Monodisperse microbubble and microdroplet generating device and method of using the same

Abstract

The present application relates to a monodisperse microbubble and microdroplet generating device and a method for using the same. The monodisperse microbubble and microdroplet generating device comprises a substrate and a cover plate covering the substrate. During use of the above-mentioned monodisperse microbubble and microdroplet generating device, the two-phase extrusion pressure between the continuous phase and the dispersed phase and the extrusion pressure at the corners with the dispersed phase make the size of the microbubbles (microdroplets) generated by the device of the present application smaller than the size of the microbubbles (microdroplets) generated by the T-shaped microfluidic device under the same conditions, thereby reducing the limitation of the channel (first strip groove, second strip groove, third strip groove) size on the size of the generated microbubbles (microdroplets), and can generate monodisperse microbubbles (microdroplets) with a size smaller than the channel width.

Description

Technical Field

[0001] The present application relates to the field of microfluidics, and in particular to a device for generating monodisperse microbubbles and microdroplets and a method for using the same. Background Art

[0002] Microbubbles and microdroplets (less than 100 microns in diameter) possess properties such as large specific surface area for mass transfer, making their continuous and controllable preparation crucial for chemical process intensification. Currently, the equipment used to prepare monodisperse microbubbles is primarily microfluidic devices with characteristic channel diameters on the order of hundreds of microns. With the rapid advancement of mechanical micromachining and 3D printing technologies, a variety of microfluidic devices have been proposed, including T-type microfluidics, Y-type microfluidics, focused flow microfluidics, coaxial flow microfluidics, and step emulsification microfluidics. Under fixed operating conditions for the dispersed and continuous phases, microbubbles (microdroplets) can be uniformly prepared with a narrow size distribution at a constant generation frequency due to scale and interface effects within the confined space of the microfluidic device.

[0003] T-type microfluidic devices are currently the most widely used microfluidic devices in industry due to their simple structure and ease of scaling up. Within a T-type microfluidic device, the continuous phase inlet channel is perpendicular to the dispersed phase inlet channel. The generation of microbubbles (microdroplets) is controlled by a squeezing mechanism, and their size gradually decreases with increasing continuous phase flow rate. Due to continuous phase seepage, the proportion of continuous phase flow that does not squeeze the microbubble (microdroplet) growth process also increases with increasing continuous phase flow rate. Therefore, the critical minimum microbubble (microdroplet) size required to maintain monodispersity is equal to the characteristic size of the microfluidic device's internal channels.

[0004] Although microbubbles (microdroplets) can be produced smaller than the characteristic dimensions of the internal channels of T-type microfluidic devices under extreme operating conditions, they exhibit a wide size distribution, resulting in uneven sizes of microbubbles (microdroplets) and low process controllability. Therefore, the controllable production of monodisperse microbubbles (microdroplets) smaller than the characteristic dimensions of the internal channels of T-type microfluidic devices remains a major technical challenge. Summary of the Invention

[0005] Based on this, it is necessary to provide a monodisperse microbubble and microdroplet generating device and its use method to address the problem that it is difficult to controllably produce monodisperse microbubbles (microdroplets) smaller than the characteristic size of its internal channel through a T-type microfluidic device.

[0006] A monodisperse microbubble and microdroplet generating device, comprising a substrate and a cover covering the substrate;

[0007] A first strip groove, a second strip groove, a third strip groove and a buffer groove are formed on a side of the substrate close to the cover plate; the first strip groove and the third strip groove extend in a first direction, and the second strip groove and the buffer groove extend in a second direction;

[0008] One end of the first strip groove, one end of the third strip groove, one end of the second strip groove and one end of the buffer groove converge and communicate to form a buffer zone;

[0009] The other end of the first strip-shaped groove passes through the side surface of the substrate and forms a first entrance;

[0010] The other end of the second strip-shaped groove passes through the side surface of the substrate and forms a second entrance;

[0011] The other end of the third strip groove passes through the side surface of the substrate and forms an outlet;

[0012] The other end of the buffer groove is spaced apart from the side surface of the substrate along the second direction;

[0013] The first direction, the second direction, and the thickness direction of the substrate are perpendicular to each other.

[0014] During actual use of the above-mentioned monodisperse microbubble and microdroplet generating device, a continuous phase fluid is injected into the second inlet, and the volumetric flow rate of the continuous phase fluid is adjusted to fill the buffer tank with the continuous phase fluid. A dispersed phase fluid is injected into the first inlet, and the volumetric flow rate of the dispersed phase fluid is adjusted. The dispersed phase fluid flows in a first direction within the first strip groove, and the continuous phase fluid flows in a second direction within the second strip groove. The dispersed phase fluid and the continuous phase fluid meet at the end of the buffer tank near the second strip groove, forming microdroplets or microbubbles. The continuous phase fluid then carries the microdroplets or microbubbles along the third strip groove to the outlet.

[0015] The reason why the size of the microbubbles (microdroplets) generated in the present application is small is that when the continuous phase fluid from the second inlet enters the buffer tank from the gap between the dispersed phase body and the cover plate, and the gap between the dispersed phase body and the base plate, and after the flow direction is reversed in the buffer tank, it impacts the dispersed phase body from the corner between the third strip groove and the buffer tank. At the same time, the dispersed phase body is squeezed by the dynamic fluid and collides with the corner between the third strip groove and the buffer tank, so that the microbubbles (microdroplets) separate from the dispersed phase body on the left side from the collision state. The microfluidic device separates and flows toward the outlet, while the T-shaped microfluidic device does not generate the above-mentioned multiple extrusion forces. Therefore, the above-mentioned two-phase extrusion force between the continuous phase and the dispersed phase and the extrusion force between the dispersed phase and the corner make the size of the microbubbles (microdroplets) produced by the device of the present application smaller than the size of the microbubbles (microdroplets) produced by the T-shaped microfluidic device under the same conditions. This reduces the limitation of the channel (first strip groove, second strip groove, third strip groove) size on the size of the generated microbubbles (microdroplets), and can produce microbubbles (microdroplets) smaller than the channel width. Moreover, the uniform size of the generated microbubbles (microdroplets) can be ensured by simply controlling the volume flow rate of the dispersed phase and the continuous phase. The size of the generated microbubbles (microdroplets) can be changed by changing the volume flow rate of the dispersed phase and the continuous phase.

[0016] In one embodiment, the substrate has a first side surface and a third side surface opposite to each other along a first direction, and a second side surface and a fourth side surface opposite to each other along a second direction;

[0017] The other end of the first strip-shaped groove passes through the first side surface and forms a first entrance;

[0018] The other end of the second strip-shaped groove passes through the second side surface and forms a second entrance;

[0019] The other end of the third strip-shaped groove passes through the third side surface and forms an outlet;

[0020] The other end of the buffer groove is spaced apart from the fourth side surface along the second direction.

[0021] In one embodiment, a sidewall of the buffer groove at one end facing away from the second strip-shaped groove is an arc surface.

[0022] In one embodiment, the first strip groove and the third strip groove have coaxial symmetry axes along the first direction;

[0023] The symmetry axes of the second strip-shaped groove and the buffer groove along the second direction are coaxial.

[0024] In one embodiment, the length and width of the substrate are the same as those of the cover plate, the length of the substrate is 6-8 cm, the width of the substrate is 3-4 cm, the thickness of the substrate is 8-10 mm, and the thickness of the cover plate is 2-3 mm.

[0025] In one embodiment, the cover plate is made of one of stainless steel, quartz glass, tempered glass, polymethyl methacrylate, and polytetrafluoroethylene;

[0026] The substrate is made of one of stainless steel, quartz glass, tempered glass, polymethyl methacrylate, and polytetrafluoroethylene.

[0027] In one embodiment, the cross-sections of the first strip groove, the second strip groove, the third strip groove, and the buffer groove along the thickness direction of the substrate are rectangular;

[0028] The second strip groove, the third strip groove and the buffer groove have the same depth.

[0029] In one embodiment, the ratio of the width to the depth of the first strip-shaped groove is in the range of 1:1-3:1;

[0030] The ratio of the width to the depth of the second strip groove is in the range of 1:1-3:1;

[0031] The ratio of the width to the depth of the third strip groove is in the range of 1:1-3:1;

[0032] The ratio of the width to the depth of the buffer groove is in the range of 1:1-3:1.

[0033] In one embodiment, the cover plate and the base plate are connected by heat pressing or sealed by fasteners.

[0034] One embodiment of the present application further provides a method for using a monodisperse microbubble and microdroplet generating device, for generating microdroplets or microbubbles using the monodisperse microbubble and microdroplet generating device. The method for using the monodisperse microbubble and microdroplet generating device comprises the following steps:

[0035] injecting a continuous phase fluid into the second inlet and adjusting the volume flow rate of the continuous phase fluid so that the buffer tank is filled with the continuous phase fluid;

[0036] injecting a dispersed phase fluid into the first inlet and adjusting the volume flow rate of the dispersed phase fluid;

[0037] The dispersed phase fluid and the continuous phase fluid meet at one end of the buffer tank close to the second strip-shaped groove and form microdroplets or microbubbles;

[0038] The dispersed phase fluid and the continuous phase fluid drive the micro-droplets or micro-bubbles along the third strip groove to flow to the outlet.

[0039] During actual use of the above-mentioned monodisperse microbubble and microdroplet generating device, a continuous phase fluid is injected into the second inlet, and the volumetric flow rate of the continuous phase fluid is adjusted to fill the buffer tank with the continuous phase fluid. A dispersed phase fluid is injected into the first inlet, and the volumetric flow rate of the dispersed phase fluid is adjusted. The dispersed phase fluid flows in a first direction within the first strip groove, and the continuous phase fluid flows in a second direction within the second strip groove. The dispersed phase fluid and the continuous phase fluid meet at the end of the buffer tank near the second strip groove, forming microdroplets or microbubbles. The continuous phase fluid then carries the microdroplets or microbubbles along the third strip groove to the outlet.

[0040] The reason why the size of the microbubbles (microdroplets) generated in the present application is small is that when the continuous phase fluid from the second inlet enters the buffer tank from the gap between the dispersed phase body and the cover plate, and the gap between the dispersed phase body and the base plate, and after the flow direction is reversed in the buffer tank, it impacts the dispersed phase body from the corner between the third strip groove and the buffer tank. At the same time, the dispersed phase body is squeezed by the dynamic fluid and collides with the corner between the third strip groove and the buffer tank, so that the microbubbles (microdroplets) separate from the dispersed phase body on the left side from the collision state. The microfluidic device separates and flows toward the outlet, while the T-shaped microfluidic device does not generate the above-mentioned multiple extrusion forces. Therefore, the above-mentioned two-phase extrusion force between the continuous phase and the dispersed phase and the extrusion force between the dispersed phase and the corner make the size of the microbubbles (microdroplets) produced by the device of the present application smaller than the size of the microbubbles (microdroplets) produced by the T-shaped microfluidic device under the same conditions. This reduces the limitation of the channel (first strip groove, second strip groove, third strip groove) size on the size of the generated microbubbles (microdroplets), and can produce microbubbles (microdroplets) smaller than the channel width. Moreover, the uniform size of the generated microbubbles (microdroplets) can be ensured by simply controlling the volume flow rate of the dispersed phase and the continuous phase. The size of the generated microbubbles (microdroplets) can be changed by changing the volume flow rate of the dispersed phase and the continuous phase. It was found that the smaller the size of the microbubbles (microdroplets) in the buffer tank, the smaller the microbubbles (microdroplets) produced by the device. This is because when the buffer tank is full of continuous phase, the buffering length of the continuous phase is the length of the entire buffer tank, making the flow direction of the continuous phase more stable. When the size of the microbubbles (microdroplets) in the buffer tank increases, the buffering distance of the buffer tank will be shortened accordingly, and the buffering flow direction of the continuous phase is affected by the microbubbles (microdroplets) in the buffer tank, so that the impact force of the continuous phase on the dispersed phase body in the buffer zone is absorbed by the microbubbles (microdroplets) in the buffer tank, thereby reducing the reverse impact force of the continuous phase on the dispersed phase body in the buffer zone. Therefore, the size of the microbubbles (microdroplets) produced by the device will increase. Therefore, in the above method, it is necessary to first introduce the continuous phase fluid so that the continuous phase fluid fills the buffer tank, so as to prevent the dispersed phase from entering the buffer tank to generate microbubbles (microdroplets) and forming a buffer dead zone, which will weaken the buffering effect. The order of introducing the above fluids further reduces the size of the microbubbles or microdroplets produced by the device. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 Schematic diagram of a device for generating monodisperse microbubbles and microdroplets according to an embodiment.

[0042] Figure 2 Comparison of transient graphs of microbubbles or microdroplets generated by a T-type microfluidic device and a monodisperse microbubble and microdroplet generation device.

[0043] Figure 3This is a transient diagram of the monodisperse microbubble and microdroplet generating device during the process of generating microbubbles or microdroplets.

[0044] Figure 4 Comparison of transient graphs during the microbubble (microdroplet) generation process when microbubbles (microdroplets) of different sizes are contained in the buffer tank of the monodisperse microbubble and microdroplet generation device.

[0045] Description of Figure Numbers:

[0046] 100-monodisperse microbubble and microdroplet generation device;

[0047] 110 - base plate; 111 - first strip groove; 112 - second strip groove; 113 - third strip groove; 114 - buffer groove; 115 - first inlet; 116 - second inlet; 117 - outlet; 118 - buffer zone;

[0048] 120-cover plate;

[0049] OX-first direction; OY-second direction. DETAILED DESCRIPTION

[0050] To make the above-mentioned objects, features, and advantages of the present application more clearly understood, the specific embodiments of the present application are described in detail below with reference to the accompanying drawings. The following description sets forth many specific details to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways than those described herein, and those skilled in the art can make similar improvements without violating the scope of the present application. Therefore, the present application is not limited to the specific embodiments disclosed below.

[0051] In the description of this application, it should be understood that if the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. appear, the orientation or position relationship indicated by these terms is based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing this application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this application.

[0052] In addition, if the terms "first" or "second" appear, these terms are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of technical features indicated. Therefore, a feature specified as "first" or "second" may explicitly or implicitly include at least one of such features. In the description of this application, if the term "plurality" appears, "plurality" means at least two, for example, two, three, etc., unless otherwise specifically defined.

[0053] In this application, unless otherwise specified or limited, the terms "mounted," "connected," "connected," "fixed," etc., should be interpreted broadly. For example, these terms may refer to fixed connections, removable connections, or integration; mechanical connections or electrical connections; direct connections or indirect connections through an intermediary; and internal communication between two components or interaction between two components, unless otherwise specified. Those skilled in the art will understand the specific meanings of these terms in this application based on the specific circumstances.

[0054] In this application, unless otherwise expressly specified or limited, if a first feature is described as being "above" or "below" a second feature, or similar descriptions, this may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Furthermore, when a first feature is described as being "above," "above," or "above" a second feature, it may mean that the first feature is directly above or diagonally above the second feature, or simply means that the first feature is at a higher level than the second feature. When a first feature is described as being "below," "below," or "below" a second feature, it may mean that the first feature is directly below or diagonally below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0055] It should be noted that if an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be an intermediate element. If an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be an intermediate element. If any, the terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used in this application are for illustrative purposes only and do not represent the only embodiment.

[0056] See Figure 1 , Figure 1 A structural schematic diagram of a monodisperse microbubble and microdroplet generating device 100 in one embodiment of the present application is shown. The monodisperse microbubble and microdroplet generating device 100 provided in one embodiment of the present application includes a substrate 110 and a cover plate 120 covering the substrate 110.

[0057] In the above-mentioned monodisperse microbubble and microdroplet generating device 100, a first strip groove 111, a second strip groove 112, a third strip groove 113, and a buffer groove 114 are provided on one side of the substrate 110 close to the cover plate 120. The first strip groove 111 and the third strip groove 113 extend in a first direction OX, while the second strip groove 112 and the buffer groove 114 extend in a second direction OY. One end of the first strip groove 111, one end of the second strip groove 112, one end of the third strip groove 113, and one end of the buffer groove 114 converge and connect to form a buffer zone 118. The other end of the first strip groove 111 passes through the side of the substrate 110 and forms a first inlet 115;

[0058] The other end of the second strip groove 112 passes through the side surface of the substrate 110 and forms a second inlet 116;

[0059] The other end of the third strip groove 113 passes through the side surface of the substrate 110 and forms an outlet 117;

[0060] The other end of the buffer groove 114 is spaced apart from the side surface of the substrate along the second direction OY;

[0061] During actual use of the monodisperse microbubble and microdroplet generating device 100, a continuous phase fluid is injected into the second inlet 116 and the volume flow rate of the continuous phase fluid is adjusted to fill the buffer tank 114 with the continuous phase fluid. A dispersed phase fluid is injected into the first inlet 115 and the volume flow rate of the dispersed phase fluid is adjusted. The dispersed phase fluid flows in the first strip groove 111 along the first direction OX, and the continuous phase fluid flows in the second strip groove 112 along the second direction OY. Figure 2 The dispersed phase fluid and the continuous phase fluid meet at the end of the buffer tank 114 near the second strip groove 112 and form micro droplets or micro bubbles. The continuous phase fluid carries the micro droplets or micro bubbles along the third strip groove 113 to the outlet 117.

[0062] Figure 2 The upper part is a transient diagram of the T-type microfluidic device generating microbubbles or microdroplets. Figure 2 The lower part shows a transient graph of microbubbles or microdroplets generated by the structure with the buffer tank 114 installed in this application. From left to right, the liquid flow rate increases from 2.0 ml / min to 3.0 ml / min. The gas flow rate and liquid flow rate in the upper and lower figures are the same. Comparing the two figures in each column, it can be seen that the size of the microbubbles (microdroplets) generated by the structure with the buffer tank 114 is smaller than that of the microbubbles (microdroplets) generated by the T-shaped microfluidic device. Figure 3 , Figure 3The monodisperse microbubble and microdroplet generating device 100 of the present application is captured by a high-speed camera during the process of generating microbubbles or microdroplets. The reason why the size of the microbubbles (microdroplets) generated in the present application is small is that when the continuous phase fluid from the second inlet 116 is Figure 2 The middle part enters the buffer groove 114 through the gap between the dispersed phase body and the cover plate 120 in the buffer zone 118, and the gap between the dispersed phase body and the substrate 110, and after the flow direction is reversed in the buffer groove, it impacts the dispersed phase body in the opposite direction from the corner between the third strip groove 113 and the buffer groove. At the same time, the dispersed phase body is squeezed by the dynamic fluid and collides with the corner between the third strip groove 113 and the buffer groove, so that the microbubbles (microdroplets) are separated from the dispersed phase body on the left side from the collision state and flow to the outlet. The T-type microfluidic device does not generate the above-mentioned multiple extrusion forces. Therefore, the above-mentioned two-phase extrusion force between the continuous phase and the dispersed phase and the extrusion force between the corner and the dispersed phase make the size of the microbubbles (microdroplets) generated by the device of the present application smaller than the size of the microbubbles (microdroplets) generated by the T-type microfluidic device under the same conditions, thereby reducing the limitation of the channel (first strip groove 111, second strip groove 112, third strip groove 113) size on the size of the generated microbubbles (microdroplets), that is, Figure 3 As shown, microbubbles (microdroplets) smaller than the channel width can be generated. By simply controlling the volume flow rates of the dispersed and continuous phases, the size of the generated microbubbles (microdroplets) can be guaranteed to be uniform. By varying the volume flow rates of the dispersed and continuous phases, the size of the generated microbubbles (microdroplets) can be varied.

[0063] See Figure 1 In one embodiment, the substrate 110 has a first side surface and a third side surface opposite to each other along a first direction OX, and a second side surface and a fourth side surface opposite to each other along a second direction OY. The other end of the first strip groove 111 passes through the first side surface and forms a first inlet 115. The other end of the second strip groove 112 passes through the second side surface and forms a second inlet 116. The other end of the third strip groove 113 passes through the third side surface and forms an outlet 117. The other end of the buffer groove 114 is spaced apart from the fourth side surface along the second direction OY. This makes the surface of the substrate rectangular, and each groove is flush with the side surface of the substrate 110, facilitating the injection of the dispersed phase and the continuous phase.

[0064] Specifically, the substrate 110 and the cover plate 120 may also be in other shapes, as long as they meet the structure of the four grooves in this application, which will not be described in detail here.

[0065] In one embodiment, the side wall of the buffer groove 114 at one end away from the second strip groove 112 is an arc surface, thereby guiding the continuous phase through the arc surface, so that the continuous phase flows along the arc surface to the corner between the third strip groove 113 and the buffer groove, thereby enhancing the buffering effect. If the buffer groove 114 is a rectangular parallelepiped as a whole, that is, the side wall of the buffer groove 114 at one end away from the second strip groove 112 is a plane, the impact from the continuous phase will directly hit the plane wall and then directly rebound to the dispersed phase at the mouth of the buffer groove 114. In the case of diversion, the flow direction of the continuous phase is unstable, thereby weakening the buffering effect.

[0066] Preferably, the sidewall of the buffer groove 114 at one end away from the second strip groove 112 is an arc surface, and the arc of the arc surface is 180 degrees, that is, a semicircular arc surface.

[0067] In one embodiment, the first strip grooves 111 and the third strip grooves 113 are coaxial along their axes of symmetry in the first direction OX. The second strip grooves 112 and the buffer grooves 114 are coaxial along their axes of symmetry in the second direction OY. This allows microbubbles (microdroplets) to move along the first direction OX without colliding with the sidewalls of the third strip grooves 113 or the sidewalls of the second strip grooves 112.

[0068] In one embodiment, the length and width of the substrate 110 and the cover plate 120 are the same, the length of the substrate 110 is 6-8 cm, the width of the substrate 110 is 3-4 cm, the thickness of the substrate 110 is 8-10 mm, and the thickness of the cover plate 120 is 2-3 mm, so that the cover plate 120 can completely and accurately cover the substrate 110 and can completely cover the first strip groove 111, the second strip groove 112, the third strip groove 113 and the buffer groove 114.

[0069] In one embodiment, the cover 120 is made of one of stainless steel, quartz glass, tempered glass, polymethyl methacrylate, and polytetrafluoroethylene. The substrate 110 is made of one of stainless steel, quartz glass, tempered glass, polymethyl methacrylate, and polytetrafluoroethylene.

[0070] Preferably, the cover plate 120 and the substrate 110 are made of the same material.

[0071] In one embodiment, the cover plate 120 and the base plate 110 are connected by heat pressing or sealed by fasteners, wherein the fasteners are screws or bolts.

[0072] In one embodiment, the cross-sections of the first strip groove 111 , the second strip groove 112 , the third strip groove 113 , and the buffer groove 114 along the thickness direction of the substrate 110 are rectangular.

[0073] The second strip groove 112, the third strip groove 113 and the buffer groove 114 have the same depth. Preferably, the first strip groove 111 and the third strip groove 113 form a strip groove extending along the first direction OX, and the width and depth of the openings are the same. The second strip groove 112 and the buffer groove 114 form a strip groove extending along the second direction OY, and the width and depth of the openings are the same. Figure 1 .

[0074] Preferably, the first strip groove 111 and the second strip groove 112 have the same length, so as to ensure that the volume flow rate when the dispersed phase and the continuous phase meet can be controlled.

[0075] In one embodiment, the ratio of the width to the depth of the first strip grooves 111 is in the range of 1:1-3:1. Specifically, the depth of the first strip grooves 111 is 100-300 μm, the width of the first strip grooves 111 is 100-300 μm, and the length of the first strip grooves 111 is 2-3 cm. The ratio of the width to the depth of the second strip grooves 112 is in the range of 1:1-3:1. Specifically, the depth of the second strip grooves 112 is 100-300 μm, the width of the second strip grooves 112 is 100-300 μm, and the length of the second strip grooves 112 is 2-3 cm.

[0076] The ratio of the width to the depth of the third strip groove 113 is in the range of 1:1-3:1. Specifically, the width of the third strip groove 113 is 100-300 μm, the depth of the third strip groove 113 is 100-300 μm, and the length of the third strip groove 113 is 4-5 cm.

[0077] The ratio of the width to the depth of the buffer groove 114 is in the range of 1:1-3:1, the length of the buffer groove 114 is 100-300 μm, the width of the buffer groove 114 is the same as the width of the second strip groove 112 , and the depth of the buffer groove 114 is the same as the depth of the second strip groove 112 .

[0078] One embodiment of the present application further provides a method for using the monodisperse microbubble and microdroplet generating device 100, which is used to generate microdroplets or microbubbles using the monodisperse microbubble and microdroplet generating device 100. The method for using the monodisperse microbubble and microdroplet generating device 100 comprises the following steps:

[0079] The continuous phase fluid is injected into the first inlet 115 and the volume flow rate of the continuous phase fluid is adjusted.

[0080] At the same time, the dispersed phase fluid is injected into the second inlet 116, and the volume flow rate of the dispersed phase fluid is adjusted.

[0081] The dispersed phase fluid and the continuous phase fluid meet at one end of the buffer tank 114 close to the second strip-shaped tank 112 and form micro-droplets or micro-bubbles.

[0082] The dispersed phase fluid and the continuous phase fluid drive the micro-droplets or micro-bubbles along the third strip grooves 113 to flow to the outlet 117 .

[0083] During actual use of the monodisperse microbubble and microdroplet generating device 100, a continuous phase fluid is injected into the second inlet 116 and the volume flow rate of the continuous phase fluid is adjusted to fill the buffer tank 114 with the continuous phase fluid. A dispersed phase fluid is injected into the first inlet 115 and the volume flow rate of the dispersed phase fluid is adjusted. The dispersed phase fluid flows in the first strip groove 111 along the first direction OX, and the continuous phase fluid flows in the second strip groove 112 along the second direction OY. Figure 2 The dispersed phase fluid and the continuous phase fluid meet at the end of the buffer tank 114 near the second strip groove 112 and form micro droplets or micro bubbles. The continuous phase fluid carries the micro droplets or micro bubbles along the third strip groove 113 to the outlet 117.

[0084] Figure 2 The upper part is a transient diagram of the T-type microfluidic device generating microbubbles or microdroplets. Figure 2 The lower part shows a transient graph of microbubbles or microdroplets generated by the structure with the buffer tank 114 installed in this application. From left to right, the liquid flow rate increases from 2.0 ml / min to 3.0 ml / min. The gas flow rate and liquid flow rate in the upper and lower figures are the same. Comparing the two figures in each column, it can be seen that the size of the microbubbles (microdroplets) generated by the structure with the buffer tank 114 is smaller than that of the microbubbles (microdroplets) generated by the T-shaped microfluidic device. Figure 3 , Figure 3 The monodisperse microbubble and microdroplet generating device 100 of the present application is captured by a high-speed camera during the process of generating microbubbles or microdroplets. The reason why the size of the microbubbles (microdroplets) generated in the present application is small is that when the continuous phase fluid from the second inlet 116 is Figure 2The middle part enters the buffer groove 114 through the gap between the dispersed phase body and the cover plate 120 in the buffer zone 118, and the gap between the dispersed phase body and the substrate 110, and after the flow direction is reversed in the buffer groove, it impacts the dispersed phase body in the opposite direction from the corner between the third strip groove 113 and the buffer groove. At the same time, the dispersed phase body is squeezed by the dynamic fluid and collides with the corner between the third strip groove 113 and the buffer groove, so that the microbubbles (microdroplets) are separated from the dispersed phase body on the left side from the collision state and flow to the outlet. The T-type microfluidic device does not generate the above-mentioned multiple extrusion forces. Therefore, the above-mentioned two-phase extrusion force between the continuous phase and the dispersed phase and the extrusion force between the corner and the dispersed phase make the size of the microbubbles (microdroplets) generated by the device of the present application smaller than the size of the microbubbles (microdroplets) generated by the T-type microfluidic device under the same conditions, thereby reducing the limitation of the channel (first strip groove 111, second strip groove 112, third strip groove 113) size on the size of the generated microbubbles (microdroplets), that is, Figure 3 As shown, microbubbles (microdroplets) smaller than the channel width can be generated. By simply controlling the volume flow rates of the dispersed and continuous phases, the size of the generated microbubbles (microdroplets) can be guaranteed to be uniform. By changing the volume flow rates of the dispersed and continuous phases, the size of the generated microbubbles (microdroplets) can be changed. Figure 4 It can be found that the smaller the size of the microbubbles (microdroplets) in the buffer tank, the smaller the microbubbles (microdroplets) produced by the device. This is because when the buffer tank is filled with the continuous phase, the buffer length of the continuous phase is the entire length of the buffer tank, making the flow direction of the continuous phase more stable. When the size of the microbubbles (microdroplets) in the buffer tank increases, the buffer distance of the buffer tank will be shortened, and the buffer flow direction of the continuous phase is affected by the microbubbles (microdroplets) in the buffer tank. The impact force of the continuous phase on the main dispersed phase in the buffer zone is absorbed by the microbubbles (microdroplets) in the buffer tank, thereby reducing the reverse impact force of the continuous phase on the main dispersed phase in the buffer zone. Therefore, the size of the microbubbles (microdroplets) produced by the device will increase. Therefore, in the above method, it is necessary to first introduce the continuous phase fluid so that the continuous phase fluid fills the buffer tank. This prevents the dispersed phase from entering the buffer tank to generate microbubbles (microdroplets) and form a buffer dead zone, which will weaken the buffering effect. The above fluid introduction order further reduces the size of the microbubbles or microdroplets produced by the device.

[0085] The following are examples corresponding to experiments with different parameters.

[0086] Specifically, deionized water, glycerol aqueous solution containing different glycerol mass fractions or n-hexadecane are used as the continuous phase fluid, and nitrogen or air is used as the dispersed phase fluid during the operation. Figure 1The monodisperse microbubble and microdroplet generating device 100 is shown for generating monodisperse microbubbles. Specifically, the dispersed phase fluid is delivered to the first strip groove 111 via a gas flow controller, the continuous phase fluid is delivered to the second strip groove 112 via a constant-flow syringe pump, and monodisperse microbubbles are generated in the buffer groove 114. The generated microbubbles flow out of the third strip groove 113. A high-speed camera is used to capture images of the microbubbles at the outlet 117 of the third strip groove 113, and the microbubble size is calculated.

[0087] Example 1:

[0088] The cover plate 120 and base plate 110 were made of polymethyl methacrylate. Deionized water was used as the continuous phase fluid, and air was used as the dispersed phase fluid. The continuous phase volume flow rate was 4.20 mL / min, and the dispersed phase volume flow rate was 1.30 mL / min. The first strip groove 111 had a width and depth of 100 μm, the second strip groove 112 had a width and depth of 100 μm, the buffer groove 114 had a width and depth of 100 μm, and a length of 100 μm. The third strip groove 113 had a width and depth of 100 μm. The measured microbubble diameter was 60.28 μm, and the coefficient of variation of the average bubble size was 0.13%.

[0089] Example 2:

[0090] Based on Example 1, a glycerol aqueous solution with a glycerol mass fraction of 60% was used as the continuous phase fluid. The diameter of the microbubbles was measured to be 51.75 μm, and the coefficient of variation of the average bubble size was 0.28%.

[0091] Example 3

[0092] Based on Example 1, n-hexadecane was used as the continuous phase fluid. The diameter of the microbubbles was measured to be 55.43 μm, and the coefficient of variation of the average bubble size was 0.17%.

[0093] Example 4:

[0094] Based on the first embodiment, polytetrafluoroethylene is used as the material of the cover plate 120 and the base plate 110. The diameter of the microbubbles is measured to be 59.45 μm, and the coefficient of variation of the average bubble diameter is 0.15%.

[0095] Embodiment 5:

[0096] Based on the first embodiment, stainless steel is used as the material of the cover plate 120 and the base plate 110. The diameter of the microbubbles is measured to be 58.79 μm, and the coefficient of variation of the average bubble diameter is 0.28%.

[0097] Example 6:

[0098] Based on the first embodiment, quartz glass is used as the material of the cover plate 120 and the substrate 110. The diameter of the microbubbles is measured to be 62.53 μm, and the coefficient of variation of the average bubble diameter is 0.10%.

[0099] Embodiment seven:

[0100] The cover plate 120 and base plate 110 were made of polytetrafluoroethylene. A 25% glycerol aqueous solution was used as the continuous phase fluid, and air was used as the dispersed phase fluid. The continuous phase flow rate was 3.80 mL / min, and the dispersed phase flow rate was 2.00 mL / min. The first strip groove 111 had a width and depth of 200 μm, the second strip groove 112 had a width and depth of 200 μm, the buffer groove 114 had a width and depth of 200 μm and a length of 100 μm, and the third strip groove 113 had a width and depth of 200 μm. The measured microbubble diameter was 80.79 μm, and the coefficient of variation of the average bubble diameter was 0.21%.

[0101] Embodiment 8:

[0102] Stainless steel was used as the material for the cover plate 120 and base plate 110. A 25% glycerol aqueous solution was used as the continuous phase fluid, and air was used as the dispersed phase fluid. The continuous phase volume flow rate was 8.00 mL / min, and the dispersed phase volume flow rate was 2.00 mL / min. The first strip groove 111 had a width and depth of 300 μm, the second strip groove 112 had a width and depth of 300 μm, the buffer groove 114 had a width and depth of 300 μm and a length of 200 μm, and the third strip groove 113 had a width and depth of 300 μm. The measured microbubble diameter was 93.65 μm, and the coefficient of variation of the average bubble diameter was 0.76%.

[0103] Embodiment 9:

[0104] Stainless steel was used as the material for the cover plate 120 and base plate 110. A glycerol aqueous solution with a 40% mass fraction of glycerol was used as the continuous phase fluid, and air was used as the dispersed phase fluid. The width and depth of the first strip groove 111 were both 150 μm, the width and depth of the second strip groove 112 were both 150 μm, the buffer groove 114 was both 150 μm wide and deep, and 100 μm long, and the width of the third strip groove 113 was 150 μm. The volume flow rate of the dispersed phase was 1.50 mL / min, and the volume flow rate of the continuous phase was 4.00 mL / min to 10.00 mL / min. The measured microbubble diameter decreased from 98.51 μm to 50.33 μm, and the coefficient of variation of the average bubble diameter was less than 2.00%.

[0105] Deionized water or glycerol aqueous solution containing different glycerol mass fractions was used as the continuous phase fluid, and n-hexane or n-octane was used as the dispersed phase fluid. Figure 1 The monodisperse microbubble and microdroplet generating device 100 is shown for producing monodisperse microdroplets. Specifically, the dispersed phase fluid is delivered to the first strip trough 111 via a constant-flow syringe pump, and the continuous phase fluid is delivered to the second strip trough 112 via a constant-flow syringe pump. Monodisperse microdroplets are generated in the buffer trough 114, and the produced microdroplets flow out of the third strip trough 113. A high-speed camera is used to capture images of the microdroplets at the outlet 117 of the third strip trough 113, and the droplet size is calculated.

[0106] Embodiment 10:

[0107] Polymethyl methacrylate was used as the material for the cover plate 120 and the base plate 110. Deionized water was used as the continuous phase fluid, and n-hexane was used as the dispersed phase fluid. The continuous phase volume flow rate was 4.20 mL / min, and the dispersed phase volume flow rate was 1.00 mL / min. The first strip groove 111 had a width and depth of 100 μm, the second strip groove 112 had a width and depth of 100 μm, the buffer groove 114 had a width and depth of 100 μm and a length of 100 μm, and the third strip groove 113 had a width and depth of 100 μm. The measured diameter of the microdroplets was 70.64 μm, and the coefficient of variation of the average droplet diameter was 0.18%.

[0108] Example 11:

[0109] Based on Example 10, a glycerol aqueous solution with a glycerol mass fraction of 50% was used as the continuous phase fluid. The diameter of the microdroplets was measured to be 62.83 μm, and the coefficient of variation of the average droplet diameter was 0.25%.

[0110] Example 12:

[0111] Based on the embodiment 10, stainless steel is used as the material of the cover plate 120 and the substrate 110. The diameter of the micro-droplets is measured to be 68.49 μm, and the coefficient of variation of the average droplet diameter is 0.21%.

[0112] Example 13:

[0113] Quartz glass was used as the material for the cover plate 120 and substrate 110. Deionized water was used as the continuous phase fluid, and n-octane was used as the dispersed phase fluid. The continuous phase volume flow rate was 2.10 mL / min, and the dispersed phase volume flow rate was 0.5 mL / min. The first strip groove 111 had a width of 100 μm and a depth of 50 μm. The second strip groove 112 had a width of 100 μm and a depth of 50 μm. The buffer groove 114 had a width of 100 μm, a depth of 50 μm, and a length of 500 μm. The third strip groove 113 had a width of 100 μm and a depth of 50 μm. The measured diameter of the microdroplets was 69.74 μm, and the coefficient of variation of the average droplet diameter was 0.43%.

[0114] Example 14:

[0115] Stainless steel was used as the material for the cover plate 120 and base plate 110. A glycerol aqueous solution with a 40% mass fraction of glycerol was used as the continuous phase fluid, and n-hexane was used as the dispersed phase fluid. The width and depth of the first strip groove 111 were both 200 μm, the width and depth of the second strip groove 112 were both 200 μm, the buffer groove 114 was both 200 μm wide and deep, and 100 μm long. The width and depth of the third strip groove 113 were both 200 μm. The volume flow rate of the dispersed phase was 0.50 mL / min, and the volume flow rate of the continuous phase was 3.00 mL / min to 8.00 mL / min. The measured microdroplet diameter decreased from 87.26 μm to 63.74 μm, and the coefficient of variation of the average droplet diameter was less than 1.00%.

[0116] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0117] The above-described embodiments merely represent several implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that a person of ordinary skill in the art may make various modifications and improvements without departing from the spirit of the present application, and these modifications and improvements fall within the scope of protection of the present application. Therefore, the scope of protection of the present patent application shall be determined by the appended claims.

Claims

1. A monodisperse microbubble and microdroplet generating device, characterized in that: The monodisperse microbubble and microdroplet generating device comprises a substrate and a cover plate covering the substrate; A first strip groove, a second strip groove, a third strip groove and a buffer groove are formed on a side of the substrate close to the cover plate; the first strip groove and the third strip groove extend in a first direction, and the second strip groove and the buffer groove extend in a second direction; One end of the first strip groove, one end of the third strip groove, one end of the second strip groove and one end of the buffer groove converge and communicate to form a buffer zone; The other end of the first strip-shaped groove passes through the side surface of the substrate and forms a first entrance; The other end of the second strip-shaped groove passes through the side surface of the substrate and forms a second entrance; The other end of the third strip groove passes through the side surface of the substrate and forms an outlet; The other end of the buffer groove is spaced apart from the side surface of the substrate along the second direction; The first direction, the second direction, and the thickness direction of the substrate are perpendicular to each other.

2. The monodisperse microbubble and microdroplet generating device according to claim 1, characterized in that: The substrate has a first side surface and a third side surface opposite to each other along a first direction, and a second side surface and a fourth side surface opposite to each other along a second direction; The other end of the first strip-shaped groove passes through the first side surface and forms a first entrance; The other end of the second strip-shaped groove passes through the second side surface and forms a second entrance; The other end of the third strip-shaped groove passes through the third side surface and forms an outlet; The other end of the buffer groove is spaced apart from the fourth side surface along the second direction.

3. The monodisperse microbubble and microdroplet generating device according to claim 1, characterized in that: A groove wall of the buffer groove at one end away from the second strip-shaped groove is an arc surface.

4. The monodisperse microbubble and microdroplet generating device according to claim 1, characterized in that: The symmetry axis of the first strip groove along the first direction and the symmetry axis of the third strip groove along the first direction are coaxial; A symmetry axis of the second strip-shaped groove along the second direction is coaxial with a symmetry axis of the buffer groove along the second direction.

5. The monodisperse microbubble and microdroplet generating device according to claim 1, characterized in that: The length and width of the substrate and the cover plate are the same, the length of the substrate is 6-8 cm, the width of the substrate is 3-4 cm, the thickness of the substrate is 8-10 mm, and the thickness of the cover plate is 2-3 mm.

6. The monodisperse microbubble and microdroplet generating device according to claim 1, characterized in that: The cover plate is made of one of stainless steel, quartz glass, tempered glass, polymethyl methacrylate, and polytetrafluoroethylene; The substrate is made of one of stainless steel, quartz glass, tempered glass, polymethyl methacrylate, and polytetrafluoroethylene.

7. The monodisperse microbubble and microdroplet generating device according to claim 1, characterized in that: The cross-sections of the first strip groove, the second strip groove, the third strip groove and the buffer groove along the thickness direction of the substrate are rectangular; The second strip groove, the third strip groove and the buffer groove have the same depth.

8. The monodisperse microbubble and microdroplet generating device according to claim 7, characterized in that: The ratio of the width to the depth of the first strip groove is in the range of 1:1-3:1; The ratio of the width to the depth of the second strip groove is in the range of 1:1-3:1; The ratio of the width to the depth of the third strip groove is in the range of 1:1-3:1; The ratio of the width to the depth of the buffer groove is in the range of 1:1-3:

1.

9. The monodisperse microbubble and microdroplet generating device according to claim 1, characterized in that: The cover plate and the base plate are connected by heat pressing or sealed by fasteners.

10. A method for using a monodisperse microbubble and microdroplet generating device, for generating microdroplets or microbubbles using the monodisperse microbubble and microdroplet generating device according to any one of claims 1 to 9, characterized in that: The method for using the monodisperse microbubble and microdroplet generating device comprises the following steps: injecting a continuous phase fluid into the second inlet and adjusting the volume flow rate of the continuous phase fluid so that the buffer tank is filled with the continuous phase fluid; injecting a dispersed phase fluid into the first inlet and adjusting the volume flow rate of the dispersed phase fluid; The dispersed phase fluid and the continuous phase fluid meet at one end of the buffer tank close to the second strip-shaped groove and form microdroplets or microbubbles; The continuous phase fluid drives the micro-droplets or micro-bubbles along the third strip groove to flow to the outlet.

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