Device and Method for Generating Droplets

Abstract

Disclosed herein is a device (1) for generating a dispersion of a first phase in a second phase, the device comprising a first inlet (2) for supplying a first phase, which opens into a first chamber (4), a second inlet for supplying a second phase, opening into a second chamber and a dispersion outlet (6) for collecting the dispersion. Furthermore, the device comprises a membrane (7), which separates the first chamber (4) and the second chamber (5) and which comprises a first side (8) facing the first chamber (4) and a second side (9) facing the second chamber (5). The membrane (7) comprises multiple channels (10) extending from the first side (8) to the second side (9), providing a fluidic connection between the first chamber (4) and the second chamber (5). Each channel (10) comprises a channel inlet (11) arranged on the first side (8) mid a channel outlet 812) arranged on the second side (9). The first chamber (4) is typically configured such that a flow rate of the first phase through all of the individual channels (10) is essentially equal.

Claims

1. A device for generating a dispersion of a first phase in a second phase, comprising a first inlet configured to supply a first phase, the first inlet opening into a first chamber; a second inlet configured to supply a second phase, inlet opening into a second chamber; a dispersion outlet configured to collect the dispersion of the first phase in the second phase; a membrane separating the first chamber and the second chamber comprising a first side facing the first chamber and a second side facing the second chamber, wherein multiple channels extending from the first side to the second side of the membrane are configured to provide a fluidic connection between the first chamber and the second chamber, each channel comprising a channel inlet arranged on the first side of the membrane and a channel outlet arranged on the second side of the membrane; and wherein the first chamber is configured such that a flow rate of the first phase through each individual channel essentially uniform.

2. The device 4 )according to claim 1, wherein the first chamber is configured such that the pressure along the first side the membrane is essentially isobaric.

3. The device according to claim 1, wherein the first chamber has a rounded cross-section.

4. The device according to claim 3, wherein the first chamber has a hemispherical shape and the first inlet is arranged adjacent to a pole of the hemisphere-shaped first chamber.

5. The device according to claim 1, wherein the second side of the membrane has a total open area formed by the channels that is larger than a total open area of the first side of the membrane.

6. The device according to claim 1, wherein each channel comprises an end area at the channel outlet with a cross-sectional area which is larger than the cross-sectional area of the remaining part of the respective channel.

7. The device according to claim 1, wherein the first inlet is arranged in an angle of essentially 90° or less with respect to the channels of the membrane or the first inlet is essentially transversely arranged to the multiple channels of the membrane.

8. (canceled)

9. (canceled)

10. The device according to claim 1, further comprising a base wherein the first chamber partially formed by the base.

11. (canceled)

12. The device according to claim 1, wherein the first chamber comprises a gas outlet, and wherein the gas outlet and the membrane are arranged such that gas within the first chamber is directed towards the gas outlet and removed from the first chamber via the gas outlet when the first phase is supplied to the first chamber.

13. The device according to claim 1, wherein the device comprises at least one of a heater or cooler configured to heat or cool at least one of the first phase or the second phase.

14-16. (canceled)

17. The device according to claim 1, wherein the membrane comprises a tag, and wherein the device further comprises a read-out unit configured to retrieve data from the tag and a control unit configured to process the data from the tag.

18. (canceled)

19. The device according to claim 1, further comprising an analysis unit with a sensor configured to determine and control quality values including the size and size distribution of the generated monodisperse droplets.

20. A membrane for a device according to claim 1, comprising a first side and a second side opposite from the first side; and multiple channels extending from the first side to the second side through the membrane, wherein each channel comprises a channel inlet arranged at the first side, a channel outlet arranged at the second side, and a main section arranged between the channel inlet and the channel outlet, and wherein the channel outlet comprises a shape deviating from the shape of the main section.

21. The membrane according to claim 20, wherein a cross-sectional area of the channel outlet is larger than a cross-sectional area of the rest of the channel.

22. (canceled)

23. The membrane according to claim 20, wherein each channel of the membrane has a rounded cross-section with respect to a transversal plane.

24. (canceled)

25. The membrane according to claim 20, further comprising at least one solid support structure without channels dividing the membrane in two or more channel containing sections.

26. The membrane according to claim 20, wherein the membrane comprises a tag.

27. (canceled)

28. A method for generating a dispersion of a first phase in a second phase using a device according to claim 1, comprising supplying a first phase through the first inlet into the first chamber, and supplying a second phase through the second inlet into the second chamber, wherein the first phase flows from the first chamber through the multiple channels of the membrane into the second chamber to form a dispersion of the first phase in the second phase.

29. The method according to claim 28, wherein a pressure along the first side of the membrane is essentially isobaric.

30. The method according to claim 28, wherein the mass flow through each of the individual channels is essentially equal over the membrane.

31-33. (canceled)

34. The method according to claim 28, further comprising retrieving data by a read-out unit from a tag on the membrane and providing the retrieved data to a control unit which processes the data.

35. The method according to claim 28, further comprising transmitting data by a transmitting unit to a receiver.

36. (canceled)

37. The method according to claim 28, further comprising processing, the generated dispersion of the first phase in the second phase to generate capsules and particles, including at least one of microcapsules, micro-particles, nanocapsules, or nanoparticles.

38. A system for generating a dispersion with multiple core droplets comprising at least two devices according to claim 1, connected in series.

39. The device according to claim 1, wherein the second inlet comprises a supply channel being at least partially circumferentially arranged around a central longitudinal axis, the axis being perpendicular to the first and second side of the membrane and intersecting the center of the membrane.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0102] The herein described invention will be more fully understood from the detailed description given herein below and the accompanying drawings which should not be considered limiting to the invention described in the appended claims. The drawings show:

[0103] FIG. 1 a schematic view of a device for generating a dispersion of a first phase in a second phase according to a first embodiment of the invention;

[0104] FIG. 2 a cross-sectional view of the device shown in FIG. 1;

[0105] FIG. 3 an exploded partially cut-out view of the device shown in FIG. 1;

[0106] FIG. 4 a schematic view of a device 1′ according to another embodiment of the invention;

[0107] FIG. 5 a schematic enlarged view of a second side of a membrane according to a first embodiment of the invention;

[0108] FIG. 6 a partial cross-sectional view of the membrane shown in FIG. 5 along axis A-A;

[0109] FIG. 7a schematic partial representation of different channel outlet geometries according to other embodiments of the invention;

[0110] FIG. 8 a partial cross-sectional of a device according to another embodiment of the invention;

[0111] FIG. 9 a cross-sectional of a device according to another embodiment of the invention; and

[0112] FIG. 10 a schematic view of a membrane according to another embodiment of the invention.

DETAILED DESCRIPTION

[0113] FIG. 1 depicts device 1 for generating a dispersion of a first phase in a second phase. Device 1 comprises a container 19, which is made from glass and base 14 being made from metal. Base 14 comprises a first inlet (not shown, see FIG. 2) for supplying a first phase, opening into a first chamber. The first chamber is partly formed by base 14 and membrane 7 (see FIG. 2). Container 19 comprises second inlet 3 for supplying a second phase, opening into a second chamber and dispersion outlet 6 for collecting the dispersion generated within the second chamber. The second chamber is being formed by container 19 and membrane 7 (see FIG. 2). Device 1 further comprises membrane holding structure 20 being fixedly connected to base 14. Furthermore, the device contains container holding structure 21, which is fixedly connected via clamp device 18 to membrane holding structure 20. As a result, container 19 is fixedly connected to base 14.

[0114] FIG. 2 shows a cross-sectional view of device 1. Device 1 comprises base 14 with first inlet 2 for supplying a first phase. Inlet 2 opens into first chamber 4, which is partially formed by base 14. Device 1 further contains container 19 with second inlet 3 for supplying a second phase and dispersion outlet 6 for collecting the dispersion of the first phase in the second phase. Second inlet 30pens into second chamber 5, which is partially formed by container 19. The first chamber and the second chamber are being separated by membrane 7. As can be readily seen from FIG. 2, the first chamber has a rounded cross-section with respect to the corresponding cross-sectional plane along the central longitudinal axis 15 and being perpendicular to membrane 7. In the particular embodiment shown, first chamber 4 has a semi-circular cross-section and may thus have the shape of a hemisphere. First inlet 2 is arranged in the region of pole 13 of the hemisphere. Second chamber 5 is tapered towards dispersion outlet 6, which is arranged on longitudinal axis 15 extending along the longitudinal direction of the device, intersecting the center of the first and second chamber, being perpendicular to membrane 7 and intersecting the center of the membrane. As can be seen, longitudinal axis 15 constitutes a central axis of the device in the longitudinal direction. In the embodiment shown, the second chamber is arch-shaped towards dispersion outlet 6. Thus, second chamber 6 has a U-shaped cross-section. First inlet 2 is arranged in an angle α of essentially 90° with respect to central axis 15 and the channels of the membrane, which are in general parallel to axis 15. Device 1 comprises membrane holder 20 and container holder 21, which are fixedly connected with each other via releasable clamp device 18. Membrane 7 is mounted to membrane holder 20 by clamping the membrane between membrane holder 7 and base 14. Membrane holder 20 is fixedly connected to base 14 via clamp device 18. For safely securing glass container 19 between membrane holder 20 and container holder 21, pad 23, which in the particular case is a foam pad, can be arranged between container 19 and container holder 21. Membrane holder 20 comprises groove 22, for receiving container 19.

[0115] FIG. 3 shows an exploded view of partially cut device 1. As can be seen, the first chamber is partially formed by base 14 and has the shape of a hemisphere. First inlet 2, which is arranged in an angle of essentially 90° to central axis 15, is arranged on the pole of the hemisphere. Base 14 comprises spacer ring 16 which enables the use of different membranes with different thicknesses and membrane holder 20 comprises sealing ring 17. Membrane 7 is arranged between rings 16 and 17. The design of device 1 with adjustable clamp device 18 allows to employ membranes of various thicknesses. Membrane holder 20 further comprises circumferential groove 22 for receiving the lower end portion of container 19. Clamp device 18 fixedly and releasably connect membrane holder 20 with container holder 21.

[0116] FIG. 4 shows a schematic view of a device 1 according to a preferred embodiment of the invention. Second chamber 5 is formed by container 19 and membrane 7 which separates first chamber 4 from second chamber 5. Container 19 comprises dispersion outlet 6, which is in fluid connection with product vessel 29 and waste vessel 30. In general, the fluid flow may be controlled by a valve, such as a three-way valve. Device 1 further comprises first reservoir 24 which is in fluid communication with first chamber 4 for providing a first phase into first chamber 4 via first inlet 2. Arranged between first reservoir 24 and first inlet 2 is a flow meter for measuring the fluid flow of the first phase. First reservoir 24 is in fluid connection with pressure source 32. Furthermore, pressure regulator 27a is arranged between first reservoir 24 and pressure source 32. In addition to first reservoir 24, device 1 comprises rinsing reservoir 31 which is also in fluid communication with both first chamber 4 and pressure source 32. Rinsing reservoir 31 is configured for providing a rinsing solution into first chamber 4 for cleaning device 1 after its intended use.

[0117] In general, if a rinsing solution is provided to first chamber 4, the three-way valve arranged between product and waste vessel 29 and 30 and dispersion outlet 6 is configured such that the rinsing solution can flow into waste vessel 30. Device 1 further comprises heater 33 configured for heating the first and second chamber during the production of a dispersed phase. Furthermore, second chamber 5 is in fluid communication with second reservoir 25 for supplying second chamber 5 with the second phase. Flow restrictor 26 and flow meter 28 are arranged between second chamber 5 and second reservoir 25. In the embodiment shown, flow restrictor 26 is arranged behind flow meter 28 in the direction of flow. Second reservoir 25 is further in fluidic connection with pressure source 32. Additionally, a second pressure regulator 27b is arranged between second reservoir 25 and pressure regulator 27a. In a representative experiment, the first reservoir was pressurized with an overpressure of 0.08 atm and the second reservoir with an overpressure of 0.4 atm. A 1 L product vessel could be filled with the generated dispersion of the first phase in the second phase within only 12 min. Device 1 further comprises a read-out unit 39 configured for retrieving data from a tag of membrane 7 and a control unit 40 configured for processing the data from the tag. In general, the read-out unit may be arranged at any suitable position. For example, the user may scan the tag of the membrane before placing the membrane between the first chamber and the second chamber. Alternatively, the read-put unit and the tag may in general be arranged such that it can directly read out the tag when the membrane is positioned between the first chamber 4 and the second chamber 5. Device 1 additionally contains transmitter unit 41 configured for transmitting data to a receiver. In general, transmitter unit 41, control unit 40 and read-out unit 39 may be functionally connected. Device 1 also contains analysis unit 42 with a sensor for determining and controlling quality values, in particular the size and size distribution of the generated monodisperse droplets. Analysis unit 42 is positioned downstream of membrane 7, in this case downstream of dispersion outlet 6.

[0118] FIG. 5 shows a monolayer membrane 7 for generating a dispersion of a first phase in a second phase, which can be used in a device as described in any of the embodiments disclosed herein. Membrane 7 has a first side 8 (not shown) and second side g, which in an operative state faces a second chamber. Multiple microchannels extend through membrane 7. Each channel 10 has an elliptical contour. Membrane 7 further has a computer readable tag 43 attached to the second side 9. In addition, membrane 7 comprises membrane sealing ring 44, which circumferentially fully surrounds the periphery of the membrane. Membrane 7 can in some cases additionally comprise membrane storage unit 45 configured to receive and store data transmitted by a transmitter device.

[0119] FIG. 6 shows monolayer membrane 7 with thickness T of FIG. 5 in a cross-sectional view along A-A. The membrane comprises first side 8 and second side 9. Multiple channels 10 (drawn in exaggerated dimensions) each extend from first side 8 of the membrane to second side 9 of the membrane. Each channel comprises a channel inlet ii arranged at first side 8 and channel outlet 12 arranged at second side 9. Arranged between each channel inlet and channel outlet is main section M. As can be readily seen, second side 9 comprises a total open area that is larger than the total open area of first side 8. Furthermore, the shape of each channel outlet 12 is different from the shape of the rest of the channel, i.e. of main section M and channel inlet 11. The cross-sectional area of each channel outlet 12 is larger than the cross-sectional area of the rest of the corresponding channel 10. In the embodiment shown, channel outlet 12 is wedge-shaped.

[0120] FIG. 7 shows a cross-sectional schematic partial view of a selection of channels with differently shaped channel outlets. For example, FIG. 7a) shows a wedge-shaped channel outlet. FIG. 7b) shows an angular channel outlet. FIG. 7c) and 7d) show a channel outlet in which the channel walls are convexly (FIG. 7c) or concavely (FIG. 7d) curved. FIG. 7e) to 7g) show channels with a constriction, which is arranged adjacent the channel outlet and arranged between the respective channel outlet and the rest of the channel. As can be seen, all different channels shown have a channel outlet with a larger cross-sectional area than the cross-sectional area of the rest of the channel.

[0121] FIG. 8 shows a partial cross-sectional view of a device according to another embodiment of the invention. The device 1 has a first inlet 2 for supplying a first phase, which opens into first chamber 4 having a rounded cross-section. In the embodiment shown, first chamber 4 has the shape of a spherical dome with a radius at the base of the dome being smaller than the radius of the corresponding hypothetical full sphere. Second chamber 5 is at least partially defined by container 19. The device further comprises dispersion outlet 6 for collecting the generated dispersion of the first phase in the second phase. The corresponding membrane is not shown for better visualization. The second inlet opening towards the second chamber 5 comprises in the depicted embodiment a supply channel 34 being circumferentially arranged around central longitudinal axis 15 and/or the axis being perpendicular to the first and second side of the membrane and intersecting the center of the membrane. The supply channel 34 comprising a plurality of openings 35 into second chamber 5. Openings 35 are uniformly distributed along the circumference of the supply channel and are arranged in the direction of dispersion outlet 7. In the embodiment shown, supply channel 34 forms a ring-like structure, being arranged at the bottom of second chamber 5, i.e. at the edge of the membrane and container 19. In the embodiment shown, the supply channel has an angular cross-section. Alternatively, the supply channel may have a rounded, particularly a circular cross-section.

[0122] FIG. 9 shows a cross-sectional view of another embodiment of the device according to the invention. The device 1 has a first inlet 2 for supplying a first phase, which opens into first chamber 4 having a rounded cross-section. In the embodiment shown, first chamber 4 has the shape of a spherical dome. A membrane 7 separates first chamber 4 from second chamber 5. In contrast to the embodiment shown in FIG. 2, the membrane is inclined with respect to the central longitudinal axis 15 of the device 1. The acute angle 13 in a cross sectional view along the central longitudinal axis between the central longitudinal axis and the second side of the membrane is between 45° and 89°, preferably between 70° and 88°, more preferably between 78° and 87°. The device 1 comprises additionally gas outlet 36. The gas outlet and the membrane are arranged such that gas within the first chamber is during supplying the first phase to the first chamber, in particular during the first filling, directed towards the gas outlet and removed from first chamber 4 via the gas outlet 36. As can be seen, gas outlet 36 is arranged at the top edge of first chamber 4, which is formed by the membrane 7 and the chamber wall, which is part of the base 14. Before the initial filling of first chamber 4 with the first phase, gas, particularly air, is present in the first chamber.

[0123] Upon filling of first chamber 4 with the first phase, air is pushed out of gas outlet 36. Due to the arrangement of membrane 7 and gas outlet 36, essentially all gas can be removed from first chamber 4. As remaining gas, in particular gas bubbles have detrimental effects on pressure distribution, size and particle distribution becomes more uniform.

[0124] FIG. 10 depicts a membrane 7 according to another embodiment of the invention. Membrane 7 contains several intersecting solid support structures 37 devoid of channels, which divide the membrane in several triangularly shaped channel containing sections 3 8. Such a solid support structure can be integral with membrane 7 or can comprise additional elements, which are arranged on top of the first and/or second surface of the membrane.

TABLE-US-00001 LIST OF REFERENCE CHARACTERS  1 Device  2 First inlet  3 Second inlet  4 First chamber  5 Second chamber  6 Dispersion outlet  7 Membrane  8 First side  9 Second side 10 Channel 11 Channel inlet 12 Channel outlet 13 Pole 14 Base 15 Central axis 16 Spacer ring 17 Sealing ring 18 Clamp device 19 Container 20 Membrane holder 21 Container holder 22 Groove 23 Pad 24 First reservoir 25 Second reservoir 26 Flow restrictor 27 a, b Pressure regulators 28 Flow Meter 29 Product vessel 30 Waste vessel 31 Rinsing reservoir 32 Pressure source 33 Heater or cooler 34 Supply channel 35 Opening 36 Gas outlet 37 Solid support structure 38 Section 39 Read-out unit 40 Control unit 41 Transmitter unit 42 Analysis Unit 43 Tag 44 Membrane sealing ring 45 Membrane storage unit M Main section