Digital analyte analysis
View Patent ↗The invention generally relates to detecting target molecules.
1. A method of detecting a target nucleic acid molecule, the method comprising:
providing a plurality of aqueous droplets, wherein approximately 1% of the aqueous droplets comprise a target nucleic acid molecule;
providing a detector adjacent to a microfluidic channel, the detector configured to detect fluorescent signal above a threshold intensity level;
conducting a reaction involving the target nucleic acid molecule to produce a fluorescent signal above the threshold intensity level in the aqueous droplets containing the target nucleic acid molecule;
flowing the plurality of aqueous droplets through the microfluidic channel past the detector in an overlapping configuration; and
detecting the fluorescent signal to identify the aqueous droplets comprising the target nucleic acid molecule.
2. The method of claim 1 , wherein the target nucleic acid molecule is selected from the group consisting of: a nucleic acid, a protein, an antibody, an aptamer, a cell, and a microorganism.
3. The method of claim 1 , wherein prior to the providing step, the method comprises forming the plurality of aqueous droplets.
4. The method of claim 1 , wherein the plurality of aqueous droplets are in an immiscible fluid.
5. The method of claim 4 , wherein the immiscible fluid is oil.
6. The method of claim 5 , wherein the oil comprises a surfactant.
7. The method of claim 6 , wherein the surfactant is a fluorosurfactant.
8. The method of claim 5 , wherein the oil is a fluorinated oil.
9. The method of claim 1 , wherein a plurality of the aqueous droplets comprise no more than a single target nucleic acid molecule.
10. The method of claim 1 , wherein one or more aqueous droplets are empty.
11. A method of detecting a target nucleic acid molecule, the method comprising:
providing a plurality of non-single-file aqueous droplets, wherein approximately 1% of the aqueous droplets comprise a target nucleic acid molecule;
conducting a reaction involving the target nucleic acid molecule to produce a fluorescent signal above a threshold intensity level in the aqueous droplets containing the target nucleic acid molecule; and
flowing the plurality of non-single-file aqueous droplets through a microfluidic channel; past a fluorescent detector configured to detect fluorescent signal above the threshold intensity level; and
detecting the fluorescent signal to identify the aqueous droplets comprising the target nucleic acid molecule in one or more of the aqueous droplets.
12. The method of claim 11 , wherein the target nucleic acid molecule is selected from the group consisting of: a nucleic acid, a protein, an antibody, an aptamer, a cell, and a microorganism.
13. The method of claim 11 , wherein prior to the providing step, the method comprises forming the plurality of non-single-file aqueous droplets.
14. The method of claim 11 , wherein the plurality of non-single-file aqueous droplets are in an immiscible fluid.
15. The method of claim 14 , wherein the immiscible fluid is oil.
16. The method of claim 15 , wherein the oil comprises a surfactant.
17. The method of claim 16 , wherein the surfactant is a fluorosurfactant.
18. The method of claim 15 , wherein the oil is a fluorinated oil.
19. The method of claim 11 , wherein the plurality of the non-single-file aqueous droplets comprise no more than a single target nucleic acid molecule.
20. The method of claim 11 , wherein one or more aqueous droplets are empty.
21. The method of claim 11 , wherein the non-single-file aqueous droplets are uniform in size.
22. The method of claim 11 , wherein the non-single-file aqueous droplets are non-uniform in size.
23. The method of claim 11 , wherein the detector is set to detect fluorescent signals at a threshold above background intensity level.