Patent ID: 8906673

Claim:
A method for counting biomolecules in a sample comprising: labeling the biomolecules in the sample with a nanoparticle probe comprising a detectable nanoparticle; providing the labeled biomolecules on a transparent base material; automatically counting the nanoparticles including; automatically capturing an image of the nanoparticles; automatically detecting nanoparticles that have fluoresced on the image; and maintaining a count of discrete groups of nanoparticle probes or single nanoparticle probes, wherein counting the nanoparticles is considered counting of the target biomolecules; performing blinking analysis of nanoparticle fluorescence including: capturing a movie of an x-y location of the transparent base material; detecting nanoparticle fluorescence in each frame of the captured movie; maintaining a movie-based count of detected nanoparticle fluorescence over each frame in the captured movie to obtain an accurate total count of each detected nanoparticle and a time-varying intensity trace of each detected nanoparticle fluorescence; detecting background intensity values over each frame of the captured movie to obtain a time-varying background intensity trace; binning intensity values of the time-varying background intensity trace to obtain a distribution of background intensity values; and for each detected nanoparticle fluorescence: binning intensity values of the time-varying intensity trace of the detected nanoparticle fluorescence to obtain a distribution of intensity values associated with the nanoparticle fluorescence; and characterizing a nanoparticle population composition of the detected nanoparticle fluorescence based on an amount of overlap of the distribution of intensity values associated with the nanoparticle with the distribution of background intensity values and mean intensity values of the detected nanoparticle fluorescence.