WO2011154918A2

WO2011154918A2 - Diagnostic apparatus for immunoassay and diagnostic method for immunoassay using the same

Info

Publication number: WO2011154918A2
Application number: PCT/IB2011/052526
Authority: WO
Inventors: Jaean Jung; Jae Kyung Choi; Young Ho Choi
Original assignee: Medisensor Gh, Inc.
Priority date: 2010-06-09
Filing date: 2011-06-09
Publication date: 2011-12-15
Also published as: WO2011154918A3

Abstract

A diagnostic apparatus for immunoassay is provided. The diagnostic apparatus includes a microfluidic chip having fluorescent nanoparticle-biomaterial composites to detect a biological sample, a light source unit providing flat light to the microfluidic chip to generate fluorescence energy caused by a fluorescence resonance energy transfer (FRET) effect between the fluorescent nanoparticle-biomaterial composites, a sensing unit configured to sense the fluorescence energy emitted from the microfluidic chip, a measuring unit configured to convert the fluorescence energy sensed by the sensing unit into a current peak, a display unit configured to convert the current peak into an image, and a power supply unit using a solar low power circuit to supply power required for operations of the light source unit, the sensing unit, the measuring unit, and the display unit. The fluorescent nanoparticle- biomaterial composite is specifically bound to the biological sample to form a fluorescent nanoparticle-bio-conjugated material composite.

Description

DIAGNOSTIC APPARATUS FOR IMMUNOASSAY AND DIAGNOSTIC METHOD FOR IMMUNOASSAY USING THE SAME

BACKGROUND

Technical Field

[0001 ] The present invention relates to diagnostic apparatuses and methods for immunoassay. More specifically, the present invention is directed to a portable diagnostic apparatus for immunoassay and a diagnostic method for immunoassay using the same.

Description of Related Art

[0002] Test methods for use in diagnosis of diseases are mainly based on

chromogenic character and fluorescence caused by enzyme reaction. However, immunoassay methods have been used in recent years. The term "immunoassay" is a technology utilizing an immunological reaction between an antigen and an antibody. According to these immunoassay methods, an antigen is labeled with a radioisotope or a fluorescent material to determine whether there is an antibody. The immunoassay methods use a label biosensor which can be quantified by radiation or fluorescence.

[0003] Conventionally, two methods have been most widely used as an immunoassay method. One is a method for measuring a signal obtained by labeling an antigen or antibody with a radioactive material, a luminescent material or a fluorescent material, and the other is an optical measuring method such as enzyme linked immunosorbent assay (ELISA) or Western Blotting. Disadvantageously, each of the two methods requires a complex procedure that is usually performed in a laboratory by a skillful researcher, a high-cost and large-sized apparatus for analysis, and long time for analysis.

[0004] An antibody, which is a target material of an immunosensor, or the like exists at a considerably low concentration in a biological sample such as whole blood, serum, and urine. Hence the immunosensor need to be provided with a high-sensitivity signaling technology that is much more excellent in detection limitation of a sensor than a biosensor technology for detecting other material. In addition, because the structure of a protein such as an antibody or a protein antigen readily varies with change of an external environment, the protein is vulnerable to lose its own intrinsic biological recognition function due to deformation of recognition sites. Considering that an immunosensor must be analyzed under a solid state, there are needs for manufacturing of a sensor surface suitable for a biomaterial that is capable of maintaining activation of biomaterials, a biomaterial fixation technology that is capable of enhancing detection limitation, and a measuring method of converting biological recognition reaction into a quantified signal.

[0005] A rapid diagnostic test kit for immunoassay (hereinafter referred to as "rapid diagnostic test kit") is a test apparatus for point-of-care test and diagnosis which can be conducted using a biological sample such as blood, urine, and saliva. Examples of the rapid diagnostic test kit are a pregnancy diagnostic kit and an AIDS diagnostic kit.

[0006] Such a diagnostic apparatus must establish a method of detecting a predetermined biomaterial (e.g., protein, DNA, etc.) for diagnosis. A fluorescence labeling method is well-known as a conventional biomaterial detection method. Fluorescent labels emit various colors according to their kinds to provide means for detecting a target biomaterial. [0007] A plurality of fluorescent labels emitting different colors are needed to simultaneously detect a plurality of biomaterials. When a plurality of colors are emitted at the same time, photob leaching may occur. Moreover, a conventional fluorescent label is disadvantageous in optically small excitation and emission bandwidth. In case of being bound to a biomaterial, the conventional fluorescent label may have an adverse effect on activation of the biomaterial.

[0008] Accordingly, there is a need for a physically more stable and functional labeling method which is capable of overcoming the above-mentioned disadvantages of the conventional labeling method. In addition, there is a need for a more stable and accurate method of simultaneously detecting a plurality of biomaterials.

[0009] In view of the foregoing needs, labeling methods using semiconductor quantum dot (QD) nanoparticles are being introduced in recent years. Unfortunately, conventional QD nanoparticles exhibit a low binding property to a labeling-target biomaterial while being physically stable, and limitation in processing g a QD nanoparticle surface is still not overcome. Therefore, conventional QD nanoparticles have been only used as labeling sources for optical analysis methods.

[0010] Accordingly, there is a need for a novel labeling method using nanoparticles which is capable of being successfully bound to a biomaterial and easily detecting the biomaterial.

[0011 ] Chemical chromogenic character for use in a conventional rapid diagnostic kit is designed such that the amount of chromogenic character is determined according to the amount of an analysis target in a sample and a concentration over a predetermined level can be checked with the naked eye. It is known that limitation in concentration of an analysis target capable of being checked by such a chemical development reaction is about 10^~6~10 ,-9 mol.

SUMMARY

[0012] Embodiments of the inventive concept provide a diagnostic apparatus for immunoassay. According to exemplary embodiments of the inventive concept, the diagnostic apparatus may include a microfluidic chip having fluorescent nanoparticle-biomaterial composites to detect a biological sample, a light source unit providing flat light to the microfluidic chip to generate fluorescence energy caused by a fluorescence resonance energy transfer (FRET) effect between the fluorescent nanoparticle-biomaterial composites, a sensing unit configured to sense the fluorescence energy emitted from the microfluidic chip, a measuring unit configured to convert the fluorescence energy sensed by the sensing unit into a current peak, a display unit configured to convert the current peak into an image, and a power supply unit using a solar low power circuit to supply power required for operations of the light source unit, the sensing unit, the measuring unit, and the display unit. The fluorescent nanoparticle-biomaterial composite may be specifically bound to the biological sample to form a fluorescent nanoparticle-bio-conjugated material composite.

[0013] In some embodiments of the inventive concept, the microfluidic chip may have at least two kinds of fluorescent nanoparticle-biomaterial composites.

[0014] In some embodiments of the inventive concept, the fluorescent nanoparticle- biomaterial composite may be formed by means of one selected from the group consisting of a gas phase condensation method, a high frequency plasma chemical synthesis method, conventional chemical precipitation method, a hydrothermal synthesis method, an electric dispersion reaction method, a combustive synthesis method, a sol-gel synthesis method, a thermochemical synthesis method, a microfludizer process, a microemulsion technique, and a high energy mechanical milling technique.

[0015] In some embodiments of the inventive concept, fluorescent nanoparticle of the fluorescent nanoparticle-biomaterial composite may include at least one selected from the group consisting of metal nanoparticle, quantum dot, organic nanoparticle, and lanthanide- based fluorescent nanoparticle. The metal nanoparticle may include one selected from the group consisting of gold (Au), silver (Ag), copper (Cu), aluminum (Al), nickel (Ni), cobalt (Co), iron (Fe), zinc (Zn), and manganese (Mn).

[0016] In some embodiments of the inventive concept, a biomaterial of the fluorescent nanoparticle-biomaterial composite may include at least one selected from the group consisting of nucleic acid containing DNA or RNA, amino acid, fat, glycoprotein, and antibody.

[0017] In some embodiments of the inventive concept, in the case that an infectious disease included in a biological sample specifically bound to a fluorescent nanoparticle- biomaterial composite is an antigen, a biomaterial of the fluorescent nanoparticle-biomaterial composite may be an antibody.

[0018] In some embodiments of the inventive concept, the light source unit may include a high-brightness light emitting diode (LED) and a light guide plate. The light source unit may provide multi-wavelength flat uniform light.

[0019] In some embodiments of the inventive concept, the diagnostic apparatus may further include an optical filter disposed between the light source unit and the microfluidic chip to provide single-wavelength flat uniform light to the microfluidic chip. [0020] In some embodiments of the inventive concept, the measuring unit may convert two-dimensional type fluorescence energy sensed by the sensing unit into an electrical signal. The measuring unit may accumulate an electrical signal after converting the two-dimensional type fluorescence energy into the electrical signal.

[0021 ] In some embodiments of the inventive concept, the measuring unit may analyze kinds of infectious diseases included in the biological sample and the infection degree thereof by analyzing the electrical signal.

[0022] Embodiments of the inventive concept also provide a diagnostic method for immunoassay. According to exemplary embodiments of the inventive concept, the diagnostic method may include injecting a biological sample into a micro fluidic chip having fluorescent nanoparticle -biomaterial composites such that the fluorescent nanoparticle-biomaterial composites are specifically bound to a biological sample to form fluorescent nanoparticle- bio-conjugated material composites, providing flat uniform light to the microfluidic chip to generate fluorescence energy caused by a fluorescence resonance energy transfer (FRET) effect between the fluorescent nanoparticle-bio-conjugated material composites, collecting the fluorescence energy emitted from the microfluidic chip, converting the collected fluorescence energy into an electrical signal, and converting the electrical signal into an image.

[0023] In some embodiments of the inventive concept, the microfluidic chip may have at least two kinds of fluorescent nanoparticle-biomaterial composites.

[0024] In some embodiments of the inventive concept, the fluorescent nanoparticle- biomaterial composite may be formed by means of one selected from the group consisting of a gas phase condensation method, a high frequency plasma chemical synthesis method, conventional chemical precipitation method, a hydrothermal synthesis method, an electric dispersion reaction method, a combustive synthesis method, a sol-gel synthesis method, a thermochemical synthesis method, a microfludizer process, a microemulsion technique, and a high energy mechanical milling technique.

[0025] In some embodiments of the inventive concept, fluorescent nanoparticles of the fluorescent nanoparticle-biomaterial composite may include at least one selected from the group consisting of metal nanoparticle, quantum dot, organic nanoparticle, and lanthanide- based fluorescent nanoparticle. The metal nanoparticle may include one selected from the group consisting of gold (Au), silver (Ag), copper (Cu), aluminum (Al), nickel (Ni), cobalt (Co), iron (Fe), zinc (Zn), and manganese (Mn).

[0026] In some embodiments of the inventive concept, a biomaterial of the fluorescent nanoparticle-biomaterial composite may include at least one selected from the group consisting of nucleic acid containing DNA or RNA, amino acid, fat, glycoprotein, and antibody.

[0027] In some embodiments of the inventive concept, in the case that an infectious disease included in a biological sample specifically bound to a fluorescent nanoparticle- biomaterial composite is an antigen, a biomaterial of the fluorescent nanoparticle-biomaterial composite may be an antibody.

[0028] In some embodiments of the inventive concept, the flat uniform light may be single-wavelength flat uniform light.

[0029] In some embodiments of the inventive concept, collecting the fluorescence energy emitted from the microfluidic chip may be collecting two-dimensional type fluorescence energy by providing the flat uniform light to the microfluidic chip. Collecting the fluorescence energy emitted from the microfluidic chip may be collecting and accumulating two-dimensional type fluorescence energy.

[0030] In some embodiments of the inventive concept, the diagnostic method may further include analyzing kinds of infectious diseases included in the biological sample and the infection degree thereof by analyzing the electrical signal.

BRIEF DESCRIPTION OF THE DRAWINGS

[0031 ] In the following, some example embodiments of the inventive concept will be explained in more detail with reference to the drawing, in which:

[0032] FIG. 1 is a block diagram illustrating the configuration of a diagnostic apparatus for immunoassay according to embodiments of the inventive concept; and

[0033] FIG. 2 is a cross-sectional view illustrating the operation of a diagnostic apparatus for immunoassay according to embodiments of the inventive concept.

DETAILED DESCRIPTION OF THE EMBODIMENTS

[0034] The inventive concept will now be described more fully hereinafter with reference to the accompanying drawings, in which preferred embodiments of the inventive concept are shown. However, the inventive concept may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the inventive concept to those skilled in the art. In the drawings, the thicknesses of layers and regions are exaggerated for clarity. It will also be understood that when a layer is referred to as being "on" another layer or substrate, it can be directly on the other layer or substrate, or intervening layers may also be present. Like numbers refer to like elements throughout.

[0035] As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items. It will be understood that when an element is referred to as being "connected" or "coupled" to another element, it may be directly connected or coupled to the other element or intervening elements may be present. It will be further understood that the terms "comprises", "comprising,", "includes" and/or "including", when used herein, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

[0036] Exemplary embodiments of the invention will be described below with reference to cross-sectional views, which are exemplary drawings of the invention. The exemplary drawings may be modified by manufacturing techniques and/or tolerances. Accordingly, the exemplary embodiments of the invention are not limited to specific configurations shown in the drawings, and include modifications based on the method of manufacturing the semiconductor device. For example, an etched region shown at a right angle may be formed in a rounded shape or formed to have a predetermined curvature. Therefore, regions shown in the drawings have schematic characteristics. In addition, the shapes of the regions shown in the drawings exemplify specific shapes of regions in an element, and do not limit the invention.

[0037] FIG. 1 is a block diagram illustrating the configuration of a diagnostic apparatus 100 for immunoassay according to embodiments of the inventive concept. As illustrated, the diagnostic apparatus 100 includes a microfluidic chip 1 10, a light source unit 120, a sensing unit 130, a measuring unit 140, a display unit 150, and a power supply unit 160.

[0038] The microfluidic chip 1 10 may have fluorescent nanoparticle -biomaterial composites for detecting infectious diseases included in a biological sample. The fluorescent nanoparticle-biomaterial composite may be specifically bound to the infectious disease included in the biological sample to form a fluorescent nanoparticle-bio-conjugated material composite.

[0039] Fluorescent nanoparticle of the fluorescent nanoparticle-biomaterial composite may include at least one selected from the group consisting of metal nanoparticle, quantum dot (QD), organic nanoparticle, and lanthanide-based fluorescent nanoparticle.

[0040] In case of including metal nanoparticle, fluorescent nanoparticle may further include a fluorescent substance. The fluorescent substance may cause a fluorescence resonance energy transfer (FRET) effect. In nanoparticles, fluorescent substances approach each other to cause a FRET effect and particularly may emit fluorescent light of red or near infrared (IR) ray. The fluorescent substance may be a fluorescent substance of high quantum efficiency. The metal nanoparticle may include one selected from the group consisting of gold (Au), silver (Ag), copper (Cu), aluminum (Al), nickel (Ni), cobalt (Co), iron (Fe), zinc (Zn), and manganese (Mn).

[0041 ] The QD may be an II-IV semiconductor nanoparticle or an AglnZnS semiconductor nanoparticle. The II-IV semiconductor nanoparticle may be cadmium selenide (CdSe), cadmium telluride (CdTe) or cadmium sulfide (CdS). The organic nanoparticle may include oligomeric benzoxazole or 2-(2'-deuteriooxyphenyl) benzoxazole (DOB). The lanthanide-based fluorescent nanoparticle may include chelate-binding lanthanide-based elements having time-resolved fluorescence characteristics.

[0042] The fluorescent nanoparticle-biomaterial composite may be formed by means of one selected from the group consisting of a gas phase condensation method, a high frequency plasma chemical synthesis method, conventional chemical precipitation method, a hydrothermal synthesis method, an electric dispersion reaction method, a combustive synthesis method, a sol-gel synthesis method, a thermochemical synthesis method, a microfludizer process, a microemulsion technique, and a high energy mechanical milling technique.

[0043] In the case that an infectious disease included in a biological sample specifically bound to a fluorescent nanoparticle-biomaterial composite is an antigen, a biomaterial of the fluorescent nanoparticle-biomaterial composite may be an antigen.

[0044] The microfluidic chip 1 10 may have at least two kinds of fluorescent nanoparticle-biomaterial composites. Thus, the microfluidic chip 1 10 may detect a plurality of infectious diseases included in the biological sample at the same time.

[0045] The microfluidic chip 1 10 may perform not only operations such as transfer, stop, and speed change of a biological sample such as a fluid biological sample, i.e., blood but also operations such as mixture, extraction, and replacement of another fluid such as a test solution. The microfluidic chip 1 10 may be implemented considering factors, such as width, depth, and length of a fluid channel, which may have an influence on the flow of a fluid, a kind of polymer used as a material, a kind of a fluid for use in detection, and a contact angle. Moreover, the microfluidic chip 1 10 may be implemented considering factors such as kind, type, and installation position of a pump and a value for efficiently transferring a fluid. [0046] A biological sample taken out of an infected patient to be medically examined is injected to the microfluidic chip 1 10 without a pre-processing procedure. While migrating along a fluid channel, a mixture of the biological sample and a reactive solution takes a physical conjugation of an infectious disease included in the biological sample and a fluorescent nanoparticle-biomaterial composite.

[0047] The light source unit 120 may provide flat uniform light to the microfluidic chip 1 10. The flat uniform light provided by the light source unit 120 may generate fluorescence energy caused by a fluorescence resonance energy transfer (FRET) effect between fluorescent nanoparticle-bio-conjugated material composites of the microfluidic chip 110. Since an infectious disease is checked using the fluorescence energy generated by the FRET effect, detection limitation and sensitivity may be improved to detect an infectious disease that exists at a considerably low concentration (<10^~17 mol) in a biological sample of ultra small amount (10^~9~10^~12 /)·

[0048] Since the flat uniform light is provided to the microfluidic chip 1 10 from the light source unit 120, the fluorescence energy generated by the FRET effect may be two- dimensionally sensed by the sensing unit 130.

[0049] The light source unit 120 may include a high-brightness light emitting diode

(LED) and a light guide plate. Multi-wavelength flat uniform light may be generated by the high-brightness LED and the light guide plate. An optical filter 125 may be provided between the light source unit 120 and the microfluidic chip 1 10 to provide a single- wavelength flat uniform light. The multi- wavelength flat uniform light generated from the light source unit 120 may turn to a specific single-wavelength flat uniform light while passing the optical filter 125. The optical filter 125 may be a chopper-type filter, i.e., a single chopper is provided with various types of optical filters 125. Accordingly, various specific single-wavelength flat uniform lights may be provided to the microfluidic chip 1 10.

[0050] In the case that the microfluidic chip 1 10 has at least two kinds of fluorescent nanoparticle-biomaterial composites, different fluorescence energies may be generated between a pair of the respective at least two kinds of fluorescent nanoparticle-bio-conjugated material composites. Thus, fluorescence energy for a plurality of infectious diseases included in a biological sample may be generated.

[0051 ] As set forth above, the sensing unit 130 may two-dimensionally sense fluorescence energy generated by a FRET effect between a pair of fluorescent nanoparticle- bio-conjugated material composites. The sensing unit 130 may be maintained at a distance from the microfluidic chip 1 10 to sense fluorescence energy emitted radially without specific orientation and may be structured to surround three sides. Also the sensing unit 130 may include a high-sensitivity detector (137 in FIG. 2).

[0052] The measuring unit 140 may convert the fluorescence energy sensed by the sensing unit 130 into an electrical signal. The electrical signal may be a signal of current peak type. The measuring unit 140 may accumulate fluorescence energy sensed by the sensing unit 130 after converting the fluorescence energy into an electrical signal. Because the measuring unit 140 accumulates an electrical signal of current peak type, detection sensitivity to fluorescence energy generated by a FRET effect between a pair of fluorescent nanoparticle-bio-conjugated material composites of the microfluidic chip 1 10 may be improved.

[0053] In the case that the microfluidic chip 1 10 has at least two kinds of fluorescent nanoparticle-biomaterial composites, different fluorescence energies may be generated between a pair of the respective at least two kinds of fluorescent nanoparticle-biomaterial composites. The different fluorescence energies may be electrical signals of different current peak types, respectively. This makes it possible to measure an electrical signal including current peaks for a plurality of infectious diseases included in a biological sample.

[0054] The measuring unit 140 may analyze kinds and degrees of infectious diseases, which are included in a biological sample, corresponding to current peaks by analyzing an electrical signal of current peak type. Accordingly, each of the infectious diseases included in the biological sample may be analyzed qualitatively and quantitatively. In addition, the infectious diseases included in the biological sample may be analyzed at the same time.

[0055] The display unit 150 may convert an electrical signal converted by the measuring unit 140 into an image. The display unit 150 displays the electrical signal converted by the measuring unit 140 as an image, which allows the naked eye to check whether the respective infectious diseases included in the biological sample are infected and the infection degree of the respective infectious diseases. Therefore, a diagnostic apparatus 100 for immunoassay may be provided to qualitatively and quantitatively check whether each of a plurality of infectious diseases included in a biological sample is infected and the infection degree of the respective infectious diseases.

[0056] The power supply unit 160 may supply power required for operations of the light source unit 120, the sensing unit 130, the measuring unit 140, and the display unit 150. The power supply unit 160 may utilize a solar low power circuit. Since the power supply unit 160 utilizes the solar low power circuit, a separate external power supply may be required. Therefore, an easily transferable and portable diagnostic apparatus 100 for immunoassay may be provided. [0057] FIG. 2 is a cross-sectional view illustrating the operation of a diagnostic apparatus for immunoassay according to embodiments of the inventive concept.

[0058] Referring to FIG. 2, a microfluidic chip 1 10 includes fluorescent nanoparticle- bio-conjugated material composites formed by specifically binding an infectious disease included in a biological sample to fluorescent nanoparticle-biomaterial composites. The microfluidic chip 1 10 may include at least two kinds of fluorescent nanoparticle-bio- conjugated material composites.

[0059] Flat uniform light is provided from a light source unit 120. The flat uniform light provided from the light source unit 120 impinges onto the fluorescent nanoparticle -bio- conjugated material composites of the microfluidic chip 1 10 through a beam splitter 132 of a sensing unit 130. The flat uniform light impinging onto the fluorescent nanoparticle-bio- conjugated material composites of the microfluidic chip 1 10 may cause a fluorescence resonance energy transfer (FRET) effect between a pair of fluorescent nanoparticle-bio- conjugated material composites of the microfluidic chip 110. Due to the FRET effect, fluorescence energy is radially emitted. The radially emitted fluorescence energy is transmitted to a mirror 133 via an objective lens 131, as a type of fluorescence beam. The fluorescence beam reflected by the mirror 133 is transmitted to a focusing lens 135 via a filter 134. Specific single-wavelength fluorescence beam is converged to the focusing lens 135. While passing a confocal pinhole 136, the converged fluorescence beam is diverged to be sensed by a detector 137 of the sensing unit 130.

[0060] The sensing unit 130 may employ a temporal difference detection technology to prevent energy straggling caused by the flat uniform light provided from the light source unit 120. In addition, the sensing unit 130 may employ scattered light processing, noise canceling, and pattern recognition technologies for the sensed fluorescence beam.

[0061 ] Since an infectious disease of a biomaterial is checked using fluorescence energy generated by the FRET effect between a pair of fluorescent nanoparticle-bio- conjugated material composites of the microfluidic chip 1 10, detection limitation and sensitivity may be improved to detect an infectious disease that exists at a considerably low concentration (<10^~17 mol) in a biological sample of ultra small amount (10^~9~10^~12 I).

[0062] Since flat uniform light is provided to the microfluidic chip 1 10 from the light source unit 120, the fluorescence energy generated by the FRET effect may be two- dimensionally sensed by the detector 137 of the sensing unit 130.

[0063] The filter 134 may be a chopper-type filter, i.e., a single chopper may be provided with various kinds of filters 134. Accordingly, various specific single-wavelength flat uniform lights may be sensed by the detector 137 of the sensing unit 130.

[0064] In the case that the microfluidic chip 110 has at least two kinds of fluorescent nanoparticle-biomaterial composites, different fluorescence energies may be generated between a pair of the respective at least two kinds of fluorescent nanoparticle-bio-conjugated material composites. Thus, fluorescence energy for respective infectious diseases included in a biological sample may be generated.

[0065] A diagnostic apparatus for immunoassay according to embodiments of the inventive concept uses a fluorescence resonance energy transfer (FRET) effect between fluorescent nanoparticle-bio-conjugated material composites of the microfluidic chip 1 10 to improve detection limitation and sensitivity to an infectious disease included in a biological sample. Thus, the diagnostic apparatus may be applied to detect an infectious disease that exists at a considerably low concentration (<10^~ mol) in a biological sample of ultra small amount (10^~9~10^~12 /)·

[0066] In addition, a diagnostic apparatus for immunoassay according to embodiments of the inventive concept uses a fluorescence resonance energy transfer (FRET) effect between a plurality of kinds of fluorescent nanoparticle-bio-conjugated composites to qualitatively and quantitatively check whether respective infectious diseases included in the biological sample are infected and the infection degree of the respective infectious diseases on images at the same time. Thus, the diagnostic apparatus may be applied to qualitatively and quantitatively check a plurality of infectious diseases included in a biological sample at the same time.

[0067] In addition, a diagnostic apparatus for immunoassay according to embodiments of the inventive concept generates a fluorescence resonance energy transfer (FRET) effect between fluorescent nanoparticle-bio-conjugated material composites by using flat uniform light to collect and accumulate an electrical signal to two-dimensional type fluorescence energy. Thus, the diagnostic apparatus may be excellent in detection limitation and sensitivity and may not have need of darkroom conditions.

[0068] In addition, a diagnostic apparatus for immunoassay according to embodiments of the inventive concept utilizes a solar low power circuit as a power supply. Therefore, because the diagnostic apparatus does not need a separate external power supply, it may be manufactured as an easily transferable portable diagnostic apparatus.

[0069] While the inventive concept has been described with reference to exemplary embodiments, it will be apparent to those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the inventive concept. Therefore, it should be understood that the above embodiments are not limiting, but illustrative. Thus, the scope of the inventive concept is to be determined by the broadest permissible interpretation of the following claims and their equivalents, and shall not be restricted or limited by the foregoing description.

Claims

1. An apparatus for carrying out immunoassay.

2. The apparatus according to claim 1, comprising fluorescent nanoparticle-biomaterial

composite to detect biological species in a sample, a light source unit providing flat light to the apparatus to generate fluorescence energy caused by a fluorescence resonance energy transfer (FRET) effect between the fluorescent nanoparticle-biomaterial composite, a sensing unit configured to sense the fluorescence energy emitted from the apparatus, a measuring unit configured to convert the fluorescence energy sensed by the sensing unit into a current peak, a display unit configured to convert the current peak into an image, and a power supply unit to supply power required for operations of the light source unit, the sensing unit, the measuring unit, and the display unit, wherein if the biological species is present in the biological sample, the fluorescent nanoparticle-biomaterial composite is specifically bound to the biological species to form a fluorescent nanoparticle -bio-conjugated material composite.

3. The apparatus according to claim 2, which is a micro fluidic chip.

4. The apparatus according to claim 2, wherein the power supply is a solar low power circuit.

5. The apparatus according to claim 2, comprising at least two kinds of fluorescent nanoparticle- biomaterial composites.

6. The apparatus according to claim 2, wherein the fluorescent nanoparticle is metal

nanoparticle, quantum dot, organic nanoparticle, or lanthanide-based fluorescent nanoparticle.

7. The apparatus according to claim 6, wherein the metal nanoparticle is made of gold (Au), silver (Ag), copper (Cu), aluminum (Al), nickel (Ni), cobalt (Co), iron (Fe), zinc (Zn), or manganese (Mn) .

8. The apparatus according to claim 2, wherein the biomaterial is a composition comprising nucleic acid, amino acid, fat, glycoprotein, or antibody.

9. The apparatus according to claim 2, wherein the light source unit is a high-brightness light emitting diode (LED) and a light guide plate.

10. The apparatus according to claim 9, wherein the light source unit provides multi-wavelength flat uniform light.

1 1. The apparatus according to claim 2, further comprising an optical filter disposed between the light source unit and the apparatus to provide single-wavelength flat uniform light to the apparatus.

12. The apparatus according to claim 2, wherein the measuring unit converts two-dimensional type fluorescence energy sensed by the sensing unit into an electrical signal.

13. The apparatus according to claim 12, wherein the measuring unit accumulates electrical signal after converting the two-dimensional type fluorescence energy into electrical signal.

14. A method for detecting presence of a biological species in a biological sample comprising injecting a biological sample into the apparatus according to claim 2, having fluorescent nanoparticle-biomaterial composites such that the fluorescent nanoparticle-biomaterial composites are specifically bound to a biological species to form fluorescent nanoparticle- bio-conjugated material composites, providing flat uniform light to the microfluidic chip to generate fluorescence energy caused by a fluorescence resonance energy transfer (FRET) effect between the fluorescent nanoparticle-bio-conjugated material composites, collecting the fluorescence energy emitted from the apparatus, converting the collected fluorescence energy into an electrical signal, and converting the electrical signal into an image, presence of image indicates presences of the biological species in the biological sample.

15. The apparatus according to claim 14, which is a microfluidic chip.

16. The apparatus according to claim 14, wherein the power supply is a solar low power circuit.

17. The apparatus according to claim 14, comprising at least two kinds of fluorescent

nanoparticle-biomaterial composites.

18. The apparatus according to claim 14, wherein the fluorescent nanoparticle is metal

19. The apparatus according to claim 18, wherein the metal nanoparticle is made of gold (Au), silver (Ag), copper (Cu), aluminum (Al), nickel (Ni), cobalt (Co), iron (Fe), zinc (Zn), or manganese (Mn) .

20. The apparatus according to claim 14, wherein the biomaterial is a composition comprising nucleic acid, amino acid, fat, glycoprotein, or antibody.

21. The apparatus according to claim 14, wherein the light source unit is a high-brightness light emitting diode (LED) and a light guide plate.

22. The apparatus according to claim 21, wherein the light source unit provides multi- wavelength flat uniform light.

23. The apparatus according to claim 14, further comprising an optical filter disposed between the light source unit and the apparatus to provide single -wavelength flat uniform light to the apparatus.

24. The apparatus according to claim 14, wherein the measuring unit converts two-dimensional type fluorescence energy sensed by the sensing unit into an electrical signal.

25. The apparatus according to claim 23, wherein the measuring unit accumulates electrical

signal after converting the two-dimensional type fluorescence energy into electrical signal.