KR20180134803A - Micro-fluidic device discharging bubble - Google Patents

Abstract

The present invention relates to a micro-fluidic device discharging bubbles. The micro-fluidic device discharging bubbles according to the present invention includes: a flow path for moving a liquid sample by being formed on a substrate; and a vent unit operating as a penetration port for connecting the side surface of the substrate and the flow path, and discharging bubbles generated in the sample to the outside. An objective of the present invention is to provide a micro-fluidic device discharging bubbles, which can prevent the clogging of a main channel by filtered materials by previously filtering or removing bubbles, vacuoles, microparticles, etc.

Description

[0001] MICRO-FLUIDIC DEVICE DISCHARGING BUBBLE [0002]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a microfluidic device, and more particularly, to a microfluidic device having micro or nano-sized microchannels, such as a biochip, a diagnostic device, a lab on a chip or a MEMS To the microfluidic device.

Microchannel or nano-sized microchannels, which allow fluid samples to flow, are widely used in biochips, diagnostic devices, lab-on-a-chip or MEMS (Micro Electro Mechanical Systems) .

When a microfluidic device having such a microchannel is used, bubbles, liquid droplets, or minute particle type impurities may be generated in preparation of a sample, a process of supplying a sample, or a process of flowing a sample inside the device. At this time, microchannels are frequently clogged by such bubbles, liquid vacuoles, or fine particle type impurities. If the microchannels are clogged in this manner, the microchannel-applied device may not operate normally or may suffer serious problems such as deterioration of function.

Therefore, in order to stably maintain the performance of the related device, it is necessary to solve the phenomenon that the microchannels are clogged by such bubbles, liquid crystals or fine particle type impurities.

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SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to solve such conventional problems, and it is an object of the present invention to solve the problems of the prior art by providing a method of filtering or removing bubbles, Thereby preventing the main channel from clogging.

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

According to the present invention, the above object can be accomplished by providing a bypass flow path formed in a substrate and being a serpentine line flow path in which the moving direction is repeatedly changed left and right; And a filtration flow path formed in a partition wall between neighboring flow paths flowing in different directions in the bypass flow path and filtering at least one of bubbles, liquid drops, and fine particles in the sample supplied to the bypass flow path. Can be achieved by a fluid device.

According to the present invention, the above object can also be accomplished by providing a bypass flow path, which is a serpentine flow path formed on a substrate and in which the moving direction is repeatedly changed in a lateral direction; And baffles, vacuoles, and fine particles in the sample supplied to the bypass flow path as fine gaps formed by the partition walls being spaced apart from the upper portion, And a filtration flow path for filtering at least one of the plurality of filtration channels.

Here, the size of the filtration flow path may be smaller than the size of the bypass flow path.

Here, the substrate may include a first substrate having a partition wall defining the bypass flow path and the filtration flow path, and a second substrate covering the first substrate.

The apparatus may further include a vent portion for discharging the bubble to the outside as a through-hole connecting the side surface of the substrate and the bypass flow path.

Here, the partition may be formed of a plurality of microcylinders spaced apart from each other, and the filtration channel may be formed between gaps between adjacent microcylinders.

Here, the filtration flow path may be formed of a plurality of fine gaps formed in the partition wall, and a collecting part may be formed on the inlet side of the filtration flow path, which is a space for collecting the filtered material.

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

An inlet through which the sample flows into the substrate; A micro- or nano-sized main channel through which the sample flows; And an outlet through which the sample is discharged, wherein a bypass flow path including the filtration flow path may be formed between the inlet and the main channel.

According to another aspect of the present invention, there is provided a liquid ejecting apparatus including: a flow path formed on a substrate to move a liquid sample; And a vent portion for discharging the bubble to the outside as a through hole connecting the side surface of the substrate and the flow path.

Here, the flow path may be a serpentine flow path in which the moving direction is repeatedly changed in the lateral direction.

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

The apparatus may further include a negative pressure forming part for forming a negative pressure on a side surface of the substrate on which the vent part is formed.

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

Further, since a plurality of filtration flow paths are formed in the partition walls forming the bypass flow path, a large amount of material can be filtered along the path of the bypass flow path.

In addition, the advantage of being able to efficiently remove bubbles or the like without additional parts or processes by simultaneously realizing bubbles, liquid vacuums, or filtration parts for filtering fine particles contained in the sample in the molding process of the microfluidic device including the main channel have.

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

The details of the embodiments are included in the detailed description and the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS The advantages and features of the present invention, and the manner of achieving them, will be apparent from and elucidated with reference to the embodiments described hereinafter in conjunction with the accompanying drawings. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. To fully disclose the scope of the invention to those skilled in the art, and the invention is only defined by the scope of the claims. Like reference numerals refer to like elements throughout the specification.

Hereinafter, the present invention will be described with reference to the drawings for explaining a 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. FIG. 2 is an enlarged view of a part of the filtration part of FIG. 1 and shows an embodiment of a partition wall forming a filtration flow path FIG. 3 is a view showing another embodiment of the partition wall forming the filtration flow path, FIG. 4 is a view showing another embodiment of the partition wall forming the filtration flow path, and FIG. 5 is a cross- FIG. 6 is a cross-sectional view taken along line AA of FIG. 1 according to another embodiment of the present invention, and FIG. 7 is a cross-sectional view taken along line AA of FIG. FIG. 8 is a partial view of the side view of FIG. 1 showing another embodiment of the vent portion. FIG.

The microfluidic device 100 according to an embodiment of the present invention includes a microchannel-based biochip capable of analyzing gene defects, protein distribution, and reaction patterns by binding biological molecules such as DNA and proteins onto a small substrate, , A micro-or nano-sized channel, a mixer, a pump, and a structure of a valve function on a single chip so that experiments or analyzes that can be performed in a conventional laboratory can be performed with a very small sample at high speed and high efficiency. A MEMS (Micro Electro Mechanical Systems) element requiring a chip on a chip, a flow control using a micro flow path, or a diagnostic element for performing separation and analysis of a very small amount of biological fluid such as blood Microchannels are formed on the substrate 110 through which a fluid sample flows to the element 100 constituting the microchannel.

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

As shown in FIG. 1, the main channel 140 may be formed to have a nano- or micro-sized microchannel so that the moving direction of the main channel 140 is changed repeatedly in the form of a serpentine line.

The microfluidic device 100 according to the present invention may have a filtration part 130 formed between the inlet 120 and the main channel 140. As described above, the sample introduced through the inlet 120 may include or may include bubbles, liquid drops, or impurities in the form of fine particles. Such bubbles, vacuoles, or impurities in the form of fine particles 200 can prevent the flow of the sample when the fluid sample flows in the main channel 140. Accordingly, in the present invention, the filtration part 130 is formed at the front end of the main channel 140 to filter out fine bubbles, liquid fine particles, or impurities in the form of fine particles 200 to prevent them from flowing into the main channel 140 So that the problem of clogging of the flow of the sample in the main channel 140 can be solved.

The fluid particle device 100 in which the filtration part 130 is formed between the inlet 120 and the main channel 140 will be described. However, a fluid particle device composed of only the fluid part 130 is formed, It is also possible to connect them separately to the device.

The filtration unit 130 is formed as a microchannel 132 connecting the inlet 120 and the main channel 140. It is preferable that the direction of movement of the sample is changed repeatedly as shown in FIG. The microchannel 132 may be formed as a serpentine line. The barrier ribs 133 may be formed between the channels 132 through which the sample flows in the neighboring different directions. As shown in FIG. 1, partition walls 133 extending from left and right sides of the substrate 110 are alternately formed, so that a slanted channel 132 in which the moving direction is repeatedly changed can be formed. Hereinafter, the channel 132 formed by the partition 133 will be referred to as a bypass flow path 132. [

Here, the left and right directions are for the sake of convenience of description, and mean, as shown in the drawing, the direction connecting the inlet 120 and the outlet 150 is defined as a left-right direction when the upper and lower directions are defined.

In the present invention, a plurality of filtration flow paths 134 may be formed in the partition 133 forming the bypass flow path 132 along the longitudinal direction of the partition 133. The sample flowing through the inlet port 120 flows along the path of the bypass flow path 132. Part of the sample flows through the filtration flow path 134 formed in the partition 133. In this process, the bubbles, liquid droplets, or impurities in the form of fine particles 200 contained in the sample can be filtered through the filtration flow path 134. At this time, the width or cross-sectional area of the filtration channel 134 is formed to be smaller than the size of the bubble, liquid crystal or impurity in the form of fine particles 200, which is a substance to be filtered, (134). ≪ / RTI >

Various shapes of the filtration channel 134 for effectively trapping the material 200 to be filtered will be described with reference to FIGS. 2 to 4. FIG.

As shown in FIG. 2, the barrier ribs 133a may be formed of a plurality of microcylinders spaced apart with a predetermined gap. The micro cylinders arranged in a line form the partition 133a and the flow path between the adjacent partition 133a forms the bypass flow path 132. [ At this time, in the microcylinders arranged in a line, the filtration flow path 134 can be formed in the gap between the adjacent microcylinders. As the sectional area of the microcylindrical body is formed in a circular shape, the filtration flow path 134 may be formed to have a small cross-sectional area along with the flow path of the sample, and to be minimized at a point connecting the centers of the microcylindrical bodies.

Therefore, in the region where the cross-sectional area of the filtration channel 134 becomes smaller, bubbles, liquid crystal, or impurities in the form of fine particles 200 can be collected without passing through the filtration channel 134.

3, the filtration flow path can be formed in the fine gaps formed in the partition 133b forming the bypass flow path 132. In this case, the cross-sectional area of the filtration flow path is gradually decreased along the path along which the sample flows, It is preferable that the first electrode layer 134 is formed. In FIG. 3, the tapered inclined wall surface is formed so that the cross-sectional area of the filtration path 134 gradually decreases. The shape of the filtration path 134 is not limited to the shape of FIG. 3 as long as the cross-sectional area is gradually decreased.

When the sample flows along the bypass flow path 132, a part thereof is directed to the filtration flow path 134. At this time, bubbles, liquid vacuums, or impurities in the form of fine particles 200 included in the sample are also moved toward the filtration flow path 134. 3, the cross-sectional areas of the inlet end and the outlet end of the filtration flow path 134 are different from each other as the cross-sectional area of the filtration flow path 134 gradually becomes smaller. As shown in FIG. 3, Impregnated particles 200 in the form of liquid or fine particles can be collected on the filtration channel 134 without passing through the filtration channel 134.

Further, as shown in FIG. 4, the filtration flow path can be formed in the fine gap formed in the partition 133c forming the bypass flow path 132. In this case, the filtration flow path can be formed by bubbles, A collecting part 135 may be formed which is formed to be larger than the particle size of the inorganic substance 200 and provides a space for collecting the filtering substance 200. The fine gaps 136 located at the rear end of the collecting part 135 are formed to have a smaller cross sectional area than the collecting part 135 so that the filtered sample flows out through the fine gaps 136 at the rear end of the collecting part 135.

Accordingly, bubbles, liquid droplets, or impurities in the form of fine particles 200, which are the substances 200 to be filtered, are collected in the collecting unit 135, and the remaining samples are passed through the fine gaps 136 at the rear end.

In the embodiment described with reference to FIGS. 2 to 4, bubbles, liquid drops, or impurities in the form of fine particles 200 are filtered through the filtration flow path formed in the partition 133. However, as shown in FIGS. 5 to 6 Another type of filtration flow path will be described.

The microfluidic device 100 according to the present invention can be formed by coupling two substrates 112 and 114 located on the upper and lower sides. That is, the first substrate 112 is provided with a partition wall 133 for forming a bypass flow path 132 and a filtration flow path 134 on a fine-grained surface, and the upper surface of the first substrate 112 is divided into a second The microfluidic device 100 having the bypass flow path 132 and the filtration flow path 134 formed between the first substrate 112 and the second substrate 114 can be manufactured by covering and bonding the substrate 114.

5, a gap may not be formed between the barrier rib 133 and the second substrate 114 such that the upper surface of the barrier rib 133 is in contact with the second substrate 114, , A horizontal fine gap 134b may be formed between the barrier rib 133 and the second substrate 114 by a predetermined distance as shown in FIG.

This horizontal fine gap forms the filtration flow path 134b so that only the sample excluding bubbles, liquid droplets, or the impurity substance 200 in the form of fine particles can flow out through the fine gaps 134b. At this time, the filtration flow path 134b formed by horizontal fine gaps may be formed together with the filtration flow path 133a formed in the partition 133 described with reference to FIGS. 2 to 5, or may be formed independently.

The microfluidic device according to the present invention may further include a vent portion 138. Referring to FIGS. 1 and 7 to 8, the vent portion 138 is a through-hole connecting the side surface of the substrate and the bypass flow path 132, To be discharged to the outside of the fluid device 100.

At this time, as shown in FIG. 1, the vent portion 138 is preferably formed at a portion where the path direction of the bypass flow path 132 is switched, and may also be formed in the main channel 140. 1, the bent portion 138 is formed on the diagonal bypass channel 132 or the main channel 140. However, since the channel formed on the substrate 110 and the side surface of the substrate 110 The bubbles included in the sample flowing along the flow path can be discharged to the outside of the microfluidic device.

The vent portion 138 allows the gas to be discharged to the outside of the microfluidic device 100 while blocking the leakage of the liquid sample through the fine hydrophobic gap. The width and height of the vent portion 138 are preferably formed to be finer than the bypass flow path 132. At this time, as shown in FIG. 7, a nano-sized pillar ) 139 may be formed to effectively block the outflow of the liquid sample.

Although not shown, a negative pressure forming portion that forms a negative pressure outside the vent portion 138 may be formed. Due to the pressure difference between the inside and the outside of the microfluidic device 100, the bubbles contained in the sample can be effectively discharged to the outside There is a number.

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

FIG. 9 is a view showing the flow of the sample in the filtration section in the embodiment of FIG. 3, and FIG. 10 is a diagram showing the flow of the sample in the filtration section in the embodiment of FIG.

When the fluid sample flows 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 moves along the path in which the moving direction is repeatedly changed in the diagonal direction through the bypass flow path 132 described above. Part of the sample flowing along the bypass flow path 132 includes the partition 133 forming the bypass flow path 132 and the filtration flow path 134 formed between the partition 133 and the second substrate 114 Filtered and moved. 3, the filtration flow path 134 may be formed only in the partition 133, and the filtration flow path 133a formed in the partition 133 as described above with reference to FIG. 4 And the filtration flow path 133b may be formed in the horizontal gap between the partition 133 and the second substrate 114 together.

Therefore, as shown in FIGS. 9 and 10, a flow that moves along the direction of the bypass flow path 132 and a flow that moves along the filtration flow path 134 are generated in a complex manner within the filtration part 130 .

When a part of the sample flowing along the bypass flow path 132 moves along the filtration flow path 134, bubbles, liquid drops, or impurities in the form of fine particles 200 also move toward the filtration flow path 134. At this time, bubbles, liquid vacuoles, or impurities 200 in the form of fine particles are collected on the filtration channel 134, and the sample can be filtered. It is preferable that the shape of the filtration channel 134 that enables the filtration material 200 to be easily collected is formed in the shape as shown in Figs. 2 to 4 described above.

Since the plurality of filtration channels 134 are formed along the partition 133 forming the bypass channels 132 in the present invention, the filtration materials 200 are continuously supplied along the flow path of the bypass channels 132 It can be filtered.

The bubbles included in the sample moving along the bypass flow path 132 may be discharged to the outside through the vent portion 138 described above.

The sample having passed through the filtration unit 130 can be discharged to the outflow port 150 through the main channel 140 having a slant shape. Since the sample 200 is filtered through the filtration unit 130 to block the inflow of air bubbles, liquid droplets, or fine particle type impurities 200 contained in the sample when the sample passes through the main channel 140, It is possible to solve the problem that the main channel 140 is clogged due to the fine particle type impurities 200 or the like.

The scope of the present invention is not limited to the above-described embodiments, but may be embodied in various forms of embodiments within the scope of the appended claims. It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present invention as defined by the appended claims.

100: microfluidic device 110: substrate
112: first substrate 114: second substrate
120: inlet 130:
132: Bypass flow path 133, 133a, 133b, 133c:
134, 134a, 134b: Filtration channel 135:
138: Vent section 139: Column
200: filtration material

Claims (4)

A flow path formed on the substrate to move the liquid sample; And
And a vent for discharging the bubble formed in the sample to the outside as a through hole connecting the side surface of the substrate and the flow path. The method according to claim 1,
Wherein the flow path is a serpentine flow path in which a moving direction is repeatedly changed left and right. The method according to claim 1,
And a plurality of nano pillars are formed in the through-hole. The method according to claim 1,
And a negative pressure forming part for forming a negative pressure on a side surface of the substrate on which the vent part is formed.

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