DE102010041972A1 - A microfluidic device and method of controlling fluid flow using the same - Google Patents

Abstract

A microfluidic device includes: a lower plate with a first channel; a first upper plate immovably stacked on the lower plate and having grooves on an upper portion thereof, a fluid inlet and a fluid outlet formed at positions corresponding to both ends of the first channel; and a second upper plate movably inserted into the grooves of the first upper plate and having a second channel, a hole connected to a right end of the second channel, and a third channel connected to the right side of the hole is.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority from the Korean Intellectual Property Office Korean Patent Application No. 10-2009-0096431 from October 9, 2009 as well 10-2010-0051082 of May 31, 2010, the disclosures of which are incorporated herein by reference.

BACKGROUND OF THE INVENTION

Field of the invention

The present invention relates to a microfluidic device and a method of controlling a fluid flow using the same, and more particularly to a technique for controlling a fluid flow simply and precisely by merely moving a second top plate in a microfluidic device formed by sequential stacking Laminating) a lower plate, a first upper plate fixed to an upper portion of the lower plate, and movably inserting the second upper plate into a groove (s) of the first upper plate.

Description of the Related Art

The prior art technique for controlling fluid flow includes a technique for controlling the shape and size of a channel, a technique for working an inner wall of a channel to have hydrophilicity or hydrophobicity, a technique for using pressure or electrical energy, or the like like that.

The technique for controlling the shape and size of a channel, wherein the width and depth of a channel are different to adjust a flow velocity of a fluid based on hydromechanics, and wherein the shape of the channel is controlled to induce a large or small capillary force is conventionally used to adjust fluid flow. However, the prior art technique for controlling fluid flow by merely adapting the shape and size of a channel is limited to application to the field of biochips, with capabilities to maintain a particular transfer rate of a fluid in a microchannel Maintaining a certain reaction time in a reactive region as well as stopping a fluid transfer and the like are essential for quantization of analyzes.

Moreover, the technique of controlling a fluid by treating the inner wall of a channel to have hydrophilicity or hydrophobicity is limited to application to the biochip area where a fluid is stopped at a desired position or to a desired one Position to be transferred. For example, there is a technique for stopping fluid flow by establishing a hydrophobic region on a channel to maintain a certain reaction time. When a fluid hits the hydrophobic region, the flow of fluid is stopped due to the properties of expelling the fluid from the inner wall of the channel, and in this case, the period of time in which the fluid is stopped is proportional to the range and length of the hydrophobic region. However, while most materials have hydrophobic properties in an initial phase, the materials generally tend to change to have hydrophilicity as the length of time that they encounter the fluid increases. As time passes, therefore, the fluid passes through the hydrophobic region at a very slow rate. Therefore, when the hydrophobic portion of the channel is arranged to stop the flow of fluid to maintain a certain reaction time, the hydrophobicity of the hydrophobic portion becomes insufficient due to absorption of ambient humidity, amount of reactant, inertial force of the fluid flow at the reaction portion results in a situation in which the reactant can flow out to the hydrophobic region at the reaction area. In addition, when the reaction time is to be adjusted by this method, a certain portion of the channel must be treated to have hydrophobicity, and accordingly, considering the physical and chemical properties of a fluid used, a suitable material and processing method must be developed.

Moreover, the technique of controlling fluid flow using pressure requires a pressure adjusting device such as a syringe pump, a peristaltic pump, and the like, resulting in an increase in the size of a diagnostic system having these system elements, and because the cost of configuring the system This is not acceptable in a point-of-care (POCS) market, which seeks low and low cost elements, by the cost of the pressure adjustment device and not by the cost of the system elements. Further, the technique of controlling fluid flow using electrical energy is advantageous in that the size of a system can be reduced, but it is disadvantageous in that it only has a lot of power limited cases is applicable. Moreover, in order to apply electrical energy, an electrode must be formed on an element, which requires a very unusual, particular shape and scheme according to the properties of fluids, and in order to transmit an electrical signal to the interior of the element must be configured different devices are combined. Although it is a small, compact system, it is therefore very difficult to manufacture and implement the system. In particular, when an element performs reactions at different stages, as the electrical properties of a fluid change depending on the stage, the electrical energy must be adjusted depending on the stage, which complicates the processes.

SUMMARY OF THE INVENTION

One aspect of the present invention provides a microfluidic device fabricated by sequentially stacking a bottom plate, a first top plate fixed to an upper portion of the bottom plate, and a second top plate movably inserted into a groove ) of the first upper plate capable of simply and precisely controlling fluid flow by only moving the second upper plate.

According to one aspect of the present invention, there is provided a microfluidic device comprising: a lower plate having a first channel; a first upper plate immovably stacked on the lower plate and having grooves on an upper portion thereof, a fluid inlet and a fluid outlet formed at positions corresponding to both ends of the first channel; and a second upper plate movably inserted in the grooves of the first upper plate and having a second channel, a hole connected to a right end of the second channel, and a third channel connected to the right side of the hole is.

According to another aspect of the present invention, there is provided a method of controlling fluid flow using a microfluidic device formed by sequentially stacking a bottom plate, a first top plate, and a second top plate such that the first top plate is at an upper portion the lower plate is fixed and the second upper plate is movably inserted in grooves of the first upper plate, comprising: injecting a fluid into a first channel formed on the lower plate through a fluid inlet formed on the first upper plate ; and, when the first passage is filled with the fluid injected through the fluid inlet so that the fluid flow is stopped, moving the second upper plate to connect a fluid outlet formed on the first upper plate to a second passage is formed on the second upper plate.

BRIEF DESCRIPTION OF THE DRAWINGS

The above-described and other aspects, features and other advantages of the present invention will become more apparent from the following detailed description when read in conjunction with the accompanying drawings, in which:

1 an exploded perspective view of a microfluidic device according to an exemplary embodiment of the present invention;

2a to 2c are perspective views for explaining a method for controlling a fluid flow using a microfluidic device according to an exemplary embodiment of the present invention;

3 Fig. 12 is a schematic view explaining a phenomenon in which a droplet is generated at a fluid outlet of a first upper plate; and

4 Fig. 10 is a sectional view showing the implementation of an immune response using a microfluidic element according to an exemplary embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. However, the invention may be embodied in many different forms, and it should not be interpreted as limited to the embodiments described herein. Rather, these embodiments are provided for a thorough and complete disclosure of the invention and will fully convey the scope of the invention to those skilled in the art. If it is to be understood that a detailed explanation of a related, known function or construction unnecessarily detracts from the gist of the present invention, such explanation will be omitted, which, nonetheless, would be understood by one of ordinary skill in the art.

In the drawings, the shapes and dimensions may be exaggerated for the purpose of illustration, and like or similar components will use like reference numerals throughout.

It will be understood that it should be understood that an element is "connected" to another element, it may be directly connected to the other element, or intervening elements may also be present. In contrast, when it is pointed out that one element is "directly connected" to another element, there are no intermediary elements. Unless expressly stated to the contrary, the word "comprising" and variations such as "comprises" or "comprising" is to be understood to include specified elements, but not to exclude any other elements.

1 FIG. 11 is an exploded perspective view of a microfluidic device according to an exemplary embodiment of the present invention. FIG.

The microfluidic device according to an exemplary embodiment of the present invention includes a lower plate 10 as well as two upper plates 20 and 30 on, which is sequential on the lower plate 10 are stacked.

In this case, the first top plate is 20 which adjoins the lower plate, on the lower plate 10 fixed, and the second top plate 30 is in grooves (or recesses) of the first upper plate 20 inserted and moves freely along the grooves.

A first channel 11 which has a preset width and depth is at a left portion of the lower plate 10 educated.

The first top plate 20 has a groove to allow the second top plate 30 can be introduced into it. Along a central portion of a lower surface of the groove is a flow path 21 formed having a portion which projects upwardly with respect to the lower surface. Führungsschienennuten 22 into the side protrusions of the second upper plate 30 are to be introduced are formed on a lower portion on the side of the groove. At the river way 21 are a fluid inlet 23 and a fluid outlet 24 educated. The fluid inlet 23 and the fluid outlet 24 are formed at positions, both ends of the first channel 11 match that on the lower plate 11 is trained.

A channel having a preset width and depth is on a lower portion of the second upper plate 30 designed to form a flow path. A hole 31 is formed to penetrate a portion of the second upper plate, and a reservoir 32 is designed to be right off the hole 31 from the hole 31 is spaced. Regarding the on the second upper plate 30 Trained channel becomes the area of the channel on the left side of the hole 31 referred to as the second channel, and a channel between the hole 31 and the reservoir 32 is referred to as the third channel.

The lower plate mentioned above 10 , the first top plate 20 and the second upper plate 30 are sequentially stacked to form a microfluidic device having a two-piece structure. On the corresponding layers flow paths are formed, along which a fluid flows. The fluid is first injected into a flow path of the lower layer, and while the second plate 30 is moved, the flow path of the lower layer and that of the upper layer are connected to allow the fluid to flow from the lower layer to the upper layer.

2a to 2c FIG. 15 are perspective views for explaining a method of controlling fluid flow using a microfluidic device according to an exemplary embodiment of the present invention. FIG.

In the structure where the top plate 10 , the first top plate 20 and the second upper plate 30 are sequentially stacked, as in 2a is shown, first, the movable second plate 30 far right at an upper area of the first upper panel 20 positioned.

When the fluid passes through the on the first top plate 20 trained fluid inlet 23 injected into the flows in the 2a state the fluid along the first channel 11 on the lower plate 10 is formed, and then at the fluid outlet 24 stopped. When a sufficient amount of fluid through the fluid inlet 23 in the first channel 1 is introduced, the fluid flows upward through the fluid outlet 24 to form a droplet, as in 3 is shown. Because the top layer does not have any channel with the fluid outlet 24 In this case, the droplet is maintained to have a certain size and shape, provided there is no force on the fluid inlet 23 is exerted, whereby the fluid is stopped.

Thereafter, the second upper plate 30 moved to the left, leaving the second channel of the second upper plate 30 with the fluid outlet 24 can be connected as in 2 B is shown. Then the fluid flows along the first channel 11 has moved through the fluid outlet 24 to the second channel of the second plate 30 and then moves up to an area with the hole 31 connected along the second channel. Soon after, the fluid hits the hole 31 , an empty space so that it can not continue to flow and is stopped.

Thereafter, the second upper plate 30 moved to the left, leaving the third channel of the second upper plate 30 with the fluid outlet 24 can be connected as in 2c shown. Then it flows inside the first channel 11 remaining fluid through the third channel, a new flow path to the reservoir 32 to reach.

In this way, in the microfluidic device according to an exemplary embodiment of the present invention, the movement and the stopping of the fluid can be accurately controlled by only moving the upper second plate.

4 FIG. 10 is a sectional view showing the implementation of an immune response using a microfluidic element according to an exemplary embodiment of the present invention. FIG. Specifically explained 4 an example of implementing reactions of various steps, such as a sandwich immunoassay in an element.

If, as in 4 (a) shown, blood 1 is injected through the fluid inlet, in a state where the second upper plate is positioned on the far right side, blood cells contained in the blood are passed through a filter 41 removed, which is installed inside the first channel, and only blood plasma (serum) 3 happens through the filter 41 to reach a range where a first-stage antigen-antibody reaction of the sandwich immunoassay occurs.

A fluorescent nanoparticle detection antibody assembly consisting of a fluorescent substance or fluorescent nanoparticles 43 as well as detection antibodies 42 which are physically or chemically linked is coated and formed in a first-stage antigen-antibody reaction region, ie, a region on the right side of the filter 41 , and a reaction area is positioned that reacts with a particular material.

As in 4 (b) is shown when the blood plasma component 3 Completely fills the first stage antigen-antibody reaction area, the fluid flow stopped and there is a sufficient reaction. At this time, the blood plasma component hits 3 to the fluorescent nanoparticle detection antibody assembly applied to the first-stage antigen-antibody reaction region, and because the fluid is stopped and can not continue to flow until the second top plate is connected to the fluid outlet, the antigen-antibody Reaction to take place in a sufficient amount of time.

As in 4 (c) 2, after the second top plate is moved to the left so that the second channel of the second top plate is connected to the fluid outlet, the fluorescent nanoparticle detection antibody blood plasma assembly moves through the fluid outlet to the second channel of the top layer. A specific antibody 44 which is specific for an antibody is solidly formed at the entrance of the second channel, and a detection unit is positioned to detect the fluorescent nanoparticle detection antibody blood plasma assembly. Therefore, the fluorescent nanoparticle detection antibody blood plasma assembly that has moved to the second channel encounters the specific antibody 44 the detection unit included in the second channel to undergo a second stage reaction. In this case, the fluid filling the second channel can not flow through the open hole and is stopped.

If the second stage reaction has been done adequately, as in 4 (d) As shown, the second upper plate is moved to the left so that the third channel of the second upper plate can be connected to the fluid outlet. Accordingly, the fluorescent nanoparticle detection antibody blood plasma assemblies that are not containing the specific antibody 44 have been connected to the detection unit, mostly pressed to the left side, and only the arrangements that have been connected to the detection unit remain. While the blood plasma components that have not reacted with the fluorescent nanoparticle detection antibody blood plasma assembly remaining in the first channel will continue to be introduced into the third channel, the arrays remaining on the surface will not be reacted but will be pushed to the left to remove the blood plasma Reach reservoir. Accordingly, all non-specifically responsive elements are removed without having participated in the reaction.

As in 4 (e) Thereafter, the amount of fluorescent nanoparticles associated with antibodies is measured using LD / PD.

As described above, therefore, the microfluidic device can accurately control the movement and the stopping of the fluid by the simple operation of moving the second top plate and allow unnecessary fluids that do not participate in the reaction to flow out as well as allow a new fluid can be fed continuously, whereby the reaction is completed.

As described above, according to exemplary embodiments of the invention in the A microfluidic device formed by sequentially stacking the lower plate, the first upper plate fixed to the upper portion of the lower plate, and the second upper plate movably inserted into a groove of the first upper plate, a fluid flow by agitation The second top plate can be easily and precisely controlled.

Moreover, because the microfluidic device has a simpler structure, elements can be implemented as compact and small elements as well as at a low cost, and the microfluidic device can be used extensively, regardless of the type of fluid in use.

Moreover, an analysis that performs multiple-step reactions, such as a sandwich immunoassay, can be implemented by the microfluidic device, and a fluid can be more accurately analyzed by precisely controlling fluid flow.

While the present invention has been shown and described in connection with exemplary embodiments, it will be apparent to those skilled in the art that modifications and variations can be made without departing from the spirit and scope of the invention as defined in the appended claims.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• KR 10-2009-0096431 [0001]
• KR 10-2010-0051082 [0001]

Claims (15)

A microfluidic device comprising: a lower plate having a first channel; a first upper plate immovably stacked on the lower plate and having grooves on an upper portion thereof, a fluid inlet and a fluid outlet formed at positions corresponding to both ends of the first channel; and a second upper plate movably inserted in the grooves of the first upper plate and having a second channel, a hole connected to a right end of the second channel, and a third channel connected to the right side of the hole , The apparatus of claim 1, wherein the first top plate further includes a flow path having a portion that projects upwardly with respect to a bottom surface of the grooves along the bottom surface of the grooves, and guide rail grooves that are lateral projections of the second top plate allow it to be inserted into it. Apparatus as claimed in any one of the preceding claims, wherein the second top plate further comprises a reservoir connected to the right end of the third channel. Apparatus according to any one of the preceding claims, wherein the first to third channels each have a preset width and depth. An apparatus according to any one of the preceding claims, wherein, when the second top plate is positioned on the far right side of the first top plate and the fluid injected through the fluid inlet into the first channel completely fills the first channel, fluid flow is stopped , The apparatus of claim 5, wherein, when the second top plate moves leftward to connect the fluid outlet and the second channel, the fluid that has filled the first channel flows through the fluid outlet to the second channel. The apparatus of claim 6, wherein the fluid that has moved to the second channel flows along the second channel and the fluid is stopped when the fluid hits the hole. The apparatus of claim 7, wherein the fluid remaining in the interior of the first passage moves through the fluid outlet to the third passage as the second top plate moves leftward to connect the fluid outlet and the third passage. Apparatus according to any one of the preceding claims, wherein the first channel comprises: a filter; and a reaction member formed by coating a fluorescent nanoparticle detection antibody assembly and responsive to a particular material that has passed through the filter. The device of claim 9, wherein a specific antibody is solidly formed on the second channel, and wherein the second channel comprises a detection unit that detects an assembly that forms when the fluorescent nanoparticle antibody assembly and the specific material react. A method of controlling fluid flow using a microfluidic device formed by sequentially stacking a bottom plate, a first top plate and a second top plate so that the first top plate is fixed to an upper portion of the bottom plate and the second top plate movably inserted in grooves of the first upper plate, the method comprising: Injecting a fluid into a first channel formed on the lower plate through a fluid inlet formed on the first upper plate; and, when the first channel is filled with the fluid injected through the fluid inlet so that the fluid flow is stopped, moving the second upper plate to connect a fluid outlet formed on the first upper plate and a second channel formed on the second upper plate. The method of claim 11, further comprising: when the fluid having moved from the first passage through the fluid outlet to the second passage flows along the second passage and is stopped by an empty space, moving the second upper plate to connect the fluid outlet and a third passage directed to it second upper plate is formed. The method of claim 12, further comprising: Performing an antigen-antibody reaction between a reaction region provided inside the first channel and a target material contained in the fluid after the fluid has been injected into the first channel. The method of claim 13, further comprising: Detecting an arrangement according to the antigen-antibody reaction by a detection unit provided inside the second channel after the second channel has been connected. The method of claim 14, wherein a nonspecific reactive element that has not been detected upon detecting the array is removed by connecting the third channel.

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