TWI742373B - Self-heating biosensor based on lossy mode resonance and, sensing system, methods of using the same - Google Patents

Abstract

A self-heating biosensor based on lossy mode resonance (LMR) includes a waveguide unit and a lossy mode resonance layer. The waveguide unit is a flat plate, including two planes and at least two sets of opposite sides. One set of the opposite sides of the waveguide unit has a light input end and a light output end. The lossy mode resonance layer is disposed on one of the planes of the waveguide unit. Two heating electrodes are formed at two positions of the lossy mode resonance layer, and a biomaterial sensing region having a boride bioprobe is formed between the two heating electrodes. The two positions are relevant to one set of the opposite sides of the waveguide unit. The present disclosure further includes a using method relevant to the self-heating biosensor based on lossy mode resonance.

Description

Self-heating biosensor and sensing system based on loss modal resonance And how to use it

The present invention relates to a biological sensor, especially a biological sensor based on the principle of lossy mode resonance (LMR) and having a self-heating function.

In the current life, human life styles are changing with the development of the country and society. In the era of rapid technological development and convenient medical services, many countries have never developed into developing or developed countries and enjoy the benefits of technology. The convenience of China is no longer a dream, and the distance between countries is no longer a distance, regardless of industry, information, culture and food. With the convenience and longevity of life, civilization diseases have also arisen, such as heart disease, cancer, obesity and diabetes. Take diabetes as an example. Its main feature is that the patient's blood sugar is higher than the standard value for a long time. Normally, when the human blood sugar rises, insulin should be used to control the blood sugar to lower it. In diabetes testing, glycosylated hemoglobin (HbA1c) can be used as the basis for blood glucose status in the past 3 months.

In the past few years of biological detection technology, surface plasmon resonance (SPR) technology has made great progress, and its high sensitivity makes it It can be widely used in the fields of biology and chemistry for molecular level detection. In many research work, the sensor type of surface plasmon resonance (SPR) technology is constructed by using a high refractive index prism coated with a metal layer on the surface, and the incident angle of light can be in a wide range. Therefore, any change between the medium and the object to be measured can find a suitable angle to excite the surface plasma, and the incident light will have total internal reflection (TIR) at the junction of the optical waveguide and the resonant film and generate evanescent waves. (evanescent wave). Among them, the incident light includes transverse electronic (TE) waves and transverse magnetic (TM) waves. Surface plasmon resonance (SPR) technology can only be excited by TM waves. Regarding the choice of metal thin film materials, surface plasmon resonance components usually use precious metal materials such as gold and silver for better results, but the disadvantage is that the material is expensive and is easy to oxidize for a long time. In addition, the sensor architecture using the prism design usually has a huge volume, requiring expensive optical equipment (such as lens sets) and precision mechanical equipment assistance (such as air-cushioned optical shock-proof equipment), and it is not easy to achieve miniaturization and products. Mass production. Biological or chemical reactions are greatly affected by temperature. There is a stable temperature and humidity control in the laboratory, which is not a big problem, but it is usually necessary to have stable temperature control outdoors. However, the current SPR or LMR components cannot perform temperature control. .

For this reason, how to design a biological sensor to solve the aforementioned technical problems is an important subject studied by the inventors of this case.

The purpose of the present invention is to provide a self-heating biosensor based on loss modal resonance, which can achieve the purpose of low cost, miniaturization and easy operation.

To achieve the purpose of the foregoing disclosure, the self-heating biosensor based on lossy modal resonance proposed in the present invention includes: an optical waveguide unit and a lossy modal resonance layer, wherein the optical waveguide unit is a flat plate including two Plane and at least two sets of opposite sides, optical waveguide One set of two opposite sides of the unit is an optical input end and an optical output end, respectively; the loss mode resonant layer is disposed on one of the planes of the optical waveguide unit, and the loss mode resonant layer is opposite to the optical waveguide unit A heating electrode is formed in one set of two opposite sides, and a biological material sensing area with a biological probe is formed between the two heating electrodes; wherein, the biological material sensing area resonates by the loss mode The layer is formed by a surface modification.

Another object of the present invention is to provide a self-heating biosensing system based on loss modal resonance, including: a broadband light source, an input fiber, a sensing module, an output fiber, and a spectrometer, wherein the input fiber Coupled to the broadband light source; the sensing module is coupled to the input fiber, and the sensing module includes: an optical waveguide unit and a lossy modal resonance layer, wherein the optical waveguide unit is a flat plate, including two planes and at least two groups Two opposite sides of the optical waveguide unit, one of the two opposite sides of the optical waveguide unit is an optical input end and an optical output end respectively; the loss mode resonance layer is disposed on one of the planes of the optical waveguide unit, and the loss mode The state resonance layer respectively forms a heating electrode in one of the two opposite sides of the optical waveguide unit, and a biological material sensing area with a biological probe is formed between the two heating electrodes; the output fiber is coupled to the light The output end; the spectrometer is coupled to the output fiber; wherein, an incident light emitted by the broadband light source undergoes loss modal resonance in the sensing module; the biological material sensing area is formed by performing a surface modification on the loss modal resonance layer .

Another object of the present invention is to provide a method for using a self-heating biosensor based on loss modal resonance, which includes the following steps: placing a test object on an indium tin oxide layer as a loss modal resonance layer A biological material sensing area with a biological probe; an incident light emitted by a broadband light source is input to a glass substrate arranged under the indium tin oxide layer as an optical waveguide unit; the output from the glass substrate is measured by a spectrometer的光; and energize the indium tin oxide layer to heat the biological material sensing area.

When using the aforementioned self-heating biosensor based on lossy modal resonance, since the biomaterial sensing area is formed by surface modification of the lossy modal resonance layer, a biological sensor is formed between the two heating electrodes. The biomaterial sensing area of the needle, when the bioprobe is composed of boride functional groups, the biomaterial sensing area can detect glycosylated hemoglobin (HbA1c); in addition, the self-heating biosensor is disclosed above It is formed by disposing the loss mode resonant layer on the optical waveguide unit, which is quite suitable for the needs of miniaturization. The optical waveguide unit can choose a glass substrate with a lower cost and a smaller volume than the optical waveguide unit, and the loss mode resonant layer can be used. Use light-permeable metal oxide (such as ITO) as the resonance layer of loss mode resonance (LMR), and choose to use mature process and high-yield coating technology (such as radio frequency magnetron sputtering) for production, loss mode The heating electrodes formed on both sides of the biological material sensing area of the resonant layer can further heat the biological material sensing area by applying an external voltage source, so that the operation of measuring the object to be measured is more convenient. For this reason, the self-heating biosensor based on loss modal resonance of the present invention can achieve the purpose of low cost, miniaturization and easy operation.

In addition, compared with surface plasmon resonance (SPR), loss modal resonance (LMR) has the following characteristics: both TE waves and TM waves can resonate with the loss modal resonance layer, while the use of SPR technology can only Resonates with the TM wave.

In order to further understand the technology, means and effects of the present invention to achieve the intended purpose, please refer to the following detailed description and drawings of the present invention. I believe that the features and characteristics of the present invention can be obtained from this in-depth and specific understanding. However, the accompanying drawings are only provided for reference and illustration, and are not intended to limit the present invention.

1. 1’: Self-heating biosensor

10: Optical waveguide unit

11: Optical input

12: Optical output

20: Loss modal resonance layer

21: Heating electrode

22: Biological material sensing area

30: substrate

40: Halogen light source

50: Input fiber

60: output fiber

70: Spectrometer

80: analysis host

90: fiber attenuator

100: DUT

200: External voltage source

300: Fixture

301: Slide

Fig. 1 is a schematic structural diagram of an embodiment of a self-heating biosensor based on loss modal resonance of the present invention; Fig. 2 is a self-heating biosensor of the present invention based on loss modal resonance for measuring an object under test Figure 3 is a schematic structural view of another embodiment of a self-heating biosensor based on lossy modal resonance of the present invention; Figure 4 is a schematic view of another embodiment of a self-heating biosensing system based on lossy modal resonance of the present invention Functional block diagram; Figure 5 is a schematic diagram of a fixture for fixing the sensing module in a self-heating biosensing system based on lossy modal resonance of the present invention; and Figures 6 to 8 are self-heating based on lossy modal resonance of the present invention Schematic diagram of surface modification of a type biosensor.

The following is a specific embodiment to illustrate the implementation of the present invention. Those skilled in the art can easily understand the other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied by other different specific examples, and various details in the specification of the present invention can also be modified and changed based on different viewpoints and applications without departing from the spirit of the present invention.

It should be noted that the structure, ratio, size, number of components, etc. shown in the drawings in this specification are only used to match the content disclosed in the specification for the understanding and reading of those familiar with this technology, and are not intended to limit the scope of the present invention. The limited conditions for implementation do not have technically substantial significance. Any structural modification, proportional relationship change, or size adjustment should fall within the scope of the technical content disclosed in the present invention without affecting the effects and objectives that can be achieved by the present invention.

The technical content and detailed description of the present invention are described below in conjunction with the drawings.

Please refer to FIG. 1 and FIG. 2. In which, FIG. 1 is a schematic structural diagram of an embodiment of a self-heating biosensor based on loss modal resonance of the present invention; FIG. 2 is a self-heating biosensor based on loss modal resonance of the present invention A schematic diagram of the operation of the heated biosensor for measuring an object to be tested.

The self-heating biosensor 1 based on lossy modal resonance according to the embodiment of the present invention includes an optical waveguide unit 10 and a lossy modal resonance layer 20.

Wherein, the optical waveguide unit 10 is a quadrilateral flat plate, including two planes and two sets of two opposite sides. One of the two opposite sides of the optical waveguide unit 10 is a light input end 11 and a light output end 12, respectively. . In this embodiment, the optical waveguide unit 10 may be one of a glass substrate, a quartz substrate, a photonic crystal substrate, or a polymer material substrate, or it may be made of other materials with low light loss.

Although the current optical fiber sensor is the mainstream of development, the manufacturing process of the optical fiber sensor requires grinding and coating, which is not easy to manufacture. Take plastic optical fiber (POF) as an example. Although it has better toughness, it is difficult to withstand the organic solution and high temperature in the process. In addition, the wavelength range of the absorption spectrum of POF is between red light and infrared light. Commonly used wavelengths are not easy to judge SPR and LMR phenomena. Take glass optical fiber (GOF) as an example. Although it can withstand the organic solution and high temperature in the process, and the absorption spectrum is ultraviolet light, which is not a commonly used wavelength, it is not easy to grind and break easily. In summary, this application proposes to use a glass-made planar waveguide as a sensor, and the glass substrate is first coated with a film and then cut into an appropriate size. Glass can resist Compared with the sensor of optical fiber structure, it is easier to fabricate the sensor with the planar waveguide, it is not easy to be damaged, and the yield rate is high.

The lossy modal resonance layer 20 is disposed on one of the planes of the optical waveguide unit 10, and the lossy modal resonance layer 20 respectively forms a heating electrode 21 in the other two opposite sides of the optical waveguide unit 10, In addition, a biological material sensing area 22 with a biological probe is formed between the two heating electrodes 21. The biological material sensing area 22 is formed by performing a surface modification on the lossy mode resonance layer 20. In this embodiment, the biological probe is composed of boride functional groups, and the loss mode resonance layer 20 can be a metal oxide whose dielectric constant is much larger than the real part of the imaginary part, that is, there is a chance to generate a loss mode. The loss mode resonance layer 20 may be made of metal oxide (indium tin oxide (ITO), zinc oxide (ZnO), or titanium oxide (TiO ₂ )) or a polymer material. The biological material sensing area 22 is used to set a device under test (DUT). In this embodiment, the test object 100 may be a phosphate buffer solution (PBS) including glycosylated hemoglobin (HbA1c), as shown in FIG. 2. When the object to be measured 100 is measured, an external voltage source 200 can be applied to the two heating electrodes 21 to heat the biological material sensing area 22. In addition, the depletion modal resonance layer 20 can also form a DNA probe after surface modification, which can be combined with complementary DNA. The DNA probe can release the complementary DNA by heating the biological material sensing region 22.

The principle of LMR and SPR is similar. When incident light enters the lossy modal resonance layer 20 at a critical angle and total reflection (TIR) occurs, the incident light will fade away on the surface of the lossy modal resonance layer 20. Evanescent wave. When the evanescent wave matches the effective refractive index of the loss-mode resonance layer 20, the coupling of the two can observe the light intensity loss of some wavelengths from the spectrum of the reflected light. The wavelength of the light intensity loss is called the LMR wavelength. And it is the focus of observation when the present invention is in use. In addition, both TE wave and TM wave can resonate with the loss mode The layer 20 generates resonance, so there is no need to polarize or filter the incident light, with high sensitivity and convenient use.

In this embodiment, the indium tin oxide layer as the loss mode resonant layer 20 is disposed on the glass substrate as the optical waveguide unit 10 through RF sputter, and the RF sputter is generally used in the field. The technology that is well-known and mature to the knowledgeable will not be described in detail here. The surface modification is performed in the following order: removing surface contaminants of the indium tin oxide layer, hydroxylating the indium tin oxide layer, silanizing the indium tin oxide layer, and decarboxylating the indium tin oxide layer Reaction treatment. The details are as follows.

Please refer to FIG. 3, which is a schematic structural diagram of another embodiment of a self-heating biosensor based on loss modal resonance of the present invention. The self-heating biosensor 1'is substantially the same as the self-heating biosensor 1 of the first embodiment of the present invention, except that the optical waveguide unit 10 is opposite to the other plane provided with the lossy modal resonance layer 20 Disposing on a substrate 30 can reduce the optical waveguide unit 10, while maintaining its mechanical strength, saving cost.

Please refer to Figures 4 and 5, where Figure 4 is a functional block diagram of the self-heating biosensing system based on lossy modal resonance of the present invention; Figure 5 is a functional block diagram of the self-heating biological sensing system based on lossy modal resonance of the present invention Schematic diagram of the fixture for fixing the sensing module in the sensing system.

As shown in FIG. 4, when the aforementioned self-heating biosensor 1 based on loss modal resonance is installed in a system for measurement, the self-heating biosensor 1 as a sensing module is coupled through The input fiber 50 is coupled to a broadband light source (halogen light source 40 as shown in the figure), and the self-heating biosensor 1 is coupled to the spectrometer 70 by coupling the output fiber 60, and finally the spectrometer 70 can be connected to the analysis host 80 to analyze the measured values. Wherein, a fiber attenuator 90 can be added to the input fiber 50, and the light intensity attenuation can be manually adjusted. In this embodiment, the halogen light source 40 used can generate incident light with a wavelength range of 400 nm to 1800 nm; the wavelength range that can be detected by the spectrometer 70 is adapted to the wavelength range of the halogen light source 40. 2 and 4, when the self-heating biosensor 1 is used in the system, the object to be tested 100 is first placed in the biomaterial sensing area 22, and the incident light emitted by the halogen light source 40 The transmitted light input terminal 11 is input to the glass substrate as the optical waveguide unit 10, and the light output from the light output terminal 12 of the glass substrate (that is, the reflected light reflected from the loss mode resonance layer 20) is measured by the spectrometer 70; An external voltage source 200 is applied to the two heating electrodes 21 of the indium tin oxide layer to heat the biological material sensing area 22, so that the DNA probe can release the complementary DNA. The heating electrode 21 can also perform heating and temperature control according to the temperature requirements of different samples during measurement.

As shown in FIG. 5, during the measurement process, a jig 300 can be arranged between the input optical fiber 50 and the output optical fiber 60, and the jig 300 can be used to fix the self-heating biosensor 1 to form a measurement. Test platform. In this embodiment, the jig 300 can be made of stainless steel and matched with an adjustable sliding rail 301 to match the self-heating biosensor 1 of different sizes, so that the measurement application is flexible. The measurement platform of this embodiment is applied to the input fiber 50 and output fiber 60 of the fiber connector (FC). When the thickness of the glass substrate is 0.7mm, the center of the fiber on both sides corresponds to the position of 0.35mm on the glass (in the glass The center of the substrate) can effectively collect incident light, even if the thickness of the glass substrate is thickened, it can still be incident into the glass substrate.

Please refer to FIG. 6 to FIG. 8, which are schematic diagrams of the surface modification of the self-heating biosensor based on loss modal resonance of the present invention.

The indium tin oxide layer on the glass substrate cannot absorb HbA1c by itself, and indium tin oxide (ITO) must be bonded to the boride functional group through the surface modification, so that the boride functional group can absorb With HbA1c, the LMR wavelength will also shift when the indium tin oxide layer is adsorbed to HbA1c, thereby achieving the purpose of detection. The first step is cleaning. The indium tin oxide layer as the loss mode resonance layer 20 is washed sequentially with acetone, absolute ethanol, ultrapure water, potassium hydroxide aqueous solution, and ultrapure water. The second step is hydroxylation treatment. The loss mode resonance layer 20 is cleaned with RCA solution (ie, a mixed solution of ammonia and hydrogen peroxide) to remove organic pollutants and generate hydroxyl groups (OH), as shown in FIG. 6. The third step is the silylation treatment, connecting the hydroxyl group with silane, leaving the terminal isocyanate and boric acid to be combined, as shown in Figure 7. The fourth step is the decarboxylation reaction treatment to remove the carboxyl group (COOH) to facilitate the bonding of the isocyanate group to the benzene ring. As shown in Figure 8, carbon dioxide is generated during the reaction, so bubbles can be observed, which represents the The surface modification has been successful.

In the research process of the present invention, LabView and Mathscript are used to simulate the TE wave and TM wave loss caused by LMR. There are four parameters in the program for users to adjust, including: glass substrate thickness (d ₁ ), ITO thickness (d ₂ ) , The length of the sensing area (L) and the refractive index of the object to be measured (n ₃ ), two parameters change with the wavelength of the incident light, including: the refractive index of the glass substrate (n ₁ ) and the refractive index of the ITO (n ₂ ) . The most obvious parameter that affects the sensitivity of LMR is the thickness of ITO (d ₂ ), which is also one of the characteristics of LMR. SPR cannot improve the sensitivity of the sensor through the thickness of the resonance layer. According to the simulation results, in the case of L=30mm and d ₁ =30mm, the thinner the ITO thickness causes the greater the loss of the LMR wavelength, which is conducive to signal acquisition, the better the sensitivity, and the penetration rate is about -10dB~-20dB. The intensity of the incident light differs from the intensity of the reflected light by 10 to 100 times. Please refer to the following table:

When using the aforementioned self-heating biosensor 1 based on lossy modal resonance, the biological material sensing area 22 is formed by surface modification of the lossy modal resonance layer 20, so that there is a gap between the two heating electrodes 21 A biomaterial sensing region 22 with a boride functional group is formed, which can detect HbA1c. In addition, the aforementioned self-heating biosensor is formed by disposing the loss-mode resonance layer 20 on the optical waveguide unit 10, which is quite suitable for the needs of miniaturization, and the optical waveguide unit 10 can be selected for a lower level than the optical waveguide unit 10. Cost and small glass substrate, and the loss mode resonance layer 20 can be made of light-permeable metal oxide (such as ITO) as the loss mode resonance (LMR) resonance layer, which can be selected with a mature process and high yield Coating technology (such as radio frequency magnetron sputtering) for production. The heating electrodes 21 formed on both sides of the biomaterial sensing area 22 of the loss modal resonance layer 20 can further heat the biomaterial sensing area 22 by applying an external voltage source 200, so that the operation of the object 100 is measured. It is more convenient. For this reason, the self-heating biosensor 1 based on loss modal resonance of the present invention can achieve the purpose of low cost, miniaturization and easy operation.

In addition, loss modal resonance (LMR) has the following characteristics compared to surface plasmon resonance (SPR): both TE waves and TM waves can resonate with loss modal resonance layer 20, while using SPR technology only It can resonate with TM wave.

The above are only detailed descriptions and drawings of the preferred embodiments of the present invention. However, the features of the present invention are not limited to these, and are not intended to limit the present invention. The full scope of the present invention should be covered by the following patent application scope As the standard, all embodiments that conform to the spirit of the patent application of the present invention and similar changes should be included in the scope of the present invention. Anyone familiar with the art in the field of the present invention can easily think of changes or Modifications can be covered in the following patent scope of this case.

1: Self-heating biosensor

10: Optical waveguide unit

11: Optical input

12: Optical output

20: Loss modal resonance layer

21: Heating electrode

22: Biological material sensing area

Claims (7)

A self-heating biosensor based on loss modal resonance, comprising: an optical waveguide unit in the form of a flat plate, including two planes and at least two sets of two opposite sides, one of which is opposite to each other The two sides are respectively an optical input end and an optical output end; and a lossy mode resonant layer disposed on one of the planes of the optical waveguide unit, and the lossy mode resonant layer is positioned relative to the optical waveguide unit A heating electrode is formed in a set of two opposite sides, and a biological material sensing area with a biological probe is formed between the two heating electrodes; wherein, the biological material sensing area is formed by the loss mode The state resonant layer is formed by surface modification; wherein, the biological probe is a boride functional group, and the surface modification includes: the first step is cleaning, and the loss mode resonant layer is formed by using acetone, anhydrous ethanol, Ultrapure water, potassium hydroxide aqueous solution, ultrapure water are cleaned; the second step is hydroxylation treatment, the lossy mode resonance layer is cleaned with RCA solution to remove organic pollutants and generate hydroxyl (OH); third step For silylation treatment, connect the hydroxyl group to silane, leaving the terminal isocyanate and boric acid to be combined; the fourth step is decarboxylation treatment to remove the carboxyl group (COOH) to facilitate the bonding of the isocyanate group to the benzene ring; After the first step to the fourth step, the lossy mode resonance layer generates carbon dioxide to complete the surface modification. The self-heating biosensor based on loss modal resonance as described in the first item of the scope of patent application, wherein the other plane of the optical waveguide unit is disposed on a substrate. The self-heating biosensor based on loss modal resonance described in the first item of the scope of patent application, wherein the loss modal resonance layer is composed of metal oxide or polymer material. The self-heating biosensor based on loss mode resonance described in the first item of the scope of patent application, wherein the optical waveguide unit is one of a glass substrate, a quartz substrate, a photonic crystal substrate, or a polymer material substrate. A self-heating biosensing system based on loss modal resonance, comprising: a broadband light source; an input fiber coupled to the broadband light source; a sensing module coupled to the input fiber, and the sensing module includes : An optical waveguide unit is in the form of a flat plate, including two planes and at least two sets of two opposite sides. One of the two opposite sides of the optical waveguide unit is an optical input end and an optical output end; , The optical input end is coupled to the input fiber; and a lossy modal resonance layer is disposed on one of the planes of the optical waveguide unit, and the lossy modal resonance layer is opposite to one of the sets of the optical waveguide unit A heating electrode is respectively formed in the two sides of the two heating electrodes, and a biological material sensing area with a biological probe is formed between the two heating electrodes; an output fiber is coupled to the light output end; and a spectrometer is coupled to the Output fiber; wherein, an incident light emitted by the broadband light source undergoes loss modal resonance in the sensing module; the biological material sensing area is formed by performing a surface modification on the loss modal resonance layer; Wherein, the biological probe is a boride functional group, and the surface modification includes: the first step is cleaning, and the loss mode resonance layer is sequentially used with acetone, absolute ethanol, ultrapure water, potassium hydroxide aqueous solution, ultrapure Wash with water; the second step is hydroxylation treatment, the lossy mode resonance layer is cleaned with RCA solution to remove organic pollutants and generate hydroxyl groups (OH); the third step is silylation treatment, the hydroxyl groups are connected with silane , Leaving the terminal isocyanate and boric acid combined; the fourth step is a decarboxylation reaction treatment to remove the carboxyl group (COOH) to facilitate the bonding of the isocyanate group to the benzene ring; if after the first step to the fourth step, the loss The modal resonance layer generates carbon dioxide to complete the surface modification. The self-heating biosensing system based on loss modal resonance as described in item 5 of the scope of patent application further includes an optical fiber attenuator and an analysis host coupled to each other, wherein the optical fiber attenuator is coupled to the input optical fiber, The analysis host is coupled to the spectrometer. A method for using a self-heating biosensor based on lossy modal resonance includes the following steps: placing a test object on a lossy modal resonance layer in a biological material sensing area with a biological probe; An incident light emitted by the light source is input to an optical waveguide unit disposed under the lossy modal resonance layer; the light output from the optical waveguide unit is measured by a spectrometer; and the lossy modal resonance layer is energized to the The biological material sensing area is heated; wherein the biological probe is a boride functional group, and the surface modification includes: the first step is cleaning, and the loss mode resonance layer is sequentially used with acetone, absolute ethanol, and ultrapure water , Potassium hydroxide aqueous solution, ultrapure water for cleaning; the second step is hydroxylation treatment, the loss of RCA solution The modal resonance layer is cleaned to remove organic pollutants and generate hydroxyl groups (OH); the third step is silylation treatment, connecting the hydroxyl groups with silane, leaving the terminal isocyanate and boric acid combined; the fourth step is decarboxylation treatment, The removal of the carboxyl group (COOH) facilitates the bonding of the isocyanate group to the benzene ring; after the first step to the fourth step, the lossy mode resonance layer generates carbon dioxide to complete the surface modification.

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