Portable biochip having integrated structure for point-of-care testing

Abstract

The present invention relates to a portable biochip having an integrated structure for point-of-care diagnosis and, specifically, to a portable biochip having a novel structure and material, in which a specimen sample is introduced through an inlet (100), and then is primarily separated through a first filter part (200) using a porous structure, and the sample transferred through a bridge-shaped (∩) connection leg part (300) is secondarily separated by a second filter part (400), and then the degree of discoloration or color development of a reagent can be observed using a detection window (600) by means of a rectangular pattern film part (500) designed with a plurality of detection reagent chambers.

Description

A portable biochip with an integrated structure for field testing

[0001] The present invention relates to a portable biochip having an integrated structure for on-site diagnosis, and more particularly, to a portable biochip having a novel structure and material, wherein a specimen sample is introduced through an inlet, first separated through a first filter section using a porous structure, and then the sample is transported through a bridge-shaped (∩) connecting bridge section, and then secondarily separated through a second filter section, and then a detection window capable of observing discoloration or the degree of color development of a reagent is included through a rectangular type pattern film section in which a plurality of detection reagent chambers are designed.

[0002] With the advancement of science and technology and the growing interest in quality of life, the importance of diagnosing and preventing human diseases is growing day by day. The need for blood tests, in particular, to diagnose and analyze human diseases is growing.

[0003] Blood circulates throughout the body and passes through various organs, containing important information about the body's health. Therefore, various blood test techniques utilizing blood have been developed and are recognized as an essential item for health checkups.

[0004] The recent trend in blood testing technology is moving away from hospitals requiring blood samples to be drawn and sent to a laboratory for results that can be received long afterward. Instead, portable devices, like blood glucose meters, are being developed for easy, immediate results at home. This is particularly desirable because it allows for rapid delivery of results to doctors. Early diagnosis allows doctors to initiate treatment early, preventing the patient's condition from worsening due to untreated complications.

[0005] Blood is composed of blood cells, such as white blood cells and red blood cells, and plasma, each of which is used for different types of tests. From blood cells, we can find out things like HbA1c and hemoglobin levels, and from plasma, we can find out most various health information, such as cholesterol, glucose, liver function, and kidney function. The ratio of blood cells to plasma varies from person to person, and to accurately determine the amount of the measured item in each component, they must be separated and measured. If blood cells and plasma are mixed, it can cause disturbances in the measurement system, making accurate testing difficult.

[0006] Centrifuges are commonly used in laboratories to separate blood cells and plasma. However, portable devices are limited in size and power consumption, and the amount of blood collected through fingertip blood sampling is extremely small (5-70 μL), making it difficult to separate blood cells and plasma using conventional methods.

[0007] Because it is not easy to conduct blood tests, especially on infants and young children, blood is sometimes collected from capillary blood instead of venous blood drawn from a vein in a hospital, a compact system capable of accurately analyzing samples on site is required.

[0008] Meanwhile, microfluidics is a technology for manufacturing methods, devices, and systems that control fluid flow at the microscopic level. These systems, leveraging the aforementioned characteristics of microfluidics, have the advantage of being applicable to research on various biological phenomena.

[0009] This research field has made significant progress in the field of bio-implemented biochips, particularly since the Genome Project in the early 2000s, which developed DNA-based bio-responsive algorithms. This has led to the development of in vitro diagnostic techniques, such as molecular and blood diagnostics, based on diverse technical data. Furthermore, the discovery of numerous disease biomarkers and the establishment of miniaturized microfluidic systems have opened new avenues for developing methods and systems for predicting, diagnosing, and treating diseases in point-of-care testing or clinical settings.

[0010] However, existing Lab on a chip manufacturing technologies are manufactured using silicon and plastic injection or processing materials or processes such as PDMS (see Korean Patent Publication No. 10-2020-0042534). These materials have a difficult upper / lower plate bonding process, are vulnerable to some thermal deformation, and have a structure that is prone to fluid contamination.

[0011] In the case of fluid analysis cartridges (see Korean Patent No. 10-2054678 and Korean Patent No. 10-2103950), if the housing and the test section are manufactured separately and attached using double-sided tape, the separated blood may leak from the defective section and not be transported to the detection reagent section, or there may be insufficient blood to fill the reagent section chamber, resulting in inaccurate diagnostic results. In addition, this may result in serious defects in the reagent value, so the method of assembling the housing and the test section as separate products can be a disadvantage.

[0012] In addition, since the inspection section is open to the outside alone, there is a risk of contamination of the outermost corner with foreign substances from the external environment, and the circular hole window where the reagent is applied is more than 2 cm long and covers a wide area, which may affect the scanning accuracy of the optical detector.

[0013] Japanese Patent No. 4945709 relates to a simple testing device or method that can accurately measure a reaction by a liquid fluid, and supplies a sample using a cylindrical rubber stopper. Domestic Patent No. 10-2470360 relates to a filter that separates plasma and blood cells from blood, and although it is characterized by separation and extraction, it is not suitable for portable application.

[0014] Ultimately, to develop a portable, compact, integrated biochip for field testing, new microfluidic-based filter materials and basic technologies that apply mechanical structural technology within the chip are required.

[0015] (Patent Document 1) Domestic Publication No. 10-2020-0042534 (Published on April 23, 2020)

[0016] (Patent Document 2) Domestic Patent No. 10-2054678 (Registration Date: December 5, 2019)

[0017] (Patent Document 3) Domestic Patent No. 10-2103950 (Registration Date: April 17, 2020)

[0018] (Patent Document 4) Japanese Patent No. 4945709 (registration date: March 16, 2012)

[0019] (Patent Document 5) Domestic Patent No. 10-2470360 (Registration Date: November 21, 2020)

[0020] (Non-patent literature 1) Seungjun Lee et al., “Development of a blood separation biochip for point-of-care diagnostic applications,” Korean Society of Manufacturing Technology, Spring Conference Abstracts, p120 (2022).

[0021] The present invention has been devised to solve the above problems, and aims to provide a novel integrated biochip structure capable of injecting a blood (specimen) sample without using a tool such as a plunger, and perfectly separating and transporting blood cells and plasma of the blood.

[0022] In addition, the present invention aims to provide a biochip that can provide accurate test results and perform sample analysis on site even with a small amount of specimen sample.

[0023] In order to solve the above problem, the present invention provides a portable biochip having an integrated structure for on-site inspection, comprising: an inlet (100) and a supply hole (101) through which a specimen sample is introduced; a first round filter part (200) through which a sample is vertically passed downward through the inlet and separated for the first time; a first cross-sectional tape (250) positioned below so that a sample passing through the first filter part (200) can be transported; a connecting bridge part (300) in the shape of a bridge (∩) having a path through which the sample separated for the first time is transported for the second time separation; and a second cross-sectional tape (700) for sealing the connecting bridge part so as not to be exposed to the outside; a second filter part (400) through which a sample transported through the connecting bridge part is separated for the second time; A biochip is provided, which includes a rectangular type pattern film section (500) in which a sample that has passed through the second filter section is transferred to a pattern main hole (501), and then a detection reagent chamber (504) for examining the transferred sample is designed to have a structure having a microfluidic channel (502), a branch channel channel (503), and a plurality of reagent application areas by capillary force; and a detection window (600) through which the pattern film section can be observed.

[0024] The above specimen sample includes any one selected from body fluid, whole blood, blood, serum, plasma, cerebrospinal fluid, body tissue, urine, saliva, and sputum.

[0025] The above specimen sample comprises any one selected from those derived from humans, animals, plants, insects or cell cultures.

[0026] The above first filter unit (300) is in the form of a fiber matrix having an entangled structure, and is made of a material selected from the group consisting of polyethylene (PE), polypropylene (PP), polycarbonate (PC), polyethylene terephthalate (PET), and cellulose, and glass fiber (G / F), and includes at least one to three filters.

[0027] The above second filter unit (400) includes a film having an ultra-fine porous path of 1.5㎛ or less and a thickness of 0.03T-0.1T, and using any one material selected from the group consisting of polyethylene (PE), polypropylene (PP), polycarbonate (PC), and polyethylene terephthalate (PET).

[0028] The above pattern film portion (500) is made of a film made of polytetrafluoroethylene (PTFE) or polyvinylidene fluoride (PVDF) material, and a light-blocking ink can be printed except for the area where the reagent is applied.

[0029] The above pattern film portion (500) may have a geometric shape or patterned shape composed of one or more microfluidic channels (502) and two or more branch channel channels (503) for sample transport.

[0030] The above pattern film portion (500) may have a shape having a pressure release structure.

[0031] The above pressure relief structure may be composed of two light source passage holes (650) for the purpose of correcting the light source measurement value, and a curved surface depression (521, 522, 523) for pressure relief around a rectangular perimeter.

[0032] It further includes a label (800) with a QR code attached for information management of the above specimen sample.

[0033] As described above, the portable biochip developed and manufactured through the present invention has an integrated structure, and thus has the effect of improving errors in test results that may occur due to insufficient blood volume for testing due to leakage.

[0034] In addition, according to the present invention, when the sample is blood, it was difficult to conduct an accurate examination in a state where blood cells and plasma were mixed, but this can be completely resolved by the first and second filter sections having a porous structure and the connecting bridge section having a bridge shape (∩).

[0035] Additionally, it has the advantage of being simple and easy to use, as it can be measured by simply collecting a sample from a finger prick without using any instruments such as a plunger.

[0036] In addition, the uniformity of pressure discharge can be increased due to the curved surface depression on the side of the biochip according to the present invention, thereby increasing the stability of sample transport.

[0037] In addition, the present invention is portable and quick enough to confirm results immediately after testing with only a small amount of specimen sample, so it can be easily applied to various diagnostic fields that require immediate testing on site, as well as reducing costs.

[0038] FIG. 1 is a drawing illustrating a fluid analysis cartridge according to one embodiment of the prior art.

[0039] FIG. 2 is a perspective view and an exploded view illustrating a biochip according to one embodiment of the present invention.

[0040] FIG. 3 is a cross-sectional view illustrating a portable biochip according to one embodiment of the present invention.

[0041] Fig. 4 is an SEM photograph of the second filter part of the present invention.

[0042] Figure 5 is a drawing illustrating a pattern film portion (500) of various shapes of the present invention.

[0043] FIG. 6 is a perspective view and an exploded view illustrating a biochip according to another embodiment of the present invention.

[0044] FIG. 7 is a perspective view and an exploded view illustrating a biochip according to another embodiment of the present invention.

[0045] FIG. 8 is a drawing illustrating a pattern film portion (500) having a pressure release structure according to another embodiment of the present invention.

[0046] The present invention will now be described in more detail with reference to the attached drawings. However, the present invention may be implemented in various different forms and is not limited to the embodiments described herein.

[0047] In addition, terms or words used in this specification and claims should not be interpreted as limited to their usual or dictionary meanings, but should be interpreted as meanings and concepts that conform to the technical idea of ​​the present invention based on the principle that the inventor can appropriately define the concept of the term to explain his or her own invention in the best way.

[0048] FIG. 1 is a diagram illustrating the overall appearance of a fluid analysis cartridge according to one embodiment of the prior art, and is structured by being divided into a housing (110) that supports the cartridge and a test section (120) where a fluid and a reagent meet and a reaction occur.

[0049] That is, since the housing and the inspection section are manufactured separately and joined using double-sided tape, the separated blood may leak from the defective section when attached and not be transported to the inspection chamber, or there may be insufficient blood to fill the entire inspection chamber, resulting in inaccurate diagnosis results. Therefore, the method of assembling each product separately may have the above problems.

[0050] In addition, the above cartridge separates and transports blood after injecting blood into the upper part of the housing, and is a method of moving and separating or transporting blood by applying a constant pressure only to the upper part.

[0051] Since this is a method of applying pressure by placing a special pressurizing device, such as a plunger, in contact with the top of the housing, if there is surface damage or a scratch on the part where the plunger makes contact, the pressurized pressure will leak and not be able to transmit sufficient pressure to the blood, which may eventually cause abnormalities in blood separation or cause defects due to poor blood transport.

[0052] Accordingly, the inventor of the present invention has already applied for an integrated biochip with a novel separation structure to address the aforementioned issues (Patent Application No. 10-2022-0121876). This integrated design offers the advantage of improving test results due to insufficient blood volume due to leakage and allowing the use of small amounts of blood.

[0053] However, the biochip also features an additional suction section designed to ensure sufficient pressure is applied to the blood sample, which is dropped into the supply hole using a tool such as a pipette or dropper. Therefore, it is insufficient for on-site analysis of small amounts of blood collected through fingertip capillary blood collection.

[0054] Accordingly, the portable biochip of an integrated structure according to one embodiment of the present invention is designed so that when a blood sample is introduced vertically and then transported through a first filter section, only plasma can pass through a bridge (∩)-shaped path using a capillary phenomenon, and then when it passes through a second filter section, only plasma can be completely separated and transported, so that the blood (specimen) extracted and separated without power can be optically detected for discoloration or degree of color development of a reagent through a rectangular pattern film section.

[0055] FIG. 2 is a perspective view and an exploded view illustrating a portable biochip according to one embodiment of the present invention, and FIG. 3 is a cross-sectional view illustrating a portable biochip according to one embodiment of the present invention.

[0056] This portable biochip, designed and manufactured in a compact, integrated form factor, offers the advantage of rapid, on-site testing of specimens (point-of-care testing, POCT) regardless of location. Specifically, blood samples collected from the human body can be tested in a simple, on-site manner, by patients, physicians, nurses, and clinical pathologists, eliminating the need for central laboratories where venous blood samples are collected. These tests can be performed at home, work, outpatient clinics, hospital rooms, emergency rooms, operating rooms, and intensive care units, simply by collecting capillary blood samples.

[0057] On one side of the body of the biochip for analysis, a supply hole (101) is provided in an inlet (100) through which a specimen sample is introduced. This may be formed in a circular shape as illustrated in Fig. 2, but is not limited thereto and a polygonal shape is also possible.

[0058] Since blood flows in and comes into contact with the body through the supply hole, it is desirable to select a material that is easy to mold and chemically and biologically inert. Examples of suitable materials include polyethylene such as linear low-density polyethylene (LLDPE), low-density polyethylene (LDPE), medium-density polyethylene (MDPE), and high-density polyethylene (HDPE), polypropylene (PP), polyvinyl alcohol (PVA), polymethyl methacrylate (PMMA), polydimethylsiloxane (PDMS), polycarbonate (PC), and acrylonitrile butadiene styrene copolymer (ABS).

[0059] The biochip can collect a specimen sample directly from a finger prick and deliver it to the injection port (100). Since it is intended for portable use, the sample volume is appropriately about 1 to about 100 microliters, preferably about 5 to about 70 microliters, and more preferably about 15 to about 20 microliters.

[0060] The above specimen sample includes body fluids, whole blood, blood, serum, plasma, cerebrospinal fluid, body tissue, urine, saliva, sputum, etc. The specimen sample may also be derived from humans, animals, plants, insects, or cell cultures.

[0061] Here, injecting the blood sample vertically rather than horizontally can increase the sedimentation effect of blood cells when passing through the first filter via the supply hole (101), and has the advantage of allowing the blood sample to safely fall toward the lower injection port without being lost to the side.

[0062] A method of transporting the above specimen sample by applying the depressurization and pressurization methods alone or simultaneously can be additionally combined as needed (not shown).

[0063] In addition, a first round filter unit (200) is provided that is vertically passed downward through the inlet to perform the first separation. It is preferable to seal the first filter unit (200) so that it is not exposed to the outside by a first cross-section tape (250) located below so that the sample that has passed through the first filter unit (200) can be transported.

[0064] The first filter unit (300) is in the form of a fiber matrix having an entangled structure, and the material may be composed of any one resin selected from the group consisting of polyethylene (PE), polypropylene (PP), polycarbonate (PC), polyethylene terephthalate (PET), and cellulose, and glass fiber (G / F). It is a porous filter structure that separates a sample by passing it through gaps of various sizes created between the fibers of the entangled structure.

[0065] To preferentially remove large blood cells from a blood sample, one or more porous filters, such as the above, are placed on the lower side of the blood flow path. That is, by providing sheets with a specific, laminated structure, large blood cells can be primarily separated. It is preferable to use at least three porous filters in a stacked manner, as the more layers there are, the more readily the blood cell sedimentation effect can be achieved.

[0066] In addition, a bridge-shaped (∩) connecting bridge (300) having a path through which the first separated sample is transferred for second separation; and a second cross-section tape (700) that seals the bridge so that it is not exposed to the outside are provided.

[0067] When transported through the above-mentioned bridge-structured microchannel, only plasma can pass through, utilizing capillary action without power, preventing blood cell components from passing. This newly designed structure was introduced. Other examples include curved, zigzag, or meandering shapes, but the bridge structure is most preferred. The microchannel width can be selected from 100 to 1,000 microns.

[0068] The material of the first cross-section tape (250) and the second cross-section tape (700) may be selected from transparent or opaque plastic, paper, or metal, but is not limited thereto.

[0069] In addition, a second filter section (400) is provided for secondary separation of the sample transferred through the above-mentioned connecting bridge section. Due to the additional second filter section configuration in addition to the first filter section, the separation efficiency and function of the sample are further enhanced, and the penetration stability is also improved. Blood cells with a size of approximately 1.5-10㎛ are filtered out, and only the plasma is transferred to the pattern main hole (501).

[0070] In other words, when passing through the second filter section, only the plasma in the blood can be completely separated, greatly increasing the accuracy of the final test results.

[0071] The second filter unit (400) may be formed in a film shape with an ultra-fine porous path of 1.5㎛ or less and a thickness of 0.03T-0.1T, and may be made of any one material selected from the group consisting of polyethylene (PE), polypropylene (PP), polycarbonate (PC), and polyethylene terephthalate (PET). Fig. 4 is an SEM photograph of the second filter unit.

[0072] In addition, a rectangular type pattern film section (500) is provided in which a sample that has passed through the second filter section is transferred to a pattern main hole (501), and then a plurality of detection reagent chambers (504) in which a reaction between the transferred sample and the reagent occurs through a structure having a microfluidic channel (502), a branch channel channel (503), and a plurality of reagent application areas by capillary force are designed (see FIG. 5).

[0073] The above pattern film portion (500) is made of a film or sheet made of polytetrafluoroethylene (PTFE) or polyvinylidene fluoride (PVDF) material, and is printed with a light-blocking ink except for the area where the reagent is applied. Here, the term "sheet" can be used interchangeably with the term "film" and refers to a layer on which a pattern is formed.

[0074] The surface on which the above ink is printed is black, but is not limited to this and may be of any other color as long as it has light-blocking properties.

[0075] A pressure-sensitive adhesive (PSA) can be used for bonding the biochip body for analysis and the pattern film portion. PSA has the characteristics of being able to bond to an adherend in a short time with pressure equivalent to that of a finger at room temperature, not causing cohesive destruction when peeled, and not leaving residue on the surface of the adherend.

[0076] The above pattern film portion (500) may take the form of a geometric shape or patterned shape consisting of one or more microfluidic channels (502) and two or more branch channel channels (503) for sample transport.

[0077] FIG. 5 is a drawing illustrating a pattern film unit (500) of various shapes of the present invention. (a) (b) (c) are structures in which a plurality of branched microfluidic channels (502), branch channel channels (503), and detection reagent chambers (504) are connected in a grape shape, (d) is a structure in which four branch channel channels (503) and detection reagent chambers (504) are radially connected, and (e) is a structure having the same shape as (a) but differing only in length, in which a plurality of branch channel channels (503) are positioned along two microfluidic channels (502). At this time, each branch channel channel is connected to a detection reagent chamber (504). FIG. 6 is a perspective view and an exploded view illustrating a portable biochip using a pattern film unit having a shape of (e) as another embodiment of the present invention.

[0078] The size of the above pattern film portion is preferably 12 X 15 mm, which is a rectangular size suitable for use as a portable biochip.

[0079] In some cases, pressure and capillary force alone may not be sufficient to completely transport a liquid (blood) sample through microfluidic channels and branch channel channels. Therefore, after numerous repeated experiments and trial and error, the inventors of the present invention have developed a patterned film section with a different external structure to address this issue.

[0080] FIG. 7 is a perspective view and an exploded view illustrating a biochip according to another embodiment of the present invention, and FIG. 8 is a drawing illustrating a pattern film portion having a pressure release structure according to the above embodiment.

[0081] The pattern film portion (500) having the above pressure release structure has two light source passage holes (650) for the purpose of correcting the light source measurement value, and a curved surface depression (521, 522, 523) structure for pressure release formed around the circumference of the rectangle.

[0082] This can improve the sensitivity of the light source by introducing a light source passage hole (650) structure on each of the left and right sides of the upper part of the biochip film, and can also increase the surface area by forming a surface depression (521, 522, 523) processed in a curved shape on the side of the biochip, thereby improving the uniformity of pressure discharge, which ultimately has the effect of increasing the stability of sample transport.

[0083] The above hole is an empty area, unlike a structure having an area coated with a reagent for detecting analyte (sample), which can be used for light source measurement correction.

[0084] For example, a light beam emitted from an LED can pass through a microfluidic cartridge and be detected by a CCD detector from below. Another example is a detection system that utilizes a spectrometer to detect reflected light.

[0085] In particular, in the multiple detection reagent chambers (504), the degree of color development or discoloration caused by the reaction between the transferred blood sample (particularly plasma) and the reagent can be optically detected and quantified. Through the above quantification, the presence or absence of a specific component in the blood or the ratio of a specific component can be confirmed. Although this is designed to be circular, a polygonal shape such as a square is also possible, and the number of detection reagent chambers is sufficient as long as the reliability of the test results is ensured.

[0086] In addition, a detection window (600) capable of observing the above-mentioned pattern film portion is provided. Through this, optical information of the detection reagent chamber can be quickly confirmed.

[0087] Additionally, a label (800) with a QR code attached may be further included for information management of various specimen samples.

[0088] The present invention has designed an integrated structure that directly collects and transports a sample by simply pricking a finger when the specimen sample is blood. This has the technical feature of allowing rapid, portable testing and judgment on site, as it can be confirmed that even a very small amount of specimen is sufficiently transported to the detection reagent chamber via a bridge-shaped (∩) connecting leg.

Claims

1. In a portable biochip having an integrated structure for field inspection, An inlet (100) and a supply hole (101) through which a specimen sample is introduced; A first round filter part (200) that is vertically passed downward through the above injection port and is first separated; A first cross-section tape (250) positioned below so that a sample passing through the first filter section (200) can be transported; A connecting bridge (300) in the shape of a bridge (∩) having a path through which the first separated sample is transferred for second separation; and a second cross-section tape (700) that seals the bridge so that it is not exposed to the outside; A second filter section (400) in which the sample transferred through the above connecting bridge section is separated for the second time; A rectangular type pattern film section (500) designed with a detection reagent chamber (504) for examining a sample that has passed through the second filter section and is then transferred to a pattern main hole (501) and then transferred to a structure having a microfluidic channel (502), a branch channel channel (503) and a plurality of reagent application areas by capillary force; and A biochip including a detection window (600) capable of observing the above pattern film portion; 2. In claim 1, The specimen sample is a biochip containing any one selected from body fluid, whole blood, blood, serum, plasma, cerebrospinal fluid, body tissue, urine, saliva, and sputum.

3. In claim 1, A biochip comprising a specimen sample selected from among those derived from human, animal, plant, insect or cell culture.

4. In claim 1, The above first filter unit (300); is in the form of a fiber matrix having an entangled structure, and the material is composed of a resin selected from the group consisting of polyethylene (PE), polypropylene (PP), polycarbonate (PC), polyethylene terephthalate (PET), and cellulose, and glass fiber (G / F), and is a biochip including at least one to three filters.

5. In claim 1, The above second filter unit (400); is a biochip comprising a film having an ultra-fine porous path of 1.5㎛ or less and a thickness of 0.03T-0.1T, and using any one material selected from the group consisting of polyethylene (PE), polypropylene (PP), polycarbonate (PC), and polyethylene terephthalate (PET).

6. In claim 1, The above pattern film portion (500) is made of a film made of polytetrafluoroethylene (PTFE) or polyvinylidene fluoride (PVDF) material, and is a biochip printed with a light-blocking ink except for the area where the reagent is applied.

7. In claim 1, The above pattern film portion (500); is a biochip having a geometric shape or patterned shape consisting of one or more microfluidic channels (502) and two or more branch channel channels (503) for sample transport.

8. In claim 1, The above pattern film portion (500) is a biochip having a structure for pressure release.

9. In claim 8, The above pressure release structure is a biochip consisting of two light source passage holes (650) for the reference of light source measurement value correction, and a curved surface depression (521, 522, 523) structure for pressure release around a rectangular perimeter.

10. In claim 1, A biochip further comprising a label (800) with a QR code attached for managing information on a specimen sample;

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