Patent ID: 8269965
Filing Date: 2012-09-18
Classification: G01N

Abstract:
1. A method for analyzing a sample involving detecting radiation from particles or molecules in a measurement volume of the sample, the method comprising the steps of: measuring by detection means, in a repetitive mode, a number of photon counts per time interval of defined length, determining an experimental distribution function of the number of photon counts measured per time interval, determining a distribution function of specific brightness of the particles or molecules based on the experimental distribution function of the number of photon counts measured, by fitting an expected distribution function of the number of photon counts against the experimental distribution function of photon counts, wherein the expected distribution function of the number of photon counts is calculated using characteristics of a spatial brightness function, employing values of volumes of sections of the measurement volume corresponding to a selected set of values of the spatial brightness function and considering the volumes as variables depending on modeling parameters of the spatial brightness function, and selecting the values of these modeling parameters which yield the closest fit between the experimentally determined and the expected distribution of the number ofphoton counts, wherein the particles or molecules can be grouped into species distinguished by their specific brightness, wherein at least one of the species is luminescent, and wherein luminescence properties of the particle species are varied by conjugating the particle species with a first molecule capable of binding to a luminescently labeled second molecule.