Single-molecule analysis of DNA immobilized on microspheres

Anal Chem. 2000 Aug 1;72(15):3678-81. doi: 10.1021/ac000129r.

Abstract

The formation and analysis of single molecules of fluorescently labeled DNA immobilized on polystyrene microspheres is described. Analysis by confocal fluorescence microscopy revealed single-step photobleaching, characteristic of a single fluorophore. Microspheres provide a means of locating single molecules by bright-field microscopy, prior to single-molecule detection. This allows the interrogation of single molecules without suffering the limitations of premature photobleaching. Statistical analysis of fluorescence intensities for >100 microspheres suggests attachment of DNA to micropsheres to be consistent with Poisson statistics.

MeSH terms

  • DNA / analysis*
  • Microspheres
  • Polystyrenes

Substances

  • Polystyrenes
  • DNA