This application is a Continuation of International Application No. PCT/JP2011/068512 filed on Aug. 15, 2011, which claims benefit of priority to Japanese Patent Application No. 2010-271253 filed on Dec. 6, 2010. The entire contents of each application noted above are hereby incorporated by reference.
1. Field of the Invention
The present invention relates to a method of manufacturing a microchip having a fine flow channel and a circuit formed therein, particularly, a microchip with reduced fluorescence, which is used in fields such as chemistry, biochemistry, and medicine.
2. Description of the Related Art
In fields such as chemistry, biochemistry, and medicine, when a chemical reaction, separation, analysis, detection, and the like are required in a space of a fine flow channel, a microchip, having a fine flow channel and a circuit formed therein, is formed on a silicon substrate or a glass substrate. However, in a method of performing microfabrication on an inorganic material such as silicon or glass, there is a problem in that the method is not suitable for, particularly, one-time disposable use because of a high manufacturing cost and a long manufacturing time.
For this reason, as shown in
However, in the manufacturing method as disclosed in the example of the related art, ultraviolet light is used in the adhesion of the pair of resin substrates, and thus fluorescence is generated on the surfaces of the resin substrates irradiated with the ultraviolet light. For this reason, in fluorescence labeling that performs measurement by applying a fluorescent marker to a specimen, if the microchip is used, there is a problem in that the fluorescence generated on the surfaces of the resin substrates has an adverse effect on the measurement and thus detection accuracy decreases. On the other hand, when an adhesive is used in the adhesion of the pair of resin substrates, the adhesive itself includes a large amount of material that produces fluorescence, and thus there is a problem in that the adhesive has a larger adverse effect on the measurement than the microchip that is created by the irradiation with ultraviolet light.
A method of manufacturing a microchip that has a pair of resin base materials of which facing surfaces are bonded to each other and that has a concave portion formed in at least one of the facing surfaces, the method includes: irradiating the facing surfaces before the pair of resin base materials are bonded to each other, with ultraviolet light which is light having a wavelength of an ultraviolet region, and then irradiating the ultraviolet light-irradiated facing surfaces of the pair of resin base materials, with visible light that substantially includes light having a wavelength of a visible region.
Accordingly, in the method of manufacturing a microchip of the present invention, fluorescent molecules with a fluorescent property which are generated by ultraviolet light are in an excited state by irradiating ultraviolet light-irradiated facing surfaces of a pair of resin base materials with visible light, and electrons move to another polymer contained in the resin base material, and thus the fluorescent molecules become nonfluorescent molecules. Thereby, the fluorescence of the microchip can be reduced.
Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
As shown in
In the visible light process P13 to be described later, it is required that the light transmissive base material 2 is a light transmissive base material through which visible light VL passes. A material such as a cycloolefin polymer (COP), a cycloolefin copolymer (COC), polymethyl methacrylate (PMMA), polycarbonate (PC), polythylene telephthalate (PET), or amorphous polyolefin is used as the light transmissive base material. In particular, the cycloolefin polymer (COP) and the cycloolefin copolymer (COC) are suitably used because these polymers are synthetic resin materials with low intrinsic fluorescence.
In addition, intensity, workability, and adhesion with the light transmissive base material 2 are considered for the resin base material 1. A silicone resin such as a cycloolefin polymer (COP), a cycloolefin copolymer (COC), polymethyl methacrylate (PMMA), polycarbonate (PC), or polydimethylsiloxane (PDMS), or a material such as polythylene telephthalate (PET) or amorphous polyolefin is used as the resin base material. However, similarly to the light transmissive base material 2, the cycloolefin polymer (COP) and the cycloolefin copolymer (COC) are particularly suitably used as the resin base material because these polymers are synthetic resin materials with low intrinsic fluorescence.
Next, a method of manufacturing the microchip 101 will be described.
The method of manufacturing the microchip 101 includes an ultraviolet process P11 of irradiating the facing surfaces 4 before the pair of resin base materials are bonded to each other, with ultraviolet light UV, a bonding process P12 of bringing the facing surfaces 4 after the ultraviolet process P11 into contact with each other to thereby bond the pair of resin base material to each other, and a visible light process P13 of performing irradiation with visible light VL from the light transmissive base material 2 side, which is one resin base material, after the bonding process P12.
First, as shown in
Next, as shown in
In addition, bonding and sealing methods using an adhesive are also considered as a method of bonding the resin base material 1 and the light transmissive base material 2 to each other. However, since the adhesive itself has a large intrinsic fluorescence, a method using an adhesive is not preferable. In addition, bonding and sealing methods using thermal fusion are also considered. However, since the bonding using these methods is generally performed at a temperature equal to or more than a glass transition temperature of a synthetic resin, a substrate is deformed during the bonding, which results in a loss of a function as a microchip. Further, the influence of the substrate deformation becomes more conspicuous when the width of the flow channel is reduced or when a flow channel pattern is formed complicated in shape, and thus it is difficult to obtain a highly-functional microchip in the bonding using thermal fusion.
Finally, as shown in
In addition, when the visible light VL is irradiated in the visible light process P13, the visible light lamp 333 may be used together with an ultraviolet light cut filter that cuts light having a wavelength of equal to or less than 380 nm. Thereby, the light emitted onto the facing surface B4 of the resin base material 1 which includes the concave portion 3 and the facing surface A4 of the light transmissive base material 2 is visible light VL that substantially includes light having a wavelength of 380 nm to 800 nm which includes little ultraviolet light. For this reason, the fluorescent molecules generated in the ultraviolet process P11 can be reliably used as nonfluorescent molecules without newly generating fluorescent molecules with a fluorescent property which are generated by irradiation with ultraviolet light UV. Thereby, the fluorescence of the microchip 101 can be further reduced.
In addition, in the method of manufacturing the microchip 101, the bonding process P12 is performed after the ultraviolet process P11, and the visible light process P13 of performing irradiation with visible light VL after the bonding process P12 is performed. Thereby, the fluorescent molecules with a fluorescent property which are generated by ultraviolet light UV can be reliably used as nonfluorescent molecules, and the resin base material 1 and the light transmissive base material 2 can be reliably bonded to each other without decreasing the adhesion between the resin base material 1 and the light transmissive base material 2. Thereby, it is possible to further reduce the fluorescence of the microchip 101 and to create the microchip 101 that is excellent in pressure resistance, and the like.
Hereinafter, the first embodiment of the present invention will be described in more detail by Example 1. The present invention is not limited to the example below.
First, as the resin base material 1 and the light transmissive base material 2, a pair of resin base materials (70 mm×20 mm, thickness of 2 mm) constituted by a cycloolefin polymer (manufactured by Nippon Zeon Co., Ltd., ZEONEX330R, glass transition temperature of 123° C.) were used. The concave portion 3 of the resin base material 1 and the injection holes 16 of the light transmissive base material 2 were created by performing machining on the resin base materials.
Next, each of the surfaces of the facing surface B4 of the resin base material 1 and the facing surface A4 of the light transmissive base material 2 was irradiated with ultraviolet light UV (wavelength of 172 nm) by using an Xe excimer lamp (manufactured by Ushio Inc., UER20-172A). The irradiation with ultraviolet light UV is performed in the air. A distance between the lamp and the surface of the resin base material 1 and a distance between the lamp and the surface of the light transmissive base material 2 were set to 5 mm, irradiation intensity was set to 10 mW/cm2, and an irradiation time was set to 60 minutes. A surface to be irradiated with ultraviolet light UV was used as the entirety of each of bonding surfaces to be bonded.
Next, the ultraviolet light UV-irradiated surfaces of the resin base material 1 and the light transmissive base material 2 after the ultraviolet process P11 were caused to face each other and to come into contact with each other, and the temperature of the entirety was increased to 100° C. while performing pressing on the entirety with pressure of 0.7 MPa in a direction in which the ultraviolet light UV-irradiated surfaces come into close contact with each other, and this state was maintained for one hour. Thereafter, after the temperature of the entirety was reduced up to a room temperature, the above-mentioned pressing was stopped, and it was confirmed whether or not the substrates are bonded to each other. As a result, the substrates are firmly bonded to each other, and thus it was not possible to detach them from each other without damage.
Meanwhile, even when a resin base material constituted by a cycloolefin polymer (manufactured by Nippon Zeon Co., Ltd., ZEONEX480R, glass transition temperature of 138° C.) which is different from the above was used, and even when a resin base material constituted by polycarbonate (manufactured by Bayer AG, glass transition temperature of 210° C.) was used, the same results were obtained. In addition, even when the irradiation time of ultraviolet light UV was set to 5 minutes, the same results were obtained.
Finally, the microchip 101 after the bonding process P12 was irradiated with visible light VL that substantially includes light having a wavelength of a visible region from the light transmissive base material 2 side, by using a xenon lamp (manufactured by Asahi Spectra Co., Ltd., LAX-1000). The irradiation with visible light VL was performed in dry air. A distance between the lamp and the surface of the resin base material 1 and a distance between the lamp and the surface of the light transmissive base material 2 were set to 5 cm, irradiation intensity was set to 50 mW/cm2, and an irradiation time was set to 10 minutes. As other conditions, under conditions in which the irradiation intensity was set to 167 mW/cm2 and the irradiation time was set to 10 minutes, the above-mentioned irradiation was performed on another microchip sample.
In addition,
As shown in
As described above, in the method of manufacturing the microchip 101 of the present invention, the fluorescent molecules with a fluorescent property which are generated by ultraviolet light UV are in an excited state by irradiating the ultraviolet light UV-irradiated facing surface B4 of the resin base material 1 and the ultraviolet light UV-irradiated facing surface A4 of the light transmissive base material 2 with visible light VL, and electrons move to another polymer contained in each synthetic resin material, and thus the fluorescent molecules become nonfluorescent molecules. Thereby, the fluorescence of the microchip 101 can be reduced.
In addition, since the visible light VL substantially includes light having a wavelength of 380 nm to 800 nm which includes little ultraviolet light, the fluorescent molecules generated in the ultraviolet process P11 can be reliably used as nonfluorescent molecules without newly generating fluorescent molecules with a fluorescent property which are generated by irradiation with ultraviolet light UV. Thereby, the fluorescence of the microchip 101 can be further reduced.
In addition, the bonding process P12 is performed after the ultraviolet process P11, and the visible light process P13 of performing irradiation with visible light VL after the bonding process P12 is performed. Thus, the fluorescent molecules with a fluorescent property which are generated by ultraviolet light UV can be reliably used as nonfluorescent molecules, and the resin base material 1 and the light transmissive base material 2 can be reliably bonded to each other without decreasing the adhesion between the resin base material 1 and the light transmissive base material 2. Thereby, it is possible to further reduce the fluorescence of the microchip 101 and to create the microchip 101 that is excellent in pressure resistance, and the like.
In addition, since the resin base material is a cycloolefin polymer with low intrinsic fluorescence, the fluorescent molecules with a fluorescent property which are generated by ultraviolet light UV can be reliably used as nonfluorescent molecules. Thereby, the fluorescence of the microchip 101 can be further reduced.
The method of manufacturing the microchip 201 according to the second embodiment of the present invention includes the ultraviolet light process PU1 of irradiating the facing surfaces 94 before the pair of resin base materials are bonded to each other, with ultraviolet light UV, the visible light process PV2 of irradiating the ultraviolet light UV-irradiated facing surface 94 of the pair of resin base materials, with visible light VL, and the bonding process PA3 of bringing the facing surfaces 94 after the visible light process PV2 into contact with each other to thereby bond the pair of resin base materials to each other.
First, a first resin base material 11 and a second resin base material 21 which are a pair of resin base materials are prepared. The concave portion 3 serving as a fine flow channel is formed in one surface of the first resin base material 11, and the plurality of injection holes 16 for injection of a sample are formed in the second resin base material 21.
In addition, intensity, workability, adhesion between the resin base materials, and the like are considered for the first resin base material 11 and the second resin base material 21. A silicone resin such as a cycloolefin copolymer (COC), a cycloolefin polymer (COP), polymethyl methacrylate (PMMA), polycarbonate (PC), or polydimethylsiloxane (PDMS), or a material such as polythylene telephthalate (PET) or amorphous polyolefin is used as the first resin base material and the second resin base material. In particular, the cycloolefin copolymer (COC) and the cycloolefin polymer (COP) are suitably used because these polymers are synthetic resin materials with low intrinsic fluorescence.
Next, as shown in
Next, as shown in
Finally, after the visible light VL-irradiated first surface 14 including the concave portion 3 and the visible light VL-irradiated second surface 24 are caused to face each other, a rise in temperature is performed in a state where the first surface 14 and the second surface 24 are brought into contact with each other, thereby bonding the first resin base material 11 and the second resin base material 21 to each other (bonding process PA3). Accordingly, as shown in
Hereinafter, the second embodiment of the present invention will be described in more detail using Example 2. The present invention is not limited to the example below.
First, as the first resin base material 11 and the second resin base material 21, a pair of resin base materials (30 mm×30 mm, thickness of 1.5 mm) constituted by a cycloolefin copolymer (manufactured by Polyplastics Co., Ltd., TOPAS5013L-10, glass transition temperature of 134° C.) were used. The first resin base material 11 and the second resin base material 21 were created by injection molding using a mold for forming the concave portion 3 of the first resin base material 11 and the injection holes 16 of the second resin base material 21.
Next, each of the surfaces of the first surface 14 of the first resin base material 11 and the second surface 24 of the second resin base material 21 was irradiated with ultraviolet light UV (wavelength of 172 nm) by using an Xe excimer lamp (manufactured by Ushio Inc., UER20-172A). The irradiation with ultraviolet light UV was performed in a nitrogen atmosphere. A distance between the lamp and the surface of the first resin base material 11 and a distance between the lamp and the surface of the second resin base material 21 were set to 5 mm, irradiation intensity was set to 10 mW/cm2, and an irradiation time was set to 20 minutes. A surface to be irradiated with ultraviolet light UV was used as the entirety of each of bonding surfaces to be bonded.
Next, the first surface 14 of the first resin base material 11 which includes the concave portion 3 and the second surface 24 of the second resin base material 21 after the ultraviolet light process PU1 were irradiated with visible light VL that substantially includes light having a wavelength of a visible region, by using a xenon lamp (manufactured by Asahi Spectra Co., Ltd., LAX-1000). The irradiation with visible light VL is performed under dry air. A distance between the lamp and the surface of the first resin base material 11 and a distance between the lamp and the surface of the second resin base material 21 were set to 5 cm, irradiation intensity was set to 78 mW/cm2, and an irradiation time was set to 10 minutes. As other conditions, the irradiation with visible light VL was performed on another microchip sample in a nitrogen atmosphere. In addition, as the visible light VL, light of a visible region including a portion of ultraviolet light having a wavelength of equal to or less than 380 nm as shown in
Finally, the ultraviolet light UV-irradiated surfaces of the first resin base material 11 and the second resin base material 21 after the visible light process PV2 were caused to face each other and to come into contact with each other, and the temperature of the entirety was increased to 100° C. while performing pressing on the entirety with pressure of 0.7 MPa in a direction in which the ultraviolet light UV-irradiated surfaces come into close contact with each other, and this state was maintained for one hour. Thereafter, after the temperature of the entirety is reduced up to a room temperature, the above-mentioned pressing is stopped, and it is confirmed whether or not the resin base materials are bonded to each other. As a result, the resin base materials are firmly bonded to each other, and thus it is not possible to detach them from each other without damage.
As shown in
As described above, in the method of manufacturing the microchip 201 of the present invention, the fluorescent molecules with a fluorescent property which are generated by ultraviolet light UV are in an excited state by irradiating the ultraviolet light UV-irradiated first surface 14 of the first resin base material 11 and the ultraviolet light UV-irradiated second surface 24 of the second resin base material 21 with visible light VL, and electrons move to another polymer contained in each synthetic resin material, and thus the fluorescent molecules become nonfluorescent molecules. Thereby, the fluorescence of the microchip 201 can be reduced.
In addition, since the visible light VL substantially includes light having a wavelength of 380 nm to 800 nm, the fluorescent molecules generated in the ultraviolet light process PU1 can be reliably used as nonfluorescent molecules without newly generating fluorescent molecules with a fluorescent property which are generated by irradiation with ultraviolet light UV. Thereby, the fluorescence of the microchip 201 can be further reduced.
In addition, the visible light process PV2 is performed of irradiating the ultraviolet light UV-irradiated first surface 14 of the first resin base material 11 and the ultraviolet light UV-irradiated second surface 24 of the second resin base material 21 with visible light VL after the ultraviolet light process PU1, and the bonding process PA3 is performed after the visible light process PV2. Thus, the fluorescent molecules with a fluorescent property, which are generated by ultraviolet light UV, can be reliably used as nonfluorescent molecules. Thereby, the fluorescence of the microchip 201 can be further reduced.
In addition, since the resin base material is a cycloolefin copolymer (COC) with low intrinsic fluorescence, the fluorescent molecules with a fluorescent property, which are generated by ultraviolet light UV, can be reliably used as nonfluorescent molecules. Thereby, the fluorescence of the microchip 201 can be further reduced.
Meanwhile, the present invention is not limited to the above-mentioned embodiments. For example, the present invention can be modified and embodied as follows, and these embodiments are within the scope of the present invention.
In the above-mentioned first embodiment, although the concave portion 3 is formed in the resin base material 1 and the injection holes 16 are formed in the light transmissive base material 2, the injection holes 16 may be formed in the resin base material 1 and the concave portion 3 may be formed in the light transmissive base material 2. In addition, the concave portion 3 may be provided in both the resin base material 1 and the light transmissive base material 2. In addition, the concave portion 3 and the injection hole 16 may be provided in any one of the resin base material 1 and the light transmissive base material 2.
In Modified Example 2, a light transmissive base material is used as the first resin base material 31 and the second resin base material 41. Thereby, in the above-mentioned second embodiment, the first surface 14 including the concave portion 3 and the second surface 24 are irradiated with visible light VL in the visible light process PV2, as shown in
The present invention is not limited to the above-mentioned embodiments, but can be appropriately changed without departing from the scope of the present invention.
It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and alterations may occur depending on design requirements and other factors insofar as they are within the scope of the appended claims of the equivalents thereof.
Number | Date | Country | Kind |
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2010-271253 | Dec 2010 | JP | national |
Number | Date | Country | |
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Parent | PCT/JP2011/068512 | Aug 2011 | US |
Child | 13904273 | US |