CN107991233B - Extinction spectrum measuring device for noble metal nano array and sensing detection method thereof - Google Patents

Abstract

The invention discloses a noble metal nano-array extinction spectrum measurement device and a sensing and detection method thereof. The device comprises a white light source, a beam lifter, a microscopic component, a sample holder, an optical signal collector, a spectrometer and a computer terminal. The beam is incident on the microscope assembly after changing the propagation path through the beam lifter. The focused beam emitted by the microscope assembly is incident on the sample to be tested. The optical signal collector receives the focused beam transmitted by the sample to be tested and transmits it to the spectrometer. The spectrometer outputs The spectral signal is sent to the computer terminal, and the computer terminal calculates and obtains the concentration of the organic solution according to the change of the extinction peak position of the extinction spectrum of the tested sample relative to the extinction spectrum of the noble metal nanoarray. The extinction spectrum of the noble metal nanoarray realizes precise positioning measurement; the process of realizing the concentration detection of organic solution by using the device is simple, the cost is low, and the sensitivity is high.

Description

Precious metal nanoarray extinction spectrum measurement device and sensing detection method thereof

technical field

The invention relates to a sensing detection technology of organic solution concentration, in particular to a noble metal nano-array extinction spectrum measurement device and a method for realizing organic solution concentration sensing detection by using the same.

Background technique

It is well known that the extinction properties of noble metal nanoparticles are strongly dependent on their size, morphology, and environmental media. The extinction characteristics of noble metal nanoparticles can be characterized and analyzed by the measurement of extinction spectrum of noble metal nanoparticles. Generally, the extinction spectrum of noble metal nanoparticles is obtained by measuring the absorption spectrum of the colloidal solution of noble metal nanoparticles. Extinction spectroscopy requires simultaneous measurement of the scattering and absorption spectra of noble metal nanoarrays. At present, the scattering spectrum of noble metal nanoarrays needs to be measured with an integrating sphere, and the absorption spectrum of noble metal nanoarrays needs to be measured with an ultraviolet-visible-near-infrared spectrophotometer. The measurement method using integrating spheres requires multi-step luminous flux and spectral determination. The measurement method using the UV-Vis-NIR spectrophotometer requires a series of steps such as self-checking, dark current and baseline calibration. Therefore, these two methods have the shortcomings of long measurement time and cumbersome operation. Infrared spectrophotometers can only measure the overall spectral characteristics of the sample, that is, they cannot perform local precise localization measurement of the sample, so they are not suitable for the measurement of extinction spectra of noble metal nanoarray samples with complex structures.

On the other hand, as far as the sensing and detection of organic solution concentration is concerned, there are many commonly used methods, such as: absorption spectroscopy method based on Lambert-Beer law, gas/liquid chromatography method based on the principle of substance separation and adsorption, molecular ionization based method Molecular mass spectrometry, Raman spectroscopy based on inelastic scattering of light and matter, etc. Although these common methods can effectively realize the sensing and detection of the concentration of organic solutions, they also have their own shortcomings. Gas/liquid chromatography based on the principle of substance separation and adsorption and molecular mass spectrometry based on molecular ionization technology have high detection costs; Raman spectroscopy based on inelastic scattering of light and matter is easily affected by fluorescence and optical system parameters. Not ideal.

Therefore, a device that can accurately measure the extinction spectrum of the measured sample of noble metal nanoarrays with micron-scale size and complex structure is designed, and the extinction spectrum of noble metal nanoarrays is strongly affected by its own size, morphology and environmental medium. It has important application value to carry out accurate sensing detection of organic solution concentration.

SUMMARY OF THE INVENTION

The first technical problem to be solved by the present invention is to provide a noble metal nano-array extinction spectrum measurement device with a simple structure and convenient operation, which can accurately locate the measured sample of the noble metal nano-array with a micron size and a complex structure. Measurement.

The second technical problem to be solved by the present invention is to provide a method for realizing organic solution concentration sensing detection by using a noble metal nanoarray extinction spectrum measuring device, which has simple detection process, low detection cost and high detection sensitivity.

The technical solution adopted by the present invention to solve the above-mentioned first technical problem is: a noble metal nano-array extinction spectrum measuring device, which is characterized in that it includes a white light source, a beam lifter for changing the propagation path of the beam, a microscope assembly, a In the sample holder, optical signal collector, spectrometer and computer terminal that clamp the sample to be tested and place the sample horizontally, the beam emitted by the white light source is incident on the beam lifter after changing the propagation path. On the microscope assembly, the focused beam emitted by the microscope assembly is incident on the sample to be tested, and the optical signal collector receives the focused beam transmitted through the sample to be tested, and transmits the focused beam To the spectrometer, the spectrometer outputs a spectral signal to the computer terminal.

The beam lifter is composed of a vertically arranged first bracket, a first mirror arranged at the lower part of the first bracket, and a second reflection mirror arranged at the upper part of the first bracket. The light beam emitted by the white light source is incident on the first reflecting mirror, the light beam reflected by the first reflecting mirror is incident on the second reflecting mirror, and the light beam reflected by the second reflecting mirror is incident on the on the described microscope assembly. Here, the function of the beam lifter is to lift the light beam from a low position to a high position, which can be achieved by using two mirrors. The beam lifter has a simple structure, low cost and convenient operation.

Both the first reflecting mirror and the second reflecting mirror are at an angle of 45 degrees with the horizontal plane, the first reflecting mirror and the second reflecting mirror are arranged in parallel, and the reflection of the first reflecting mirror The surface is directly opposite to the reflecting surface of the second reflecting mirror. Here, the installation positions of the first reflector and the second reflector are limited to ensure that all light beams reflected by the first reflector are received by the second reflector, and all light beams reflected by the second reflector are received by the microscope assembly.

The microscopic assembly consists of a vertically arranged second bracket, a semi-transparent mirror and an objective lens sequentially connected to the second bracket from top to bottom, connected to the second bracket and located on the second bracket. The light absorbing plate on the propagation path of the light beam transmitted by the half mirror is composed of the light absorbing plate, the half mirror and the objective lens are located directly above the sample holder, and the beam lifter exits the light absorbing plate. The light beam is incident on the half mirror, the beam reflected by the half mirror is incident on the objective lens, and the focused beam emitted by the objective lens is incident on the tested sample, The light beam transmitted by the half mirror is incident on the light absorption plate, and the light absorption plate absorbs the light beam transmitted by the half mirror. Here, first use the half mirror to change the propagation path of the light beam reflected from the second mirror, so that the light beam reflected by the half mirror is vertically incident on the objective lens, and the light beam transmitted by the half mirror is incident on the objective lens. The light absorbing plate is absorbed by the light absorbing plate; and then the light beam reflected by the half mirror is focused by the objective lens.

The half-mirror and the horizontal plane are at an angle of 45 degrees, the reflection surface of the half-mirror is opposite to the reflection surface of the second reflection mirror; the light-absorbing plate is vertically arranged with the The transflective mirror is at a 45-degree angle. Here, by limiting the relative position of the second mirror and the half mirror, it can be ensured that all the light beams reflected by the second mirror are received by the half mirror; by limiting the relative position of the half mirror and the light absorbing plate , which can ensure that all the light beam transmitted by the half mirror is absorbed by the light absorbing plate.

The second bracket is also connected with a CCD (Charge-coupled Device, charge-coupled device) camera, the CCD camera is located directly above the half mirror, and the output end of the CCD camera is connected to the The computer terminal is connected, and the CCD camera acquires the morphology of the noble metal nanoarray in the tested sample observed through the objective lens. Here, a CCD camera is set directly above the objective lens, and the CCD camera is used to obtain the topography of the noble metal nanoarray as the sample to be tested, which expands the function of the device.

The noble metal nano-array extinction spectrum measurement device further includes a first three-dimensional position adjusting device for adjusting the position of the sample holder, and the first three-dimensional position adjusting device consists of a first positioning plate, mounted on the first The first three-dimensional displacement platform on the positioning plate and the first connecting rod connecting the first three-dimensional displacement platform and the sample holder are composed, and the position of the sample holder is adjusted through the first three-dimensional displacement platform so that the The sample to be tested is located just below the objective lens. Here, the first three-dimensional displacement platform is used to adjust the position of the sample holder, so that the sample to be tested is located directly under the objective lens, so that the focused beam emitted by the objective lens is completely incident on the sample to be tested.

The optical signal collector is composed of an optical fiber probe clamp and an optical fiber probe clamped by the optical fiber probe clamp. The optical fiber probe is placed vertically and its receiving end is located directly under the tested sample, so the optical fiber probe is placed vertically. The optical fiber probe receives the focused beam transmitted through the sample to be tested, the output end of the optical fiber probe is connected with the input end of the spectrometer through a conducting fiber, and the optical fiber probe transmits and transmits through the The focused beam of the test sample is given to the spectrometer;

The noble metal nano-array extinction spectrum measurement device also includes a second three-dimensional position adjustment device for adjusting the position of the optical signal collector, and the second three-dimensional position adjustment device consists of a second positioning plate, mounted on the The second three-dimensional displacement platform on the second positioning plate is composed of a second connecting rod connecting the second three-dimensional displacement platform and the optical fiber probe fixture, and the optical fiber probe is adjusted through the second three-dimensional displacement platform The position of the fixture is such that the optical fiber probe is located directly below the sample to be tested and close to the lower surface of the sample to be tested. Here, the second three-dimensional displacement platform is used to adjust the position of the fiber optic probe fixture, so that the fiber optic probe is located directly below the sample to be tested and close to the lower surface of the sample to be tested, so that the information collected by the fiber optic probe is more accurate.

The noble metal nanoarray extinction spectrum measurement device further includes a base, the white light source and the spectrometer are placed on the base, and the bottom of the first support and the bottom of the second support are respectively connected to the base. The base is fixedly connected, and the first positioning plate and the second positioning plate are respectively fixedly connected to the base. Here, the base is used to bring all the parts together to form a whole.

The technical solution adopted by the present invention to solve the above-mentioned second technical problem is: a sensing and detection method of the above-mentioned noble metal nano-array extinction spectrum measuring device, characterized in that: the noble metal nano-array extinction spectrum measuring device is used to measure the concentration of the organic solution. Sensing detection, including the following steps:

①Using electron beam etching technology to prepare a precious metal nanoarray with a specific pattern on the conductive glass deposited with a conductive film; then use the conductive glass with a specific pattern of precious metal nanoarrays as the sample to be tested;

②Turn on the white light source; then adjust the position of the optical fiber probe fixture through the second three-dimensional displacement platform, so that the receiving port of the optical fiber probe is located in the focal plane of the objective lens, so that the optical fiber can be clearly displayed on the monitor of the computer terminal through the objective lens and the CCD camera The receiving port of the probe; turn on the spectrometer again, and set the signal acquisition parameters; at this time, when the white light source is turned on, the spectral signal output by the spectrometer is the spectrum of the white light source, denoted as I(λ), and transmitted to the computer terminal, by the computer The terminal is saved; among them, λ represents the wavelength;

③Adjust the position of the fiber optic probe fixture through the second three-dimensional displacement platform, so that the fiber optic probe moves vertically downward. The purpose of moving the fiber optic probe downward is to make the sample under test display on the focal plane. Because the conductive glass is very thin, the fiber optic probe is generally moved downward. Then use the sample holder to hold the sample to be tested and place the sample horizontally; then adjust the position of the sample holder through the first three-dimensional displacement platform, so that the noble metal nanoarray in the sample to be tested is located in the focal plane of the objective lens , and ensure that the noble metal nanoarray image in the tested sample is clearly displayed on the monitor of the computer terminal through the objective lens and CCD camera; and then adjust the position of the fiber probe clamp through the second three-dimensional displacement platform, so that the fiber probe is located in the tested sample. and make the receiving port of the fiber probe as close as possible to the lower surface of the sample under test; at this time, the spectral signal output by the spectrometer when the white light source is turned on is the transmission spectrum of the noble metal nanoarray in the sample under test, denoted as T ₁ (λ), and transmitted to the computer terminal, and saved by the computer terminal;

4. Turn off the white light source; take the spectral signal output by the spectrometer when the white light source is turned off at this time as the first background spectrum, denoted as B ₁ (λ), and transmit it to the computer terminal for storage by the computer terminal;

⑤ According to the definition _of extinction spectrum, the computer terminal calculates the _extinction spectrum E _{1 (} λ);

⑥ Take the organic solution to be tested and add it dropwise to the noble metal nanoarray in the sample to be tested; then take the spectral signal output by the spectrometer when the white light source is turned off at this time as the second background spectrum, denoted as B ₂ (λ), and transmitted to the computer terminal, and saved by the computer terminal;

⑦Turn on the white light source; at this time, when the white light source is turned on, the spectral signal output by the spectrometer is the transmission spectrum of the precious metal nanoarray with the organic solution to be tested dropwise added, denoted as T ₂ (λ), and transmitted to the computer terminal, by the computer terminal save;

⑧According to the definition of extinction spectrum, the computer terminal uses the formula E ₂ (λ)=I(λ)-T ₂ (λ)+B ₂ (λ) to calculate and obtain the extinction spectrum of the noble metal nano-array with the organic solution to be tested dropwise added E ₂ (λ);

⑨ Taking E ₁ (λ) as the reference spectrum, and then according to the change of the position or intensity of the extinction peak in E ₂ (λ) relative to the extinction peak in E ₁ (λ), the concentration of the organic solution to be tested is obtained.

Compared with the prior art, the advantages of the present invention are:

1) The device of the present invention adopts few mechanical parts and optical elements, which makes the structure of the device simpler and easier to realize.

2) The device of the present invention only needs to turn on and off the white light source and the spectrometer to realize the measurement, the operation is simple, and the measurement time is short.

3) The device of the present invention directly uses the optical signal collector to receive the focused beam transmitted through the sample to be tested to obtain the extinction spectrum of the noble metal nanoarray, and the detection process is fast and convenient.

4) The device of the present invention uses the objective lens to focus the light beam on the surface of the sample to be measured and uses the CCD camera to image clearly, so it can achieve precise positioning and measurement of the extinction spectra of various noble metal nanoarray structures at the micron scale.

5) After using the device of the present invention to realize the sensing detection of the concentration of the organic solution, the used noble metal nano-array can be reused for many times after cleaning, which reduces the detection cost.

6) The method for realizing the organic solution concentration sensing detection by utilizing the noble metal nano-array extinction spectrum measuring device has the advantages of simple process, low detection cost and high detection sensitivity.

Description of drawings

Fig. 1 is the composition structure schematic diagram of the noble metal nanoarray extinction spectrum measuring device of the present invention;

2 is a schematic diagram of the composition and structure of a first three-dimensional position adjustment device in the noble metal nanoarray extinction spectrum measurement device of the present invention;

3 is a schematic diagram of the composition and structure of the second three-dimensional position adjustment device in the noble metal nanoarray extinction spectrum measurement device of the present invention;

4 is a scanning electron microscope photograph of a gold nanoarray with a periodic structure, wherein the diameter of the gold nanoparticles is 200 nanometers, the height is 75 nanometers, and the spacing between the gold nanoparticles is 50 nanometers;

Figure 5 shows the droplets obtained after dropping 20 microliters of 20%, 40%, 60% and 80% ethanol solutions and 99.7% absolute ethanol dropwise onto the gold nanoarrays in Example 3, respectively. Extinction spectra of gold nanoarrays added with 20%, 40%, 60% and 80% ethanol solutions and 99.7% absolute ethanol;

Fig. 6 is the concentration response curve diagram of different concentrations of ethanol solution and absolute ethanol in embodiment three;

Figure 7 shows the droplets obtained after dripping 20 microliters of enrofloxacin solutions with concentrations of 5 mg/L, 10 mg/L, 15 mg/L, 20 mg/L and 25 mg/L on the gold nanoarray in Example 4. Extinction spectra of gold nanoarrays added with enrofloxacin solutions at concentrations of 5 mg/L, 10 mg/L, 15 mg/L, 20 mg/L and 25 mg/L;

Fig. 8 is the concentration response curve diagram of the enrofloxacin solution of different concentrations in embodiment four;

FIG. 9 is a scanning electron microscope photograph of a gold nanoarray with a periodic structure, wherein the diameter of the gold nanoparticles is 200 nanometers, the height is 75 nanometers, and the distance between the gold nanoparticles is 100 nanometers;

Figure 10 shows the droplets obtained after dropping 20 microliters of 20%, 40%, 60%, and 80% ethanol solutions and 99.7% absolute ethanol dropwise onto the gold nanoarrays in Example 5, respectively. Extinction spectra of gold nanoarrays added with 20%, 40%, 60% and 80% ethanol solutions and 99.7% absolute ethanol;

Fig. 11 is the concentration response curve diagram of different concentrations of ethanol solution and absolute ethanol in Example 5;

Figure 12 shows the droplets obtained after dripping 20 microliters of enrofloxacin solutions with concentrations of 5 mg/L, 10 mg/L, 15 mg/L, 20 mg/L and 25 mg/L on the gold nanoarray in Example 6. Extinction spectra of gold nanoarrays added with enrofloxacin solutions at concentrations of 5 mg/L, 10 mg/L, 15 mg/L, 20 mg/L and 25 mg/L;

Fig. 13 is the concentration response curve diagram of different concentrations of enrofloxacin solution in Example 6.

Detailed ways

The present invention will be further described in detail below with reference to the embodiments of the accompanying drawings.

Example 1:

A noble metal nanoarray extinction spectrum measurement device proposed in this embodiment, as shown in FIG. 1 , includes a white light source 2, a beam lifter 3 for changing the beam propagation path, a microscopic component 4, a The sample holder 5, the optical signal collector 6, the spectrometer 7 and the computer terminal 8 are placed horizontally on the sample to be tested. The light beam emitted by the white light source 2 is incident on the microscope assembly 4 after changing the propagation path through the beam lifter 3, and the display is displayed. The focused beam emitted by the micro-component 4 is incident on the tested sample 9 , and the optical signal collector 6 receives the focused beam transmitted through the tested sample 9 and transmits the focused beam to the spectrometer 7 , and the spectrometer 7 outputs a spectral signal to the computer terminal 8 .

In this specific embodiment, the beam lifter 3 consists of a first bracket 31 arranged vertically, a first mirror 32 arranged at the lower part of the first bracket 31 and a second mirror 33 arranged at the upper part of the first bracket 31 Composition, the light beam emitted by the white light source 2 is incident on the first reflecting mirror 32, the light beam reflected by the first reflecting mirror 32 is incident on the second reflecting mirror 33, and the light beam reflected by the second reflecting mirror 33 is incident on the microscope assembly 4; The function of the beam lifter 3 is to lift the light beam from a low position to a high position, which can be achieved by using two mirrors. The light lifter has a simple structure, low cost and convenient operation.

In this specific embodiment, both the first reflecting mirror 32 and the second reflecting mirror 33 are at an angle of 45 degrees with the horizontal plane, the first reflecting mirror 32 and the second reflecting mirror 33 are arranged in parallel, and the reflecting surface of the first reflecting mirror 32 is parallel to the first reflecting mirror 32 and the second reflecting mirror 33. The reflecting surfaces of the two reflecting mirrors 33 are facing each other; the installation positions of the first reflecting mirror 32 and the second reflecting mirror 33 are limited to ensure that all the light beams reflected by the first reflecting mirror 32 are received by the second reflecting mirror 33 and the second reflecting mirror 33 All the light beams reflected by the mirror 33 are received by the microscope assembly 4 .

In this specific embodiment, the microscope assembly 4 is composed of a vertically arranged second bracket 41 , a half mirror 42 and an objective lens 43 sequentially connected to the second bracket 41 from top to bottom, and connected to the second bracket 41 It consists of a light absorbing plate 44 on the upper part and located on the propagation path of the light beam transmitted by the half mirror 42; the half mirror 42 and the objective lens 43 are located directly above the sample holder 5; On the half mirror 42 , the beam reflected by the half mirror 42 is incident on the objective lens 43 , the focused beam emitted by the objective lens 43 is incident on the tested sample 9 , and the beam transmitted by the half mirror 42 is incident on the light absorbing plate 44 , the light absorbing plate 44 absorbs the light beam transmitted by the half mirror 42; first, the half mirror 42 is used to change the propagation path of the light beam reflected from the second mirror 33, so that the light beam reflected by the half mirror 42 is vertically incident to the objective lens 43, and the light beam transmitted by the half mirror 42 is incident on the light absorbing plate 44 and absorbed by the light absorbing plate 44; then the light beam reflected by the half mirror 42 is focused by the objective lens 43. 4 has a simple structure and convenient function realization.

In this specific embodiment, the half mirror 42 is at an angle of 45 degrees to the horizontal plane, and the reflective surface of the half mirror 42 is opposite to the reflective surface of the second mirror 33; The mirror 42 is at an angle of 45 degrees; by limiting the relative position of the second mirror 33 and the half mirror 42, it can be ensured that all the light beams reflected by the second mirror 33 are received by the half mirror 42; The relative position of the half mirror 42 and the light absorbing plate 44 can ensure that all the light beams transmitted by the half mirror 42 are absorbed by the light absorbing plate 44 .

In this specific embodiment, the second bracket 41 is also connected with a CCD (Charge-coupled Device, charge-coupled device) camera 45, the CCD camera 45 is located directly above the half mirror 42, and the output end of the CCD camera 45 is connected to the The computer terminal 8 is connected, and the CCD camera 45 obtains the appearance of the noble metal nanoarray in the tested sample 9 observed through the objective lens 43; by setting a CCD camera 45 directly above the objective lens 43, the CCD camera 45 is used to obtain the measured data. The morphology of the noble metal nanoarrays of sample 9 extends the functionality of the device.

In this specific embodiment, the optical signal collector 6 is shown in FIG. 3 , which is composed of a fiber probe clamp 64 and a fiber probe 65 clamped by the fiber probe clamp 64. The fiber probe 65 is placed vertically and its receiving end is located at the Just below the test sample 9, the fiber probe 65 receives the focused beam transmitted through the test sample 9, the output end of the fiber probe 65 is connected to the input end of the spectrometer 7 through the conducting fiber 66, and the fiber probe 65 transmits the light transmitted through the test sample 9. Focus the beam to the spectrometer 7 .

Embodiment 2:

A noble metal nanoarray extinction spectrum measurement device proposed in this embodiment is a further improvement to the device of the first embodiment, as shown in FIG. 2 and FIG. The position adjusting device, the second three-dimensional position adjusting device and the base 1 for adjusting the position of the optical signal collector 6 and the base 1 (see FIG. 1 ). The first three-dimensional displacement platform 52 and the first connecting rod 53 connecting the first three-dimensional displacement platform 52 and the sample holder 5 are composed of the first micrometer screw 521 and the second micrometer wire in the first three-dimensional displacement platform 52. The rod 522 and the third micrometer screw 523 adjust the position of the sample holder 5 so that the measured sample 9 is located directly under the objective lens 43; The second three-dimensional displacement platform 62 and the second connecting rod 63 connecting the second three-dimensional displacement platform 62 and the optical fiber probe fixture 64 are composed of the first micrometer screw 621 and the second micrometer screw in the second three-dimensional displacement platform 62 . 622 and the third micrometer screw 623 adjust the position of the optical fiber probe clamp 64 so that the optical fiber probe 65 is located directly below the measured sample 9 and is close to the lower surface of the measured sample 9; the white light source 2 and the spectrometer 7 are placed on the base 1, The bottom of the first bracket 31 and the bottom of the second bracket 41 are fixedly connected to the base 1 respectively, and the first positioning plate 51 and the second positioning plate 61 are fixedly connected to the base 1 respectively.

Here, the first three-dimensional displacement platform 52 is used to adjust the position of the sample holder 5, so that the tested sample 9 is located directly below the objective lens 43, so that the focused beam emitted by the objective lens 43 is completely incident on the tested sample 9; Displace the platform 62 to adjust the position of the optical fiber probe fixture 64, so that the optical fiber probe 65 is located directly below the tested sample 9 and close to the lower surface of the tested sample 9, so that the information collected by the optical fiber probe 65 is more accurate; The parts are grouped together to form a whole.

In the above-mentioned first and second embodiments, the white light source 2 adopts the existing xenon light source or bromine tungsten light source or other white light source in the prior art; The spectrometer 7 adopts the existing technology; the computer terminal 8 adopts the existing technology, with a display, and the existing spectrometer control software, the existing image processing software and the existing noble metal nanoarray extinction spectrum are installed in the computer terminal 8 The computer terminal 8 controls the spectrometer 7 to collect signals through the spectrometer 7 control software and processes the spectral signal output by the spectrometer 7, and the computer terminal 8 calculates the extinction spectrum of the noble metal nanoarray through the calculation software of the extinction spectrum of the noble metal nanoarray, The computer terminal 8 processes the precious metal nanoarrays acquired by the CCD camera 45 through image processing software; the first three-dimensional displacement platform 52 and the second three-dimensional displacement platform 62 both use existing three-dimensional displacement platforms, and have three micrometer screw rods; The probe clamp 64 adopts the existing clamping device capable of stably and reliably clamping the object; the optical fiber probe 65 adopts the multi-mode plastic optical fiber or other medium optical fibers in the prior art.

Embodiment three:

This embodiment proposes a method for sensing and detecting the concentration of an ethanol solution by using the noble metal nanoarray extinction spectrum measuring device of the second embodiment, which includes the following steps:

①Using the existing electron beam etching technology, a gold nanoarray with periodic structure is prepared on the conductive glass deposited with the conductive film. The gold nanoparticle is a nano cylinder with a diameter of 200 nanometers and a height of 75 nanometers. The spacing between them is 50 nanometers, and the scanning electron microscope (SEM) picture is shown in Figure 4; then the conductive glass with gold nanoarrays is used as the tested sample.

Here, the conductive glass can be a glass substrate deposited with a conductive film, or a plexiglass substrate deposited with a conductive film, and the conductive film is an ITO (Indium-Tin Oxide, indium tin oxide) film, or FTO (SnO2: F, namely fluorine-doped tin dioxide) thin film; the precious metal material is gold or silver.

②Turn on the white light source; then adjust the position of the optical fiber probe fixture through the second three-dimensional displacement platform, so that the receiving port of the optical fiber probe is located in the focal plane of the objective lens, so that the optical fiber can be clearly displayed on the monitor of the computer terminal through the objective lens and the CCD camera The receiving port of the probe; turn on the spectrometer again, and set the signal acquisition parameters, such as setting the integration time to 1 second; at this time, when the white light source is turned on, the spectral signal output by the spectrometer is the spectrum of the white light source, denoted as I(λ) , and transmitted to the computer terminal, and saved by the computer terminal; among them, λ represents the wavelength.

③Adjust the position of the fiber optic probe fixture through the second three-dimensional displacement platform, so that the fiber optic probe moves vertically downward. The purpose of moving the fiber optic probe downward is to make the sample under test display on the focal plane. Because the conductive glass is very thin, the fiber optic probe is generally moved downward. Then use the sample holder to hold the sample to be tested and place the sample horizontally; then adjust the position of the sample holder through the first three-dimensional displacement platform, so that the gold nanoarray in the sample to be tested is located in the focal plane of the objective lens , and ensure that the gold nanoarray image in the tested sample is clearly displayed on the monitor of the computer terminal through the objective lens and the CCD camera; and then adjust the position of the fiber probe clamp through the second three-dimensional displacement platform, so that the fiber probe is located in the tested sample. and make the receiving port of the fiber probe as close as possible to the lower surface of the sample under test; at this time, the spectral signal output by the spectrometer when the white light source is turned on is the transmission spectrum of the gold nanoarray in the sample under test, denoted as T ₁ (λ), and transmitted to the computer terminal, and saved by the computer terminal.

④ Turn off the white light source; take the spectral signal output by the spectrometer when the white light source is off at this time as the first background spectrum, denoted as B ₁ (λ), and transmit it to the computer terminal and save it by the computer terminal.

⑤ According to the definition of extinction spectrum, the computer terminal uses the formula E ₁ (λ)=I(λ)-T ₁ (λ)+B ₁ (λ) to calculate the extinction spectrum E ₁ ( λ).

⑥ Pipette 20 microliters of ethanol solution as the organic solution to be tested, and add it dropwise to the gold nanoarray in the tested sample; then use the spectral signal output by the spectrometer when the white light source is turned off at this time as the first Two background spectra, denoted as B ₂ (λ), are transmitted to the computer terminal and saved by the computer terminal.

⑦Turn on the white light source; at this time, when the white light source is turned on, the spectral signal output by the spectrometer is the transmission spectrum of the gold nanoarray with the organic solution to be tested dropwise added, denoted as T ₂ (λ), and transmitted to the computer terminal, by the computer Terminal saves.

⑧According to the definition of extinction spectrum, the computer terminal uses the formula E ₂ (λ)=I(λ)-T ₂ (λ)+B ₂ (λ) to calculate and obtain the extinction spectrum of the gold nanoarray with the organic solution to be tested dropwise added E ₂ (λ).

⑨ Taking E ₁ (λ) as the reference spectrum, and then according to the change of the position or intensity of the extinction peak in E ₂ (λ) relative to the extinction peak in E ₁ (λ), the concentration of the organic solution to be tested is obtained.

Figure 5 shows the results obtained after dropping 20 microliters of 20%, 40%, 60% and 80% ethanol solutions and 99.7% absolute ethanol dropwise onto the gold nanoarrays in Example 3, respectively. The extinction spectra of gold nanoarrays with 20%, 40%, 60% and 80% ethanol solutions and 99.7% absolute ethanol added dropwise. Ethanol solutions of different concentrations are prepared by mixing ethanol with a purity greater than 99.99% with deionized water. It can be seen from Figure 5 that with the increase of the concentration of the ethanol solution, the position of the extinction peak of the extinction spectrum shifts red.

Figure 6 shows the concentration response curves of ethanol solutions of different concentrations and absolute ethanol in Example 3. After obtaining the extinction spectrum of the gold nanoarray with the ethanol solution added dropwise, the concentration of the dropwise ethanol solution can be obtained according to FIG. 6 .

Embodiment 4:

This embodiment proposes a method for sensing and detecting the concentration of enrofloxacin solution by utilizing the noble metal nanoarray extinction spectrum measuring device of the second embodiment, which includes the following steps:

①Using the existing electron beam etching technology, a gold nanoarray with periodic structure is prepared on the conductive glass deposited with the conductive film. The gold nanoparticle is a nano cylinder with a diameter of 200 nanometers and a height of 75 nanometers. The spacing between them is 50 nanometers, and the scanning electron microscope (SEM) picture is shown in Figure 4; then the conductive glass with gold nanoarrays is used as the tested sample.

Here, the conductive glass can be a glass substrate deposited with a conductive film, or a plexiglass substrate deposited with a conductive film, and the conductive film is an ITO (Indium-Tin Oxide, indium tin oxide) film, or FTO (SnO2: F, namely fluorine-doped tin dioxide) thin film; the precious metal material is gold or silver.

②Turn on the white light source; then adjust the position of the optical fiber probe fixture through the second three-dimensional displacement platform, so that the receiving port of the optical fiber probe is located in the focal plane of the objective lens, so that the optical fiber can be clearly displayed on the monitor of the computer terminal through the objective lens and the CCD camera The receiving port of the probe; turn on the spectrometer again, and set the signal acquisition parameters, such as setting the integration time to 1 second; at this time, when the white light source is turned on, the spectral signal output by the spectrometer is the spectrum of the white light source, denoted as I(λ) , and transmitted to the computer terminal, and saved by the computer terminal; among them, λ represents the wavelength.

③Adjust the position of the optical fiber probe fixture through the second three-dimensional displacement platform, so that the optical fiber probe moves down vertically. The purpose of moving the optical fiber probe down is to display the tested sample on the focal plane. Because the conductive glass is very thin, it can be used in general. It is enough to move the optical fiber probe down by 2cm; then use the sample holder to hold the sample to be tested and place the sample horizontally; then adjust the position of the sample holder through the first three-dimensional displacement platform, so that the gold nanoarrays in the sample are tested. It is located in the focal plane of the objective lens, and ensures that the gold nanoarray image in the tested sample can be clearly displayed on the monitor of the computer terminal through the objective lens and the CCD camera; then adjust the position of the fiber probe clamp through the second three-dimensional displacement platform, so that the fiber The probe is located directly under the sample to be tested, and the receiving port of the fiber optic probe is as close as possible to the lower surface of the sample to be tested; at this time, the spectral signal output by the spectrometer when the white light source is turned on is the transmission spectrum of the gold nanoarray in the sample to be tested. , denoted as T ₁ (λ), and transmitted to the computer terminal and saved by the computer terminal.

④ Turn off the white light source; take the spectral signal output by the spectrometer when the white light source is off at this time as the first background spectrum, denoted as B ₁ (λ), and transmit it to the computer terminal and save it by the computer terminal.

⑤ According to the definition of extinction spectrum, the computer terminal uses the formula E ₁ (λ)=I(λ)-T ₁ (λ)+B ₁ (λ) to calculate the extinction spectrum E ₁ ( λ).

⑥ Pipette 20 microliters of enrofloxacin solution as the organic solution to be tested, and add it dropwise to the gold nanoarray in the tested sample; The signal is taken as the second background spectrum, denoted as B ₂ (λ), and transmitted to the computer terminal and stored by the computer terminal.

⑦Turn on the white light source; at this time, when the white light source is turned on, the spectral signal output by the spectrometer is the transmission spectrum of the gold nanoarray with the organic solution to be tested dropwise added, denoted as T ₂ (λ), and transmitted to the computer terminal, by the computer Terminal saves.

⑧According to the definition of extinction spectrum, the computer terminal uses the formula E ₂ (λ)=I(λ)-T ₂ (λ)+B ₂ (λ) to calculate and obtain the extinction spectrum of the gold nanoarray with the organic solution to be tested dropwise added E ₂ (λ).

⑨ Taking E ₁ (λ) as the reference spectrum, and then according to the change of the position or intensity of the extinction peak in E ₂ (λ) relative to the extinction peak in E ₁ (λ), the concentration of the organic solution to be tested is obtained.

Figure 7 shows that in Example 4, 20 microliters of enrofloxacin solutions with concentrations of 5 mg/L, 10 mg/L, 15 mg/L, 20 mg/L and 25 mg/L were added dropwise to the gold nanoarray, respectively. The extinction spectra of gold nanoarrays dropwise with enrofloxacin solutions at concentrations of 5 mg/L, 10 mg/L, 15 mg/L, 20 mg/L and 25 mg/L. Enrofloxacin solutions of different concentrations were prepared by formulating enrofloxacin powder with a purity greater than or equal to 98% (HPLC) with analytically pure ethanol solution. It can be seen from Figure 7 that with the increase of the concentration of enrofloxacin solution, the position of the extinction peak in the extinction spectrum is red-shifted and the peak intensity is enhanced.

Figure 8 shows the concentration response curve diagram of different concentrations of enrofloxacin solution in Example 4. After obtaining the extinction spectrum of the gold nanoarray with the enrofloxacin solution added dropwise, the concentration of the dropwise enrofloxacin solution can be obtained according to FIG. 8 .

Embodiment 5:

This embodiment proposes a method for sensing and detecting the concentration of an ethanol solution by using the noble metal nanoarray extinction spectrum measuring device of the second embodiment. The specific steps are the same as the specific steps of the method for implementing the sensing and detection of the concentration of an ethanol solution in the third embodiment. The only difference is that the gold nano-arrays with periodic structure are different. In this embodiment, the gold nanoparticles are nano cylinders with a diameter of 200 nanometers and a height of 75 nanometers, and the distance between the gold nanoparticles is 100 nanometers. nanometer, and its scanning electron microscope (SEM) photo is shown in Figure 9.

Figure 10 shows that in Example 5, 20 microliters of ethanol solutions with a concentration of 20%, 40%, 60% and 80% and anhydrous ethanol with a concentration of 99.7% were added dropwise on the gold nanoarrays, respectively. The extinction spectra of gold nanoarrays with 20%, 40%, 60% and 80% ethanol solutions and 99.7% absolute ethanol added dropwise. Ethanol solutions of different concentrations are prepared by mixing ethanol with a purity greater than 99.99% with deionized water. As can be seen from Figure 10, with the increase of the concentration of the ethanol solution, the position of the extinction peak of the extinction spectrum shifted to red; and it was found that the variation of the position of the extinction peak of the extinction spectrum in Example 5 was much smaller than that of the Example The change in the position of the extinction peak of the extinction spectrum in Example 3 is related to the weakening of the localized surface plasmon resonance (LSPR) caused by the increase in the particle spacing of the gold nanoarray in Example 5.

Figure 11 shows the concentration response curves of ethanol solutions of different concentrations and absolute ethanol in Example 5. After obtaining the extinction spectrum of the gold nanoarray with the ethanol solution added dropwise, the concentration of the dropwise ethanol solution can be obtained according to FIG. 11 .

Embodiment 6:

This embodiment proposes a method for sensing and detecting the concentration of enrofloxacin solution by using the device for measuring the extinction spectrum of noble metal nanoarrays in the second embodiment. The specific steps of the method are the same, the only difference is that the gold nano-arrays with periodic structure are different. In this embodiment, the gold nanoparticles are nano cylinders with a diameter of 200 nm and a height of 75 The spacing between the particles is 100 nm, and the scanning electron microscope (SEM) photograph thereof is shown in FIG. 9 .

Figure 12 shows that in Example 6, 20 microliters of enrofloxacin solutions with concentrations of 5 mg/L, 10 mg/L, 15 mg/L, 20 mg/L and 25 mg/L were added dropwise to the gold nanoarray, respectively. The extinction spectra of gold nanoarrays dropwise with enrofloxacin solutions at concentrations of 5 mg/L, 10 mg/L, 15 mg/L, 20 mg/L and 25 mg/L. Enrofloxacin solutions of different concentrations were prepared by formulating enrofloxacin powder with a purity greater than or equal to 98% (HPLC) with analytically pure ethanol solution. As can be seen from Figure 12, as the solution concentration of enrofloxacin increases, the position of the extinction peak in the extinction spectrum is red-shifted and the peak intensity is enhanced; and it is found that the position of the extinction peak in the extinction spectrum in Example 6 And the variation of the peak intensity is much smaller than the position of the extinction peak and the variation of the peak intensity in the extinction spectrum in Example 4, which is different from the localized surface plasmon caused by the increase in the particle spacing of the gold nanoarray in Example 6. Resonance (LSPR) weakened.

Figure 13 shows the concentration response curve diagram of different concentrations of enrofloxacin solution in Example VI. After obtaining the extinction spectrum of the gold nanoarray with the enrofloxacin solution added dropwise, the concentration of the dropwise enrofloxacin solution can be obtained according to FIG. 13 .

Claims (1)

1. A sensing detection method for a noble metal nanoarray extinction spectrum measuring device, the noble metal nanoarray extinction spectrum measuring device comprises a white light source, a beam lifter for changing the beam propagation path, a microscopic component, a The sample is a sample holder, an optical signal collector, a spectrometer and a computer terminal where the sample to be tested is placed horizontally, and the light beam emitted by the white light source is incident on the microscope assembly after changing the propagation path through the beam lifter, The focused beam emitted by the microscope assembly is incident on the sample to be tested, the optical signal collector receives the focused beam transmitted through the sample to be tested, and transmits the focused beam to the spectrometer, The spectrometer outputs spectral signals to the computer terminal; the beam lifter is composed of a vertically arranged first bracket, a first reflector arranged at the lower part of the first bracket, and a first mirror arranged in the The upper part of the first bracket is composed of a second reflector, the light beam emitted by the white light source is incident on the first reflector, and the light beam reflected by the first reflector is incident on the second reflector The light beam reflected by the second reflecting mirror is incident on the microscope assembly; the first reflecting mirror and the second reflecting mirror are both at a 45 degree angle to the horizontal plane, and the first reflecting mirror and the second reflecting mirror are at an angle of 45 degrees to the horizontal plane. The reflecting mirror and the second reflecting mirror are arranged in parallel, and the reflecting surface of the first reflecting mirror is directly opposite to the reflecting surface of the second reflecting mirror; The bracket, the semi-transparent mirror and the objective lens sequentially connected to the second bracket from top to bottom, connected to the second bracket and located on the propagation path of the light beam transmitted by the half-mirror It is composed of a light absorbing plate on the top of the glass, the half mirror and the objective lens are located directly above the sample holder, and the light beam emitted by the beam lifter is incident on the half mirror, The beam reflected by the half mirror is incident on the objective lens, the focused beam emitted by the objective lens is incident on the tested sample, and the beam transmitted by the half mirror is incident on the On the light-absorbing plate, the light-absorbing plate absorbs the light beam transmitted by the half-mirror; the half-mirror is at an angle of 45 degrees with the horizontal plane, and the reflection of the half-mirror The surface is opposite to the reflective surface of the second reflector; the light-absorbing plate is vertically arranged at a 45-degree angle to the half-mirror; the second bracket is also connected with a CCD camera, so The CCD camera is located just above the half mirror, the output end of the CCD camera is connected with the computer terminal, and the CCD camera obtains the The morphology of the noble metal nanoarray in the sample to be tested; the noble metal nanoarray extinction spectrum measurement device further includes a first three-dimensional position adjustment device for adjusting the position of the sample holder, and the first three-dimensional position adjustment device is composed of A first positioning plate, a first three-dimensional displacement platform mounted on the first positioning plate, and a first connecting rod connecting the first three-dimensional displacement platform and the sample holder, through the first three-dimensional displacement platform 3D displacement platform adjustment The position of the sample holder described in the section makes the sample to be tested located directly under the objective lens; the optical signal collector is composed of a fiber probe clamp and a fiber probe clamped by the fiber probe clamp, The fiber probe is placed vertically and its receiving end is located directly below the sample to be tested. The fiber probe receives the focused beam transmitted through the sample to be tested, and the output end of the fiber probe passes through the sample. The conducting fiber is connected to the input end of the spectrometer, and the fiber probe transmits the focused beam transmitted through the sample to be tested to the spectrometer; the noble metal nanoarray extinction spectrum measuring device also includes a device for adjusting the The second three-dimensional position adjustment device for the position of the optical signal collector, the second three-dimensional position adjustment device is composed of a second positioning plate, a second three-dimensional displacement platform mounted on the second positioning plate, and connecting the second positioning plate. The second three-dimensional displacement platform is composed of the second connecting rod of the optical fiber probe fixture, and the position of the optical fiber probe fixture is adjusted through the second three-dimensional displacement platform so that the optical fiber probe is located in the measured fiber probe. directly below the sample and close to the lower surface of the sample to be tested; the noble metal nano-array extinction spectrum measuring device also includes a base, the white light source and the spectrometer are placed on the base, and the first The bottom of a bracket and the bottom of the second bracket are respectively fixedly connected to the base, and the first positioning plate and the second positioning plate are respectively fixedly connected to the base; it is characterized in that: The sensing and detection of the concentration of organic solutions by using a noble metal nanoarray extinction spectrum measurement device specifically includes the following steps: ①Using electron beam etching technology to prepare a precious metal nanoarray with a specific pattern on the conductive glass deposited with a conductive film; then use the conductive glass with a specific pattern of precious metal nanoarrays as the sample to be tested; ②Turn on the white light source; then adjust the position of the optical fiber probe fixture through the second three-dimensional displacement platform, so that the receiving port of the optical fiber probe is located in the focal plane of the objective lens, so that the optical fiber can be clearly displayed on the monitor of the computer terminal through the objective lens and the CCD camera The receiving port of the probe; turn on the spectrometer again, and set the signal acquisition parameters; at this time, when the white light source is turned on, the spectral signal output by the spectrometer is the spectrum of the white light source, denoted as I(λ), and transmitted to the computer terminal, by the computer The terminal is saved; among them, λ represents the wavelength; ③Adjust the position of the optical fiber probe fixture through the second three-dimensional displacement platform, so that the optical fiber probe moves down vertically; then use the sample fixture to clamp the sample to be tested, and place the measured sample horizontally; then adjust the sample through the first three-dimensional displacement platform The position of the fixture is so that the precious metal nanoarray in the tested sample is located in the focal plane of the objective lens, and the image of the precious metal nanoarray in the tested sample is clearly displayed on the monitor of the computer terminal through the objective lens and the CCD camera; The 2D and 3D displacement platform adjusts the position of the fiber probe fixture, so that the fiber probe is located directly under the sample to be tested, and the receiving port of the fiber probe is as close as possible to the lower surface of the sample to be tested; at this time, when the white light source is turned on, the spectrum output by the spectrometer is The signal is the transmission spectrum of the noble metal nanoarray in the tested sample, denoted as T ₁ (λ), and transmitted to the computer terminal, where it is stored; 4. Turn off the white light source; take the spectral signal output by the spectrometer when the white light source is turned off at this time as the first background spectrum, denoted as B ₁ (λ), and transmit it to the computer terminal for storage by the computer terminal; ⑤ According to the definition _of extinction spectrum, the computer terminal calculates the _extinction spectrum E _{1 (} λ); ⑥ Take the organic solution to be tested and add it dropwise to the noble metal nanoarray in the sample to be tested; then take the spectral signal output by the spectrometer when the white light source is turned off at this time as the second background spectrum, denoted as B ₂ (λ), and transmitted to the computer terminal, and saved by the computer terminal; ⑦Turn on the white light source; at this time, when the white light source is turned on, the spectral signal output by the spectrometer is the transmission spectrum of the precious metal nanoarray with the organic solution to be tested dropwise added, denoted as T ₂ (λ), and transmitted to the computer terminal, by the computer terminal save; ⑧According to the definition of extinction spectrum, the computer terminal uses the formula E ₂ (λ)=I(λ)-T ₂ (λ)+B ₂ (λ) to calculate and obtain the extinction spectrum of the noble metal nano-array with the organic solution to be tested dropwise added E ₂ (λ); ⑨ Taking E ₁ (λ) as the reference spectrum, and then according to the change of the position or intensity of the extinction peak in E ₂ (λ) relative to the extinction peak in E ₁ (λ), the concentration of the organic solution to be tested is obtained.

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