VERFAHREN ZUM CHARAKTERISIEREN VON PROBEN VON SEKUNDÄRLICHT EMITTIERENDEN PARTIKELN

摘要

The method is well suited for single molecule observation. A fluorescence or Raman signal from single molecules is detected by photon counting. The sequence of detected photons is divided into counting intervals by defining the end of a counting interval when a predefined number of photons has been counted. For the photons from every counting interval, stochastic variables are determined like fluorescence decay time, anisotropy of the observed signal, etc., which are characteristic for the molecules. A multidimensional histogram is constructed as a function of the stochastic variables, whereby the histogram is built up using values of the variables determined from each counting interval. Regions of the histogram can be used to determine how the molecules are distributed in respect to binding sites, etc. The signal from selected regions of the histograms can then be chosen for further selective analysis to give species specific results.