阅读说明：本技术 一种基于金纳米颗粒的压力探测系统光学芯片 (Pressure detection system optical chip based on gold nanoparticles ) 是由 邢飞 韩雪 田敬坤 姬广民 于 2021-07-12 设计创作，主要内容包括：本发明公开了一种基于金纳米颗粒的压力探测系统光学芯片。该光学芯片是由石英玻璃/金纳米颗粒/微流体通道组成的多层膜耦合结构。其中所述的金纳米颗粒是通过等离子体溅射仪在石英玻璃上溅射制备的,能够自主控制溅射时间,从而可自主控制金纳米颗粒间的间隙。所述微流体通道介质层在与金纳米颗粒紧贴的一面具有微流体通道。通过本发明所提供的基于金纳米颗粒的压力探测系统光学芯片,能够实现对压力的变化进行实时监控,另一方面,由于金纳米颗粒对偏振光的依赖特性,提高了压力探测系统的灵敏度,能够检测小压力的变化,成功提供一个高灵敏度、超快速响应的压力探测系统。(The invention discloses an optical chip of a pressure detection system based on gold nanoparticles. The optical chip is a multilayer film coupling structure consisting of quartz glass/gold nanoparticles/microfluidic channels. The gold nanoparticles are prepared by sputtering on quartz glass through a plasma sputtering instrument, and the sputtering time can be controlled autonomously, so that the gaps among the gold nanoparticles can be controlled autonomously. The microfluidic channel medium layer is provided with a microfluidic channel on one surface clinging to the gold nanoparticles. The optical chip of the pressure detection system based on the gold nanoparticles can realize real-time monitoring on the pressure change, and on the other hand, the gold nanoparticles have the dependence on polarized light, so that the sensitivity of the pressure detection system is improved, the change of small pressure can be detected, and the pressure detection system with high sensitivity and ultra-fast response is successfully provided.)

1. An optical chip of a pressure detection system based on gold nanoparticles is formed by adhering a multilayer film coupling structure to a right-angle prism, and is characterized in that the multilayer film coupling structure is formed by quartz glass/gold nanoparticles/a microfluidic channel.

2. The optical chip of gold nanoparticle-based pressure detection system according to claim 1, wherein the height of said gold nanoparticle is 6-8 nm.

3. The optical chip of gold nanoparticle-based pressure sensing system according to claim 1, wherein said quartz glass has a size of 20mm by 20mm and a thickness of 1 to 1.5 mm.

4. The optical chip of gold nanoparticle-based pressure detection system according to claim 1, wherein the material of said microfluidic channel is polydimethylsiloxane.

5. The gold nanoparticle-based pressure detection system optical chip of claim 1, wherein said right-angle prism is an isosceles right triangular prism.

6. The method for preparing an optical chip of a pressure detection system based on gold nanoparticles according to any one of claims 1 to 5, comprising the steps of:

1) sputtering gold nanoparticles on quartz glass to prepare a sample;

2) preparing a patterned microfluidic channel using an existing mold;

3) erasing the gold nanoparticles sputtered on the quartz glass according to the shape and the size of the pattern of the microfluidic channel, putting the erased quartz glass with the gold nanoparticles into plasma for cleaning, and then bonding the quartz glass with the microfluidic channel with the pattern;

4) and bonding the other surface of the quartz glass with a triangular prism to form the optical chip of the pressure detection system based on the gold nanoparticles.

7. The method for preparing an optical chip for a pressure detection system based on gold nanoparticles as claimed in claim 6, wherein the step 1) is to sputter gold nanoparticles on quartz glass using a plasma sputter to prepare a sample.

8. The method for preparing an optical chip of a pressure detection system based on gold nanoparticles as claimed in claim 6, wherein the step 1) of preparing the sample by using the plasma sputtering apparatus can autonomously control the sputtering time, thereby autonomously controlling the gap between the gold nanoparticles.

9. A pressure detection device comprises a semiconductor laser, a polaroid, a quarter-wave plate, a microscope objective, a pressure detection system optical chip, a polarization splitting prism, an attenuation sheet, a diaphragm, a balance detector and a computer, wherein the pressure detection system optical chip is the pressure detection system optical chip based on gold nanoparticles in any one of claims 1 to 5; the semiconductor continuous laser with the wavelength of 532nm is used as an incident light source, incident light is adjusted into circularly polarized light through a polarizing film and a quarter wave plate, the circularly polarized light is focused through a microscope objective and then enters an optical chip of the pressure detection system for total internal reflection, reflected light is divided into p and s polarized light through a polarization beam splitter prism, finally, the p and s polarized light is simultaneously detected by a balance detector, and finally, a result is displayed on a computer in a voltage mode.

10. A method of pressure sensing for detecting humidity using the apparatus of claim 9, comprising:

1) respectively inserting a water inlet end and a water outlet end of an optical chip of the pressure detection system into a guide pipe, so that fluid can pass through the optical chip;

2) adjusting a laser, a polaroid, a quarter-wave plate and a microscope objective lens to obtain stable circular polarized light, enabling the stable circular polarized light to enter the optical chip of the pressure detection system, and generating total internal reflection at the multilayer film coupling structure;

3) recording optical power signals of p, s polarized light detected by a balance detector, wherein the difference of the optical power of the two polarized lights is presented in a voltage signal mode;

4) connecting the needle tube with the water inlet end guide tube, sealing the water outlet end by using a sealing device, and pushing the needle tube by hand to change the fluid pressure inside the optical chip so as to obtain a change curve related to pressure change;

5) changing the pressure, and repeating the step 4) to obtain a plurality of groups of experimental results.

Technical Field

The technology relates to the field of pressure detection and pressure sensing, in particular to a pressure detection system based on gold nanoparticles.

Background

The pressure sensor is the most common sensor in industrial practice, is widely applied to various industrial automatic control environments, and relates to a plurality of industries such as water conservancy and hydropower, railway transportation, intelligent buildings, production automatic control, aerospace and the like. When using a pressure sensor, there are several unavoidable errors, such as offset errors, sensitivity errors, linearity errors, hysteresis errors, etc. These errors are unavoidable with pressure sensors, and only high precision production equipment can be selected, using state-of-the-art techniques to reduce these errors.

Microfluidics refers to the technology of controlling, manipulating and detecting complex fluids at microscopic dimensions, and is a new and new interdisciplinary developed on the basis of microelectronics, micromachines, bioengineering and nanotechnology. With the development of biochip technology, microfluidics technology has also gained more and more attention as a key supporting technology of biochip. Unlike microelectronics, microfluidics does not emphasize the reduction in device size, it focuses on the construction of microfluidic channel systems to achieve a variety of complex microfluidic manipulation functions. The micro-fluidic chip has strong integration, can process a large number of different samples simultaneously and in parallel, and has the characteristics of fast analysis, low energy consumption, low pollution and the like. The invention combines gold nanoparticles with microfluidic technology to realize real-time detection of pressure.

Disclosure of Invention

The invention provides an optical chip of a pressure detection system based on gold nanoparticles, and aims to provide a pressure detection system with high sensitivity and ultra-fast response.

In order to achieve the above purpose, the present invention firstly provides an optical chip of a pressure detection system based on gold nanoparticles. The optical chip is composed of a right-angle prism and a multilayer film coupling structure adhered to the right-angle prism, and the multilayer film coupling structure is composed of quartz glass/gold nanoparticles/a microfluid channel medium layer.

In the optical chip, the height of the gold nanoparticles is 6-8 nm, the size of the quartz glass is 20mm x 20mm, the thickness of the quartz glass is 1-1.5mm, the right-angle prism is an isosceles right-angle triangular prism, and the material of the microfluidic channel is polydimethylsiloxane.

The preparation method of the pressure detection system optical chip based on the gold nanoparticles comprises the following steps:

1) firstly, preparing a mixed solution of alcohol, isopropanol and acetone, and then putting quartz glass into an ultrasonic cleaning machine for cleaning;

2) sputtering gold nanoparticles on quartz glass to prepare a sample;

3) preparing a patterned microfluidic channel using an existing mold;

4) erasing the gold nanoparticles sputtered on the quartz glass according to the shape and the size of the pattern of the microfluidic channel, putting the erased quartz glass with the gold nanoparticles into plasma for cleaning, and then bonding the quartz glass with the microfluidic channel with the pattern;

5) and bonding the other surface of the quartz glass with a triangular prism to form the optical chip of the pressure detection system based on the gold nanoparticles.

Step 2) sputtering gold nanoparticles on quartz glass by using a plasma sputtering instrument to prepare a sample; the step 2) is to prepare a sample by using a plasma sputtering instrument, so that the sputtering time can be controlled autonomously, and the gaps among the gold nanoparticles can be controlled autonomously; and 3) mixing the organic silicon elastomer substrate and the organic silicon elastomer curing agent in the microfluidic channel in the step 3) to obtain a prepolymer, pouring the prepolymer into a mould, and curing to obtain the microfluidic channel.

Total internal reflection, also known as total reflection, is defined as the angle of incidence θ when a beam of light is incident from an optically dense medium into an optically thinner medium₁Greater than critical angle theta_CThe total reflection phenomenon occurs, i.e. the refracted light disappears and the incident light is totally reflected. When total reflection occurs, the transmitted light intensity is zero, but the light intensity penetrates into the optically thinner medium for a short distance, propagates along the interface for a short distance, and returns to the optically denser medium, and the wave penetrating into the optically thinner medium is called evanescent wave. Evanescent waves are also called surface waves because they propagate along the interface of the medium.

In the multilayer film coupling structure described above, gold nanoparticles are sandwiched at the interface of a high refractive index medium 1 (quartz glass) and a low refractive index medium 2 (fluid in a microfluidic channel) to constitute a three-layer film structure. Under the condition of total reflection, the gold nanoparticles have polarization dependence on light absorption, namely, the gold nanoparticles have great absorption on s-polarized light and have small absorption on p-polarized light. When the refractive index of the medium 1 is fixed, the refractive index of the medium 2 is changed, the energy of reflected light changes along with the change of the medium 2, and the pressure detection system optical chip based on the gold nanoparticles is sensitive to the change of the refractive index of the medium 2 and can sense the change of the refractive index of the medium 2, so that the sensing of pressure change can be realized.

The invention provides a device for detecting pressure by utilizing the optical chip of the pressure detection system based on the gold nanoparticles, which comprises a semiconductor laser, a polaroid, a quarter-wave plate, a microscope objective, the optical chip of the pressure detection system, a polarization splitting prism, an attenuation sheet, a diaphragm, a balance detector and a computer, wherein laser with 532nm of emergent wavelength of the semiconductor laser is incident to the polaroid and the quarter-wave plate and is adjusted into circular polarization; the circularly polarized light is focused by the microscope objective and then enters the optical chip of the pressure detection system for total internal reflection; the light after total internal reflection is divided into p, s polarized light by the polarization beam splitter prism; the p, s polarized light is then received by the balanced detector and finally displayed as a voltage on the computer.

The step of detecting the flow rate of the fluid by using the device comprises the following steps:

1) respectively inserting a water inlet end and a water outlet end of an optical chip of the pressure detection system into a guide pipe, so that fluid can pass through the optical chip;

2) adjusting a laser, a polaroid, a quarter-wave plate and a microscope objective lens to obtain stable circular polarized light, enabling the stable circular polarized light to enter the optical chip of the pressure detection system, and generating total internal reflection at the multilayer film coupling structure;

3) recording optical power signals of p, s polarized light detected by a balance detector, wherein the difference of the optical power of the two polarized lights is presented in a voltage signal mode;

4) connecting the needle tube with the water inlet end guide tube, sealing the water outlet end by using a sealing device, and pushing the needle tube by hand to change the fluid pressure inside the optical chip so as to obtain a change curve related to pressure change;

5) changing the pressure, and repeating the step 4) to obtain a plurality of groups of experimental results.

Advantageous effects

The optical chip of the pressure detection system based on the gold nanoparticles can realize real-time monitoring on the pressure change, and on the other hand, the gold nanoparticles have the dependence on polarized light, so that the sensitivity of the pressure detection system is improved, the change of small pressure can be detected, and the pressure detection system with high sensitivity and ultra-fast response is successfully provided.

Drawings

FIG. 1 is a diagram of an optical chip of a pressure detection system for gold nanoparticles.

FIG. 2 is a light path diagram of a pressure detection system for gold nanoparticles.

FIG. 3 is a graph of experimental results of voltage versus pressure.

Detailed Description

An embodiment of the present invention provides an apparatus of a gold nanoparticle-based pressure detection system, the apparatus including:

FIG. 1 is an optical chip diagram of the detection system, which includes 101 isosceles right triangular prism, 102 PDMS, 103 Au nanoparticles, 104 microfluidic channels, 105 liquid inlet pipe, and 106 liquid outlet pipe.

The device comprises the following specific implementation steps:

1. preparation of sample by sputtering gold nanoparticles on quartz glass

Firstly, cleaning quartz glass; selecting a glass sheet with a proper size, wherein quartz glass with the size of 20 mm-20 mm and the thickness of 0.05mm is selected; preparing a mixed solution of alcohol, isopropanol and acetone, putting the prepared mixed solution into a beaker, then putting the beaker into an ultrasonic machine for ultrasonic cleaning for 25 minutes, cleaning the beaker by using ultrapure water after cleaning, and then flushing the ultrapure water on the surface of the quartz glass by using inert gas to obtain a clean quartz glass sheet; then, preparing a sample; and putting the cleaned quartz glass into a plasma sputtering instrument, setting the required time, starting a motor to vacuumize, and starting sputtering when proper discharge current is reached to obtain a whole gold nanoparticle sample.

2. Preparation of microfluidic channels

Mixing an organic silicon elastomer substrate and an organic silicon elastomer curing agent according to the proportion of 10:1 to obtain a polydimethylsiloxane prepolymer, pouring the obtained prepolymer into a mold with a pattern, curing for 2 hours at the temperature of 60 ℃ in a drying oven to obtain a micro-fluid channel with the pattern, and selecting micro-channels with proper patterns according to experimental requirements to punch holes at an inlet and an outlet respectively for standby.

3. Preparation of optical chip

Patterning the gold nanoparticle sample according to the pattern of the microchannel; firstly, according to the size, the dimension and the shape of a micro-channel, wiping a whole piece of gold nanoparticle quartz glass by using dust-free cloth, wiping out a shape with a size and a shape completely conforming to each other, then putting the wiped quartz glass and the micro-channel into a plasma machine for cleaning, cleaning for 2 minutes under the condition of 18W of power, then bonding the micro-channel with the pattern with the quartz glass with the gold nanoparticle to achieve permanent bonding, then respectively inserting a conduit with the diameter of about 0.5mm into an inlet and an outlet of the micro-channel to obtain a three-layer film coupling structure sequentially comprising a quartz glass/gold nanoparticle/micro-fluid channel medium layer, as shown in figure 1, and then bonding the three-layer film coupling structure with a right-angle prism by using a matching liquid with the same refractive index as that of the prism and the quartz glass, namely obtaining an optical film coupling formed by a plurality of films of the quartz glass/gold nanoparticle/micro-fluid channel medium layer The chip comprises 101 isosceles right triangular prisms, 102 polydimethylsiloxane, 103 gold nanoparticles, 104 microfluidic channels, 105 liquid inlet pipes and 106 liquid outlet pipes.

4. Arrangement in a pressure detection system

The device for assembling the pressure detection system by using the optical chip comprises a semiconductor laser 201, a polarizing plate 202, a quarter-wave plate 203, a microscope objective lens 204, a pressure detection system optical chip 205, a polarization beam splitter prism 206, a reflecting mirror 207, an attenuation plate 208, a diaphragm 209, a balance detector 210 and a computer 211, wherein the semiconductor laser is configured to emit laser with the wavelength of 532nm, enter the polarizing plate and the quarter-wave plate and is adjusted into circular polarization; the circular polarized light is focused by a microscope objective and then enters an optical chip of the pressure detection system for total internal reflection; the light after total internal reflection is divided into p, s polarized light through a polarization beam splitter prism; the p, s polarized light is then received by a balanced detector and finally displayed in the form of a voltage on a computer, thereby converting the optical signal into an electrical signal.

The device can obtain the pressure information through the obtained real-time voltage information, and the method comprises the following specific steps:

1) firstly, adjusting a laser, a polaroid, a quarter-wave plate and a microscope objective lens to obtain stable circular polarized light, enabling the stable circular polarized light to enter an optical chip of the pressure detection system, and generating total internal reflection at a multilayer film coupling structure;

2) recording optical power signals of p, s polarized light detected by a balance detector, wherein the difference of the optical power of the two polarized lights is presented in a voltage signal mode;

3) connecting the needle tube with the water inlet end guide tube, sealing the water outlet end by using a sealing device, and pushing the needle tube by hand to change the fluid pressure inside the optical chip so as to obtain a change curve related to the pressure change, wherein the change curve is shown in fig. 3;

4) changing the pressure, and repeating the step 4) to obtain a plurality of groups of experimental results.

As can be seen from fig. 3, the system can monitor the change of the fluid pressure in the microfluidic channel in real time, is sensitive to the pressure change, and can sense the change of the smaller pressure.