KR100442412B1 - Lab on a chip system connected by capillaries - Google Patents

Abstract

The present invention relates to a lab-on-a-chip system developed to perform an integrated function by connecting two or more module-type lab-on-a-chip with a capillary tube according to the purpose, the system according to the present invention, for sample reaction, injection By preparing each of the lab, chip and lab lab-on-a-chip chips in the form of a module, and combining them according to the application, it is necessary to manufacture and experiment the chip compared to manufacturing an integrated system that includes all functions in one lab-on-a-chip. There is an advantage that the time and cost can be significantly reduced, and by changing the type of capillary tube, various separation methods used in capillary electrophoresis can be used.

Description

LAB ON A CHIP SYSTEM CONNECTED BY CAPILLARIES}

The present invention relates to a lab-on-a-chip system developed to perform an integrated function by connecting two or more modular lab-on-a-chips with capillary tubes. The system according to the present invention is a combination of each function of the on-chip of the module form of the capillary by combining the capillary tube, compared to the integrated system that contains all the functions in one lab-on-a-chip compared to the chip manufacturing and experiment The time and cost required can be greatly reduced, and the different types of capillaries can be easily used for various analysis systems.

Lab-on-a-Chip is a chemical microprocessor that integrates multiple devices onto a substrate of several cm2 size made of glass, silicon, or plastic using micromachining techniques such as photolithography technology used in semiconductor manufacturing processes. As such, high speed, high efficiency, low cost automated experiments are possible (see Kovacs, Anal. Chem. 68 (1996) 407A-412A).

Lab-on-a-chip analysis systems are based on the separation and analysis of capillary electrophoresis using capillary electroosmotic phenomena, the majority of which apply a voltage across a channel filled with a solution to create a flow of solution. Thus, the system is small in size compared to conventional commercial analyzers because it can perform solution movement and sample separation within the microchannels inside the lab-on-a-chip without using mechanical pumps or valves. The advantage is that the price is relatively low. In addition, the process of solution transfer, sample reaction, injection, separation, and detection can be carried out continuously by integrating a single lab-on-a-chip (Harrison, Science 261 (1993) 895-897), Dolnik, Electrophoresis 21 (2000) 41-54).

In addition, the lab-on-a-chip analysis system can accommodate all the modes of operation used in capillary electrophoresis. That is, capillary zone electrophoresis (CZE), which separates according to the amount of charge and size of the material by using a hollow channel, and adds a surfactant having a concentration greater than that to form micelles in the buffer solution. The material to be analyzed is filled with a packing material inside the capillary, such as micellar electrokinetic chromatography (MEKC), a column of liquid chromatography or gas chromatography, which can separate not only neutral substances but also neutral substances. Capillary electrochromatography (CEC) separated by distribution and capillary gel electrophoresis to separate macromolecules of high molecular weight, such as DNA and proteins, by filling a capillary polymer into a capillary Small size in the form of lab-on-a-chip It can be used in both systems.

As described above, the lab-on-a-chip analysis system has a simple system, and all processes necessary for analysis, such as solution movement, sample reaction, injection, separation, and detection, can be performed in one chip. It also has the advantage of being able to be used in various research fields because various analysis methods can be used. On the other hand, there is a disadvantage that chip design, fabrication and performance test must be performed for each analysis purpose except for general forms. For example, if you have designed an optimal system for the reaction, injection, separation, and detection that is most appropriate for the particular sample you want to analyze, then this analysis system can rarely be used except for the analysis of that particular sample. Therefore, when the types of samples to be analyzed are different and the analysis methods are different, the system has to be designed and manufactured for each sample, and the analysis system must be replaced as needed. In addition, various separation methods such as CZE, MEKC, CEC and CGE also have a problem in that only one separation method can be applied to one chip.

In order to solve these problems, the inventors separately fabricate lab-on-a-chips that can perform each process necessary for the analysis of materials for each module, and then integrate each module chip using a capillary tube according to the purpose of analysis. We have developed an analysis system in the form of a lab-on-a-chip.

1 is a plan view of various lab-on-a-chip in the form of a module,

2 is a cross-sectional view of a lab-on-a-chip system in which component modules are connected by capillaries;

3 is a view showing the configuration and operation of the analysis system,

Figure 4 is a graph of separation performance before and after passing the sample through the capillary connection type lab-on-a-chip system according to the present invention.

In order to achieve the above object, the present invention provides a lab-on-a-chip system in which each module-type lab-on-a-chip performing a reaction, separation and detection function of a sample is connected by a capillary tube.

Hereinafter, the present invention will be described in more detail.

The present invention can be easily and quickly applied to various fields of analysis by preparing each lab-on-a-chip that performs the reaction, separation, and detection functions of a sample in a module form and then combining them according to an analysis purpose using a capillary tube. And a capillary connected lab-on-a-chip system.

Hereinafter, the present invention will be described in more detail with reference to the drawings.

1 illustrates a plan view of representative modular lab-on-a-chips, and other various lab-on-a-chips may be used. In Figure 1, ① is a pre-column reactor for the reaction of the sample and the chip for injection, ② is a sample injection chip when the sample reaction is not required, ③, ④ is a separation lab on chip, ③ is separated It is a linear separation channel of about 0.01 mm to 20 cm in length. If the type of material to be analyzed is small or the material is well separated, a short channel can be used. Otherwise, a long channel can be used. Is a curved channel with a long separation channel of about 20 to 500 cm in length and can be used when analyzing a sample having a large number of analysis samples and poor separation. In Figure 1, ⑤, ⑥ is a detection wrap-on chip, ⑤ is for absorbance detection, ⑥ is a chip for electrochemical detection. Fluorescence detection can be performed directly at the channel end of the separation chip, so a separate detection chip is not required.

The channel width of each of the lab-on-a-chips as shown in FIG. 1 is about 0.01 μm to 10 cm, and the depth is about 0.01 μm to 1 cm. In each chip shown, the large circle drawn at the end of the channel means the container that can hold the solution, and the small circle means the capillary connection site.

Modules of the module type as shown in Figure 1 can be produced by engraving the channel on a plate of a material capable of channel processing, such as glass, quartz or fused silica material and plastic according to a conventional method. For example, to make channels in glass, quartz, or fused silica plates, they can be fabricated using photolithography, chemical etching, and molding, stamping, machining, and laser processing. You can engrave the channel you want. Plastic materials can be used such as PDMS (polydimethylsiloxane), PMMA (polymethylmethacrylate), PC (polycarbonate), PE (polyethylene), PP (polypropylene), PS (polystyrene), etc. For example, a method of making a channel in a plastic plate may be a molding technique such as pouring a mold and then solidifying it, or a hot embossing method, which is produced by pressing a flat substrate into a heated mold, or by mechanical means or light or heat. It is possible to use a method for processing using.

According to the present invention, a capillary connection type wrap-on-a-chip module according to the present invention can be manufactured by covering the channel with another substrate having a structure in which a connection hole is drilled so as to be connected to the substrate engraved with a channel as described above.

Each modular chip of capillary connection type can be combined to meet the purpose of analysis, and cut into 1-100 cm length of capillary in the hole of the plastic tube to insert the plastic tube of each chip to complete the system.

Capillary tube used in the connection of each module in the present invention may be made of a material such as quartz, fused silica, glass, polymer.

Capillary-connected analysis system according to the present invention is easy, quick and easy to connect and dismantle, compared to the integrated lab-on-a-chip with all the functions on one chip, it is easy to manufacture, can be manufactured at a low cost, and has a wide range of applications. have.

Also, when connecting each module chip with a capillary tube, polymer materials such as a capillary tube filled with a hollow material, a capillary tube filled with a filling material of several nm to several millimeters, and a gel may be used according to various separation methods such as CZE, MEKC, CEC and CGE. Filled capillary and capillary with the inner wall of the capillary can be used, so multiple separation methods can be applied with one chip.

The filling material inside the capillary and the material surface-treated on the inner wall can be a substance which can perform a series of physical, chemical and biological reactions with the analyte such as adsorption, absorption, ion exchange, etc. The gel may be a polymer material capable of forming a mesh structure therein such as agarose, polyacrylamide, cellulose, and the like.

Examples of the present invention are presented below, but the scope of the present invention is not limited by the examples.

Example 1 Fabrication and Connection of Capillary Connected Lab-on-a-Chip Module

Plastic chip modules were manufactured by molding using PDMS as follows.

First, a channel-engraved bottom plate (1 in Fig. 2) was coated with SU-8, a negative photoresist, on a silicon wafer at a height of 0.01 μm to 1 cm and covered with a photomask to be exposed to ultraviolet rays. Developing the wafer yields an embossed mold with the desired pattern. PDMS is poured onto the mold, cross-linked and then removed to obtain a PDMS plate with the desired engraved pattern.

In order to connect the completed chip modules to each other by a capillary tube, the channel cover plate of the substrate having the channel manufactured as described above should be manufactured in a structure capable of capillary connection, and thus manufactured using a silicon wafer without a pattern as follows. It was.

Referring to FIG. 2, a hole is made in a piece of PDMS having a size of several mm 2, and a plastic tube ② is inserted into this hole, and then into the hole of the plastic tube, the outer diameter is the same as the hole of the plastic tube, and the inner diameter is inscribed in the bottom plate ①. After inserting a capillary tube 3 of similar width, the PDMS piece was adhered to the silicon wafer without a pattern. PDMS was poured into this, crosslinked and then removed, and the plate was then drilled at the same position as the ends of the base plate channels and surface-treated with an arc discharge formed using Tesla coils.

Subsequently, the position of the end of the channel engraved on the lower plate ① and the capillary inner diameter inserted into the cover plate ④ are precisely aligned using a microscope, and the two plates are closely bonded to each other. Finally, the 200 μl pipette tip ⑤ is cut to an appropriate size. It fits tightly into the hole and fixed with adhesive to complete the module-type wrap-on-a-chip.

Example 2: Lab-on-a-chip System Configuration and Operation

For example, as shown in Figure 3, the chip (1) for sample injection and separation and the chip (2) for sample separation and laser-induced fluorescence detection was connected using a capillary tube (3) to configure the entire system for analysis.

A high voltage supply ④, a voltage divider ⑤ and a high voltage relay ⑥ were used to perform sample transfer, sample injection and separation on the chip using an electrical osmotic flow. Sample injection was performed using an open-close injection method, and the voltage applied to each container was controlled using a voltage divider. Before sample injection, voltage in the range of 0.1 kV to 50 kV in the sample container ⑦, 0.1 to 5 times the voltage applied to the sample container ⑦ in the buffer container ⑧, 0 to 1 times the voltage in the sample discharge container ⑨, and the buffer solution discharge A voltage of 0 V is applied to the container ,, and when the sample is injected, the high voltage relay ⑥ is used to cut off the voltage applied to the buffer container ⑧ for a predetermined time, for example, 0.01 seconds to 60 minutes, and then reconnect the sample. It was allowed to be injected into the channel. The injected sample is separated through the separation channel, and the detection of the sample concentrates the light source from the laser beam at the end of the separation channel, and collects the fluorescence generated from the sample with the fluorescent label through the filter through the objective lens. The intensity of fluorescence was measured with a photomultiplier tube detector. The computer 를 used to regulate the voltage of the high voltage supply and the high voltage relay and also to record and store the signal from the photomultiplier detector.

Example 3 Performance Test of a Lab-on-A-Chip System Connected by Capillary Tubes

After connecting the lab-on-a-chip for sample injection and the lab-on-a-chip for separation as shown in FIG. 3 with a capillary tube, fluorosein isothiocyanate (FITC) and fluoro to determine the presence of dead volume at the capillary connection site After injecting the mixed mixture, the materials separated before 5 mm after the capillary passage and 5 mm after the capillary passage were detected by laser-induced fluorescence detection to measure the theoretical numbers of the respective materials. The results are shown in FIGS. 4A and 4B and Table 1, respectively.

Before passing the capillary After passing capillary tube Analyte FITC Fluorosane FITC Fluorosane Travel time (seconds) 22.1 30.5 138.1 186.8 Theoretical singular (N) 1,090 1,100 2,400 2,100

The presence of dead volume at the junction leads to band widening, which reduces the theoretical number of each peak. As shown in the results of Table 1, no decrease in the theoretical number is observed, and the theoretical number increases as the separation length increases. It can be seen that there is no dead volume at the capillary connection.

According to the present invention, a lab-on-a-chip system developed to perform an integrated function by connecting two or more module-type lab-on-a-chips in a capillary tube according to a use includes a sample reaction, injection, separation, and detection lab. If each of the on-chips are manufactured in the form of modules and then combined with capillaries according to the purpose, the time and cost of chip manufacturing and experimentation can be reduced compared to manufacturing an integrated system including all functions in one lab-on-a-chip. By greatly changing the type of capillary tube, various separation methods used in capillary electrophoresis, such as capillary zone electrophoresis (CZE), micellar electrokinetic chromatography (MEKC), and capillary electrochromatography ( CEC), capillary gel electrophoresis (CGE), and the like.

The present invention is a system that can easily and quickly apply a variety of analytical methods can be widely used in the environment, pharmaceuticals, food and life research fields that require a variety of analytical techniques and equipment, and greatly reduces the time, expense and labor required for research It is expected that the efficiency of research can be dramatically increased by saving.

Claims (8)

Each modular lab-on-a-chip that performs the reaction, separation and detection of the sample has a structure connected by capillaries, wherein the capillaries are hollow, filled with fillers or polymer materials, or surface-treated with inner walls. Capillary connection lab on a chip system, characterized in that made of glass, quartz, fused silica or plastics material. delete The method of claim 1, Lab-on-a-chip system, characterized in that the material filled in the capillary tube or the material treated on the inner wall is capable of a physical, chemical or biological reaction with the material to be analyzed. The method of claim 1, A lab-on-a-chip system, characterized in that the polymeric material filled in the capillary is agarose, polyacrylamide or cellulose. delete The method of claim 1, Lab-on-a-chip system, characterized in that the module is made of glass, quartz, fused silica or plastic material. The method of claim 6, A lab-on-a-chip system, wherein the module is made of glass, quartz, or fused silica material and is manufactured by photolithography, chemical etching, molding, stamping, machining or laser processing. The method of claim 6, A wrap-on-a-chip system, wherein the module is a plastic material and is manufactured by molding, stamping, machining or laser processing.