Biosensing Techniques / methods*
  • Boronic Acids / chemistry*
  • Bromides / chemistry
  • Buffers
  • Dopamine / chemistry
  • Fluorescent Dyes / chemistry*
  • Hydrogen-Ion Concentration
  • Lactose / chemistry
  • Models, Chemical
  • Monosaccharides / chemistry
  • Polymers / chemical synthesis*
  • Pyridines / chemistry*
  • Solubility
  • Spectrometry, Fluorescence
  • Spectrophotometry, Ultraviolet
  • Thiophenes / chemical synthesis*
  • Water / chemistry*

Substances

  • 3-pyridineboronic acid
  • Boronic Acids
  • Bromides
  • Buffers
  • Fluorescent Dyes
  • Monosaccharides
  • Polymers
  • Pyridines
  • Thiophenes
  • Water
  • polythiophene
  • Lactose
  • Ascorbic Acid
  • Dopamine