Terahertz guided-mode resonance resonator and rapid PCR detection system and method

Abstract

The invention provides a terahertz guided-mode resonance resonator and a rapid PCR detection system and method.The terahertz guided-mode resonance resonator comprises a substrate and a metal grating structure arranged on the substrate, the substrate comprises a first substrate and a second substrate which are parallel to each other, and a cavity is formed between the first substrate and the second substrate; the metal grating structure comprises two layers of metal gratings formed by periodically arranging the same metal, and the two layers of metal gratings are respectively arranged on the outer surfaces of the first substrate and the second substrate; the invention has the following beneficial effects: the terahertz technology is combined with the guided-mode resonance resonator technology, and rapid melting of RNA base fragments is realized through terahertz waves transmitted by the terahertz wave transmitting module; and the unlinking process is detected by utilizing the resonance coupling effect of light observed by a terahertz probe in the terahertz guided-mode resonance resonator and the terahertz detection module and the resonator, so that rapid PCR detection is realized, and the PCR detection speed and accuracy are remarkably improved.

Description

Technical Field

[0001] The present invention relates to the technical field of terahertz band detection, and in particular to a terahertz guided mode resonance resonator and a rapid PCR detection system and method. Background Art

[0002] Polymerase chain reaction (PCR) technology is a molecular biology technology used to amplify specific DNA fragments. Its basic principle is to use DNA polymerase to achieve rapid amplification of target DNA sequences through cyclic replication reactions under high temperature conditions. Classic PCR usually goes through three stages: high temperature denaturation, annealing, and extension. During high temperature denaturation, the reaction mixture is heated to 94-98 degrees Celsius (usually 95 degrees Celsius). Such a high temperature causes the hydrogen bonds between the double DNA strands to break, thereby unwinding the DNA double helix structure and forming two single-stranded DNAs. The reaction mixture then undergoes an annealing step, where the temperature is lowered to 50-65 degrees Celsius to allow primers to specifically bind to the single-stranded DNA template. The last step is an extension step, where the temperature is usually around 72 degrees Celsius, at which time DNA polymerase (such as Taq polymerase) begins to synthesize new DNA chains.

[0003] This process is repeated for multiple cycles, and each cycle doubles the number of target DNA sequences, resulting in an exponential increase in the number of target DNA fragments. Since the process is simple to operate, has a fixed procedure, and has low technical requirements, PCR technology is widely used in environmental monitoring, food safety, medical diagnosis and other fields. However, since it operates at high temperatures, it is limited in terms of accuracy of the results, detection time, and detection cost. For example, high-temperature denaturation can cause non-specific unwinding of DNA, resulting in false positive results. High-temperature denaturation may cause oxidation and damage to DNA, which may affect the accuracy and stability of PCR. High-temperature denaturation requires precise temperature control, which increases the cost and complexity of the experiment. The requirements for nucleic acid detection capabilities and efficiency are constantly increasing, so it is crucial to achieve fast and accurate PCR detection.

[0004] Terahertz spectroscopy has the characteristics of non-contact, label-free, broadband detection, and it has been found that the vibration and rotation energy levels of many biological molecules are just within the terahertz band; recently, studies have found that RNA base fragments have absorption peaks in the terahertz band and will melt rapidly under terahertz irradiation. Therefore, using terahertz lasers to irradiate DNA molecules instead of high-temperature denaturation processes can make the molecules unwind at lower temperatures, which will not cause damage to the human body and DNA molecules, and can shorten the unwinding time, and has broad application space in the fields of scientific research and medical detection; in addition, since RNA base fragments have absorption peaks in the terahertz band, the coupling effect of terahertz waves and molecules can be enhanced by designing suitable optical resonators, and terahertz probes can be used to achieve fast and accurate PCR detection; in summary, the introduction of terahertz waves to accelerate DNA unwinding can achieve a fast, efficient and accurate technology for PCR detection using optical resonators and terahertz probes. Summary of the invention

[0005] In view of the above-mentioned shortcomings of the prior art, an object of the present invention is to provide a terahertz guided mode resonance resonator and a rapid PCR detection system and method, so as to solve the problem that the existing PCR detection technology not only has low detection efficiency but also has low accuracy of detection results.

[0006] In order to achieve the above-mentioned purpose and other related purposes, the present invention provides the following technical solutions:

[0007] A terahertz guided mode resonance resonator comprises a substrate and a metal grating structure arranged on the substrate, wherein the substrate comprises a first substrate and a second substrate parallel to each other, a cavity is formed between the first substrate and the second substrate, the metal grating structure comprises two layers of metal gratings composed of a periodic arrangement of the same metal, and the two layers of the metal gratings are respectively arranged on the outer surfaces of the first substrate and the second substrate. The terahertz guided mode resonance resonator in the technical solution can enhance the coupling effect between terahertz waves and molecules, thereby facilitating the terahertz probe in a subsequent terahertz detection module to achieve rapid and accurate PCR detection.

[0008] In one embodiment of the present invention, the first substrate and the second substrate are connected to each other through a bracket, the distance between the first substrate and the second substrate can be adjusted by a screw micrometer, and the metal grating on the first substrate and the metal grating on the second substrate are offset from each other by N periods.

[0009] In one embodiment of the present invention, the materials used for the first substrate and the second substrate include but are not limited to one or more of single crystal silicon, quartz and polyethylene, and the material used for the metal grating structure includes but is not limited to one of gold, silver, copper and aluminum. The material used for the metal grating structure in this technical solution is a metasurface, so the present invention combines terahertz technology with the metasurface, thereby realizing fast and accurate PCR detection.

[0010] A rapid PCR detection system using the terahertz guided mode resonance resonator, the rapid PCR detection system comprising a microfluidic emission module, a terahertz wave emission module, a plurality of the terahertz guided mode resonance resonators and a terahertz detection module which are sequentially placed on the same optical axis, a microfluidic molecular channel is formed between the emission port of the microfluidic emission module and the detection end of the terahertz detection module, and the length of the microfluidic molecular channel includes and is greater than the length of the cavity.

[0011] In one embodiment of the present invention, the spectral range of the terahertz wave transmitting module and the spectral range of the terahertz detection module include and are greater than the operating frequency range of the terahertz guided mode resonance resonator.

[0012] A rapid PCR detection method using the terahertz guided mode resonance resonator, the rapid PCR detection method comprising the following steps: taking a clean and complete terahertz guided mode resonance resonator, and using the terahertz detection module to measure its terahertz transmission spectrum, and recording the terahertz transmission spectrum of the terahertz guided mode resonance resonator; fixing the terahertz guided mode resonance resonator on a sample rack according to polarization direction requirements, taking a sample solution to be tested and flowing it into the cavity of the terahertz guided mode resonance resonator through a microfluidic emission module using a microfluidic molecular channel;

[0013] The terahertz wave emitted by the terahertz wave emission module is used to irradiate the sample to be tested in the cavity of the terahertz guided mode resonance resonator, so as to quickly unzip the sample to be tested in the cavity; the terahertz transmission spectrum thereof is measured by the terahertz detection module, the terahertz transmission spectrum with the information of the sample to be tested is read, and the terahertz transmission spectrum with the information of the sample to be tested is recorded.

[0014] As described above, a terahertz guided mode resonance resonator and a rapid PCR detection system and method of the present invention have the following beneficial effects: the present invention combines terahertz technology with resonator resonance technology, realizes rapid unzipping of RNA base fragments through terahertz waves emitted by a terahertz wave emission module, and utilizes the resonant coupling effect of light observed by the terahertz guided mode resonance resonator and the terahertz probe in the terahertz detection module and the resonator to detect the unzipping process, realizes rapid PCR detection, and significantly improves the PCR detection speed and accuracy. Therefore, the present invention realizes rapid detection of PCR detection, is applied to various types of molecular detection and diagnosis, and has good application prospects in the fields of genetic research, medical examination, epidemiological detection, tumor treatment, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a three-dimensional schematic diagram of a terahertz guided mode resonance resonator in a first embodiment of the present invention;

[0016] Figure 2 Shown is a three-dimensional schematic diagram of a rapid PCR detection system in a second embodiment of the present invention;

[0017] Figure 3 Shown is a schematic diagram of the process of the rapid PCR detection method in the third embodiment of the present invention;

[0018] Figure 4 Shown is a schematic diagram of the resonance peak of the terahertz guided mode resonance resonator designed for the new coronavirus in the present invention;

[0019] Figure 5 Shown is a schematic diagram of the detection results of the terahertz guided mode resonance resonator of the present invention for the new coronavirus.

[0020] Component number description

[0021] 1. Terahertz guided mode resonant resonator; 101. substrate; 1011. first substrate; 1012. second substrate; 102. metal grating structure; 1021. metal grating; 103. cavity; 2. microfluidic emission module; 3. terahertz wave emission module; 4. terahertz detection module; 5. microfluidic molecular channel. DETAILED DESCRIPTION

[0022] The following specific embodiments illustrate the implementation of the present invention, and those familiar with the technology can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. It should be noted that the following embodiments and features in the embodiments can be combined with each other without conflict.

[0023] Based on the problems that the PCR detection technology existing in the background technology has long time consumption, low accuracy and high detection cost, the present invention combines terahertz technology with guided mode resonance resonator to achieve fast and accurate PCR detection.

[0024] PCR technology is a molecular biology technology used to amplify specific DNA fragments. Its basic principle is to use DNA polymerase under high temperature conditions to achieve rapid amplification of target DNA sequences through a cyclic replication reaction. Classic PCR usually goes through three stages: high temperature denaturation, annealing, and extension. Due to the simple operation and fixed procedures of the process and low technical requirements, PCR technology is widely used in environmental monitoring, food safety, medical diagnosis and other fields. However, due to the high temperature operation, the accuracy of the results, detection time and detection cost are limited.

[0025] Terahertz waves are a special band between microwaves and infrared, and are highly sensitive to low-frequency fingerprint information such as lattice vibrations and intermolecular interactions, which gives terahertz spectroscopy technology unique advantages in molecular detection. The combination of terahertz waves and guided mode resonance resonators can make full use of the characteristics of terahertz waves such as rich fingerprint information and coherent physical parameters, as well as the advantages of rich electromagnetic modes in optical resonators, and has been widely used in fields such as biological detection.

[0026] See also Figure 1 The first embodiment of the present invention relates to a terahertz guided mode resonator, comprising a substrate 101 and a metal grating structure 102 attached to the surface of the substrate 101, wherein the metal grating structure 102 is deposited on the surface of the substrate 101 by photolithography technology, the substrate 101 comprises a first substrate 1011 and a second substrate 1012 which are parallel to each other, a cavity 103 is formed between the first substrate 1011 and the second substrate 1012, the first substrate 1011 and the second substrate 1012 are connected to each other by a bracket, the distance between the first substrate 1011 and the second substrate 1012 can be adjusted by a screw micrometer, the materials used by the first substrate 1011 and the second substrate 1012 include but are not limited to one or more of single crystal silicon, quartz and polyethylene, and single crystal silicon, quartz, polyethylene, etc. are materials with good transmittance in the terahertz band;

[0027] The metal grating structure 102 includes two layers of metal gratings 1021 composed of a periodic arrangement of the same metal. The two layers of metal gratings 1021 are respectively arranged on the outer surfaces of the first substrate 1011 and the second substrate 1012, and the metal gratings 1021 on the first substrate 1011 and the metal gratings 1021 on the second substrate 1012 are offset from each other by N periods. The material used by the metal grating structure 102 includes but is not limited to one of gold, silver, copper and aluminum, wherein the relative width and period of the metal gratings 1021 are variable. In this embodiment, the metal gratings 1021 on the first substrate 1011 and the metal gratings 1021 on the second substrate 1012 are offset from each other by half a period; by adjusting the distance between the first substrate 1011 and the second substrate 1012, the width of the metal gratings 1021 and the period of the metal gratings 1021, rapid detection of PCR is achieved, and by adjusting the structural parameters and materials of the terahertz guided mode resonance resonator 1, Fabry-Perot interference can be excited to achieve terahertz resonance with a high Q value.

[0028] See also Figure 2 The second embodiment of the present invention relates to a rapid PCR detection system using the terahertz guided mode resonance resonator, the rapid PCR detection system comprises a microfluidic emission module 2, a terahertz wave emission module 3, a plurality of terahertz guided mode resonance resonators 1 and a terahertz detection module 4 which are sequentially placed on the same optical axis, a microfluidic molecular channel 5 is formed between the emission port of the microfluidic emission module 2 and the detection end of the terahertz detection module 4, the length of the microfluidic molecular channel 5 includes and is greater than the length of the cavity 103, the spectral range of the terahertz wave emission module 3 and the spectral range of the terahertz detection module 4 include and are greater than the operating frequency range of the terahertz guided mode resonance resonator 1, wherein, in this embodiment, the microfluidic emission module 2 is a microfluidic emitter, the terahertz wave emission module 3 is a terahertz wave emitter, and the terahertz detection module 4 uses a terahertz probe for detection, and the rapid PCR detection system also comprises a data processing and display module, the data processing and display module is used to process, record and display the terahertz transmission spectrum of the terahertz guided mode resonance resonator 1 and the terahertz transmission spectrum of the sample to be tested.

[0029] See also Figure 3The third embodiment of the present invention relates to a rapid PCR detection method using the terahertz guided mode resonance resonator, and the rapid PCR detection method comprises the following steps: S1: taking a clean and complete terahertz guided mode resonance resonator 1, and using the terahertz detection module 4 to measure its terahertz transmission spectrum, and recording the terahertz transmission spectrum of the terahertz guided mode resonance resonator 1, that is, the resonance frequency; S2: fixing the terahertz guided mode resonance resonator 1 on the sample holder according to the polarization direction requirements, taking the sample solution to be tested through the microfluidic emission Module 2 uses the microfluidic molecular channel 5 to flow into the cavity 103 of the terahertz guided mode resonance resonator 1; S3: uses the terahertz wave emitted by the terahertz wave emission module 3 to irradiate the sample to be tested in the cavity 103 of the terahertz guided mode resonance resonator 1, so as to quickly unzip the sample to be tested in the cavity 103; S4: uses the terahertz detection module 4 to measure its terahertz transmission spectrum, reads the terahertz transmission spectrum with the information of the sample to be tested, and records the terahertz transmission spectrum with the information of the sample to be tested, so as to quickly complete the PCR detection;

[0030] There is also a rapid PCR detection method using the terahertz guided mode resonance resonator that can be briefly described as the following steps: because when the terahertz guided mode resonance resonator 1 is produced, its resonance frequency is 13.8 THz, that is, its terahertz transmission spectrum is determined after the production is completed, so the first step can be omitted; first, the microfluidic emission module 2 is used to make the sample solution to be tested flow into the cavity 103 of the terahertz guided mode resonance resonator 1, and the terahertz guided mode resonance resonator 1 is fixed on the sample rack; then the terahertz wave is introduced to irradiate the sample to be tested for rapid unzipping, and the terahertz wave is generated by the terahertz wave emission module 3, vertically incident and passes through the terahertz guided mode resonance resonator 1 loaded with the sample to be tested, and is finally detected by the terahertz detection module 4, and an obvious terahertz resonance peak reference signal will appear, thereby quickly completing the PCR detection.

[0031] In practical applications, the present invention is described in detail by taking the novel coronavirus PCR detection as an example. Figure 4 The resonance peak of the terahertz guided mode resonance resonator 1 designed for the detection of the new coronavirus. Figure 5The terahertz guided mode resonant resonator detects the PCR result of the novel coronavirus; in the present embodiment, the material of the substrate 101 of the terahertz guided mode resonant resonator 1 is single crystal silicon, with a thickness of 2.5 μm and a square shape of 20×20 μm. The material of the substrate 101 can also be replaced by other materials with good transmittance in the terahertz band; the metal grating 1021 is composed of a combination of gold sheets, the thickness of the gold sheets is 60 nm, and the shape of a rectangle with a side length of 20×2.5 μm. The metal grating 1021 is deposited on both sides of the substrate 101 by a photolithography process, and the material of the metal grating 1021 can also be replaced by other metal materials; the output frequency of the terahertz wave transmitting module 3 is a 10-15 THz signal, and the detection frequency of the terahertz detection module 4 is a 10-15 THz signal;

[0032] The virus PCR detection method is specifically as follows: the first step is to take a clean and complete terahertz guided mode resonance resonator 1, fix it on the sample holder as required, and use the terahertz detection module 4 to measure its transmission spectrum. At this time, the resonant frequency of the terahertz guided mode resonance resonator 1 is at 13.8 THz, such as Figure 4 As shown; the second step is to take 10 μL of the new coronavirus sample and flow it into the cavity 103 of the terahertz guided mode resonance resonator 1 through the microfluidic emission module 2; the third step is to fix the terahertz guided mode resonance resonator 1 loaded with the new coronavirus sample in the cavity 103 on the sample rack again, and use the terahertz wave emitted by the terahertz wave emission module 3 to quickly unzip; the fourth step is to use the terahertz detection module 4 to measure its transmission spectrum and detect the unzipping process in the virus sample, so as to determine whether it is fully unzipped or half unzipped.

[0033] In summary, the present invention combines terahertz technology with resonator resonance technology, realizes rapid unzipping of RNA base fragments through the terahertz wave emitted by the terahertz wave emission module 3, and utilizes the resonant coupling effect of the light observed by the terahertz probe in the terahertz guided mode resonance resonator 1 and the terahertz detection module 4 and the resonator to detect the unzipping process, thereby realizing rapid PCR detection and significantly improving the PCR detection speed and accuracy. Therefore, the present invention realizes rapid detection of PCR detection and is applied to various molecular detection and diagnosis, and has good application prospects in the fields of genetic research, medical examination, epidemiological detection, tumor treatment, etc.; and the terahertz guided mode resonance resonator 1 in the present invention has the characteristics of being simple to use, reusable, and adaptable to various terahertz detection systems, and is easy to operate, with a processing accuracy of only micrometer level, a mature production process, and low cost, and can be mass-produced, with good commercial application potential.

[0034] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. All equivalent modifications or changes made by those skilled in the art without departing from the spirit and technical ideas disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. A terahertz guided mode resonance resonator, characterized in that: The invention comprises a substrate (101) and a metal grating structure (102) arranged on the substrate (101), wherein the substrate (101) comprises a first base (1011) and a second base (1012) which are parallel to each other, a cavity (103) is formed between the first base (1011) and the second base (1012), and the metal grating structure (102) comprises two layers of metal gratings (1021) composed of a periodic arrangement of the same metal, and the two layers of the metal gratings (1021) are respectively arranged on the outer surfaces of the first base (1011) and the second base (1012).

2. A terahertz guided mode resonance resonator according to claim 1, characterized in that: The first substrate (1011) and the second substrate (1012) are connected to each other via a bracket, the distance between the first substrate (1011) and the second substrate (1012) can be adjusted by a screw micrometer, and the metal grating (1021) on the first substrate (1011) and the metal grating (1021) on the second substrate (1012) are offset from each other by N periods.

3. The terahertz guided mode resonance resonator according to claim 1, characterized in that: The materials used for the first substrate (1011) and the second substrate (1012) include, but are not limited to, one or more of single crystal silicon, quartz and polyethylene, and the material used for the metal grating structure (102) includes, but is not limited to, one of gold, silver, copper and aluminum.

4. A rapid PCR detection system using the terahertz guided mode resonance resonator according to claim 1, characterized in that: The rapid PCR detection system comprises a microfluidic emission module (2), a terahertz wave emission module (3), a plurality of terahertz guided mode resonance resonators (1) and a terahertz detection module (4) which are sequentially placed on the same optical axis; a microfluidic molecular channel (5) is formed between the emission port of the microfluidic emission module (2) and the detection end of the terahertz detection module (4); the length of the microfluidic molecular channel (5) includes and is greater than the length of the cavity (103).

5. The rapid PCR detection system using the terahertz guided mode resonance resonator according to claim 4, characterized in that: The spectral range of the terahertz wave emission module (3) and the spectral range of the terahertz detection module (4) include and are greater than the operating frequency range of the terahertz guided mode resonance resonator (1).

6. A rapid PCR detection method using the terahertz guided mode resonance resonator of claim 1, characterized in that: The rapid PCR detection method comprises the following steps: Taking a clean and complete terahertz guided mode resonance resonator (1), and using the terahertz detection module (4) to measure its terahertz transmission spectrum, and recording the terahertz transmission spectrum of the terahertz guided mode resonance resonator (1); The terahertz guided mode resonance resonator (1) is fixed on a sample rack according to polarization direction requirements, and a sample solution to be tested is taken and flows into the cavity (103) of the terahertz guided mode resonance resonator (1) through a microfluidic emission module (2) and a microfluidic molecular channel (5); Using the terahertz wave emitted by the terahertz wave emission module (3) to irradiate the sample to be tested in the cavity (103) of the terahertz guided mode resonance resonator (1), thereby quickly unzipping the sample to be tested in the cavity (103); The terahertz detection module (4) is used to measure the terahertz transmission spectrum, read the terahertz transmission spectrum with the information of the sample to be tested, and record the terahertz transmission spectrum with the information of the sample to be tested.

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