Chemists led by Eric Kool, Stanford University, USA, have developed seven fluorescent replacements for DNA bases and attached them to a single helix of a DNA-like oligomer for the detection of small vapor molecules.

The oligodeoxyfluorosides (ODFs) create a library of 2401 tetramer ODFs. The tetramers can be conjugated to poly(ethylene glycol) – polystyrene beads by an amide linkage allowing them to be incorporated into devices.

A quantitative color-change profile could be determined in the presence of vapor molecules, with a different ordering of the fluorophores along the ODF giving rise to different color changes. This gives sequence-based responses that are distinct for multiple classes of analytes and could be extended beyond the detection of simple compounds for use in detecting anything from souring milk to explosives.

• Polyfluorophores on a DNA Backbone: Sensors of Small Molecules in the Vapor Phase
  F. Samain, S. Ghosh, Y. N. Teo, E. T. Kool,
  Angew. Chem. Int. Ed. 2010, 49.
  DOI: 10.1002/anie.201002701
• F. Samain, S. Ghosh, Y. N. Teo, E. T. Kool,
  Angew. Chem. 2010, 122.
  DOI: 10.1002/ange.201002701