Method for generating and retaining emulsions in a microfluidic chip

Abstract

To easily and stably generate an emulsion in a micro-channel chip.SOLUTION: There is provided a method for supplying a dispersed phase liquid and a continuous phase liquid to a micro-channel chip 10 to generate an emulsion, and the method includes: supplying the dispersed phase liquid to dispersed phase liquid holding units 102, 103; supplying the continuous phase liquid to a continuous phase liquid holding unit 101; and with the application of negative pressure to an exhaust port 150, in an emulsion forming unit 120, generating an emulsion including droplets formed of the dispersed phase liquid and a continuous phase formed of the continuous phase liquid, and conveying the emulsion generated in this manner to an emulsion channel 130. Before the supply of the dispersed phase liquid, continuous phase liquid channels 112, 113 filled with gas, the emulsion forming unit 120, and dispersed phase liquid channels 114, 115 are filled with a preliminary filling liquid. The preliminary filling liquid is the continuous phase liquid or a continuous phase liquid miscible liquid that is miscible with the continuous phase liquid.SELECTED DRAWING: Figure 1

Claims

1. A method for generating an emulsion by supplying a dispersed phase liquid and a continuous phase liquid to a microfluidic chip, The microfluidic chip has a dispersed phase liquid holding section, a dispersed phase liquid channel, a continuous phase liquid holding section, a continuous phase liquid channel, an emulsion forming section, an emulsion channel, and an outlet. The dispersed phase liquid holding section is connected to the emulsion forming section via the dispersed phase liquid flow path. The continuous phase liquid holding section is connected to the emulsion forming section via the continuous phase liquid flow path. The emulsion flow path is connected to the outlet, To supply the dispersed phase liquid to the dispersed phase liquid holding unit, The continuous phase liquid is supplied to the continuous phase liquid holding section, and By applying negative pressure to the outlet, the emulsion forming section generates an emulsion containing droplets composed of the dispersed phase liquid and a continuous phase composed of the continuous phase liquid, and the emulsion thus generated is transported to the emulsion flow path. Includes, Prior to supplying the dispersed phase liquid, the continuous phase liquid channel, the emulsion forming section, and the dispersed phase liquid channel, which are filled with gas, are filled with a pre-filling liquid, and The pre-filling liquid is the continuous phase liquid, or a continuous phase miscible liquid that is miscible with respect to the continuous phase liquid. It is characterized by, The aforementioned pre-filling liquid is the continuous phase liquid, After supplying the dispersed phase liquid to the dispersed phase liquid holding unit and before applying the negative pressure, a first portion of the continuous phase liquid for generating the emulsion is supplied to the continuous phase liquid holding unit. Here, the amount of the first portion of the continuous phase liquid is limited to a certain amount or less, thereby preventing the continuous phase liquid from entering the dispersed phase liquid channel, or ensuring that the amount of continuous phase liquid entering the dispersed phase liquid channel is a certain amount or less. method.

2. The method according to claim 1, wherein the negative pressure is applied during a predetermined time elapsed after the supply of the first portion of the continuous phase liquid, thereby suppressing or preventing the entry of the continuous phase liquid into the dispersed phase liquid channel.

3. The method according to claim 1, wherein, after applying the negative pressure, a second portion of the continuous phase liquid is further supplied to the continuous phase liquid holding unit.

4. A method for generating an emulsion by supplying a dispersed phase liquid and a continuous phase liquid to a microfluidic chip, The microfluidic chip has a dispersed phase liquid holding section, a dispersed phase liquid channel, a continuous phase liquid holding section, a continuous phase liquid channel, an emulsion forming section, an emulsion channel, and an outlet. The dispersed phase liquid holding section is connected to the emulsion forming section via the dispersed phase liquid flow path. The continuous phase liquid holding section is connected to the emulsion forming section via the continuous phase liquid flow path. The emulsion flow path is connected to the outlet, To supply the dispersed phase liquid to the dispersed phase liquid holding unit, The continuous phase liquid is supplied to the continuous phase liquid holding section, and By applying negative pressure to the outlet, the emulsion forming section generates an emulsion containing droplets composed of the dispersed phase liquid and a continuous phase composed of the continuous phase liquid, and the emulsion thus generated is transported to the emulsion flow path. Includes, Prior to supplying the dispersed phase liquid, the continuous phase liquid channel, the emulsion forming section, and the dispersed phase liquid channel, which are filled with gas, are filled with a pre-filling liquid, and The pre-filling liquid is the continuous phase liquid, or a continuous phase miscible liquid that is miscible with respect to the continuous phase liquid. It is characterized by, The aforementioned pre-filling liquid is the continuous phase liquid miscible liquid, After supplying the dispersed phase liquid to the dispersed phase liquid holding unit and before applying the negative pressure, the continuous phase liquid is supplied to the continuous phase liquid holding unit. Here, the amount of the continuous phase liquid is limited to a certain amount or less, thereby preventing the continuous phase liquid from entering the dispersed phase liquid channel, or ensuring that the amount of continuous phase liquid entering the dispersed phase liquid channel is a certain amount or less. method.

5. The method according to claim 4, wherein the negative pressure is applied during a predetermined time after the supply of the continuous phase liquid, thereby suppressing or preventing the entry of the continuous phase liquid into the dispersed phase liquid channel.

6. The method according to claim 4, wherein, after supplying the continuous phase liquid and applying the negative pressure, additional continuous phase liquid is further supplied to the continuous phase liquid holding unit.

7. The method according to claim 4, wherein the miscible liquid of the continuous phase has the same main component as the main component constituting the continuous phase.

8. The continuous phase liquid contains a surfactant, The continuous phase miscible liquid has a lower surfactant content than the continuous phase liquid. The method according to claim 4.

9. The method according to claim 8, wherein the miscible liquid of the continuous phase liquid has the same composition as the continuous phase liquid except that it contains a different amount of surfactant.

10. The method according to claim 1 or 4, wherein the continuous phase liquid mainly consists of a fluorine-based dispersion medium.

11. The dispersed phase liquid holding section includes a first dispersed phase liquid holding section and a second dispersed phase liquid holding section. The dispersed phase liquid channel includes a first dispersed phase liquid channel connected to the first dispersed phase liquid holding section, a second dispersed phase liquid channel connected to the second dispersed phase liquid holding section, and a dispersed phase liquid confluence section. The first dispersed phase liquid channel and the second dispersed phase liquid channel are each connected to the emulsion forming section via a dispersed phase liquid merging section. The method according to claim 1 or 4.

12. The microfluidic chip further has an emulsion-holding channel, The emulsion forming section is connected to the emulsion holding channel via the emulsion channel, The emulsion holding channel is connected to the discharge port, The method described above is To supply the dispersed phase liquid to the dispersed phase liquid holding unit, The continuous phase liquid is supplied to the continuous phase liquid holding section, and By applying negative pressure to the outlet, the emulsion forming section generates an emulsion containing droplets composed of the dispersed phase liquid and a continuous phase composed of the continuous phase liquid, and the emulsion thus generated is transported via the emulsion flow path to the emulsion holding flow path which is filled with gas. including, The method according to claim 1 or 4.

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