Systems and methods related to continuous flow droplet reaction
Described herein are systems relating to a continuous-flow instrument that includes all necessary components for digital droplet quantification without the need to introduce key reagents or collect and transfer droplets between stages of instrument operation. Digital quantification can proceed without any additional fluid or consumable handling and without exposing fluids to risk of external contamination.
1. A method for detecting a biological sample, comprising:
(a) providing a source of an immiscible fluid, a first injector having a zero dead volume and a second injector having a zero dead volume, wherein surfaces of the first injector and the second injector are fluorophilic;
(b) directing (i) a first dispersed phase from said first injector to a coalescer, and (ii) a second dispersed phase from said second injector to said coalescer, to yield a fluid comprising said first dispersed phase separated from said second dispersed phase by said immiscible fluid from said source, wherein said first dispersed phase or said second dispersed phase comprises said biological sample;
(c) directing said fluid from said coalescer to a reactor downstream of said coalescer, which fluid comprises a third dispersed phase comprising said biological sample;
(d) in said reactor, subjecting said fluid to conditions sufficient to conduct a reaction on said biological sample; and
(e) using a detector to detect said biological sample or derivative thereof.
2. The method of claim 1 , wherein (b) comprises (i) using said immiscible fluid from said source to direct said first dispersed phase from said first injector to said coalescer, or (ii) using said immiscible fluid from said source to direct said second dispersed phase from said second injector to said coalescer.
3. The method of claim 1 , wherein said first injector and said second injector are part of a housing, and wherein (b) comprises moving said housing to separately bring said first injector and said second injector in fluid communication with said coalescer.
4. The method of claim 3 , wherein moving said housing comprises rotating said housing with respect to a rotational axis.
5. The method of claim 1 , wherein said coalescer combines said first dispersed phase and said second dispersed phase to yield said third dispersed phase comprising contents of said first dispersed phase and said second dispersed phase.
6. The method of claim 1 , wherein in (c) said third dispersed phase is said first dispersed phase or said second dispersed phase.
7. The method of claim 1 , wherein (c) comprises opening a restriction in a fluid flow path between said coalescer and said reactor.
8. The method of claim 1 , further comprising, subsequent to (b), using a stimulus source to apply a stimulus to said first dispersed phase or said second dispersed phase.
9. The method of claim 8 , wherein said stimulus is an electric field.
10. The method of claim 8 , wherein said stimulus distorts said first dispersed phase or said second dispersed phase.
11. The method of claim 10 , wherein said first dispersed phase or said second dispersed phase comprises a surfactant, and wherein said stimulus causes polarization of said surfactant in said first dispersed phase or said second dispersed phase.
12. The method of claim 10 , wherein said stimulus causes said first dispersed phase and said second dispersed phase to coalesce.
13. The method of claim 1 , wherein said detector is an optical detector, and wherein (e) comprises detecting an optical signal from said biological sample or derivative thereof.
14. The method of claim 1 , wherein said biological sample comprises a nucleic acid sample, wherein said third dispersed phase comprises nucleic acid extension reagents, wherein (d) comprises using said nucleic acid extension reagents to conduct said reaction on said nucleic acid sample to yield an extension product of said nucleic acid sample, and wherein (e) comprises using said detector to detect said extension product.
15. The method of claim 14 , wherein said reactor comprises a heat source, which heat source is used to increase a temperature of said third dispersed phase to conduct said reaction.
16. The method of claim 1 , wherein in (b), (i) said first dispersed phase is directed from said first injector to a first inlet of said coalescer and (ii) said second dispersed phase is directed from said second injector to a second inlet of said coalescer.
17. The method of claim 3 , wherein said housing comprises a metal, and wherein surfaces of the housing are lined or coated with fluorophilic material.