Measurement of surface concentration of fluorophores by fluorescence fluctuation spectroscopy.
Fluorescence fluctuation spectroscopy is applied to study molecules passing through a small observation volume, usually subjected to diffusive or convective motion in a liquid phase. We suggest that such a technique could be used to measure the areal absolute concentration of fluorophores deposited on a substrate or embedded in a thin film, with a resolution of a few micrometers. The principle is to translate the solid substrate in front of a confocal fluorescence microscope objective and to record the subsequent fluctuations of the fluorescence intensity. The validity of this concept is investigated on model substrates (fluorescent microspheres) and DNA biochips.
Delon
A
A
Laboratoire de Spectrométrie Physique (UMR CNRS-UJF 5588), Université Grenoble 1, Boîte Postale 87, 38402 Saint Martin d'Hères, France. adelon@ujf-grenoble.fr
Derouard
J
J
Delapierre
G
G
Jaffiol
R
R