阅读说明：本技术 表面等离激元共振装置及制备方法、吸水量检测系统及方法 (Surface plasmon resonance device, preparation method thereof, water absorption amount detection system and method ) 是由 武清锋 翁雨燕 方亮 于 2019-11-19 设计创作，主要内容包括：本发明揭示了一种表面等离激元共振装置及制备方法、吸水量检测系统及方法,表面等离激元共振装置包括：衬底、位于衬底上的金属膜和位于金属膜上的高分子薄膜,所述高分子薄膜上设置有若干阵列分布的表面等离激元谐振腔,所述高分子薄膜在不同吸水量条件下的厚度不同。本发明中的表面等离激元共振装置用于检测高分子水凝胶的定向溶胀,结合表面等离激元共振(SPR),实现了密闭湿度环境内吸水量的原位无损检测,其应用范围较传统的湿度计和湿度指示硅胶有了明显的扩展。(The invention discloses a surface plasmon resonance device and a preparation method thereof, and a water absorption detection system and a method thereof, wherein the surface plasmon resonance device comprises: the surface plasmon resonance imaging device comprises a substrate, a metal film positioned on the substrate and a polymer film positioned on the metal film, wherein a plurality of surface plasmon resonance cavities distributed in an array mode are arranged on the polymer film, and the polymer film is different in thickness under the condition of different water absorption capacity. The surface plasmon resonance device is used for detecting the directional swelling of the polymer hydrogel, realizes the in-situ nondestructive detection of the water absorption amount in a closed humidity environment by combining the Surface Plasmon Resonance (SPR), and has an obviously expanded application range compared with the traditional hygrometer and humidity indicating silica gel.)

1. A surface plasmon resonance apparatus comprising: the surface plasmon resonance imaging device comprises a substrate, a metal film positioned on the substrate and a polymer film positioned on the metal film, wherein a plurality of surface plasmon resonance cavities distributed in an array mode are arranged on the polymer film, and the polymer film is different in thickness under the condition of different water absorption capacity.

2. The surface plasmon resonance apparatus of claim 1, wherein the depth of the surface plasmon resonance cavity is 75-200nm, the diameter is 100-500nm, and the array period of the surface plasmon resonance cavity is 300-600 nm.

3. The surface plasmon resonance apparatus of claim 1, wherein said polymer film is a polymer film having hydrophilic groups and hydrophobic groups, preferably said polymer film is a PEG film.

4. The surface plasmon resonance apparatus of claim 1, wherein said metal film is a gold film, a silver film or an aluminum film, and the metal film has a thickness of not less than 80 nm.

5. The method for preparing the surface plasmon resonance device according to claim 1, wherein the thickness of the bottom of the surface plasmon resonance cavity is 0-20 nm.

6. A method for preparing a surface plasmon resonance device is characterized by comprising the following steps:

providing a substrate;

sputtering a layer of metal film on the surface of the substrate;

spin-coating a polymer film on the metal film;

and carrying out nano-imprinting on the polymer film to form surface plasmon resonant cavities distributed in an array.

7. The method according to claim 6, wherein the nanoimprinting is performed using a PDMS soft template.

8. The method of claim 6, wherein the nanoimprint annealing is performed at a temperature of 110 ℃ to 130 ℃ and a pressure of 50 Bar to 70 Bar.

9. A water absorption capacity detection system, the system comprising:

a surface plasmon resonance device according to any of claims 1 to 5;

the spectrometer is used for detecting the movement of the SPR characteristic peak position of the surface plasmon resonance cavity caused by the thickness change of the polymer film under different water absorption amounts;

and the data processing unit is used for acquiring the corresponding water absorption amount according to the SPR characteristic peak position detected by the spectrometer.

10. A method for detecting a water absorption amount, comprising:

the surface plasmon resonance devices have different thicknesses under the conditions of different water absorption capacity;

detecting the movement of SPR characteristic peak positions of the surface plasmon resonance cavity caused by the thickness change of the polymer film under different water absorption amounts;

and acquiring corresponding water absorption amount according to the SPR characteristic peak position detected by the spectrometer.

Technical Field

The invention belongs to the technical field of water absorption detection, and particularly relates to a surface plasmon resonance device, a preparation method thereof, a water absorption detection system and a water absorption detection method.

Background

The traditional hygrometer can accurately reflect the humidity in the current open environment, but the humidity measurement in the closed or nondestructive testing environment still has certain limitations, and the reappearance of the change process depends on data storage, so that the practical application still has a lot of inconveniences. However, the humidity environment is a non-negligible factor in the production, processing and transportation process of food or medicine, and traceability from the source to the dining table becomes a focus of increasing attention. With the change of water absorption, different foods and medicines can show different water activities, and the water activities determine the chemical reactions and the microbial growth of the foods and the medicines. The low water activity can inhibit the chemical changes of food and medicines and stabilize the quality of the food and medicines, so that the monitoring of the cumulative effect of water absorption of the food and medicines from a source to a dining table in the food and medicine package is an important basis for the safety of the food and medicines.

Therefore, in order to solve the above technical problems, it is necessary to provide a surface plasmon resonance apparatus, a method for manufacturing the same, and a system and a method for detecting water absorption amount.

Disclosure of Invention

In view of the above, the present invention provides a surface plasmon resonance apparatus, a method for manufacturing the same, and a system and a method for detecting water absorption capacity, so as to meet the requirement of measuring water absorption capacity in a closed or nondestructive detection environment.

In order to achieve the above object, an embodiment of the present invention provides the following technical solutions:

a surface plasmon resonance apparatus comprising: the surface plasmon resonance imaging device comprises a substrate, a metal film positioned on the substrate and a polymer film positioned on the metal film, wherein a plurality of surface plasmon resonance cavities distributed in an array mode are arranged on the polymer film, and the polymer film is different in thickness under the condition of different water absorption capacity.

In one embodiment, the depth of the surface plasmon resonant cavity is 75-200nm, the diameter is 100-500nm, and the array period of the surface plasmon resonant cavity is 300-600 nm.

In one embodiment, the polymer film is a polymer film having a hydrophilic group and a hydrophobic group, and preferably, the polymer film is a PEG film.

In one embodiment, the metal film is a gold film, a silver film or an aluminum film, and the thickness of the metal film is not less than 80 nm.

In one embodiment, the thickness of the bottom of the surface plasmon resonant cavity is 0-20 nm.

A method for preparing a surface plasmon resonance device, comprising:

providing a substrate;

sputtering a layer of metal film on the surface of the substrate;

spin-coating a polymer film on the metal film;

and carrying out nano-imprinting on the polymer film to form surface plasmon resonant cavities distributed in an array.

In one embodiment, the nanoimprinting is performed using a PDMS soft template.

In one embodiment, the nanoimprint annealing temperature is 110-130 ℃ and the pressure is 50-70 Bar.

A water absorption capacity detection system, the system comprising:

the surface plasmon resonance device is the surface plasmon resonance device;

the spectrometer is used for detecting the movement of the SPR characteristic peak position of the surface plasmon resonance cavity caused by the thickness change of the polymer film under different water absorption amounts;

and the data processing unit is used for acquiring the corresponding water absorption amount according to the SPR characteristic peak position detected by the spectrometer.

A method of water absorption capacity detection, the method comprising:

the thickness of the surface plasmon resonance device is changed under the condition of different water absorption capacity;

detecting the movement of SPR characteristic peak positions of the surface plasmon resonance cavity caused by the thickness change of the polymer film under different water absorption amounts;

and acquiring corresponding water absorption amount according to the SPR characteristic peak position detected by the spectrometer.

Compared with the prior art, the invention has the following advantages:

the surface plasmon resonance device is used for detecting the directional swelling of the polymer hydrogel, realizes the in-situ nondestructive detection of the water absorption amount in a closed humidity environment by combining the Surface Plasmon Resonance (SPR), and has an obviously expanded application range compared with the traditional hygrometer and humidity indicating silica gel;

the PEG-based hydrogel has the food-grade safety characteristic, and can realize in-situ nondestructive detection of the humidity environment in food and medicine packages;

the nano-level hydrogel polymer structure and SPR in the invention enhance the spectrum, so that the high-sensitivity detection of water absorption is ensured;

the COMSOL simulation in the invention corresponds to the spectral response caused by the change of the water absorption height in practice, and the precision is higher;

the height change of the high-molecular hydrogel in the invention when swelling is closely related to the humidity environment contacted with the high-molecular hydrogel, the humidity environment experienced by the sample can be traced, and the water content of the surface of the sample is recorded.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments described in the present application, and other drawings can be obtained by those skilled in the art without creative efforts.

Fig. 1 is a schematic structural diagram of a surface plasmon resonance apparatus according to an embodiment of the present invention;

FIG. 2 is a diagram of a model of hydrogel orientation in accordance with an embodiment of the present invention;

FIG. 3, a is a surface topography of a polymeric ribbon before swelling in accordance with an embodiment of the present invention;

FIG. 3, b is a surface topography of the polymer strip after swelling according to an embodiment of the present invention;

in FIG. 3, c is a height histogram corresponding to the swelling of the polymer bands in an embodiment of the present invention;

in fig. 3, d is a surface topography diagram of the polymer strip after being dried by high purity nitrogen in an embodiment of the present invention;

FIG. 4 is a graph of actual measurements of reflectance spectra of SPR characteristic peaks in an embodiment of the present invention;

FIG. 5 is a graph of simulation results of a reflectance spectrum of an SPR characteristic peak in an embodiment of the present invention;

FIG. 6 is a diagram illustrating the structure of Comsol simulation according to an embodiment of the present invention;

FIG. 7 is a surface SEM topography of a surface plasmon resonance apparatus in an embodiment of the invention.

Detailed Description

The present invention will be described in detail below with reference to embodiments shown in the drawings. The embodiments are not intended to limit the present invention, and structural, methodological, or functional changes made by those skilled in the art according to the embodiments are included in the scope of the present invention.

Referring to fig. 1, a surface plasmon resonance apparatus according to an embodiment of the present invention includes: a substrate 1, a metal film 2 on the substrate 1, and a polymer film 3 on the metal film 2.

The metal film 2 is a gold film, a silver film or an aluminum film, the thickness of the metal film 2 is not less than 80nm, and preferably, the metal film is a gold film in this embodiment.

The polymer film is made of polymer material with hydrophilic group and hydrophobic group, such as PEG material, and the polymerization degree of PEG is not less than 4000. In other embodiments, the PEG material is not limited to be used, and other polymer materials having hydrophilic groups and hydrophobic groups may be used.

Preferably, the polymer film 3 in this embodiment is a polyurethane-ureido polyethylene glycol PUU4K-12 film, and the structural formula of PUU4K-12 is:

the polymer film 3 is provided with a plurality of surface plasmon resonators 31 distributed in an array, preferably, the thickness of the bottom of the surface plasmon resonator 31 is 0-20 nm, the depth of the surface plasmon resonator 31 is 75-200nm, the diameter is 100-500nm, and the array period of the surface plasmon resonator 31 is 300-600 nm.

The thickness of the polymer film 3 is different under the condition of different water absorption capacity, so that the corresponding water absorption capacity can be obtained by measuring the thickness of the polymer film.

The principle about the surface plasmon resonance apparatus is specifically as follows:

as shown in fig. 2, taking PEG material as an example, annealing temperature is controlled at 120 degrees celsius, and hydrogen bonds are broken, so that surface plasmon resonator 31 only undergoes directional swelling perpendicular to the substrate when it encounters water. The crystalline segment PEG grows rapidly along the line direction of the nano-strip, and the main chain of the high-molecular hydrogel is arranged perpendicular to the substrate. A PEG platelet-alkyl chain-PEG platelet structure is formed in the height direction of the nanobelt of the polymer hydrogel, after the PEG platelet absorbs water, because the alkyl chain locks the water, an anisotropic swelling behavior in the direction perpendicular to the substrate is formed, so that the polymer is ensured to expand only in the z direction perpendicular to the substrate when meeting the water, and the sensitivity of the polymer hydrogel for water absorption detection is greatly improved.

Meanwhile, the water absorption and swelling behavior of the stripe-type array-distributed surface plasmon resonant cavity 31 is characterized by the water phase atomic force. In fig. 3, a and b are surface topography diagrams of the polymer strip resonant cavity with the line width of 500nm, and from an AFM height diagram, it can be seen that the width of the polymer hydrogel nanoribbon is 500nm, the height is 110nm, and after being swelled by adding water, the height becomes 165nm and the width becomes 532 nm. As shown in FIG. 3 c, before and after swelling, we found that the band width changed by 6% and the height changed by 50%, swollen, initial, Dry in the order from left to right in FIG. 3 c. After being dried by high-purity nitrogen, the shape recovery rate reaches about 85% as can be seen from d of FIG. 3.

The method for preparing the surface plasmon resonance device in the embodiment comprises the following steps:

providing a substrate 1, wherein the substrate 1 is a quartz substrate;

sputtering a layer of metal film 2 on the surface of a substrate 1;

a layer of polymer film 3 is spin-coated on the metal film 2, the concentration of the polymer aqueous solution is 15-20mg/ml, and the spin-coating rotating speed is 4000-;

and performing nano-imprinting on the polymer film 3 by adopting a PDMS soft template, wherein the annealing temperature of the nano-imprinting is 110-130 ℃ and the pressure is 50-70Bar, so as to form the surface plasmon resonant cavity 31 distributed in an array.

In the embodiment, the surface of the hydrogel is subjected to micro-nano structuring by a nano-imprinting technology, and the swelling deformation of the hydrogel is concentrated on one dimension, so that the sensitivity of the swelling phenomenon on the surface structure change is improved. On this basis, in order to amplify the effect of swelling with water and realize a spectrally nondestructive test, a gold film 2 is sputtered on the substrate 1 to realize introduction of Surface Plasmon Resonance (SPR).

Therefore, selecting the gold film 2 as a substrate and introducing SPR; constructing a food-grade safe hydrogel PEG micro-nano structure resonant cavity on the surface of the hydrogel PEG micro-nano structure resonant cavity by a nanoimprint technology; due to the directional expansion of the high-orientation-degree macromolecules of the chain segment, the size of the built resonant cavity responds to the peak position of the specific water absorption capacity, so that the reflection spectrum characterization of the surface by a spectrometer can be realized, and then the movement change of the SPR characteristic peak before and after the water absorption response is obtained in a non-destructive manner in situ.

In another embodiment of the present invention, a water absorption amount detecting system is disclosed, which includes:

a surface plasmon resonance device;

the spectrometer is used for detecting the movement of the SPR characteristic peak position of the surface plasmon resonance cavity 31 caused by the thickness change of the polymer film under different water absorption amounts;

and the data processing unit is used for acquiring the corresponding water absorption amount according to the SPR characteristic peak position detected by the spectrometer.

The invention also discloses a water absorption amount detection method in another embodiment, which comprises the following steps:

the surface plasmon resonance devices have different thicknesses under the conditions of different water absorption capacity;

detecting the movement of the SPR characteristic peak position of the surface plasmon resonance cavity 31 caused by the change of the polymer film under different water absorption amounts;

and acquiring corresponding water absorption amount according to the SPR characteristic peak position detected by the spectrometer.

The surface plasmon resonance device and the preparation method are discussed in detail in the foregoing embodiments, and are not described herein again.

And the surface plasmon resonance device measures the micro-region reflection spectrum of the reflection surface of the surface plasmon resonance cavity 31 before and after swelling, and obtains the change condition of the SPR characteristic peak position.

After the surface plasmon resonance cavity 31 is high when meeting water, the SPR characteristic peak of the surface plasmon resonance cavity is changed along with the water length, so that the SPR characteristic peak is reflected to the reflection spectrum, and therefore the in-situ nondestructive detection of the water absorption capacity can be realized through the movement of the characteristic peak position on the reflection spectrum. The reflection spectrum of the SPR optical resonant cavity is characterized by the reflection spectrum mode of a spectrometer, and as a result, as shown in FIG. 4, it can be clearly found that the height of the polymer resonant cavity 31 before and after water absorption is changed from 1h to 1.5h, and simultaneously, the height is changed from 680nm to 705nm along with the movement of the characteristic peak position.

For verification, Comsol simulation is adopted, the movement of the characteristic peak position is calculated, and a simulation structural design diagram is shown in fig. 6. Under the condition of identical structure, as shown in fig. 5, before and after the height of the polymer resonator 31 is changed, the characteristic peak also moves from 670nm to 700nm, and the comparison between the characteristic peak position and the moving degree is realized.

The surface topography of the surface plasmon resonance apparatus was characterized by Scanning Electron Microscopy (SEM), as shown in fig. 7. The water-absorbing material in the surface plasmon resonant cavity 31 absorbs moisture and expands, so that the size of the surface plasmon resonant cavity 31 is changed and reflected on the movement of the spectral reflection valley, and the sensitivity and the accuracy of the surface plasmon resonance device on the water absorption are reflected.

Therefore, in view of the above description, it has been found that the water absorption amount in the environment with different water absorption amounts, the thickness of the polymer thin film in the surface plasmon resonance apparatus, and the SPR characteristic peak position corresponding to the polymer thin film with different thicknesses are in one-to-one correspondence, and based on the correspondence, the detection of the corresponding water absorption amount can be realized by measuring the obtained SPR characteristic peak position.

According to the technical scheme, the invention has the following beneficial effects:

the surface plasmon resonance device is used for detecting the directional swelling of the polymer hydrogel, realizes the in-situ nondestructive detection of the water absorption amount in a closed humidity environment by combining the Surface Plasmon Resonance (SPR), and has an obviously expanded application range compared with the traditional hygrometer and humidity indicating silica gel;

the PEG-based hydrogel has the food-grade safety characteristic, and can realize in-situ nondestructive detection of the humidity environment in food and medicine packages;

the nano-level hydrogel polymer structure and SPR in the invention enhance the spectrum, so that the high-sensitivity detection of water absorption is ensured;

the COMSOL simulation in the invention corresponds to the spectral response caused by the change of the water absorption height in practice, and the precision is higher;

the height change of the high-molecular hydrogel in the invention when swelling is closely related to the humidity environment contacted with the high-molecular hydrogel, the humidity environment experienced by the sample can be traced, and the water content of the surface of the sample is recorded.

It will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrative embodiments, and that the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Any reference sign in a claim should not be construed as limiting the claim concerned.

Furthermore, it should be understood that although the present description refers to embodiments, not every embodiment may contain only a single embodiment, and such description is for clarity only, and those skilled in the art should integrate the description, and the embodiments may be combined as appropriate to form other embodiments understood by those skilled in the art.