A detection instrument for enhanced-fluorescence and label-free imaging on photonic crystal surfaces

Opt Express. 2009 Jul 20;17(15):13222-35. doi: 10.1364/oe.17.013222.

Abstract

We report on the design and demonstration of an optical imaging system capable of exciting surface-bound fluorophores within the resonant evanescent electric field of a photonic crystal surface and gathering fluorescence emission that is directed toward the imaging objective by the photonic crystal. The system also has the ability to quantify shifts in the local resonance angle induced by the adsorption of biomolecules on the photonic crystal surface for label-free biomolecular imaging. With these two capabilities combined within a single detection system, we demonstrate label-free images self-registered to enhanced fluorescence images with 328x more sensitive fluorescence detection relative to a glass surface. This technique is applied to a DNA microarray where label-free quantification of immobilized capture DNA enables improved quality control and subsequent enhanced fluorescence detection of dye-tagged hybridized DNA yields 3x more genes to be detected versus commercially available microarray substrates.

Publication types

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

MeSH terms

  • Adsorption
  • Animals
  • Biosensing Techniques / instrumentation*
  • Crystallization
  • Glass
  • Humans
  • Lasers
  • Metals / chemistry
  • Microscopy, Fluorescence / methods*
  • Nucleic Acid Hybridization
  • Oligonucleotide Array Sequence Analysis
  • Optics and Photonics*
  • Photons
  • Quality Control
  • Surface Plasmon Resonance / methods

Substances

  • Metals