HIGH-SENSITIVE BIOSENSOR CHIP USING HIGH EXTINCTION COEFFICIENT MARKER AND DIELECTRIC SUBSTRATE, MEASUREMENT SYSTEM, AND MEASUREMENT METHOD

Abstract

The present chip relates to a high-sensitive biosensor chip using a high extinction coefficient marker and a dielectric substrate, a measurement system, and a measurement method and, more specifically, to an ellipsometry-based high-sensitive biosensor technology or a measurement method using same, the technology amplifying an elliptically polarized signal by a marker having a high extinction coefficient and a dielectric substrate. The marker and the substrate used in the present chip measure a Brewster's angle shift or an elliptical polarization measurement angle with respect to an ultra-low concentration biological material (e.g. antibody or DNA).

Claims

1. A highly sensitive biosensor chip using a marker having a large extinction coefficient and a dielectric substrate, the biosensor chip comprising: the dielectric substrate to which incident light is incident at a specific incident angle and is reflected from the dielectric substrate; an analyte section which is fixed on the substrate; and the marker that is bonded to the analyte section and amplifies an elliptical polarization signal.

2. The highly sensitive biosensor chip using a marker having a large extinction coefficient and a dielectric substrate according to claim 1, wherein the marker has an extinction coefficient which is equal to or larger than a specific value at light having a specific wavelength region.

3. The highly sensitive biosensor chip using a marker having a large extinction coefficient and a dielectric substrate according to claim 2, wherein the specific value k is 1.000.

4. The highly sensitive biosensor chip using a marker having a large extinction coefficient and a dielectric substrate according to claim 3, wherein the analyte section causes a surface of the dielectric substrate to function as a self-assembled thin film and fixes a capture antibody to the surface, and includes a detection antibody which attached to the marker and a biological bonding substance which is bonded between the detection antibody and the capture antibody and becomes an analysis target.

5. The haptic feedback fiber body of claim 4, further comprising a fixing fiber wound around the core fiber to fix the vibrating fibers fixed to the outer surface of the core fiber.

6. A highly sensitive measurement system using a marker having a large extinction coefficient and a dielectric substrate, the measurement system comprising: a polarization generating unit that generates polarized light; the biosensor chip according to claim 1 to which the polarized light generated at the polarization generating unit is incident at a specific incident angle; and a polarization detecting unit that measures a polarization signal from reflected light reflected from the biosensor chip.

7. The highly sensitive measurement system using a marker having a large extinction coefficient and a dielectric substrate according to claim 6, wherein the incident angle is Brewster's angle with respect to the dielectric substrate.

8. The highly sensitive measurement system using a marker having a large extinction coefficient and a dielectric substrate according to claim 6, wherein the incident angle is a maximum difference between a psi value of the dielectric substrate and a psi value of the marker.

9. The highly sensitive measurement system using a marker having a large extinction coefficient and a dielectric substrate according to claim 6, wherein the polarization generating unit includes a light source and a polarizer.

10. The highly sensitive measurement system using a marker having a large extinction coefficient and a dielectric substrate according to claim 6, wherein the polarization detecting unit includes an analyzer, a photodetector, and a calculation processor.

11. A highly sensitive measurement method using a marker having a large extinction coefficient and a dielectric substrate, the measurement method using the highly sensitive measurement system using a marker having a large extinction coefficient and a dielectric substrate according to claim 6, the measurement method comprising: a step of generating polarized light at a polarization generating unit; a step of causing the polarized light generated at the polarization generating unit to be incident to the biosensor chip at a specific incident angle; a step of amplifying a signal by the marker fixed to an analyte attached to the dielectric substrate; and a step of measuring a polarization signal from reflected light incident to the polarization detecting unit, after the reflected light is reflected from the biosensor chip.

12. The highly sensitive measurement method using a marker having a large extinction coefficient and a dielectric substrate according to claim 11, wherein the marker has an extinction coefficient k which is equal to or larger than 1.000 with light having a specific wavelength region.

13. The highly sensitive measurement method using a marker having a large extinction coefficient and a dielectric substrate according to claim 12, wherein a surface of the dielectric substrate is caused to function as a self-assembled thin film to fix a capture antibody to the surface, and a detection antibody which is attached to the marker and a biological bonding substance which is bonded between the detection antibody and the capture antibody and becomes an analysis target are provided.

Description

BRIEF DESCRIPTION OF DRAWINGS

[0039] The following drawings accompanied in this specification illustrate a preferred embodiment of the present invention and are provided to cause the technical idea of the present invention to be better understood with the detailed description of the invention, and thus the present invention is not to be understood by being limited only to illustration of the drawings.

[0040] FIG. 1 is a configurational diagram of a measurement system using a biosensor according to an embodiment of the present invention.

[0041] FIG. 2 is a schematic diagram of a highly sensitive biosensor chip using a marker having a large extinction coefficient and a dielectric substrate according to the embodiment of the present invention.

[0042] FIG. 3 is a graph illustrating amplification of an elliptical polarization signal by the marker according to the embodiment of the present invention.

[0043] FIGS. 4 and 5 are a refractive index and extinction coefficient table of a candidate substance classified in accordance with a criterion for selecting a marker having a large extinction coefficient according to the embodiment of the present invention.

[0044] FIG. 6 is a graph illustrating amplification of an elliptical polarization signal when a dielectric substrate and an Ru marker are applied.

[0045] FIG. 7 illustrates graphs indicating a dielectric substrate signal, and a marker signal depending on a marker according to the embodiment of the present invention, a signal amplification degree.

[0046] FIG. 8 is a graph illustrating amplification of an elliptical polarization signal depending on the marker according to the embodiment of the present invention.

[0047] FIGS. 9 and 10 illustrate comparison of elliptical polarization signals depending on a thickness of a marker (for example, SiO.sub.2) having a small extinction coefficient in a specific wavelength region in order to check a signal amplification effect according to the embodiment of the present invention.

DESCRIPTION OF EMBODIMENTS

[0048] The objects, other objects, characteristics, and advantages of the present invention described above are to be easily understood through the following preferred embodiments related to the accompanying drawings. However, the present invention is not limited to the embodiments described here and can be realized as other embodiments. Instead, the embodiments introduced here are provided to make the disclosed details thorough and complete and to allow ideas of the present invention to be sufficiently understood by those skilled in the art.

[0049] In this specification, a case where a certain configurational element is described to be present on another configurational element means a case where the configurational element can be directly formed on the other configurational element or a third configurational element can be interposed between the configurational elements. In addition, in the drawings, configurational elements are illustrated to have an enlarged thickness for effective description of the technical details.

[0050] The embodiments described in this specification are to be described with reference to cross-sectional views and/or plan views which are ideally illustrated views of the present invention. In the drawings, films and regions are illustrated to have an enlarged thickness for effective description of the technical details. Consequently, a shape in an illustrated view can be changed due to a manufacturing technology, a tolerance, and/or the like. Consequently, the embodiments of the present invention are not limited to specific shapes illustrated in the drawings but include a change in shape which occurs according to a manufacturing process. For example, a region illustrated to have a right angle can have a shape which is rounded or has predetermined curvature. Consequently, regions illustrated in the drawings have a property, and shapes of the regions illustrated in the drawings are provided to illustrate specific shapes of regions of an element and are not provided to limit a scope of the invention. In various embodiments in this specification, terms of first, second, and the like are used to describe various configurational elements; however, the configurational elements are not to be limited by these terms. These terms are used only to distinguish a certain configurational element from another configurational element. The embodiments described and illustrated here also include complementary embodiments thereof.

[0051] Terms used in this specification are used to describe embodiments and are not used to limit the present invention. In this specification, a singular form includes meaning of a plural form unless otherwise described particularly in the description. When terms such as comprises and/or comprising is used in the specification, a mentioned configurational element does not exclude presence or addition of one or more other configurational elements.

[0052] In the description of the following specific embodiments, several specific details are provided to more specifically describe the invention and to gain a better understanding of the invention. However, a reader who has knowledge in the art to understand the present invention can recognize that the present invention can be used without these several specific details. The following is mentioned in advance. In some cases, parts which are commonly known but are not closely related to the invention in a description of invention are not described in order to prevent confusion from being caused for no good reason in the description of the present invention.

[0053] Hereinafter, a highly sensitive measurement system 100 using a marker having a large extinction coefficient and a dielectric substrate according to an embodiment of the present invention is basically configured to include a highly sensitive biosensor chip 20 using a marker having a large extinction coefficient and a dielectric substrate.

[0054] First, FIG. 1 illustrates a configurational diagram of the measurement system 100 using the biosensor chip 20 according to an embodiment of the present invention. As illustrated in FIG. 1, the measurement system 100 according to the embodiment of the present invention is configured to include a polarization generating unit 10 that generates polarized light; the biosensor chip 20 to which the polarized light generated at the polarization generating unit 10 is incident at a specific incident angle and which amplifies an elliptical polarization signal; and a polarization detecting unit 30 that measures the elliptical polarization signal from reflected light reflected from the biosensor chip 20. In other words, in the embodiment of the present invention, a technology for amplifying a signal by an ellipsometric biosensor using a dielectric substrate 21 and a marker having a large extinction coefficient is described. In order to realize the embodiment, a short wavelength ellipsometer configured to include a light source 11, a polarizer 12, a sample piece, an analyzer 31, and a measuring instrument is used.

[0055] The polarization generating unit 10 according to the embodiment of the present invention generates polarized light and can have the light source 11 and the polarizer 12.

[0056] Examples of the light source 11 can include various types of lamps which emit monochromatic light or white light having infrared, visible light, or ultraviolet wavelength ranges, a semiconductor laser diode (LD) including a light-emitting diode (LED), a solid-, liquid-, or gas-state laser, and a laser diode, and the like. In addition, the light source 11 can have a structure which can vary a wavelength depending on a structure of an optical system. Besides, the polarizer 12 can be configured to be rotatable, or another polarization modulating means can be further provided.

[0057] Besides, the polarization detecting unit 30 is to measure an elliptical polarization signal from the reflected light reflected from the biosensor chip 20. In other words, the polarization detecting unit receives the reflected light and detects a polarization change thereof. The polarization detecting unit 30 includes the analyzer 31 and a measurement unit 32, and the measurement unit 32 can include a detector, a calculation processor, and the like. In addition, a compensator and a spectroscope can be provided.

[0058] The analyzer 31 corresponds to the polarizer 12 and have a polarizing plate to re-polarize reflected light, thereby, being capable of controlling a degree of polarization of the reflected light or a direction of a polarization plane. The analyzer 31 can be configured to be rotatable according to a structure of an optical system, or another polarization modulating means that can perform a function of a phase change or removal of a polarization component can be further provided.

[0059] The detector fulfills a function of detecting polarized reflected light to obtain optical data and converting the optical data into an electrical signal. In this case, the optical data contains information about a change in polarization state of the reflected light. An example of the detector can include a CCD-type solid imaging element, a photomultiplier tube (PMT), or a silicon photodiode.

[0060] The calculation processor acquires an electrical signal from the detector and derives a measured value. The calculation processor has a predetermined analysis program using a reflectivity measuring method and ellipsometry which is installed to cause the calculation processor to extract and analyze the optical data converted into the electrical signal, thereby deriving a measured value such as an adsorption concentration of a sample, a thickness of an adsorption layer, an adsorption constant, a dissociation constant, or a refractive index. In this case, it is preferable that the calculation processor derives the measured value by obtaining ellipsometric constants and related to a phase difference of the ellipsometry in order to improve measurement sensitivity.

[0061] FIG. 2 is a schematic diagram of the highly sensitive biosensor chip 20 using a marker having a large extinction coefficient and a dielectric substrate according to the embodiment of the present invention. In addition, FIG. 3 is a graph illustrating amplification of an elliptical polarization signal by a marker 26 according to the embodiment of the present invention. In other words, FIG. 2 is a diagram illustrating a technical concept of amplification of the elliptical polarization signal. The drawing indicates that the dielectric substrate 21 and the marker 26 having a large extinction coefficient are used to amplify the elliptical polarization signal of the ellipsometric biosensor chip 20.

[0062] The biosensor chip 20 according to the embodiment of the present invention uses the dielectric substrate 21, and the biosensor chip 20 is manufactured by fixing a biological bonding substance (for example, capture antibody or genome) to a surface of the dielectric substrate. An analyte in a biological sample is reacted and bonded with the biological bonding substance fixed to a sensor surface, and the marker 26 having a large extinction coefficient is attached to a detection substance 23 (for example, detection antibody or genome) and generates a high elliptical polarization signal with respect to the analyte.

[0063] In this case, as the marker 26, a marker 26 (k >1.000) having a large extinction coefficient at light having a specific wavelength region is used. In addition, an angle at which a laser beam is incident to the dielectric substrate 21 can be determined by basically applying the Brewster's angle with respect to the dielectric substrate 21 and also can be set to a specific incident angle at which a difference between a psi value of the dielectric substrate 21 and a psi value of the marker 26 is the largest.

[0064] As illustrated in FIG. 2, the highly sensitive biosensor chip 20 using the marker 26 having a large extinction coefficient and the dielectric substrate 21 according to the embodiment of the present invention is configured to include the dielectric substrate 21 to which incident light is incident at a specific incident angle and is reflected from the dielectric substrate; an analyte section 22 which is fixed on the substrate 21; and the marker 26 having a large extinction coefficient which is bonded to the analyte section 22 and amplifies an elliptical polarization signal.

[0065] The analyte section 22 according to the embodiment causes a surface of the dielectric substrate 21 to function as a self-assembled thin film and fixes a capture antibody 25 to the surface, and includes a detection antibody 23 which is attached to the marker 26 and a biological bonding substance 24 which is bonded between the detection antibody 23 and the capture antibody 25 and becomes an analysis target. Examples of the biological bonding substance 24 can include protein, DNA, RNA, a cell, a peptide, a bacterium, and the like.

[0066] In other words, as illustrated in FIG. 2, the surface of the dielectric substrate 21 is caused to function as a self-assembled thin film, and fix the capture antibody 25. The detection antibody 23 can be attached to the marker 26 having a large extinction coefficient, and the marker can induce a sandwich bonding reaction with the target substance. In this case, the marker 26 having a large extinction coefficient which is formed at the dielectric substrate 21 amplifies the elliptical polarization signal (psi, ) by causing a large change in refractive index based on the specific incident angle (for example, Brewster's angle).

[0067] Besides, the marker 26 has an extinction coefficient which is equal to or larger than a specific value at light having a specific wavelength region. In the embodiment of the present invention, the specific value k corresponds to 1.000.

[0068] FIGS. 4 and 5 are a refractive index and extinction coefficient table of a candidate substance classified in accordance with a criterion for selecting the marker 26 having a large extinction coefficient according to the embodiment of the present invention.

[0069] In other words, FIGS. 4 and 5 provide the criterion for selecting the marker 26 having a large extinction coefficient k. In the embodiment of the present invention, a mineral property of the marker 26 with respect to a specific wavelength (532 nm) is classified as a complex refractive index containing the refractive index and the extinction coefficient. The marker 26 is selected particularly based on the extinction coefficient k larger than 1.000. Individual candidate substances of the marker have a different extinction coefficient depending on a wavelength of the light source 11; however, the criterion of the extinction coefficient for selecting the marker 26 is the same even at a light source 11 having a different wavelength.

[0070] FIG. 6 is a graph illustrating amplification of the elliptical polarization signal when the dielectric substrate 21 and an Ru marker 26 are applied. FIG. 7 illustrates graphs indicating a dielectric substrate signal, a marker (26) signal depending on the marker 26 according to the embodiment of the present invention, and a signal amplification degree. In addition, FIG. 8 is a graph illustrating amplification of an elliptical polarization signal depending on the marker 26 according to the embodiment of the present invention.

[0071] In other words, FIG. 6 illustrates a psi value of a signal amplification degree estimated at a specific incident angle (for example, incident angle of 45) when the marker 26 having a large extinction coefficient is bonded by 0.1 nm at the dielectric substrate 21. According to the embodiment of the present invention, signal amplification due to a size of the marker 26 is not used, but a mineral property of the marker 26 having a large extinction coefficient which causes a large change in refractive index with the dielectric substrate 21 is used, and thus the elliptical polarization signal is largely amplified even with a size having a nanometer or smaller. That enables a signal to be amplified 100 times than a signal from the silicon marker 26 of 0.1 nm having a silicon oxide film.

[0072] FIGS. 9 and 10 illustrate comparison of elliptical polarization signals depending on a thickness of a marker (for example, SiO.sub.2) having a small extinction coefficient at a specific wavelength region in order to check a signal amplification effect according to the embodiment of the present invention. As a result, the following is confirmed. As illustrated in FIGS. 9 and 10, when a marker having a low extinction coefficient is bonded by 2 nm or larger to the sensor surface, the elliptical polarization signal is increased to 0.5000 psi or larger. That can be an indication of obtaining an elliptical polarization signal lower than 100 times the signal by the marker 26 having a large extinction coefficient provided in the embodiment of the present invention.

[0073] In addition, the device and method described above can have a configuration in which all or a part of individual embodiments are selectively combined such that the configurations and methods of the embodiments described above are not to be limitedly applied, but the above-described embodiments can be variously modified.