Microfluidic chemostat

• US 9,340,765 B2
• Filed: 03/26/2013
• Issued: 05/17/2016
• Est. Priority Date: 01/16/2004
• Status: Expired due to Fees

• Current Assignee: California Institute of Technology
• Original Assignee: California Institute of Technology
• Inventors: Balagadde, Frederick, Hansen, Carl L., Kartalov, Emil, Quake, Stephen R.
• Primary Examiner(s): Ware, Debbie K
• Assistant Examiner(s): Srivastava, Kailash C
• Application Number:
  US13/850,988
• Publication Number:
  US 20140141497A1
• Time in Patent Office: 1,148 Days
• Field of Search: 435/259, 435/294, 435/306.1
• US Class Current: 1/1
• CPC Class Codes: B01L 2300/0861 Configuration of multiple channels and/or chambers in a single devices
• CPC Class Codes: B01L 2300/0877 Flow chambers
• CPC Class Codes: B01L 2300/10 Means to control humidity and/or other gases
• CPC Class Codes: B01L 2300/163 Biocompatibility
• CPC Class Codes: B01L 2400/0481 squeezing of channels or chambers
• CPC Class Codes: B01L 2400/0655 pinch valves
• CPC Class Codes: B01L 3/5027 by integrated microfluidic structures, i.e. dimensions of channels and chambers are such that surface tension forces are important, e.g. lab-on-a-chip B01L3/5023 takes precedence; micromixers B01F33/30; microreactors for synthesis B01J19/0093; microcapillary devices in general B81B1/00
• CPC Class Codes: B01L 3/502738 characterised by integrated valves microvalves F16K99/0001
• CPC Class Codes: C12M 23/16 Microfluidic devices; Capillary tubes integrated microfluidic structures B01L3/5027; microreactors B01J19/0093
• CPC Class Codes: C12M 23/34 Internal compartments or partitions
• CPC Class Codes: C12M 39/00 Means for cleaning the apparatus or avoiding unwanted deposits of microorganisms apparatus for cleaning laboratory receptacles or instruments B01L13/02; cleaning in general B08B
• CPC Class Codes: C12P 1/00 Preparation of compounds or compositions, not provided for in groups C12P3/00 - C12P39/00, by using microorganisms or enzymes
• CPC Class Codes: C12P 19/04 Polysaccharides, i.e. compounds containing more than five saccharide radicals attached to each other by glycosidic bonds

Abstract

A method to suppress biofilm formation in a growth chamber of a chemostat is described. The method includes the steps of adding a lysis agent to an isolated portion of the growth chamber, and reuniting the isolated portion with the rest of the growth chamber. The microfluidic chemostat includes a growth chamber having a plurality of compartments. Each of the compartments may be fluidly isolated from the rest of the growth chamber by one or more actuatable valves. The chemostat also included a nutrient supply-line to supply growth medium to the growth chamber, and an output port to remove fluids from the growth chamber.

Claims

1. A method of suppressing biofilm buildup in a growth chamber of a chemostat, the growth chamber having a first compartment and a second compartment, the method comprising:

removing biofilm-producing cells from the first compartment, wherein removing the biofilm-producing cells from the first compartment comprises;

closing a first actuatable valve to fluidly isolate the first compartment from the growth chamber;

flushing the first compartment with an agent, wherein when the first compartment is flushed with the agent, the biofilm-producing cells are removed from the first compartment, and wherein flushing the first compartment with the agent comprises supplying the first compartment with the agent and removing the agent from the first compartment; and

opening the first actuatable valve to reunite the first compartment with the second compartment;

performing a first mixing of contents of the growth chamber;

removing biofilm-producing cells from the second compartment, wherein removing the biofilm-producing cells from the second compartment comprises;

closing a second actuatable valve to fluidly isolate the second compartment from the first compartment;

flushing the second compartment with an agent, wherein when the second compartment is flushed with the agent, the biofilm-producing cells are removed from the second compartment, and wherein flushing the second compartment with the agent comprises supplying the second compartment with the agent and removing the agent from the second compartment;

opening the second actuatable valve to reunite the second compartment with the growth chamber; and

performing a second mixing of the contents of the growth chamber.

2. The method of claim 1, further comprising pausing for a time period before removing the biofilm-producing cells from the second compartment.

3. The method of claim 1, wherein removing the agent from the first compartment comprises flushing the compartment with a growth medium and wherein removing the agent from the second compartment comprises flushing the second compartment with the growth medium.

4. The method of claim 1, wherein supplying the first compartment with the agent comprises opening a first actuatable supply valve to supply the agent to the first compartment, and wherein supplying the second compartment with the agent comprises opening a second actuatable supply valve to supply the agent to the second compartment.

5. The method of claim 1, wherein the agent is a lysis agent.

6. The method of claim 1, wherein closing the first actuatable valve comprises pressurizing a first control channel, and wherein closing the second actuatable valve comprises pressurizing a second control channel.

7. The method of claim 1, wherein the first compartment is of equal volume to the second compartment.

8. The method of claim 1, wherein removing the biofilm-producing cells from the first compartment and removing the biofilm-producing cells from the second compartment are performed at the same time an experiment is performed in the chemostat.

9. A method of suppressing biofilm buildup in a plurality of individually addressable, equal-volume compartments of a chemostat comprising:

removing biofilm-producing cells from each of the plurality of compartments one at a time in sequence, wherein removing the biofilm-producing cells from a compartment comprises;

closing an actuatable valve associated with the compartment to fluidly isolate the compartment from a remainder of the plurality of compartments, wherein closing the actuatable valve comprises pressurizing a flow channel;

flushing the compartment with an agent, wherein when the compartment is flushed with the agent, the biofilm-producing cells are removed from the compartment, and wherein flushing the compartment with the agent comprises;

supplying the compartment with the agent by opening an actuatable supply valve;

removing the agent from the compartment by flushing the compartment with a growth medium;

opening the actuatable valve to reunite the compartment with the remainder of the plurality of compartments; and

performing a rotary mixing of a contents of the plurality of compartments for a time period before removing the biofilm-producing cells from a next one of the plurality of compartments, wherein performing the rotary mixing of the contents of the plurality of compartments results in distribution of the contents across each of the plurality of compartments.

10. The method of claim 9, wherein the agent is a lysis agent.

11. The method of claim 9, wherein removing the biofilm-producing cells is performed at the same time an experiment is performed in the chemostat.