KR20090014871A - Microfluidic valve, manufacturing process of the microfluidic valve and microfluidic device comprising the microfluidic valve - Google Patents

Abstract

A microfluidic valve, a method for preparing the microfluidic valve, and a microfluidic apparatus containing the microfluidic valve are provided to minimize the effect of the manufacturing process of a microfluidic valve on other elements by omitting the heating process of the entire platform. A microfluidic valve(10) comprises a platform(100) which comprises two substrates(110, 120) adhered so as to face each other; a channel(20) which is formed in a first depth so as to allow fluid to flow between the two substrates; a valve gap which is arranged in at least some segment of section of the channel and has a second depth shallow than the first depth; and a valve plug(33) which is arranged in so as to fill the valve gap and comprises a valve material comprising a plurality of heat radiating particles, wherein the heat radiating particles absorbs the electromagnetic wave on a phase transfer material of solid stage to radiate heat in such an amount for melting the phase transfer material.

Description

Microfluidic valve, manufacturing process of the microfluidic valve and microfluidic device comprising the microfluidic valve

The present invention relates to a microfluidic valve, and more particularly, to a microfluidic valve for controlling the flow of a fluid flowing along a structure in a platform, a method of manufacturing the microfluidic valve, and a microfluidic device including the microfluidic valve. It is about.

In general, a device that performs a biological or chemical reaction by manipulating a small volume of fluid is called a microfluidic device. Microfluidic devices include microfluidic structures disposed in platforms of various shapes, such as chips and discs, and microfluidic structures include chambers capable of confining fluids, channels through which fluids can flow, and valves capable of regulating the flow of fluids. It may include, and be made by various combinations thereof.

In order to perform experiments involving biochemical reactions in a small chip, a lab-on-a-chip is designed to place microfluidic structures on a chip-like platform and perform various stages of fluid processing and manipulation. It is called a lab-on-a chip. The driving pressure is required to transfer the fluid in the microfluidic structure. Capillary pressure may be used as the driving pressure, or a pressure by a separate pump may be used. Recently, disc-type microfluidic devices have been proposed for disposing a microfluidic structure on a disc-shaped platform, moving a fluid using centrifugal force, and performing a series of operations. This is also known as a Lab CD or a Lab-on a disk.

In order to perform complex tasks in a microfluidic device such as a lab-on-a-chip or a lab-on-a-disc, a plurality of microfluidic valves which are disposed at various parts and individually control the flow of fluid are required. In addition, in order to mass-produce a microfluidic device, a manufacturing method capable of efficiently manufacturing the microfluidic valve together with other structures such as a chamber and a channel is required.

On the other hand, a valve for controlling the flow of the fluid using a phase change material that is solid at room temperature and melted at high temperature has been proposed. Anal. Published in 2004. Chem. Vol. The substrate for biochemical reaction published on pages 1824 to 1831 of 76 and the substrate for biochemical reaction published on pages 3740 to 3748 of the same document are provided with a valve consisting of only paraffin wax and provided with heating means for melting the paraffin wax. do. However, the valve provided therein requires a considerable amount of paraffin wax to close the microchannel, and a large heating means must be provided to melt the large amount of paraffin wax, thereby miniaturizing and integrating the substrate for biochemical reaction. it's difficult. In addition, it takes a lot of heating time to melt the paraffin wax, and it is difficult to precisely control the channel opening time.

It is an object of the present invention to provide a microfluidic valve and a microfluidic device including the same, which quickly and accurately perform an operation of controlling a flow of a fluid flowing along a structure in a platform by an external electromagnetic wave energy source.

In addition, an object of the present invention is to provide a method of efficiently manufacturing while increasing the reliability of the microfluidic valve. In particular, it is an object of the present invention to provide a manufacturing method for minimizing the effect that the process for manufacturing the microfluidic valve may have on other components when the microfluidic valve is applied.

The microfluidic valve according to the present invention includes a platform including two substrates bonded to each other; A channel formed to a first depth to allow fluid to flow between the two substrates; A valve gap disposed in at least a portion of the channel and formed to a second depth shallower than the first depth; And a valve plug disposed to fill the valve gap, the valve plug including a plurality of exothermic particles mixed with a plurality of exothermic particles absorbing electromagnetic waves in a phase change material having a solid state at room temperature to release heat to melt the phase change material. It includes.

The two substrates may be bonded to each other at least a portion including the outer periphery of the channel. At least one of the two substrates may have a protruding pattern formed along the outer periphery of the channel, and the surface of the protruding pattern may be bonded to the surface of the opposing substrate.

On the other hand, the microfluidic valve may further include a valve material chamber disposed adjacent to the channel to receive valve material to form the valve plug and to be connected to the valve gap to allow the molten valve material to move. In this case, the two substrates may be joined to each other at least a portion including the channel and the outside of the valve material chamber. At least one of the two substrates has a protruding pattern formed along the periphery of the channel and the valve material chamber, and the surface of the protruding pattern may be bonded to the surface of the opposing substrate.

The phase change material may be a wax, a gel, or a thermoplastic resin. The wax may be at least one selected from the group consisting of paraffin wax, microcrystalline wax, synthetic wax, and natural wax. The gel may be at least one selected from the group consisting of polyacrylamide, polyacrylates, polymethacrylates, and polyvinylamides. The thermoplastic resin is COC (cyclic olefin copolymer), PMMA (polymethylmethacrylate), PC (polycarbonate), PS (polystyrene), POM (polyoxymethylene), PFA (perfluoralkoxy), PVC (polyvinylchloride), PP (polypropylene), PET (polyethylene terephthalate) ), At least one selected from the group consisting of polyetheretherketone (PEEK), polyamide (PA), polysulfone (PSU), and polyvinylidene fluoride (PVDF).

The exothermic particles may be metal oxide particles. The metal oxide may be at least one selected from the group consisting of Al ₂ O ₃ , TiO ₂ , Ta ₂ O ₃ , Fe ₂ O ₃ , Fe ₃ O _4, and HfO ₂ . The micro heating particles may be polymer particles, quantum dots, or magnetic beads.

The method of manufacturing a microfluidic valve according to the present invention includes a three-dimensional structure in which a channel gap having a first depth and a valve gap having a second depth shallower than the first depth is formed in at least a portion of the channel between two surfaces facing each other. (A) preparing an upper and a lower substrate having a; Disposing and solidifying the molten valve material at a position corresponding to the valve gap of the lower substrate; (C) bonding the upper substrate and the lower substrate to each other to form a platform; (D) irradiating electromagnetic material to the valve material from outside the platform to melt the valve material to fill the valve gap, and then solidify the valve material to form a valve plug. Here, the valve material may be a mixture of a plurality of exothermic particles absorbing electromagnetic waves in a phase change material having a solid state at room temperature to release heat to melt the phase change material.

In the step (a), a lower substrate having a three-dimensional structure forming the channel and the valve gap is formed on the upper surface, and an upper substrate covering at least the region including the three-dimensional structure. Further, in the step (a), a lower substrate having a three-dimensional structure formed on the upper surface to form a valve material chamber connected to the channel, the valve gap and the valve gap, and an upper substrate covering at least the region including the three-dimensional structure; And in step (b), dispose the valve material in the valve material chamber, and in step (d), the molten valve material may move into the valve gap to fill the valve gap.

As a first method for increasing the reliability of the upper and lower substrate bonding, in the step (a), the lower substrate further comprises a protrusion pattern formed along the periphery of the three-dimensional structure, at least the three-dimensional structure and the protrusion pattern An upper substrate may be provided to cover an area including the upper substrate, and in step (c), an adhesive may be applied to a surface of the protruding pattern of the lower substrate, and the lower substrate may be covered and adhered to the upper substrate. In a second method, in step (a), a lower substrate further comprising a protrusion pattern formed along the outer periphery of the three-dimensional structure, and an upper substrate covering at least the region including the three-dimensional structure and the protrusion pattern, In the step (c), an adhesive may be applied to the upper substrate in a form corresponding to the protruding pattern, and the upper substrate may be covered with the upper substrate and bonded. In this case, the adhesive may be applied using the inkjet printing method in the step (c).

On the other hand, in the manufacture of a microfluidic valve having a valve material chamber, in step (d), electromagnetic waves are irradiated until some of the valve material in the valve material chamber is vaporized, and the pressure of the vaporized vapor is reduced. The molten valve material can thereby be moved into the valve gap.

Microfluidic device according to the present invention, a platform comprising two substrates bonded to each other; And a microfluidic structure disposed within the platform and including a chamber, a channel and a microfluidic valve for manipulation of the microfluid, wherein the microfluidic valve is formed at a first depth to allow fluid to flow between the two substrates. channel; A valve gap disposed in at least a portion of the channel and formed to a second depth shallower than the first depth; And a valve plug disposed to fill the valve gap, the valve plug including a plurality of exothermic particles mixed with a plurality of exothermic particles absorbing electromagnetic waves in a phase change material having a solid state at room temperature to release heat to melt the phase change material. It includes.

The two substrates may be bonded to each other at least a portion including the outer periphery of the microfluidic structure. Furthermore, at least one of the two substrates may have a protruding pattern formed along the periphery of the microfluidic structure, and the surface of the protruding pattern may be bonded to the surface of the opposing substrate.

The valve material chamber may further include a valve material chamber disposed adjacent to the channel to receive the valve material to form the valve plug and to be connected to the valve gap to allow the molten valve material to move.

The platform has a rotatable disk shape, and may transfer fluid in the microfluidic structure by centrifugal force due to the rotation of the platform.

According to the present invention, there is an effect of providing a microfluidic valve and a microfluidic device including the same to quickly and accurately perform the operation of controlling the flow of the fluid flowing along the structure in the platform by an external electromagnetic wave energy source.

In addition, the present invention provides a method of efficiently manufacturing while increasing the reliability of the microfluidic valve. In particular, the present invention has the effect of minimizing the effect that the process for the production of the microfluidic valve can affect other components by excluding the process of heating the platform as a whole when manufacturing the microfluidic device to which the microfluidic valve is applied. have.

Hereinafter, with reference to the accompanying drawings will be described embodiments of the present invention;

1 shows an embodiment of a microfluidic valve according to the invention, and FIG. 2 shows a cross section of the embodiment shown in FIG. 1. The figures show an example of a microfluidic valve 10 that can be employed in a microfluidic device capable of manipulating a microfluid within the platform 100 to perform a biological or chemical reaction. The platform 100 may be provided in various forms such as rectangular chip form, disk form, fan form or trapezoidal form. Both sides of the channel 20 of the microfluidic valve 10 may be connected to a structure such as a chamber or another channel disposed in the platform 100 (see FIG. 9).

The platform 100 may be made of a plastic material such as acrylic (PMMA), PDMS, PC, etc., which is easy to mold and whose surface is biologically inert. However, the present invention is not limited thereto, and a material suitable for chemical, biological stability, optical transparency, and mechanical processing is sufficient. The platform 100 may be formed of two substrates 110 and 120. The platform is formed by forming a three-dimensional structure (for example, a three-dimensional structure formed in an intaglio) corresponding to a chamber (not shown) or a channel 20 on a surface where the upper substrate 110 and the lower substrate 120 face each other, and bonding them. It may provide a space in which the fluid can be stored or flow inside the (100). Bonding of the two substrates 110 and 120 may be performed by various methods, such as adhesive or solvent bonding ultrasonic welding or laser welding using an adhesive or a double-sided adhesive tape.

According to the present embodiment, the microfluidic valve 10 is disposed in the channel 20 of the first depth D1 and a partial section of the channel 20, and has a second depth smaller than the first depth D1. A valve gap G having a D2. The valve gap G is defined by an upper surface of the valve gap forming portion 21 raised from the bottom of the channel 20 and a bottom surface of the upper substrate 120 of the platform 100. The depth D2 of the valve gap G may be large enough to fill the valve gap G by capillary action when the valve material to be described later is melted. The specific value of the second depth D2 may be determined in consideration of various factors such as a contact angle between the molten valve material and the upper and lower substrates 110 and 120. As an example, when the depth D1 of the channel 20 is 1 mm, the depth D2 of the valve gap G may be 0.1 mm.

In the valve gap G, a valve plug 33 for blocking the flow of fluid through the valve gap G is disposed. The valve plug 33 is solidified again after the valve material disposed in the valve gap G is melted by the energy of electromagnetic waves radiated from the outside of the platform 100 during the manufacturing process of the microfluidic valve 10. In the process, the valve gap G is filled across the width direction.

The valve material constituting the valve plug 33 is a mixture of a plurality of exothermic particles absorbing electromagnetic waves and dissipating heat to melt the phase change material in a phase change material having a solid state at room temperature. The phase change material may be a wax. The wax melts when heated to turn into a liquid state. As the wax, for example, a paraffin wax, a microcrystalline wax, a synthetic wax, a natural wax, or the like can be employed.

The phase change material may be a gel or a thermoplastic resin. As the gel, polyacrylamide, polyacrylates, polymethacrylates, polyvinylamides, or the like may be employed. In addition, the thermoplastic resin, COC (cyclic olefin copolymer), PMMA (polymethylmethacrylate), PC (polycarbonate), PS (polystyrene), POM (polyoxymethylene), PFA (perfluoralkoxy), PVC (polyvinylchloride), PP (polypropylene), Polyethylene terephthalate (PET), polyetheretherketone (PEEK), polyamide (PA), polysulfone (PSU), and polyvinylidene fluoride (PVDF) may be employed.

The exothermic particles may have a diameter of 1 nm to 100 μm to move freely in the valve gap G. The exothermic particles have a property of rapidly generating a high temperature when the electromagnetic wave energy is supplied by a method such as laser irradiation, and evenly dispersing the wax. The exothermic particles may have a core including a metal component and a hydrophobic surface structure to have these properties. For example, the exothermic particle may have a particle structure having a core made of Fe and a plurality of surfactants that are bonded to the Fe to surround the Fe.

Typically, the exothermic particles are stored dispersed in a carrier oil. The carrier oil is also preferably hydrophobic so that the exothermic particles having a hydrophobic surface structure can be evenly dispersed. The valve material may be prepared by pouring and mixing a carrier oil in which the exothermic particles are dispersed in a molten phase change material.

The heating particles are not limited to a specific material, and may also be in the form of quantum dots or magnetic beads. In addition, the exothermic particles may be, for example, metal oxide particles such as Al ₂ O ₃ , TiO ₂ , Ta ₂ O ₃ , Fe ₂ O ₃ , Fe ₃ O _4, or HfO ₂ .

The upper substrate 120 and the lower substrate 110 constituting the platform 100 has a junction portion 115 to which a portion of the surfaces facing each other are bonded. The junction 115 includes an outer portion of the channel 20 to prevent leakage of the fluid in the channel 20 described above. The junction 115 may be formed in a band shape along the outer periphery of the channel 20. The junction 115 may be formed in the above-described form by various methods depending on a method of bonding the two substrates 110 and 120. For example, in the case of using an adhesive, the adhesive is coated on the one of the bottom surface of the upper substrate 120 or the upper surface of the lower substrate 110 by using a patterning method such as inkjet printing and the like. The substrates 110 and 120 may be stacked and bonded together.

On the other hand, the junction 115 may include a protrusion pattern (not shown) formed to surround the outer periphery of the channel 20. For example, an intaglio structure defining the channel 20 is formed on an upper surface of the lower substrate 110, and a strip-shaped portion including an outer portion thereof protrudes higher than the remaining portion to provide a protruding pattern (not shown). The surface of the protruding pattern may allow the upper substrate 120 to be bonded to the bottom surface. Features of this embodiment will become more apparent from the description of FIGS. 7 to 9 below.

The microfluidic valve 10 described above is a normally closed valve. That is, the valve gap G is blocked before operation to block the flow of fluid through the channel 20, and after operation, the valve gap G is opened to allow the fluid to pass. For the operation of the microfluidic valve 10 may use the same electromagnetic energy source (not shown) used in the formation of the valve plug 33. When the valve plug 33 is irradiated with electromagnetic waves such as, for example, a laser beam, the heating particles dispersed in the valve plug 33 absorb the energy and rapidly generate heat, and the phase change material is melted by the heat, and the valve The valve material forming the plug 33 becomes fluid, and when pressure is applied to one side of the channel 20, the molten valve material moves to a deeper portion outside the valve gap G. As a result, fluid may flow through the channel 20.

The results of the experiment measuring the reaction time of the aforementioned microfluidic valve 10 are as follows. The working fluid pressure was maintained at 46 kPa on the test chip for the experiment. A syringe pump (Havard PHD2000, USA) and a pressure sensor (MPX 5500DP, Freescale semiconductor Inc., AZ, USA) were used to maintain the pressure. As the electromagnetic wave energy source (not shown), a laser light source having an emission wavelength of 808 nm and an output power of 1.5 W was used. Data on the reaction time of the microfluidic valve 10 was obtained through analysis of the results of the high speed photographing apparatus (Fastcam-1024, Photron, CA, USA). The valve material is a so-called magnetic material, in which magnetic beads having an average diameter of 10 nm as ferrofluid dispersed in a carrier oil are mixed with ferrofluid and paraffin wax in a ratio of 1 to 1, that is, the volume ratio of magnetic fluid is 50%. Wax was used. In general, as the volume fraction of the magnetic fluid increases, the reaction time is shortened. However, apart from this, when the volume ratio of the magnetic fluid increases to 70% or more, the maximum hold-up pressure of the valve plug tends to be lowered. Therefore, the volume ratio of the magnetic fluid to be included in the valve plug 33 in the microfluidic valve 10 may be determined through a compromise between the demand for reaction time and the demand for maximum allowable pressure.

The reaction time from the time when the valve plug of the microfluidic valve 10 was irradiated with a laser beam until the valve plug was melted to open the channel was 0.012 seconds. It can be seen that the reaction time of the conventional wax valve was much faster than the reaction time was 2 to 10 seconds.

Figure 3 shows another embodiment of the microfluidic valve according to the present invention, Figure 4 shows a cross section of the embodiment shown in Figure 3 above. The microfluidic valve 11 according to the present embodiment may further include a valve material chamber 22 for storing the valve material to form the valve plug 34. The valve material chamber 22 is disposed adjacent to the valve gap G and is connected to the valve gap G. In the manufacturing process of the microfluidic valve 11, the valve material filled in the valve material chamber 22 is melted by an electromagnetic energy source (not shown) outside the platform 100 into the valve gap G. It moves and solidifies again to form the valve plug 34. In this case, the junction 115 is preferably formed along the periphery of the chamber 20 and the valve material chamber 22.

The microfluidic valve 11 according to the present embodiment may be used as a normally closed valve as well as the microfluidic valve 10 according to the embodiment of FIG. 1, as well as a normally open valve. It may be used as. When used as a closed valve, the microfluidic valve 11 may be provided with the valve gap G open and the valve material filled in the valve material chamber 22. When trying to block the flow of fluid through the channel 20, electromagnetic energy is applied to the valve material in the valve material chamber 22 to melt. The pressure due to the volume expansion of the valve material causes the molten valve material to move into the valve gap G to block the flow of fluid. In this case, the amount of energy applied to the valve material in the valve material chamber 22 may be such that a portion of the valve material may be vaporized and its volume may expand rapidly.

Hereinafter, a method of manufacturing a microfluidic valve according to the present invention will be described with reference to Examples. The method of manufacturing a microfluidic valve below may be applied to the production of a microfluidic device including a microfluidic valve according to the present invention.

5a to 5c show the manufacturing process of the microfluidic valve according to the embodiment of FIG. First, the lower substrate 110 and the upper substrate 120 are prepared. The upper surface of the lower substrate 110 is provided with a three-dimensional structure for providing the channel 20 and the valve gap forming portion 21. The three-dimensional structure may be an intaglio structure, as shown in the figure. However, the present invention is not limited thereto, and a structure capable of defining the width and depth of the channel 20 and the valve gap forming unit 21 may be sufficient. The lower substrate 120 having the three-dimensional structure as described above may be prepared by etching or cutting a substrate having a flat plate shape, or may be molded using a mold. The upper substrate 120 may adopt a flat substrate. The upper substrate 120 preferably has a high transmittance with respect to electromagnetic waves, and more preferably, may be an optically transparent substrate. The upper substrate 120 does not have a hole at least in an area facing the valve gap forming portion 21. By removing the holes from the upper substrate 120, the molding of the upper substrate 120 may be facilitated, and leakage of the fluid or pressure loss may be prevented through the holes.

Then, a predetermined amount of molten valve material 31 is dispensed onto the valve gap forming portion 21. At this time, the amount of the valve material 31 may be determined in consideration of the above-described depth and width of the valve gap, and the required internal pressure. The dispensing operation of the valve material 31 can be performed at room temperature, and the valve material 31 in the dispensed liquid state is solidified.

Next, the upper substrate 120 and the lower substrate 110 are bonded. As described above, the bonding method may be performed by various methods such as adhesion using adhesive or double-sided adhesive tape, solvent bonding ultrasonic welding, laser welding, or the like. Here, the method using an adhesive is demonstrated as an example. An adhesive is applied to the bonding portion 115 including the outside of the channel 20. In this case, the surface on which the adhesive is applied may be an upper surface of the lower substrate 110 or a bottom surface of the upper substrate 120. After applying the adhesive, the two substrates 110 and 120 are stacked and adhered to form the platform 100.

Then, the electromagnetic wave is irradiated to the region 50A including the valve gap using the electromagnetic wave energy source 50 provided outside the platform 100. The electromagnetic wave energy source 50 may be, for example, a laser light source. In that case, it may include at least one laser diode. The laser irradiated from the laser light source has an energy that does not denature the structure in the platform 100 and the valve material, and may be a pulse laser having an output of at least 1 mJ / pulse, alternatively at least 14 mW It may be a continuous wave laser having the above output. The laser irradiated from the laser light source may have a wavelength of 400 to 1300 nm.

However, the present invention is not limited thereto. As the electromagnetic wave energy source 50, a device capable of irradiating electromagnetic waves of a predetermined wavelength selected from electromagnetic waves having various wavelengths, such as microwave, infrared, visible light, ultraviolet ray, and X-ray, may be applied. Moreover, it is more preferable if it is the apparatus which can irradiate this electromagnetic wave intensively to a near target. The wavelength of the electromagnetic wave energy source 50 is preferably a range that is well absorbed by the heating particles contained in the valve material. Therefore, the device for generating electromagnetic waves in the electromagnetic wave energy source 50 may be appropriately selected according to the material and surface conditions of the heating particles.

When the valve material 31 is melted in the valve gap using the electromagnetic wave energy source 50, the molten valve material may be formed by capillary action between the valve gap forming part 21 and the upper substrate 110. A valve plug 33 is formed which fills the valve gap across the width direction and solidifies again and stops the flow of fluid when no more energy is applied. However, in order for the valve material 31 to form the valve plug 33, the method of locally applying heat to the region 50A including the valve gap is not limited to the above-described one method. For example, a heat source such as a hot plate may be locally contacted with the region 50A including the valve gap to heat the valve material 31 and the valve gap by heat conduction.

6a to 6c show the manufacturing process of the microfluidic valve according to the embodiment of FIG. As in the above-described embodiment, first, the upper substrate 120 and the lower substrate 110 are prepared. When the lower substrate 110 is provided, the lower substrate 110 may further include a three-dimensional structure defining the valve material chamber 22 in addition to the channel 20 and the valve gap forming portion 21 described above. The valve material chamber 22 may also be provided by an intaglio structure. Next, a predetermined amount of molten valve material 32 is dispensed into the valve material chamber 22. This process can also be done at room temperature.

Then, the upper substrate 120 and the lower substrate 110 are bonded to form the platform 100. In this case, the junction 115 to which the two substrates 110 and 120 are bonded may include at least an outer portion of the channel 20 and the valve material chamber 22. In the case where the microfluidic valve 11 is employed as the closing valve, the process can be completed.

In the case of employing the microfluidic valve 11 as an open valve, the region 50A including the valve material chamber 22 using the electromagnetic energy source 50 outside the platform 100 after completing the bonding process. ) To investigate electromagnetic waves. The valve material in the valve material chamber 22 is melted to move between the valve gap forming portion 21 and the upper substrate 120, that is, the valve gap. At this time, energy is applied to the inside of the valve material chamber 22 until some of the valve material 32 is vaporized, and the molten valve material is released out of the valve material chamber 22 by the pressure due to the rapid volume expansion. You can also The valve material filling the valve gap solidifies again when the energy supply is interrupted to form the valve plug 34. In this case, too, the method of locally applying heat to the region 50A including the valve gap in order for the valve material 32 to form the valve plug 34 is limited to one of the above-described methods. no. For example, a heat source such as a hot plate may be locally contacted with the region 50A including the valve gap to heat the valve material 32 and the valve gap by thermal conduction.

7 shows an example of a method of bonding the upper substrate and the lower substrate during the manufacturing process of the microfluidic valve according to the present invention. When bubbles are generated in the junction when the upper substrate 120 and the lower substrate 110 are bonded, leakage of fluid or loss of pressure is likely to occur, and there is a risk that the junction is separated again. In order to prevent this, when the lower substrate 110 is provided, the protruding pattern 115P may be formed in a portion where the channel 20 and the valve material chamber 22 include an outer portion. The protruding pattern 115P is formed higher than the rest of the lower substrate 110 and has a flat surface. The protruding pattern 115P may be formed in a band shape along the periphery of the channel 20 and the valve material chamber 22. The height of the protrusion pattern 115P defines the width and depth of the channel 20 together with the three-dimensional pattern described above.

In this case, the upper substrate 120 may adopt a flat substrate, or have another protrusion pattern (not shown) corresponding to the protrusion pattern 115P of the lower substrate 110 on the bottom surface 120R. It may be.

After preparing the upper substrate 120 and the lower substrate 110, an adhesive 115A may be applied to the surface of the protruding pattern 115P. In this case, a liquid may be used as the adhesive 115A, and the adhesive may be selectively applied only to the surface of the protruding pattern 115P by using a patterning method such as an inkjet printing method.

Figure 8 shows another example of a method for bonding the upper substrate and the lower substrate during the manufacturing process of the microfluidic valve according to the present invention. As in the embodiment of FIG. 7 described above, the lower substrate 110 having the protruding pattern 115P and the upper substrate 120 having a flat plate shape are prepared. Then, the adhesive 115A is applied to the bottom surface 120R of the upper substrate 120 in a form corresponding to the protrusion pattern 115P.

In this case, too, a liquid state can be used as the adhesive 115A, and the adhesive can be applied using a patterning method such as an inkjet printing method. During inkjet printing, the volume of the liquid adhesive droplets discharged may be 1 pl to 100 µl. In addition, the adhesive 115A may be, for example, a UV curable adhesive. In this case, after the adhesive is applied, ultraviolet rays are irradiated to the junction while the two substrates 110 and 120 are stacked and adhered to each other. In this case, when a force is applied in a direction in which the two substrates 110 and 120 are in close contact with each other, pressure is concentrated on the surface of the protruding pattern 115P and a corresponding portion of the upper substrate bottom surface 120R to improve the reliability of the bonding. . In addition, the kind of energy applied to a joining part can be changed according to the kind of adhesive agent, or the kind of joining method.

As described above, in the method of applying the adhesive 115A to the bottom of the upper substrate 120, the adhesive enters the channel 20 to narrow the flow path in the process of applying the adhesive, or the chamber in the lower substrate 110 (not shown). Prevent mixing with the reaction solution pre-injected.

9 shows an embodiment of a microfluidic device according to the present invention. In this embodiment, the platform 100 has a disk shape, and has a microfluidic structure including a plurality of microfluidic valves 10, channels 20, and chambers 41 and 42 in the platform 100. will be. The platform 100 may rotate, and fluid is transported in the microfluidic structure by centrifugal force due to the rotation.

The platform 100 includes an upper substrate 120 and a lower substrate 110 bonded to each other. The lower substrate 110 is provided with a three-dimensional structure for providing the chamber (41, 42), the channel 20 and the valve gap forming portion 21, the protrusion pattern 115P is provided along the outer periphery of the microfluidic structure Can be. The protruding pattern 115P may be formed in a band shape, but the width of the protrusion pattern 115P does not always have to be constant and does not necessarily have a band shape.

When the sample chamber 41 is located near the center of the platform 100 among the plurality of chambers 41 and 42, the upper substrate 120 includes a sample inlet 41A connected to the sample chamber 41. Can be prepared.

In manufacturing the microfluidic device, the lower substrate 110 and the upper substrate 120 as described above are respectively provided, and the valve material 31 is distributed to the valve gap forming portion 21 on the lower substrate 120. Then, the reaction liquid is injected into the reaction chamber 42. Then, when bonding the upper substrate 120 and the lower substrate 110, the protrusion pattern 115P of the lower substrate 110 on the bottom surface of the upper substrate 120, as in the embodiment of FIG. Form an adhesive pattern corresponding to). Thereafter, when the two substrates 110 and 120 are stacked and adhered to each other and the energy required for bonding is applied, the aforementioned platform 100 is formed. Then, the microfluidic valve 10 may be irradiated with electromagnetic waves to melt and solidify the valve material 31 to provide a microfluidic device.

Although the preferred embodiment according to the present invention has been described above, this is merely exemplary, and it will be understood by those skilled in the art that various modifications and equivalent other embodiments are possible. Therefore, the protection scope of the present invention should be defined by the appended claims.

1 shows an embodiment of a microfluidic valve according to the present invention.

Figure 2 shows a cross section of the embodiment shown in Figure 1 above.

Figure 3 shows another embodiment of a microfluidic valve according to the present invention.

4 shows a cross section of the embodiment shown in FIG. 3.

5a to 5c show the manufacturing process of the microfluidic valve according to the embodiment of FIG.

6a to 6c show the manufacturing process of the microfluidic valve according to the embodiment of FIG.

7 shows an example of a method of bonding the upper substrate and the lower substrate during the manufacturing process of the microfluidic valve according to the present invention.

Figure 8 shows another example of a method for bonding the upper substrate and the lower substrate during the manufacturing process of the microfluidic valve according to the present invention.

9 shows an embodiment of a microfluidic device according to the present invention.

<Description of Symbols for Main Parts of Drawings>

10, 11: microfluidic valve unit 20: channel

21: valve gap forming portion 22: valve material chamber

31, 32: valve material 33, 34: valve plug

41: sample chamber 42: reaction liquid chamber

50: electromagnetic energy source 100: platform

110: lower substrate 115: bonding portion

120: upper substrate

Claims (34)

A platform comprising two substrates bonded to each other; A channel formed to a first depth to allow fluid to flow between the two substrates; A valve gap disposed in at least a portion of the channel and formed to a second depth shallower than the first depth; And The valve plug is formed so as to fill the valve gap, the valve plug is made of a valve material mixed with a plurality of exothermic particles absorbing electromagnetic waves in a phase-transfer material in a solid state at room temperature to release the heat to melt the phase-transfer material Containing microfluidic valve. The method of claim 1, The two substrates are microfluidic valve, characterized in that at least a portion including the outer channel is bonded to each other. The method of claim 1, At least one of the two substrates has a protruding pattern formed along the outer periphery of the channel, the microfluidic valve characterized in that the surface of the protruding pattern is bonded to the surface of the facing substrate. The method of claim 1, And a valve material chamber disposed adjacent said channel to receive valve material to form said valve plug and associated with said valve gap to allow said molten valve material to move. The method of claim 4, wherein Wherein said two substrates are joined to each other at least a portion comprising said channel and an outer portion of said valve material chamber. The method of claim 4, wherein At least one of the two substrates has a protruding pattern formed along the periphery of the channel and the valve material chamber, the surface of the protruding pattern being bonded to the surface of the opposing substrate. The method according to claim 1 or 4, The phase change material is a wax (wax), gel (gel), or a microfluidic valve, characterized in that the thermoplastic resin. The method of claim 7, wherein The wax may be at least one selected from the group consisting of paraffin wax, microcrystalline wax, synthetic wax, and natural wax. Flow valve. The method of claim 7, wherein The gel is at least one selected from the group consisting of polyacrylamide, polyacrylates, polymethacrylates, polymethacrylates, and polyvinylamides. . The method of claim 7, wherein The thermoplastic resin is a cyclic olefin copolymer (COC), polymethylmethacrylate (PMMA), polycarbonate (PC), polystyrene (PS), polyoxymethylene (POM), perfluoralkoxy (PFA), polyvinylchloride (PVC), polypropylene (PP), PET (polyethylene) terephthalate, polyetheretherketone (PEEK), polyamide (PA), polysulfone (PSU), and polyvinylidene fluoride (PVDF). The method according to claim 1 or 4, The exothermic particle is a microfluidic valve, characterized in that the metal oxide particles. The method of claim 11, The metal oxide micro flow valve comprising at least one selected from the group consisting of Al ₂ O ₃ , TiO ₂ , Ta ₂ O ₃ , Fe ₂ O ₃ , Fe ₃ O _4, and HfO ₂ . The method according to claim 1 or 4, The micro heating particle is a microfluidic valve, characterized in that the polymer particles, quantum dot (quantum dot), or magnetic beads (magnetic bead). (A) providing an upper and a lower substrate having a three-dimensional structure having a channel having a first depth and a valve gap having a second depth shallower than the first depth in at least some sections of the channel between two facing surfaces; ; Disposing and solidifying the molten valve material at a position corresponding to the valve gap of the lower substrate; (C) bonding the upper substrate and the lower substrate to each other to form a platform; (D) locally heating the valve material from outside the platform to melt the valve material to fill the valve gap and then solidify again to form a valve plug, The valve material is a method of manufacturing a microfluidic valve, characterized in that a plurality of exothermic particles are absorbed by the phase-transfer material in a solid state at room temperature to emit heat to melt the phase-transfer material. The method of claim 14, In the step (a), manufacturing a microfluidic valve, characterized in that the upper substrate is provided with a lower substrate having a three-dimensional structure forming the channel and the valve gap, and an upper substrate covering at least the region containing the three-dimensional structure Way. The method of claim 15, In the step (a), a lower substrate having a three-dimensional structure is formed on the upper surface and forming a valve material chamber connected to the channel, the valve gap and the valve gap, and an upper substrate covering at least the region including the three-dimensional structure and , In step (b), dispose a valve material in the valve material chamber, In said step (d), said molten valve material moves to said valve gap to fill said valve gap. The method according to claim 15 or 16, In the step (a), to provide a lower substrate further comprising a projection pattern formed along the outer periphery of the three-dimensional structure, and an upper substrate covering at least the region including the three-dimensional structure and the protrusion pattern, In the step (c), a method of manufacturing a microfluidic valve characterized in that the adhesive is applied to the surface of the protruding pattern of the lower substrate and the lower substrate is covered with the upper substrate. The method according to claim 15 or 16, In the step (a), to provide a lower substrate further comprising a projection pattern formed along the outer periphery of the three-dimensional structure, and an upper substrate covering at least the region including the three-dimensional structure and the protrusion pattern, In the step (c), the method of manufacturing a microfluidic valve characterized in that the adhesive is applied to the upper substrate in the form corresponding to the protruding pattern and the lower substrate is covered with the upper substrate. The method of claim 18, Method of producing a microfluidic valve, characterized in that for applying the adhesive using the inkjet printing method in the step (c). The method of claim 16, In step (d), the microfluidic is irradiated with electromagnetic waves until some of the valve material in the valve material chamber is vaporized, and the molten valve material is moved to the valve gap by the pressure of vaporized vapor. Method of manufacturing the valve. The method of claim 14, In the step (d), the method of producing a microfluidic valve, characterized in that for irradiating the electromagnetic wave locally to the region including the valve material and the valve gap. The method of claim 14, In the step (d), the method of manufacturing a microfluidic valve, characterized in that for heating by contacting a heat source locally to the region including the valve material and the valve gap. The method of claim 14, The phase change material is a wax, a gel, or a method for producing a microfluidic valve, characterized in that the thermoplastic resin. The method of claim 23, wherein The wax is at least one selected from the group consisting of paraffin wax, microcrystalline wax, synthetic wax, and natural wax. Method of manufacturing the valve. The method of claim 23, wherein The gel is at least one selected from the group consisting of polyacrylamide, polyacrylates, polymethacrylates, polymethacrylates, and polyvinylamides. Method of preparation. The method of claim 23, wherein The thermoplastic resin is a cyclic olefin copolymer (COC), polymethylmethacrylate (PMMA), polycarbonate (PC), polystyrene (PS), polyoxymethylene (POM), perfluoralkoxy (PFA), polyvinylchloride (PVC), polypropylene (PP), PET (polyethylene) terephthalate), PEEK (polyetheretherketone), PA (polyamide), PSU (polysulfone), PVDF (polyvinylidene fluoride) at least any one selected from the group consisting of a microfluidic valve manufacturing method. The method of claim 14, The exothermic particle is a method for producing a microfluidic valve, characterized in that the metal oxide particles. The method of claim 27, The metal oxide is Al ₂ O ₃ , TiO ₂ , Ta ₂ O ₃ , Fe ₂ O ₃ , Fe ₃ O ₄ And, at least one selected from the group consisting of HfO ₂ Preparation of microfluidic valve Way. The method of claim 14, The micro heating particle is a method of producing a microfluidic valve, characterized in that the polymer particles, quantum dots (magnetic dots), or magnetic beads (magnetic bead). A platform comprising two substrates bonded to each other; And A microfluidic structure disposed within the platform and including a chamber, a channel and a microfluidic valve for manipulation of the microfluid; The microfluidic valve, A channel formed to a first depth to allow fluid to flow between the two substrates; A valve gap disposed in at least a portion of the channel and formed to a second depth shallower than the first depth; And A valve plug, which is arranged to fill the valve gap, is made of a valve material in which a plurality of exothermic particles are mixed, which absorbs electromagnetic waves in a phase change material having a solid state at room temperature and releases heat to melt the phase change material. Microfluidic device comprising a. The method of claim 30, The two substrates are microfluidic device characterized in that at least a portion including the outer portion of the microfluidic structure bonded to each other. The method of claim 30, At least one of the two substrates has a protruding pattern formed along the outer periphery of the microfluidic structure, the microfluidic device characterized in that the surface of the protruding pattern is bonded to the surface of the facing substrate. The method of claim 30, The microfluidic valve, And a valve material chamber disposed adjacent said channel to receive valve material to form said valve plug and associated with said valve gap to allow said molten valve material to move. The method of claim 30, The platform has a rotatable disk shape, microfluidic device, characterized in that for transporting the fluid in the microfluidic structure by the centrifugal force according to the rotation of the platform.

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