The present invention relates to an affinity chromatography microdevice and a method for manufacturing the same.
A specific target material having biologic activity is selectively combined by affinity against a specific capture material, just like an enzyme-substrate reaction. The affinity chromatography separates and refines only target materials using the affinity. Specifically, a capture material that can be selectively combined with a desired target material is bonded with an insoluble support, thereby forming a complex. The complex is filled into a pipe and a reagent flows through the complex. As a result, only the target material that can be selectively combined with the capture material remains, while the materials having no affinity are eluted. Since the affinity chromatography separates and refine materials having biologic activity, many efforts have been made to develop bio-information sensing devices that can sense diseases simply and conveniently.
In bio-MEMS fields, many microfabricated temperature control devices have been introduced in association with PCR or thermal cycling. The temperature control devices must enhance thermal isolation around a reaction chamber in order for precise temperature control and must reduce thermal crosstalk between the reaction chambers or between the reaction chamber and a substrate where electronic components are integrated. The present inventors invented a microfabricated thermal cycling device, which is disclosed in Korean Patent Publication No. 10-0452946. In this patent, a silicon substrate is used as a bottom board and a bottom surface of the bottom board is etched to form the micro-fabricated thermal cycling device.
Although the micro-fabricated thermal cycling device can control temperature precisely, it is difficult to control the reaction between the target material and the capture material according to temperature.
Moreover, it is difficult to selectively separate and refine a plurality of biomaterials.
Technical Problem
It is, therefore, an object of the present invention to provide an affinity chromatography microdevice which can easily control the reaction between a target material and a capture material according to temperature, and a method for fabricating the same.
It is another object of the present invention to provide an affinity chromatography microdevice suitable for selectively separating and refining a plurality of biomaterials, and a method for fabricating the same.
Technical Solution
In accordance with one aspect of the present invention, there is provided an affinity chromatography microdevice including: a top board including an inlet and an outlet through which microfluid flows, and a reaction chamber for limiting the flow of the microfluid for reaction; and a bottom board including a microelectrode for independently controlling a micro-temperature, and a thermosensitive polymer matrix formed on the microelectrode, the thermosensitive polymer matrix being contracted or expanded according to temperature change. The thermosensitive polymer matrix may be a poly N-isopropylacrylamide (PNIPAAm). The PNIPAAm has a hydrophilic extended-chain structure below a predetermined temperature and forms a hydrophobic contracted-chain structure above the predetermined temperature. Therefore, the capture material can easily react with the target material above the predetermined temperature.
The bottom board may further include a surface treatment material such as a self assembled monolayer (SAM). Also, the bottom board may further include an immobilization material such as a dendrimer.
In accordance with another embodiment of the present invention, there is provided an affinity chromatography microdevice including: a top board including an inlet and an outlet through which microfluid flows, and a plurality of reaction chambers for limiting the flow of the microfluid for reaction; and a bottom board including a microelectrode array having a plurality of microelectrode for independently controlling a micro-temperature, and a thermosensitive polymer matrix formed on the microelectrode array, the thermosensitive polymer matrix being contracted or expanded according to temperature change.
In a further another aspect of the present invention, there is provided a method for manufacturing an affinity chromatography microdevice, including the steps of: a) preparing a bottom board including a microelectrode for independently controlling a micro-temperature, and a thermosensitive polymer matrix formed on the microelectrode, the thermosensitive polymer matrix being contracted or expanded according to temperature change; b) preparing a top board including a reaction chamber, an inlet, and an outlet; and c) attaching the bottom board to the top board.
The step a) may include the steps of: a1) forming a self assembled monolayer (SAM) on the microelectrode by processing 3,3-dithoiopropionic acid bis-N-hydroxysuccinimide ester (DTSP); a2) forming a dendrimer on the SAM by processing a dendrimer nanostructural solution; and a3) forming the thermosensitive polymer matrix on the dendrimer.
Advantageous Effects
According to the present invention, a thermosensitive polymer matrix is applied to an affinity chromatography microdevice having a good thermal interference reduction characteristic. Therefore, capture material and target material can be easily combined by controlling the temperature of a reaction chamber.
In addition, when a plurality of reaction chambers are arranged, a plurality of bio-materials can be selectively separated and refined.
The above and other objects and features of the present invention will become apparent from the following description of the preferred embodiments given in conjunction with the accompanying drawings, in which:
Other objects and aspects of the invention will become apparent from the following description of the embodiments with reference to the accompanying drawings, which is set forth hereinafter.
Referring to
The bottom board includes an insulating heating thin film 106a, a heater 102, a temperature sensor (104 in
The bottom board may include the insulating heating thin film 106a and an insulating layer 106b that are formed on top and bottom surfaces of a first substrate 100, respectively. The first substrate 100 is formed of plastic or silicon. The heater 102, the temperature sensor (104 in
A surface treatment material 121 may be provided on the microelectrode 110. An immobilization material 122 may be provided on the surface treatment material 121 in order to increase adsorption site between the PNIPAAm 123 and the capture material 124. The surface treatment material 121 includes SAM and the immobilization material 122 includes dendrimer.
The top board includes an inlet 114, a reaction chamber 118, and an outlet 120 on a second substrate 112 formed of silicon or plastic. Microfluid flows through the inlet 114, the reaction chamber 118, and the outlet 120. The inlet 114 is a portion where a solution is introduced, a passage 116 is a portion where the introduced solution moves, the reaction chamber 118 is a portion where the solution reacts, and the outlet 120 is a portion where the solution is discharged after the reaction.
The top board and the bottom board are bonded with each other. It is preferable that adhesive is applied on the bonded portion 130 in order to prevent the introduced solution from being discharged to the outside through the bonded portion 130.
Referring to
The second substrate 112 may be formed of at least one of polymer, metal, silicon, quartz, elastic material, ceramic, printed circuit board (PCB), and combination thereof. Examples of the polymer include polymethylmethacrylate (PMMA), polycarbonate (PC), cyclo olefin copolymer (COC), cyclo olefin polymer (COP), liquid crystalline polymers (LCP), polydimethylsiloxane (PDMS), polyamide (PA), polyethylene (PE), polyimide (PI), polypropylene (PP), polyphenylene ether (PPE), polystyrene (PS), polyoxymethylene (POM), polyetheretherketone (PEEK), polytetrafluoroethylene (PTFE), polyvinylchloride (PVC), polyvinylidene fluoride (PVDF), polybutyleneeterephthalate (PFA), fluorinated ethylenepropylene (FEP), and perfluoralkoxyalkane (PFA). Examples of the metal include aluminum, copper, and iron.
When the second substrate 112 is formed of plastic, evaporation of the reaction fluid occurs seriously at high temperature. In order to prevent this evaporation, a glass coating layer may be further formed on inner walls of the passage 116 and the reaction chamber 18.
As illustrated in
The insulating layer 108, the SAM 121, the dendrimer 122, the PNIPAAm 123, and the capture material 124 are not shown in
Referring to
The first substrate 100 may be formed of materials used for the second substrate 112 of the top board. Preferably, the first substrate 100 is formed of silicon or plastic. The insulating heating thin film 116a has a thickness of 0.1 to 10 μm and is formed of one selected from the group consisting of Si3N4, phosphosilicateglass (PSG), SiO2, and combination thereof, e.g., Si3N4/SiO2/Si3N4, SiO2/Si3N4/SiO2, and SiO2/Si3N4/SiO2/Si3N4, Si-added combination, e.g., Si/Si3N4, Si3N4/Si, Si/SiO2, SiO2/Si, Si/Si3N4/SiO2/Si3NN4, Si3N4/Si/SiO2/Si3N4, Si/SiO2/Si3N4/SiO, SiO2/Si/Si3N4/SiO2, Si/Si3N4/SiO2/Si3N4/SiO2, and Si/SiO2/Si3N4/SiO2/Si3N4, and polymer, e.g., polymethylmethacrylate (PMMA), polycarbonate (PC), cyclo olefin copolymer (COC), cyclo olefin polymer (COP), polyimide (PI), polystyrene (PS), polyvinylchloride (PVC), liquid crystalline polymers (LCP), and perfluoralkoxyalkane (PFA).
Referring to
A predetermined portion of the first substrate 100 is formed to expose the insulating heating thin film 106a. More specifically, the heater 102 is formed in the insulating heating thin film 106a, and a predetermined portion of the first substrate 100 under the heater 102 is removed. Then, the insulating layer 106b is formed on the bottom surface of the remaining first substrate 100. The reaction part of the affinity chromatography microdevice can be thermally isolated from the peripheral part effectively by the structure of the first substrate 100, the insulating heating thin film 106a, and the insulating layer 106b.
The insulating layer 108 is thick enough to cover the heater 102 and the temperature sensor 104, and may be formed of materials used for forming the insulting heating thin film 106a.
The bottom board includes the SAM 121, the dendrimer 122, the PNIPAAm 123, and the capture material 124, which are formed on the exposed microelectrode 110.
The microelectrode 110 may contain various chemicals, including surface active agent. It is preferable that the SAM 121 and the dendrimer 122 are contained as a building block for the effective immobilization of the target material. The dendrimer 122 has amine group on its surface and can be hydrated and immobilized by the reaction with the PNIPAAm 123.
The bottom board of
Referring to
The thermosensitive polymer matrix causes the rapid and reversible change of the hydration/dehydration in the solution dependently on the temperature. Therefore, the thermosensitive polymer matrix reacts sensitively to the slight temperature change around the LCST and changes reversibly. Because the structure of the thermosensitive polymer matrix is changed at the temperature that is easily adjusted, the change of molecules can be easily controlled at the outside.
Referring to
Referring to
Referring to
Referring to
Referring to
Referring to
Referring to
The PNIPAAm 123 is contracted and a large amount of Gox 126 is attached to the dendrimer 122. Thus, a large amount of the anti Gox Ig G 127 is immobilized. The fluorescent picture of the shape of the microelectrode 110 can be seen using the fluorescent beam 128 attached to the end of the anti Gox Ig G 127.
On the contrary, when the temperature is set below the LCST, the PNIPAAm 123 is extended and the Gox 126 is not almost immobilized on the dendrimer 122. Therefore, the anti Gox Ig G 127 also is not almost immobilized. The fluorescent picture cannot be seen.
Referring to
A second mask 704 for the passage 116 is formed on the bottom surface of the etched second substrate 112. The second substrate 704 is etched to a predetermined depth using the second mask 704. The passage 116 is formed narrowly. Therefore, the second substrate 112 is etched more thinly than the thickness etched in forming the reaction chamber 118. The second mask 704 can be formed by partially removing the first mask 702.
Referring to
Examples of the etching process include a sand blaster process and a laser ablation process.
Referring to
Referring to
Referring to
Referring to
Referring to
Referring to
Referring to
Referring to
Specifically, the surface of the microelectrode 110 is cleaned using piranha solution or distilled water. The SAM 121 is formed by flowing 5 mM DTSP(3,3-dithiopropionic acid bis-N-hydroxysuccinimide ester), which is dissolved in DMSO, over the microelectrode 110. The DTSP can expose a reactive residue that is easily adsorbed with the surface of the microelectrode 110 and has a good reactivity with respect to amine radical existing on the molecule surface of the dendrimer 122. Thus, the DTSP is used as a reagent. A remaining reagent is removed by cleaning the microelectrode 110 using DMSO and ethanol. A dendrimer nanostructural solution (0.5%, w/w) diluted with ethanol flows over the surface activated by the SAM 121. The dendrimer nanostructure forms a covalent bond with the surface of the SAM 121 and thus is stably immobilized. Consequently, the immobilized dendrimer 122 is formed. The PNIPAAm 123 as the thermosensitive polymer is formed in the dendrimer 122. In this embodiment, PNIPAAm-NHS is used as the PNIPAAm 123. The PNIPAAm-NHS is prepared by substituting hydroxysuccinimide (NHS) for one end of the polymer. The PNIPAAm-NHS can be checked using nuclear magnetic resonance (NMR) spectrometry. It can be checked using FT-IR spectrometry that the PNIPAAm-NHS can form the surface of the thermosensitive polymer. The PNIPAAm 123 is immobilized on the dendrimer 122 by reaction between the activated surface of the dendrimer 122 and the PNIPAAm-NHS. The capture material 124 is formed on the activated surface of the remaining dendrimer 122. The capture material 124 contains amine group and can be chemically immobilized using the amine reaction radical remaining in the dendrimer 122 as the target.
Referring to
Referring to
A top substrate of the affinity chromatography microdevice includes a plurality of reaction chambers 118A so that a plurality of capture materials can react with a plurality of target materials. Only one inlet and only one outlet are formed. The inlet and the outlet of
A bottom board of the affinity chromatography microdevice includes microelectrode arrays 110a, 110b and 110c and thermosensitive polymer matrix. In the microelectrode arrays 110a, 110b and 110c, microelectrodes that can independently control temperature are arranged. The thermosensitive polymer matrix is formed on the microelectrode arrays 110a, 110b and 110c and are contracted or expanded according to the temperature change. Also, the bottom board includes heaters 102a, 102b and 102c and temperature sensors. The heaters 102a, 102b and 102c heat the reaction chambers 118a, 118b and 118c in order to independently control the temperatures of the microelectrode arrays. The temperature sensors sense the temperatures.
Further, the bottom board includes SAMs and dendrimers on the microelectrode arrays 110a, 110b and 110c. The SAMs and the dendrimers are used as the surface treatment material and the immobilization material, respectively. PNIPAAm can be used as the thermosensitive polymer matrix.
As described above, when the solution containing a plurality of target materials through the common inlet, the plurality of target materials can be separated and refined by different capture materials formed on the microelectrode arrays 110a, 110b and 110c.
In addition, the temperature can be independently controlled at the reaction chambers 118a, 118b and 118c. Therefore, the bonding of the capture materials and the target materials can be freely controlled through the temperature control. The affinity chromatography microdevice in accordance with the present invention is suitable for selectively separating and refining a plurality of biomaterials.
The present application contains subject matter related to Korean patent application No. 2005-115897 and 2006-55481, filed in the Korean Intellectual Property Office on Nov. 30, 2005, and Jun. 20, 2006, respectively, the entire contents of which is incorporated herein by reference.
While the present invention has been described with respect to certain preferred embodiments, it will be apparent to those skilled in the art that various changes and modifications may be made without departing from the scope of the invention as defined in the following claims.
Number | Date | Country | Kind |
---|---|---|---|
10-2005-0115897 | Nov 2005 | KR | national |
10-2006-0055481 | Jun 2006 | KR | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
---|---|---|---|---|
PCT/KR2006/005022 | 11/27/2006 | WO | 00 | 5/23/2008 |