WO2013154213A1

WO2013154213A1 - Diagnostic cartridge

Info

Publication number: WO2013154213A1
Application number: PCT/KR2012/002722
Authority: WO
Inventors: Kwangsuk YANG; Hyekyung JEON; Gueisam Lim; Jungsun Han
Original assignee: Lg Electronics Inc.
Priority date: 2012-04-10
Filing date: 2012-04-10
Publication date: 2013-10-17

Abstract

The present invention relates to a diagnostic cartridge including: an injection part adapted to inject a biological sample and a reactant thereinto; a micro flow passage adapted to move the injected biological sample and reactant from the injection part therealong; and a detector adapted to detect the reaction result of the biological sample and reactant moved along the micro flow passage, wherein the micro flow passage is formed in such a manner where a plurality of micro flow passages having small widths and a plurality of micro flow passages having large widths are connected to each other in an alternating manner, so that the air bubbles generated in a microfluidic system can be removed and the gentle mixing of fluids like samples can be accelerated, thereby enhancing the reliability of the measured signal and obtaining reproducible measured results.

Description

DIAGNOSTIC CARTRIDGE

The present invention relates to a diagnostic cartridge having a structure wherein air bubbles are removed and mixing is accelerated, and more particularly, to a diagnostic cartridge that is provided with a micro flow passage through which air bubbles can be removed and the mixing of samples can be accelerated.

With the advancement of biosensor technology and semiconductor technology, recently, the development and application for the micro fluid control technology controlling the flow, flow rate, or flowing direction of a micro fluid have been accelerated. According to such micro fluid control technology, the specific components contained in a biological fluid like blood are detected quantitatively or qualitatively. Therefore, the technology is recognized as one of main technology in the fields of a biochip or lab-on-a-chip (LOC).

On the other hand, it is desirable that a diagnostic cartridge should not have any air bubbles while fluids are being moved. Except that the generation of the air bubbles is intendedly needed, the diagnostic cartridge possibly suppresses the generation of air bubbles to permit the flow of the fluids to be constantly adjusted. However, recently, commercial diagnostic cartridges should conduct a biochemical reaction using a small quantity of biological sample and a mixing process for accelerating the biochemical reaction. So as to perform the unit operation in a single cartridge, air bubbles are unavoidably formed while the samples are being moved.

The formation of the air bubbles causes the residual pressure in the interiors of microfluidic channels during the samples are moved or mixed and further interferes with a gentle reaction between an object substance in the sample and an electrode, the antibody on the electrode, or the antibody fixed on a surface.

Accordingly, the present invention has been made in view of the above-mentioned problems occurring in the prior art, and it is an object of the present invention to provide a diagnostic cartridge that can remove the air bubbles generated in a microfluidic system and accelerate the gentle mixing of fluids like samples, thereby enhancing the reliability of the measured signal and obtaining reproducible measured results.

To accomplish the above object, according to the present invention, there is provided a diagnostic cartridge including: an injection part adapted to inject a biological sample and a reactant thereinto; a micro flow passage adapted to move the injected biological sample and reactant from the injection part therealong; and a detector adapted to detect the reaction result of the biological sample and reactant moved along the micro flow passage, wherein the micro flow passage is formed in such a manner where a plurality of micro flow passages having small widths and a plurality of micro flow passages having large widths are connected to each other in an alternating manner.

According to the present invention, desirably, the micro flow passage is bent at the portions where the plurality of micro flow passages having large widths are connected to the plurality of micro flow passages having small widths.

According to the present invention, desirably, the plurality of micro flow passages having small widths connected to the bent plurality of micro flow passages having large widths are disposed in parallel to each other.

According to the present invention, desirably, the diagnostic cartridge further includes a moving part adapted to move the injected biological sample and reactant.

According to the present invention, desirably, the moving part pushes or sucks the air in the micro flow passage to move the injected biological sample and reactant.

According to the present invention, desirably, the plurality of micro flow passages having large widths are rounded on the outside thereof.

According to the present invention, desirably, the plurality of micro flow passages having large widths catch the air bubbles generated while the injected biological sample and reactant are being moved.

According to the present invention, desirably, the plurality of micro flow passages having large widths make the moving speeds of the injected biological sample and reactant different from each other, thereby raising their mixing ratio.

According to the present invention, the diagnostic cartridge can remove the air bubbles generated in a microfluidic system and accelerate the gentle mixing of the fluids like samples, thereby enhancing the reliability of the measured signal and obtaining reproducible measured results.

FIG.1 is a view showing a configuration of a diagnostic cartridge according to a preferred embodiment of the present invention.

FIG.2 is a view showing an effect of the micro flow passage in the diagnostic cartridge according to the preferred embodiment of the present invention.

FIGS.3 and 4 are views showing other effects of the micro flow passage in the diagnostic cartridge according to the preferred embodiment of the present invention.

FIGS.5 to 7 are views showing configurations of diagnostic cartridges according to various embodiments of the present invention.

The present invention should not be limited to the preferred embodiment described below, but may be modified in various forms without departing the spirit of the invention. Therefore, the various embodiments of the invention will be in detail explained with reference to the attached drawings. However, it should be understood that the invention is not limited to the preferred embodiment of the present invention, and many changes, variations and modifications of the constructional details illustrated and described may be resorted to without departing from the spirit of the invention.

The terms such as ordinal numerals (first, second, and the like) are used to explain a variety of components, but the components are not defined as the terms. That is, the terms are used just to distinguish one component from other components.

If it is expressed that a component is “connected” or “coupled” to another component, it should be understood that the component is connected or coupled to another component, and alternatively, another component is interposed between the connected or coupled two components. Therefore, the terms used in the description does not define the present invention, but are defined as the concepts conforming to the technical spirit of the invention on the basis where the terms are appropriately defined to explain the invention best.

A singular expression includes a plural expression if there is no difference between them in the context. In the description of the invention, the terms such as “includes” or “comprises” are used to define the existence of features, numbers, steps, operations, components, parts, or their combinations, and to further include the possibility of one or more features, numbers, steps, operations, components, parts, or their combinations.

In the description of the invention with reference to the attached drawings, further, the same components are indicated by the same reference numerals as each other, and for the brevity of the description, the explanation on their repeated features will be avoided. If it is determined that the detailed description on the known technology related to the invention makes the spirit of the invention unclear, it will be also avoided.

FIG.1 is a view showing a configuration of a diagnostic cartridge according to a preferred embodiment of the present invention. In more detail, the portion shown in FIG.1 shows the configuration of a fluid channel, that is, a micro flow passage in the diagnostic cartridge, through which a fluid is passed to move.

As shown in FIG.1, the diagnostic cartridge according to the present invention includes an injection part (not shown) into which a biological sample and a reactant are injected. In this case, the biological sample and the reactant are at the same time injected into one injection part (not shown), and alternatively, they are injected respectively into two different injection parts (not shown).

A micro flow passage 100 is formed by connecting micro flow passages having different widths to each other in an alternating manner. That is, as shown in FIG.1, micro flow passages 110-1, 110-2, 110-3, 110-4, and 110-5 having small widths and micro flow passages 120-1, 120-2, 120-3, and 120-4 having large widths are connected alternately to each other.

The injected substances are first moved in the order of the micro flow passage 110-1 having small width, the micro flow passage 120-1 having large width, the micro flow passage 110-2 having small width, the micro flow passage 120-2 having large width, and the like. At this time, the micro flow passages 120-1, 120-2, 120-3, and 120-4 having large widths are bent to make the moving directions changed. Also, the micro flow passages 110-1, 110-2, 110-3, 110-4, and 110-5 having small widths are disposed in parallel to each other.

On the other hand, the diagnostic cartridge according to the present invention further includes a detector (not shown) adapted to detect the reaction result of at least one of the biological sample and reactant moved along the micro flow passage 100. If an optical method is applied, the detector is composed of an LED (Light Emitting Diode) or PD (Photo Detector), and if a method of physical chemistry is applied, it is composed of an electrode.

First effect of micro flow passage: removal of air bubbles

FIG.2 is a view showing an effect of the micro flow passage in the diagnostic cartridge according to the preferred embodiment of the present invention. In more detail, FIG.2 is an enlarged view of FIG.1, wherein the micro flow passage 110-1 having small width is connected to the micro flow passage 120-1 having large width and air bubbles 10 generated from the injection of liquid (fluid) are shown by circles.

In a microfluidic system, as shown in FIG.2, while the liquid (fluid) is being moved, the air bubbles 10 are generated. As mentioned above, also, the generation of the air bubbles causes many troubles like measurement errors.

In case of the configuration of the present invention wherein the plurality of micro flow passages having small widths and a plurality of micro flow passages having large widths are connected to each other in an alternating manner, the air bubbles 10 are caught by the plurality of micro flow passages having large widths. That is, if the air bubbles 10 are generated, they are moved along the micro flow passage 110-1 having small width, but when they reach the micro flow passage 120-1 having large width, it is difficult to be moved to the micro flow passage 110-2 having small width.

Even though some of the air bubbles 10 are moved to the micro flow passage 110-2 having small width, they are passed through the micro flow passage 120-2 having large width, and after that, the air bubbles 10 are almost removed. At this time, the micro flow passages 110-1, 110-2,… having small widths desirably have smaller widths than the diameters of the air bubbles 10, but even when they have larger widths than the diameters of the air bubbles 10, the air bubbles 10 are effectively removed through a plurality of steps, so that no air bubbles are contained in the liquid (fluid) discharged finally.

The detector serves to analyze the liquid (fluid) from which the air bubbles 10 are removed, thereby providing more precise results.

Second effect of micro flow passage: acceleration of mixing and reaction speeds

FIGS.3 and 4 are views showing other effects of the micro flow passage in the diagnostic cartridge according to the preferred embodiment of the present invention. The configuration of the micro flow passage 100 of FIG.3 is basically the same as in FIG.1, and FIG.4 is an enlarged view of the micro flow passage having large width in the whole configuration of the micro flow passage 100 of FIG.3. The arrows of FIGS.3 and 4 indicate the routes along which a first solution 20 and a second solution 30 flow.

As shown in FIG.3, if two solutions flow along the micro flow passage having small width, the mixing process through capillary movement is carried out because of the small width of the micro flow passage. That is, the physical distances between molecules are substantially short to allow their mixing to be easily conducted.

On the other hand, if the solutions enter the micro flow passage having large width, the first solution 20 is moved along the outside of the micro flow passage with large width and the second solution is moved to the inside thereof.

FIG.4 shows the movements of the two solutions in a clear manner. At this time, the length of the outside of the micro flow passage having large width is longer than that of the inside thereof. As shown in FIG.4, if it is assumed that the inside length thereof is 3mm, the outside length thereof is 6.7mm because it is turned along the curved line thereof. Therefore, the ratio of the outside length to the inside length is 1:2.3, which makes the outside length longer by about 2.3 times than the inside length. Like this, the mixing of the two solutions is accelerated through the difference of the moving distances thereof.

Further, if the solutions enter the micro flow passage having small width again, the first solution 20 and the second solution 30, which exist before and after the moving distance of about 2.3 times, become close to each other up to a distance of 100um, that is, the width of the micro flow passage having small width, thereby minimizing the distance required for their diffusion. That is, when the two solutions are moved along the micro flow passage having small width and then enter the micro flow passage having large width again, if the width of the micro flow passage having small width is only about 100um, the two solutions are diffused within a relatively narrow range to reduce the distance required for their diffusion.

According to the present invention, the structure of the micro flow passage 100 of the diagnostic cartridge allows the mixing and diffusion of the solutions to be easily conducted. In more detail, the widths of the micro flow passage 100 are adjusted large and small to optimize the mixing effect of the solutions, thereby advantageously enhancing the reaction speed of different liquids (fluids).

On the other hand, the numeric values as mentioned above are used just to describe the preferred embodiment of the present invention, but they may be varied, without any limitation thereto. The micro flow passages having large widths may have the widths in a range between 0.1mm and 10mm, and in the same manner as above, the micro flow passages having small widths may have the widths in a range between 10um and 500um. That is, only if there is a difference between the widths of the micro flow passages having large widths and the widths of the micro flow passages having small widths, all of numeric values do not matter.

FIG.5 shows another embodiment of the present invention wherein the micro flow passages having small widths are short in length and the micro flow passages having large widths have more rounded shapes than those in FIG.1. In this embodiment where the micro flow passages having large widths are more occupied in area, the mixing effect can be more optimized.

FIG.6 shows still another embodiment of the present invention, which is similar to FIG.5, wherein the micro flow passages having small widths are more bent than those in FIG.5. In this embodiment where the micro flow passages having small widths are more complicated in structure, the mixing effect can be more optimized like FIG.5.

FIG.7 shows yet another embodiment of the present invention wherein the micro flow passages having small widths scarcely exist in shape and the micro flow passages having large widths mainly exist. In this embodiment, the effect of removing air bubbles can be best optimized.

As mentioned above, the diagnostic cartridge according to the preferred embodiments of the present invention can remove the air bubbles generated in the microfluidic system and accelerate the gentle mixing of the solutions like samples, thereby enhancing the reliability of the measured signal and obtaining reproducible measured results. In more detail, the effect of removing the air bubbles, which is mentioned in FIG.2, and the effect of accelerating the mixing and reacting speeds, which is mentioned in FIGS.3 and 4, are all provided to obtain more precise measurement results.

While the present invention has been described with reference to the particular illustrative embodiments, it is not to be restricted by the embodiments but only by the appended claims. It is to be appreciated that those skilled in the art can change or modify the embodiments without departing from the scope and spirit of the present invention.

Claims

A diagnostic cartridge comprising:

an injection part adapted to inject a biological sample and a reactant thereinto;

a micro flow passage adapted to move the injected biological sample and reactant from the injection part therealong; and

a detector adapted to detect the reaction result of the biological sample and reactant moved along the micro flow passage,

wherein the micro flow passage is formed in such a manner where a plurality of micro flow passages having small widths and a plurality of micro flow passages having large widths are connected to each other in an alternating manner.
The diagnostic cartridge according to claim 1, wherein the micro flow passage is bent at the portions where the plurality of micro flow passages having large widths are connected to the plurality of micro flow passages having small widths.
The diagnostic cartridge according to claim 2, wherein the plurality of micro flow passages having small widths connected to the bent plurality of micro flow passages having large widths are disposed in parallel to each other.
The diagnostic cartridge according to claim 1, further comprising a moving part adapted to move the injected biological sample and reactant.
The diagnostic cartridge according to claim 4, wherein the moving part pushes or sucks the air in the micro flow passage to move the injected biological sample and reactant.
The diagnostic cartridge according to claim 1, wherein the plurality of micro flow passages having large widths are rounded on the outside thereof.
The diagnostic cartridge according to claim 1, wherein the plurality of micro flow passages having large widths catch the air bubbles generated while the injected biological sample and reactant are being moved.
The diagnostic cartridge according to claim 1, wherein the plurality of micro flow passages having large widths make the moving speeds of the injected biological sample and reactant different from each other, thereby raising their mixing ratio.