Method of making a droplet-generating device

Patent metadata

Field	Value
Publication number	US-9403294-B2
Application number	US-201414255892-A
Country	US
Kind code	B2
Filing date	Apr 17, 2014
Priority date	Apr 17, 2013
Publication date	Aug 2, 2016
Grant date	Aug 2, 2016

Abstract

Method of making a droplet-generating device. In the method, a first droplet-generating device may be produced. The first droplet-generating device may include a molded portion created at least in part with a mold and also may include a plurality of droplet generators each formed at least in part by the molded portion. A set of droplets may be generated with each of one or more of the droplet generators. A property of at least one set of generated droplets may be determined. The mold may be modified based on the property. A second droplet-generating device may be produced that includes a molded portion created at least in part with the modified mold.

First claim

I claim:

1. A method of making a droplet-generating device, the method comprising:
producing a first droplet-generating device including a molded portion created at least in part with a mold and also including a plurality of droplet generators each formed at least in part by the molded portion;
generating a set of droplets with each of one or more of the droplet generators;
determining a property of at least one set of generated droplets;
modifying the mold based on the property; and
producing a second droplet-generating device including a molded portion created at least in part with the modified mold;
wherein the mold defines a projecting portion including a plurality of intersecting ridges that create a plurality of intersecting grooves in the molded portion, and wherein the step of modifying the mold includes a step of removing material from the projecting portion of the mold.

2. The method of claim 1 , wherein the step of determining a property includes a step of determining an average number of copies per droplet of a reference species in each set of generated droplets.

3. The method of claim 2 , wherein the reference species is a nucleic acid target, and wherein only a subset of the droplets in each set of generated droplets contain at least one copy of the nucleic acid target.

4. The method of claim 1 , wherein the property corresponds to a volume of individual droplets of the at least one set.

5. The method of claim 1 , wherein the step of generating a set of droplets includes a step of generating a plurality of emulsions with the plurality of droplet generators, with each emulsion containing portions of a same sample.

6. The method of claim 1 , wherein the step of producing a first droplet-generating device includes a step of attaching a sealing member to a surface of the molded portion of the first droplet-generating device to form circumferentially-bounded channels from the plurality of intersecting grooves.

7. The method of claim 1 , wherein the step of generating a set of droplets includes a step of generating a distinct set of droplets with each of two or more of the droplet generators, and wherein the step of determining a property includes a step of determining a property of each set of droplets generated.

8. The method of claim 1 , wherein the step of determining a property includes a step of determining a property of a distinct set of droplets generated by each of the plurality of droplet generators.

9. The method of claim 1 , wherein the first droplet-generating device has a first plurality of droplet generators, wherein the second droplet-generating device has a second plurality of droplet generators arranged in one-to-one correspondence with the first plurality of droplet generators, and wherein the step of modifying the mold causes the second plurality of droplet generators to be configured to generate a more uniform size of droplet than the first plurality of droplet generators.

10. The method of claim 1 , wherein the first droplet-generating device has a first plurality of droplet generators, wherein the second droplet-generating device has a second plurality of droplet generators arranged in one-to-one correspondence with the first plurality of droplet generators, and wherein the step of modifying the mold causes at least one droplet generator of the second plurality to be configured to generate a smaller size of droplet than a corresponding droplet generator of the first plurality.

11. The method of claim 1 , further comprising (a) generating a set of droplets with each of one or more droplet generators of the second droplet-generating device and (b) determining a property of least one set of droplets generated with the second droplet-generating device.

12. The method of claim 11 , further comprising a step of modifying the modified mold if the property of least one set of droplets generated with the second droplet-generating device is outside a tolerance.

13. The method of claim 1 , wherein the projecting portion includes a junction region having a junction where two or more of the ridges meet one another, and wherein the step of removing material includes a step of decreasing a height of the junction region at one or more positions of the junction region.

14. The method of claim 1 , wherein the step of modifying the mold includes a step of changing a dimension of a region of the projecting portion by less than one micrometer.

15. The method of claim 1 , wherein the step of removing material is performed at least in part with a beam of radiation.

16. The method of claim 15 , wherein the step of removing material is performed by removal of material from the mold with a laser.

17. A method of making a droplet-generating device, the method comprising:
producing a first droplet-generating device including a molded portion created at least in part with a mold and defining a plurality of grooves and also including a plurality of droplet generators each formed in part by an intersection of three or more of the plurality of grooves;
generating a set of droplets with each droplet generator;
determining an average number of copies per droplet of a nucleic acid target in each set of generated droplets;
modifying the mold based on the average number of copies determined for one or more of the sets of generated droplets; and
producing a second droplet-generating device including a molded portion created at least in part with the modified mold.

18. A method of making a droplet-generating device, the method comprising:
producing a first droplet-generating device including a molded portion created at least in part with a mold and also including a plurality of droplet generators each formed at least in part by the molded portion;
generating a set of droplets with each of one or more of the droplet generators;
determining a property of at least one set of generated droplets;
modifying the mold based on the property; and
producing a second droplet-generating device including a molded portion created at least in part with the modified mold;
wherein the molded portion of the first droplet-generating device includes a surface and a plurality of grooves formed in the surface, wherein each of the plurality of droplet generators includes a channel intersection at which grooves of the plurality of grooves meet one another.

19. The method of claim 18 , wherein the step of producing a first droplet-generating device includes a step of attaching a sealing member to the surface of the molded portion of the first droplet-generating device to form circumferentially-bounded channels from the plurality of grooves.

20. A method of making a droplet-generating device, the method comprising:
producing a first droplet-generating device including a molded portion created at least in part with a mold and also including a plurality of droplet generators each formed at least in part by the molded portion;
generating a set of droplets with each of one or more of the droplet generators;
determining a property of at least one set of generated droplets;
modifying the mold based on the property; and
producing a second droplet-generating device including a molded portion created at least in part with the modified mold;
wherein the first droplet-generating device has a first plurality of droplet generators, wherein the second droplet-generating device has a second plurality of droplet generators arranged in one-to-one correspondence with the first plurality of droplet generators, and wherein the step of modifying the mold

Assignees

• Bio Rad Laboratories Inc

Inventors

• Cauley Iii Thomas H

Classifications

• Y10T29/49764

  with testing or indicating · CPC title

• B01L2200/0673

  Handling of plugs of fluid surrounded by immiscible fluid · CPC title

• Y10T29/49982

  Coating · CPC title

• B01L2300/0816

  Cards, e.g. flat sample carriers usually with flow in two horizontal directions · CPC title

• Y10T29/49771

  Quantitative measuring or gauging · CPC title