KR102022202B1 - Micro-fluidic device discharging bubble - Google Patents

Abstract

The present invention relates to a bubble discharge microfluidic device, wherein the bubble discharge microfluidic device according to the present invention is formed in a substrate as a flow path for moving a liquid sample and a through hole connecting the side surface of the substrate to the flow path. It characterized in that it comprises a vent for discharging the bubble to the outside.

Description

Bubble discharge microfluidic device {MICRO-FLUIDIC DEVICE DISCHARGING BUBBLE}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to microfluidic devices, and more particularly, to fluids in micro or nano-sized microchannels such as biochips, diagnostic devices, lab on a chip, or MEMS devices. The present invention relates to a microfluidic device in which a function of causing the flow is required.

Recently developed biochips, diagnostic devices, lab on a chip or MEMS (Micro Electro Mechanical Systems) devices have micro- or nano-sized microchannels that allow fluid samples to flow. Is formed.

When using the microfluidic device having such a microchannel, bubbles, vacuoles, or fine particles may be generated in the preparation of the sample, the supply of the sample, or the flow of the sample inside the device. At this time, the phenomenon in which the microchannels are clogged frequently due to such bubbles, vacuoles, or fine particle impurities occurs frequently. As such, when a microchannel is blocked, a serious problem may occur in which a device to which the microchannel is applied does not operate normally or its function is degraded.

Therefore, in order to stably maintain the performance of the device concerned, it is necessary to solve the phenomenon in which the microchannels are blocked by bubbles, vacuoles, or fine particles.

Patent Publication 10-2010-0020394

Accordingly, an object of the present invention is to solve such a conventional problem, by pre-filtering or removing the bubbles, vacuoles and fine particles that can block the main channel before reaching the main channel by the filtered material The present invention provides a microfluidic device capable of preventing a main channel from being blocked.

Problems to be solved by the present invention are not limited to the above-mentioned problems, and other problems not mentioned will be clearly understood by those skilled in the art from the following description.

According to the present invention, the object is a bypass flow path formed in the substrate, the bypass flow path in the form of a diagonal line in which the moving direction is repeatedly changed from side to side; And a filtration flow path formed in a partition wall between neighboring flow paths flowing in different directions from the bypass flow path, and filtering a flow path for filtering any one or more of bubbles, vacuoles, and fine particles among samples supplied to the bypass flow path. It can be achieved by a fluid element.

In addition, the above object is, according to the present invention, the bypass flow path which is formed in the substrate, the flow path in the form of a diagonal line in which the moving direction is changed repeatedly from side to side; And a partition wall is formed between neighboring flow paths flowing in different directions in the bypass flow path, and the partition wall is a fine gap formed to be spaced apart from an upper portion of the bubbles, vacuoles, and fine particles in the sample supplied to the bypass flow path. It can be achieved by a microfluidic device comprising a filtration flow path for filtering any one or more.

Here, the size of the filtration flow path is preferably smaller than the size of the bypass flow path.

Here, the substrate may include a first substrate on which a partition wall forming the bypass flow path and the filtering flow path is formed, and a second substrate covering the first substrate.

The vent hole may further include a vent part configured to discharge the bubble to the outside as a through hole connecting the side surface of the substrate and the bypass flow path.

Here, the partition wall may be formed of a plurality of micro cylinders spaced apart from each other, and the filtering flow path may be formed between the gaps between the neighboring micro cylinders.

Here, the filtration flow path may be formed of a plurality of minute gaps formed in the partition wall, and a collecting part, which is a space for collecting the material to be filtered, may be formed at an inlet of the filtration flow path.

Here, the filtration channel may be formed of a plurality of minute gaps formed in the partition wall, and the minute gaps may be formed such that the cross-sectional area gradually decreases along the path through which the sample flows to collect the filtered material.

Here, the inlet through which the sample is introduced to the substrate; A micro- or nano-sized main channel flowing through the sample; And an outlet through which the sample is discharged, and a bypass passage including the filtration passage may be formed between the inlet and the main channel.

In addition, the above object, according to the present invention, the flow path formed on the substrate to move the liquid sample; And a vent part for discharging the bubbles to the outside as a through hole connecting the side surface of the substrate and the flow path.

Here, the flow path may be an oblique flow path in which the moving direction is repeatedly changed from side to side.

Here, a plurality of nano pillars may be formed in the through hole.

The negative pressure forming unit may further include a negative pressure forming unit configured to form a negative pressure on a side surface of the substrate on which the vent unit is formed.

According to the present invention as described above has the advantage that it is possible to prevent the phenomenon of clogging the main channel by pre-filtering the bubbles, vesicles or fine particles contained in the sample before reaching the main channel.

In addition, by forming a plurality of filtering flow paths in the partition wall forming the bypass flow path, a large amount of material can be filtered along the path of the bypass flow path.

In addition, in the forming process of the microfluidic device including the main channel, by simultaneously implementing a filtration unit for filtering the bubbles, bubbles or fine particles contained in the sample, it is also possible to efficiently remove the bubbles without additional parts or processes have.

1 is a view schematically showing a microfluidic device according to an embodiment of the present invention.
FIG. 2 is an enlarged view of a portion of the filtration unit of FIG. 1 and illustrates an embodiment of a partition wall forming a filtration flow path.
3 is a view showing another embodiment of a partition wall forming a filtration flow path.
4 is a view showing another embodiment of a partition wall forming a filtration flow path.
5 is a cross-sectional view taken along AA of FIG. 1 according to an exemplary embodiment of the present invention.
6 is a cross-sectional view taken along AA of FIG. 1 according to another exemplary embodiment of the present invention.
7 is a view of the vent as part of the side view of FIG.
8 is a view illustrating another embodiment of the vent unit as part of the side view of FIG. 1.
FIG. 9 is a diagram illustrating a sample flow in a filtration unit in the embodiment of FIG. 3.
FIG. 10 is a diagram illustrating a flow of a sample in the filtration unit in the embodiment of FIG. 4.

Details of the embodiments are included in the detailed description and drawings.

Advantages and features of the present invention and methods for achieving them will be apparent with reference to the embodiments described below in detail with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but can be implemented in various different forms, and only the embodiments make the disclosure of the present invention complete, and the general knowledge in the art to which the present invention belongs. It is provided to fully inform the person having the scope of the invention, which is defined only by the scope of the claims. Like reference numerals refer to like elements throughout.

Hereinafter, the present invention will be described with reference to the drawings for describing the microfluidic device according to embodiments of the present invention.

FIG. 1 is a view schematically showing a microfluidic device according to an embodiment of the present invention, and FIG. 2 is an enlarged view of a portion of the filtration unit of FIG. 1, showing an embodiment of a partition wall forming a filtration channel. 3 is a view showing another embodiment of a partition wall forming a filtration flow path, FIG. 4 is a view showing another embodiment of a partition wall forming a filtration flow path, and FIG. 5 is a view of the present invention. 1 is a cross-sectional view taken along AA of FIG. 1, and FIG. 6 is a cross-sectional view taken along AA of FIG. 1, according to another exemplary embodiment. FIG. 8 is a view illustrating a vent part as a part of the side view of FIG. 8, and FIG. 8 is a view illustrating another exemplary embodiment of the vent part as a part of the side view of FIG. 1.

The microfluidic device 100 according to an embodiment of the present invention combines biomolecules such as DNA and protein on a small substrate to analyze gene defects, protein distribution, reaction patterns, and the like. , A micro- or nano-sized channel, mixer, pump, and valve function structure integrated on a single chip to enable high-speed, high-efficiency experiments or analyzes with very small amounts of samples Some or all of the chips (lab on a chip), micro electro mechanical systems (MEMS) devices that require flow control using micro flow paths, or diagnostic devices that perform component separation and analysis of very small amounts of biological fluids such as blood A microchannel through which a sample in a fluid state flows to the constituent element 100 is formed on the substrate 110.

The substrate 110 may be made of plastic, glass, or the like, but is not limited thereto. On the substrate 110, an inlet 120 through which a sample in a fluid state flows in and a main channel 140 through which the sample passes and an outlet 150 through which the sample passed through the main channel 140 are discharged to the outside may be formed. Can be.

As shown in FIG. 1, the main channel 140 may be formed to repeatedly change the moving direction from side to side in the form of an oblique line with a fine channel of nano or micro size.

In the microfluidic device 100 according to the present invention, a filtration unit 130 may be formed between the inlet 120 and the main channel 140. As described above, the sample introduced through the inlet 120 may include or generate bubbles, vacuoles, or impurities in the form of fine particles 200. Such bubbles, vacuoles, or fine particle-like impurities 200 may prevent the flow of the sample when the sample in the fluid state flows in the main channel 140. Therefore, in the present invention, the filter 130 is formed at the front end of the main channel 140 to filter fine bubbles, vacuoles, or fine particles such as impurities 200 to block the inflow into the main channel 140. By doing so, it is possible to solve the problem that the flow of the sample in the main channel 140 is blocked.

In this embodiment, the fluid particle device 100 having the filtration unit 130 formed between the inlet 120 and the main channel 140 will be described, but by forming a fluid particle device consisting only of the fruit portion 130, It can also be connected to the device separately.

The filter unit 130 is formed of a fine channel 132 connecting between the inlet 120 and the main channel 140, and preferably the direction of movement of the sample is repeatedly changed from side to side as shown in FIG. It may be formed as a fine channel 132 in the form of a diagonal line. As the movement direction of the sample is repeatedly changed from side to side, the partition wall 133 may be formed between the channels 132 through which the sample flows in neighboring different directions. As illustrated in FIG. 1, as the partition walls 133 extending from the left and right sides of the substrate 110 are alternately formed, diagonal channels 132 having a moving direction repeatedly changed from side to side may be formed. Hereinafter, the channel 132 formed by the partition wall 133 will be referred to as a bypass flow path 132.

Here, the left and right directions are for convenience of description and refer to the left and right sides when the direction connecting the inlet port 120 and the outlet port 150 is defined up and down as shown.

At this time, in the present invention, a plurality of filtration flow paths 134 may be formed in the partition wall 133 forming the bypass flow path 132 along the longitudinal direction of the partition wall 133. The sample introduced through the inlet 120 flows along the path of the bypass flow path 132, and a part thereof may pass through the filter flow path 134 formed in the partition wall 133. In this process, bubbles, vacuoles, or fine particles impurity (200) included in the sample may be filtered through the filtration channel 134. At this time, the width or the cross-sectional area of the filtration flow path 134 is formed to be smaller than the size of the bubble 200, vesicles or fine particles of impurities, such as the material to be filtered (200) except for the filtered material 200 is the filtration flow path It is desirable to be able to pass through 134.

Various shapes of the filtration flow path 134 for effectively collecting the filtered material 200 will be described with reference to FIGS. 2 to 4.

As illustrated in FIG. 2, the partition wall 133a may be formed of a plurality of micro cylinders spaced apart from each other to have a predetermined interval. The micro cylinders arranged in a line form a partition wall 133a, and a flow path between neighboring partition walls 133a forms a bypass flow path 132. At this time, the filtration flow path 134 can be formed in the space | interval between adjacent micro cylinders in the micro cylinder arranged in a line. As the cross section of the micro-cylinder is formed in a circular shape, the filtration flow path 134 may be formed in a form in which the cross-sectional area becomes smaller and becomes smaller at the point connecting the center of the micro-cylinder along the path through which the sample flows, and then grows again.

Therefore, bubbles, bubbles or impurities in the form of fine particles 200 may be collected without passing through the filter flow passage 134 in a region where the cross-sectional area of the filter flow passage 134 becomes smaller.

In addition, as shown in FIG. 3, the filtration flow path may be formed by a minute gap formed in the partition wall 133b forming the bypass flow path 132. The filtration flow path is gradually reduced along the path through which the sample flows. It is preferable that 134 be formed. In FIG. 3, a tapered inclined wall surface is formed so that the cross-sectional area of the filtration channel 134 gradually decreases, but the shape of the filtration channel 134 is not limited to the shape of FIG. 3 as long as the cross-sectional area thereof is gradually reduced.

When the sample flows along the bypass flow path 132, a part of the sample flows toward the filter flow path 134. In this case, bubbles, bubbles, or fine particles impurity 200 included in the sample also move toward the filtration flow path 134. At this time, as the cross-sectional area of the filtration flow path 134 gradually decreases as shown in FIG. 3, the cross-sectional areas of the inlet end and the outlet end of the filtration flow path 134 are different from each other. In addition, the bubbles 200, the impurities in the form of fine particles, etc. 200 may be collected on the filtering channel 134 without passing through the filtering channel 134.

Furthermore, as shown in FIG. 4, a filtration flow path may be formed by a minute gap formed in the partition wall 133c forming the bypass flow path 132, and at the inlet end, bubbles, vacuoles, or fine particles are filtered. A collecting unit 135 may be formed that is formed larger than the size of the particulate impurities 200 to provide a space for collecting the filtration material 200. The fine gap 136 located at the rear end of the collecting unit 135 is formed to have a smaller cross-sectional area than the collecting unit 135 so that the filtered sample flows out through the fine gap 136 at the rear end of the collecting unit 135.

Accordingly, the collecting unit 135 collects bubbles 200, bubbles, fine particles, impurities, and the like, which are the filtered material 200, and passes the remaining sample except the fine gap 136.

In the exemplary embodiment described with reference to FIGS. 2 to 4, it has been described to filter bubbles, bubbles, impurities, etc. in the form of fine particles through the filtering flow path formed in the partition wall 133, but will be described below with reference to FIGS. 5 to 6. Another form of filtration flow path will be described.

The microfluidic device 100 according to the present invention may be formed by a combination of two substrates 112 and 114 positioned above and below. That is, a partition wall 133 is formed on the first substrate 112 to form the bypass flow passage 132 and the filtering flow passage 134 on the indented surface, and the upper surface of the first substrate 112 is formed on the second substrate. Since the substrate 114 is covered and bonded to each other, the microfluidic device 100 having the bypass passage 132 and the filtering passage 134 formed between the first substrate 112 and the second substrate 114 can be manufactured.

In this case, as shown in FIG. 5, a gap may not be formed between the partition wall 133 and the second substrate 114 such that the upper surface of the partition wall 133 contacts the second substrate 114. As shown in FIG. 6, a horizontal fine gap 134b may be formed between the barrier rib 133 and the second substrate 114 at a predetermined interval.

The horizontal microgap forms the filtration flow path 134b so that only the sample excluding the bubbles, vacuoles, or impurities in the form of fine particles 200 may flow between the microgap 134b. In this case, the filtration flow path 134b formed by the horizontal fine gap may be formed together with the filtration flow path 133a formed in the partition wall 133 described with reference to FIGS. 2 to 5, or may be formed independently.

In addition, the microfluidic device according to the present invention may further include a vent part 138. Referring to FIGS. 1 and 7 to 8, the vent part 138 is a through hole connecting the side surface of the substrate and the bypass flow path 132 to fine bubbles contained in the sample in the filter 130. It is to be discharged to the outside of the fluid element (100).

In this case, the vent 138 is preferably formed in a portion where the path direction of the bypass flow path 132 is switched as shown in FIG. 1, and may be formed in the main channel 140. In addition, in FIG. 1, the vent part 138 is formed on the bypass channel 132 or the main channel 140 having an oblique shape, but the channel formed on the substrate 110 and the side surface of the substrate 110 are formed. It is also applied to the microfluidic device 100 having various types of flow paths other than an oblique form in the form of through-holes connected therebetween, and it is possible to discharge bubbles contained in a sample flowing along the flow path to the outside of the microfluidic device.

Vent portion 138 is a hydrophobic fine gap to block the outflow of the liquid sample while allowing only the gas to be discharged to the outside of the microfluidic device (100). The width and height of the vent part 138 may be formed very finely in comparison with the bypass flow path 132. In this case, as illustrated in FIG. 7, the pillar of the vent part 138 may have a nano-sized pillar. ) 139 can be formed to effectively block the outflow of the liquid sample.

In addition, although not shown, a negative pressure forming part may be formed outside the vent part 138 to effectively discharge the bubbles contained in the sample due to the pressure difference between the inside and the outside of the microfluidic device 100. There is a number.

Hereinafter, the operation of the microfluidic device 100 according to an embodiment of the present invention will be described.

9 is a view showing the flow of the sample in the filtration unit in the embodiment of Figure 3, Figure 10 is a view showing the flow of the sample in the filtration unit in the embodiment of FIG.

When the fluid sample is introduced through the inlet 120, the fluid passes through the filtration unit 130.

At this time, the main flow of the sample in the filtration unit 130 is moved along the path that the direction of movement repeatedly changes from side to side in an oblique form through the bypass flow path 132 described above. In addition, a portion of the sample flowing along the bypass flow path 132 may include a partition wall 133 forming the bypass flow path 132 and a filtration flow path 134 formed between the partition wall 133 and the second substrate 114. It is filtered and moved along. In this case, as described above with reference to FIG. 3, the filtration flow path 134 may be formed only in the partition 133, and as described above with reference to FIG. 4, the filtration flow path 133a formed in the partition 133 may be formed. In addition, the filtration flow path 133b may be formed in a horizontal gap between the partition wall 133 and the second substrate 114.

Accordingly, as shown in FIGS. 9 and 10, the flow moving along the direction of the bypass flow path 132 and the flow moving along the filtering flow path 134 are combined in the filter 130. .

When a portion of the sample flowing along the bypass flow path 132 moves along the filter flow path 134, bubbles, vacuoles, or impurities in the form of fine particles 200 also move toward the filter flow path 134. At this time, bubbles, vacuoles, or fine particles 200 may be collected on the filtration flow path 134 to filter the sample. It is preferable that the shape of the filtration flow path 134 for allowing the filtration material 200 to be easily collected is formed in the shape as shown in FIGS. 2 to 4.

At this time, in the present invention, since the plurality of filtration flow paths 134 are formed along the partition wall 133 forming the bypass flow path 132, the filtration material 200 is continuously formed along the flow path of the bypass flow path 132. It can be filtered.

In addition, bubbles included in the sample moving along the bypass flow path 132 may be discharged to the outside through the vent unit 138 described above.

The sample passing through the filtration unit 130 may pass through the main channel 140 of the diagonal shape to the outlet 150. When the sample passes through the main channel 140, bubbles, vacuoles, or impurities in the form of fine particles 200 are filtered through the filtration unit 130, so that the inflow is blocked. It is possible to solve the problem that the main channel 140 is blocked due to the fine particles 200 and the like.

The scope of the present invention is not limited to the above-described embodiment, but may be embodied in various forms of embodiments within the scope of the appended claims. Without departing from the gist of the invention claimed in the claims, it is intended that any person skilled in the art to which the present invention pertains falls within the scope of the claims described in the present invention to various extents which can be modified.

100: microfluidic device 110: substrate
112: first substrate 114: second substrate
120: inlet 130: filtration unit
132: bypass flow path 133, 133a, 133b, 133c: partition wall
134, 134a, 134b: filtration flow path 135: collecting part
138: vent 139: pillar
200: filtration material

Claims (4)

A flow path formed on the substrate to move the liquid sample; And
A vent hole for discharging bubbles formed in the sample to the outside as a through hole connecting the side of the substrate and the flow path,
Bubble discharge microfluidic device in which a plurality of nano pillars are formed in the through hole. The method of claim 1,
The flow path is a bubble discharge microfluidic device which is a flow path in the form of a diagonal line that the direction of movement is repeatedly changed from side to side. delete The method of claim 1,
Bubble discharge microfluidic device further comprising a negative pressure forming portion for forming a negative pressure on the side of the substrate formed with the vent.

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