CN106947018A - A kind of high-performance and highly controllable hud typed trace sensor and preparation method and purposes - Google Patents

Abstract

The invention provides a kind of high-performance and highly controllable hud typed trace sensor and preparation method and purposes, preparation process is as follows：The preparation of step 1, amino functional Nano particles of silicon dioxide；The preparation of step 2, functionalization SiO2/Ag nano-complex particles；The preparation of step 3, nucleocapsid SiO2/Ag/MIPs.SERS technologies are combined by the present invention with surface molecule print technology so that the product of preparation has the high sensitivity of SERS Detection Techniques and MIT high selectivity concurrently；Present invention selection molecular imprinted polymer on surface (SMIPs) promotes the selectivity of tradition SERS backing materials, expands the application of SERS detections.

Description

A high-performance and highly controllable core-shell imprinted sensor and its preparation method and use

technical field

The invention relates to the preparation and application of a high-performance and highly controllable core-shell imprinted sensor, belonging to the technical field of new materials.

Background technique

In recent years, organic pollutants have seriously endangered the global environment, threatening ecological balance and human health. However, most organic pollutants only exist in trace or ultra-trace levels. Traditional detection methods are time-consuming, complicated, and difficult to meet the sensitivity requirements, making accurate detection relatively difficult. Therefore, there is an urgent need to develop effective and sensitive detection methods.

Surface-enhanced Raman scattering (SERS) is an efficient analytical method that enables tracking detection. When the probe molecule is on or near the surface of the SERS substrate, the Raman signal of the probe molecule will be significantly enhanced. Generally speaking, there are two enhancement mechanisms of SERS, which are physical enhancement and chemical enhancement. The former is due to the enhancement of the local electromagnetic field caused by the plasmon oscillation on the surface of the SERS active substrate, which makes the Raman signal significantly enhanced. The latter is due to the chemical interaction between the probe molecule and the SERS substrate, which increases the polarizability of the probe molecule and leads to the enhancement of the Raman signal. Usually, these two enhancement mechanisms work together to lead to Raman signal enhancement, but there are different contribution ratios in different systems.

At present, noble metal nanoparticles (such as gold and silver) are widely used in the preparation of SERS matrix materials, mainly because noble metal nanoparticles have excellent optical and electrical properties, and have strong characteristic absorption in the visible region, which is largely attributed to due to its surface plasmon resonance. Among them, silver is the most widely used, mainly because the SERS signal enhancement of silver is the most obvious, and the chemical properties of silver are stable, and it has broad-spectrum antibacterial properties and potential anti-cancer applications. At present, SERS technology has been widely used in the detection of trace chemical substances, such as proteins, medical drugs, food additives and identification of various biological components. However, the current research on SERS mainly focuses on the morphology of host materials or the improvement of SERS performance, while ignoring the lack of specific selectivity of traditional host materials. Therefore, improving the selectivity of traditional SERS substrate materials will expand the application of SERS detection.

Recently, molecularly imprinted polymers (MIPs) have been widely used in chromatographic separation, membrane separation, solid phase extraction, controlled drug release, chemical sensing, and environmental detection due to their excellent characteristics such as specific recognition, predetermined structure and activity, and wide practicability. attention. Molecular imprinting technology is that when template molecules (imprinted molecules) are in contact with polymer monomers, multiple action sites will be formed, and specific recognition sites will be generated through the polymerization process. Site cavities with matching spatial configurations, such cavities will have selective recognition properties for template molecules and their analogs. Among MIPs materials, surface molecularly imprinted polymers (SMIPs) can better solve the shortcomings of traditional MIPs, such as poor binding ability, poor binding kinetics, deep embedding of active sites, and poor removal of template molecules. Thoroughly, gradually attracting more and more scientific workers of all ages.

In order to improve the selectivity of SERS substrate materials, MIPs-SERS sensors were prepared by combining SERS technology with molecular imprinting technology (MIT). For example, Kamra et al. prepared a novel biosensor for the determination of melamine in whole milk by combining molecularly imprinted polymers and surface-enhanced Raman spectroscopy (MIPs-SERS). Xiao et al. established a MIP-based chemical sensor to detect nicotine by SERS. These methods demonstrate the excellent performance of MIPs-SERS technology. Therefore, it is feasible to combine the high-sensitivity SERS detection technology with the high-selectivity MIT to prepare MIPs-SERS sensors to detect organic pollutants in water.

Contents of the invention

The sensor is mainly synthesized through three-step reactions. First, amino-functionalized silica nanoparticles were synthesized. Mix ethanol, water and NH ₃ ·H ₂ O evenly, slowly add tetraethyl orthosilicate (TEOS) dropwise and stir mechanically. Then add 3-aminopropyltriethoxysilane (APTES) into the solution, and continue to stir the mixture. After the reaction, centrifuge, wash with ethanol, and dry; then, disperse the amino-functionalized silica nanoparticles into the mixed solution of ethanol/water, add silver nitrate solution, then drop polyvinylpyrrolidone (PVP) solution, continue Stir magnetically in the dark. Subsequently, ethanolamine was added to the mixed system, and the temperature was raised to continue stirring. Centrifuge and wash repeatedly with water and ethanol to remove unreacted reactants. The final product was dried under vacuum at room temperature; finally, rhodamine (R6G), acrylamide (AM) and ethylene glycol dimethacrylate (EGDMA) were added to the above solution, and oxygen was completely purged with _N2 . Add azobisisobutyronitrile (AIBN), seal the mixing system, put it into a constant temperature water bath shaker, and react at 50°C for several hours, then raise it to 60°C to continue the reaction. The product was collected by centrifugation, washed several times with ethanol to remove unreacted reactants, and further washed by Soxhlet extraction.

The present invention is achieved through the following technical solutions:

A high-performance and highly controllable core-shell imprinted sensor, the sensor is composed of amino-functionalized silica, Ag, and imprinted layers, and the Ag is loaded on the amino-functionalized silica to form SiO ₂ /Ag nanocomposite particles; the imprinted layer is polymerized from acrylamide (AM), ethylene glycol dimethacrylate (EGDMA) and azobisisobutyronitrile (AIBN), and the imprinted layer Covering the functionalized SiO ₂ /Ag nanocomposite particles, the imprinted layer has a thickness of 40-170 nm.

A method for preparing a high-performance and highly controllable core-shell type imprinted sensor, the steps are as follows:

Step 1, preparation of amino-functionalized silica nanoparticles

Add ammonia water to the ethanol/water mixed solution, under stirring conditions, add TEOS, stir, then add APTES, continue stirring reaction; centrifuge the product, wash and dry to obtain amino-functionalized silica nanoparticles, ready for use;

Step 2. Preparation of functionalized SiO ₂ /Ag nanocomposite particles

Disperse amino-functionalized silica nanoparticles in ethanol/water mixed solution, add silver nitrate solution and PVP solution, and stir magnetically in a dark environment; then, add EA, raise the temperature and continue stirring reaction; centrifuge the solid product, Washing and drying to obtain functionalized SiO ₂ /Ag nanocomposite particles, ready for use;

Step 3. Preparation of core-shell SiO ₂ /Ag/MIPs

Disperse the functionalized SiO ₂ /Ag nanocomposite particles into acetonitrile, add rhodamine 6G, AM and EGDMA, and remove oxygen with inert gas; then, add AIBN, seal, place in a constant temperature water bath shaker, set at 50°C Carry out a prepolymerization reaction, then raise the temperature to 60°C to continue the reaction; the solid product is centrifuged, washed, and dried to obtain core-shell SiO ₂ /Ag/MIPs, that is, the high-performance and highly controllable core-shell imprinted sensor.

In step 1, the volume ratio of the ethanol/water mixed solution, ammonia water, TEOS, and APTES is 80-100:10-20:9:1-3; in the ethanol/water mixed solution, the volume ratio of ethanol to water The ratio is 4:5; the time for stirring A is 4-6 hours, and the time for continuing to stir the reaction is 10-14 hours.

In step 2, the dosage ratio of the amino-functionalized silica nanoparticles, ethanol/water mixed solution, silver nitrate solution, PVP solution, and EA is 100mg: 50mL: 5mL: 4-6mL: 0.4-0.6mL; The concentration of the silver nitrate solution is 0.1mol/L, the concentration of the PVP solution is 0.2mol/L, and in the ethanol/water mixed solution, the volume ratio of ethanol and water is 4:1; The time for stirring is 4-6 hours, and the time for continuing stirring is 3-5 hours.

In step 3, the dosage ratio of the functionalized SiO ₂ /Ag nanocomposite particles, acetonitrile, rhodamine 6G, AM, EGDMA, AIBN is 100mg: 50-70mL: 0.05-0.15mmol: 0.3-0.5mmol: 0.237-0.396 mL: 9-11 mg; the inert gas is nitrogen.

In steps 1-3, the washings are performed three times with ethanol and water respectively.

The as-prepared high performance and highly controllable core-shell imprinted sensor was used for the selective adsorption of rhodamine 6G.

The preparation method of the corresponding non-imprinted polymer of the present invention is similar to the synthesis method as above, but without adding R6G.

Technical advantage of the present invention:

The present invention combines SERS technology with surface molecular imprinting technology, so that the prepared product has both the high sensitivity of SERS detection technology and the high selectivity of MIT; the present invention selects surface molecularly imprinted polymers (SMIPs) to promote the traditional SERS substrate materials. Selectivity expands the application range of SERS detection; in the present invention, the thickness of the shell can be controlled by changing the amount of cross-linking agent. Molecularly imprinted polymers (MIPs) have attracted much attention in recent years. Because the material avoids the disadvantages of traditional MIPs, it can bind template molecules and specifically recognize holes. Combining it with SERS detection technology is of great significance to the development of SERS technology. The invention shows that the surface-enhanced Raman scattering detection has broad application prospects in the technical field of new materials.

Description of drawings

Figure 1: TEM images of prepared SiO ₂ /Ag/MIPs with different imprinted layer thicknesses: 40nm (a), 100nm (b), 170nm (c);

Figure 2: Fourier transform infrared spectra of SiO ₂ /Ag/MPS and SiO ₂ /Ag/MIPs, curve a is SiO ₂ /Ag/MPS, curve b is SiO ₂ /Ag/MIPs;

Figure 3: SERS detection of 10 ^-6 mol/L R6G adsorbed on SiO ₂ /Ag/MIPs with different thicknesses: 40nm (a), 100nm (b), 170nm (c);

Figure 4: SERS spectra (a) of SiO ₂ /Ag/MIPs adsorbed with different concentrations of R6G and the linear relationship between Raman intensity and R6G concentration (b);

Fig. 5: SERS spectral selective detection of SiO ₂ /Ag/MIPs in 10 ^–6 mol/L R6G (a), RB (b) and CV (c).

detailed description

The present invention will be further described below in conjunction with specific implementation examples.

Example 1:

(1) Synthesis of amino-functionalized silica nanoparticles:

In a 100 mL one-necked flask, add 90 mL of ethanol and water mixed solvent (volume ratio 4:5), and add 15 mL of NH ₃ ·H ₂ O. Under the condition of stirring, 9mLTEOS was added, and the stirring was continued for 5h. 2 mL of APTES was added and stirring was continued for 12 h. The product was separated by centrifugation, washed and dried for use.

(2) Synthesis of functionalized SiO ₂ /Ag nanocomposite particles:

In a 100mL single-necked flask, disperse 100mg of amino-functionalized silica nanoparticles in 50mL of ethanol/water mixed solvent (v/v=4:1), add 5mL of silver nitrate solution with a concentration of 0.1mol/L, and then add 5mL of PVP solution with a concentration of 0.2mol/L was stirred magnetically for 4h in a dark environment. Then, 500 μL of EA was added, and the temperature was increased to 50° C. and stirring was continued for 5 h. Centrifuge, wash repeatedly with water and ethanol to remove unreacted reactants, and the final product is vacuum-dried at room temperature.

(3) Preparation of core-shell SiO ₂ /Ag/MIPs

In a 100 mL single-necked flask, 100 mg of MPS-modified SiO ₂ /Ag nanoparticles were dispersed in 60 mL of acetonitrile. Add 0.1 mmol R6G, 0.4 mmol AM, and 237 μL of EGDMA, and blow N for ₁₅ min at room temperature to completely remove oxygen. Subsequently, 10 mg of AIBN was added, sealed, placed in a constant temperature water bath shaker, and the reaction temperature was set at 50° C., and the reaction time was 6 hours. Then it was raised to 60°C and reacted for another 24h. The collected product was centrifuged and washed with ethanol to remove unreacted reactants, further washed with Soxhlet extract

In the reaction system described in step (1), the volume ratio of TEOS and mixed solvent is 9mL:90mL, the volume ratio of TEOS and ammonia water is 9mL:15mL, and the volume ratio of TEOS and APTES is 9mL:2mL. The washings described in the steps are all washed three times with ethanol and water respectively.

In the reaction system described in step (2), the volume ratio of the silver nitrate solution to the PVP is 1 mL:1 mL, and the volume ratio of the silver nitrate solution to the EA solution is 1 mL:100 μL.

In the reaction system described in step (3), the mass volume ratio of SiO ₂ /Ag nanoparticles to acetonitrile solution is 100mg:60mL, the mass ratio of SiO ₂ /Ag nanoparticles to AIBN is 100mg:10mg, and the SiO ₂ /Ag nano The mass molar ratio of particles to R6G solution is 100mg:0.1mmol, the mass molar ratio of SiO ₂ /Ag nanoparticles to AM solution is 100mg:0.4mmol, and the mass volume ratio of SiO ₂ /Ag nanoparticles to EGDMA solution is 100mg:237μL . The washings described in the steps are all washed three times with ethanol and water respectively.

The preparation method of the corresponding non-imprinted polymer of the present invention is similar to the synthesis method as above, but without adding R6G.

Example 2:

(1) Synthesis of amino-functionalized silica nanoparticles:

In a 100 mL one-necked flask, add 80 mL of ethanol and water mixed solvent (volume ratio 4:5), and add 10 mL of NH ₃ ·H ₂ O. Under stirring conditions, 8mL TEOS was added and stirring continued for 4h. Add 1 mL of APTES and continue stirring for 10 h. The product was separated by centrifugation, washed and dried for use.

(2) Synthesis of functionalized SiO ₂ /Ag nanocomposite particles:

In a 100mL single-necked flask, disperse 100mg of amino-functionalized silica nanoparticles in 50mL of ethanol/water mixed solvent (v/v=4:1), add 4mL of silver nitrate solution with a concentration of 0.1mol/L, and then add 4mL of PVP solution with a concentration of 0.2mol/L was stirred magnetically for 3h in a dark environment. Then, 400 μL of EA was added, and the temperature was increased to 50° C. and stirring was continued for 4 h. Centrifuge, wash repeatedly with water and ethanol to remove unreacted reactants, and the final product is vacuum-dried at room temperature.

(3) Preparation of core-shell SiO ₂ /Ag/MIPs

In a 100 mL one-necked flask, 100 mg of MPS-modified SiO ₂ /Ag nanoparticles were dispersed in 50 mL of acetonitrile. Add 0.05 mmol R6G, 0.3 mmol AM, and 316 μL of EGDMA, and blow N ₂ at room temperature for 15 min to completely remove oxygen. Subsequently, 9 mg of AIBN was added, sealed, placed in a constant temperature water bath shaker, and the reaction temperature was set at 50° C., and the reaction time was 5 hours. Then it was raised to 60°C and reacted for another 20h. The collected product was centrifuged and washed with ethanol to remove unreacted reactants, further washed with Soxhlet extract

In the reaction system described in step (1), the volume ratio of TEOS and mixed solvent is 8mL:80mL, the volume ratio of TEOS and ammonia water is 8mL:10mL, and the volume ratio of TEOS and APTES is 8mL:1mL. The washings described in the steps are all washed three times with ethanol and water respectively.

In the reaction system described in step (2), the volume ratio of the silver nitrate solution to the PVP is 1 mL:1 mL, and the volume ratio of the silver nitrate solution to the EA solution is 1 mL:100 μL.

In the reaction system described in step (3), the mass volume ratio of SiO ₂ /Ag nanoparticles to acetonitrile solution is 100mg:50mL, the mass ratio of SiO ₂ /Ag nanoparticles to AIBN is 100mg:9mg, and the SiO ₂ /Ag nano The mass molar ratio of SiO 2 /Ag nanoparticles to AM solution is 100mg:0.05mmol, the mass molar ratio of SiO ₂ /Ag nanoparticles to AM solution is 100mg:0.3mmol, and the mass volume ratio of SiO ₂ /Ag nanoparticles to EGDMA solution is 100mg:316μL . The washings described in the steps are all washed three times with ethanol and water respectively.

The preparation method of the corresponding non-imprinted polymer of the present invention is similar to the synthesis method as above, but without adding R6G.

Example 3:

(1) Synthesis of amino-functionalized silica nanoparticles:

In a 100 mL one-necked flask, add 100 mL of ethanol and water mixed solvent (volume ratio 4:5), and add 20 mL of NH ₃ ·H ₂ O. Under the condition of stirring, 10mL TEOS was added, and the stirring was continued for 6h. Add 3mL APTES and continue stirring for 14h. The product was separated by centrifugation, washed and dried for use.

(2) Synthesis of functionalized SiO ₂ /Ag nanocomposite particles:

In a 100mL single-necked flask, disperse 100mg of amino-functionalized silica nanoparticles in 50mL of ethanol/water mixed solvent (v/v=4:1), add 6mL of silver nitrate solution with a concentration of 0.1mol/L, and then add 6mL of PVP solution with a concentration of 0.2mol/L was stirred magnetically for 5h in a dark environment. Then, 600 μL of EA was added, and the temperature was increased to 50° C. and stirring was continued for 6 h. Centrifuge, wash repeatedly with water and ethanol to remove unreacted reactants, and the final product is vacuum-dried at room temperature.

(3) Preparation of core-shell SiO ₂ /Ag/MIPs

In a 100 mL single-necked flask, 100 mg of MPS-modified SiO ₂ /Ag nanoparticles were dispersed in 70 mL of acetonitrile. Add 0.15 mmol R6G, 0.5 mmol AM, and 396 μL of EGDMA, and blow _N2 at room temperature for 15 min to completely remove oxygen. Subsequently, 11 mg of AIBN was added, sealed, placed in a constant temperature water bath shaker, and the reaction temperature was set at 50° C., and the reaction time was 7 hours. Then it was raised to 60°C and reacted for another 28h. The collected product was centrifuged and washed with ethanol to remove unreacted reactants, further washed with Soxhlet extract

In the reaction system described in step (1), the volume ratio of TEOS and mixed solvent is 10mL:100mL, the volume ratio of TEOS and ammonia water is 10mL:20mL, and the volume ratio of TEOS and APTES is 10mL:3mL. The washings described in the steps are all washed three times with ethanol and water respectively.

In the reaction system described in step (2), the volume ratio of the silver nitrate solution to the PVP is 1 mL:1 mL, and the volume ratio of the silver nitrate solution to the EA solution is 1 mL:100 μL.

In the reaction system described in step (3), the mass volume ratio of SiO ₂ /Ag nanoparticles to acetonitrile solution is 100mg:70mL, the mass ratio of SiO ₂ /Ag nanoparticles to AIBN is 100mg:11mg, and the SiO ₂ /Ag nano The mass molar ratio of SiO 2 /Ag nanoparticles to AM solution is 100mg:0.15mmol, the mass molar ratio of SiO ₂ /Ag nanoparticles to AM solution is 100mg:0.5mmol, and the mass volume ratio of SiO ₂ /Ag nanoparticles to EGDMA solution is 100mg:396μL . The washings described in the steps are all washed three times with ethanol and water respectively.

The preparation method of the corresponding non-imprinted polymer of the present invention is similar to the synthesis method as above, but without adding R6G.

Figure 1: TEM images of the prepared SiO ₂ /Ag/MIPs. The Ag is loaded on amino-functionalized silica to form SiO ₂ /Ag nanocomposite particles; the imprinted layer is made of acrylamide (AM), ethylene glycol dimethacrylate (EGDMA) and azobisiso Butyronitrile (AIBN) is polymerized, and the imprinted layer is coated on the functionalized SiO ₂ /Ag nanocomposite particles, and the thickness of the imprinted layer is 40-170nm. From the figure, we can see different imprinted layer thicknesses: 40nm (a), 100nm (b), 170nm (c);

Figure 2: Fourier transform infrared spectra of _SiO2 /Ag/MPS and _SiO2 /Ag/MIPs. From the figure, we can see that the imprinted polymer layer has been successfully wrapped on the SiO ₂ /Ag surface;

Figure 3: SERS detection of 10 ^-6 mol/L R6G adsorbed on SiO ₂ /Ag/MIPs with different thicknesses. From the figure, we can see that the SERS intensity of SiO ₂ /Ag/MIPs with a polymer layer thickness of 40nm (a) is the highest, followed by 100nm (b), and the lowest at 170nm (c);

Figure 4: SERS spectra (a) of SiO ₂ /Ag/MIPs adsorbed with different concentrations of R6G and the linear relationship between Raman intensity and R6G concentration (b). From the figure, we can see that at 1505cm ^-1 , as the concentration of R6G gradually decreases, the Raman intensity decreases, and the relationship between the two is a function;

Fig. 5: SERS spectral selective detection of SiO ₂ /Ag/MIPs in 10 ^–6 mol/L R6G(a), RB(b) and CV(c). We can see from the figure that the peak value of R6G is larger than that of RB and CV.

In the specific embodiment of the present invention, the detection ability evaluation is carried out according to the following method: all the SERS substrates adsorbed with different concentrations of R6G are dropped on the glass slides and air-dried naturally. Excitation 633nm, each sample spectrum was collected with an exposure time of 10s and an incident laser power of 0.25mW, SERS spectra were collected using a 50× Nikon lens. The concentration [c] of R6G is used as the abscissa, and the SERS intensity is used as the ordinate to draw the curve.

Test example 1:

Firstly, the Raman intensity of different concentration of R6G adsorbed on SiO ₂ /Ag/MIPs was detected, and then the linear relationship between Raman intensity and R6G concentration was investigated. Prepare 10 ^-6 -10 ^-14 mol/L R6G solution, divide 10 mg SiO ₂ /Ag/MIPs into the centrifuge tube five times, add different concentrations of R6G for adsorption, and drop the substrate on the carrier after the adsorption is completed. The slides were air-dried, placed under the objective lens, adjusted the objective lens, and then detected the Raman intensity of the solution. It can be observed at 1505cm ^-1 that the Raman intensity decreases as the concentration of R6G gradually decreases, and the two are in a function relationship.

Test example 2:

The selectivity of SiO ₂ /Ag/MIPs to R6G, RB and CV was investigated (as shown in Figure 5, the prepared SiO ₂ /Ag/MIPs had a higher selectivity to R6G at a concentration of 10 ^-6 mol/L Strong, also selective to RB and CV but weaker than that). Make R6G, RB and CV into a 10 ^-6 mol/L solution. Take 10mL R6G, RB, CV solution and 10mg SiO ₂ /Ag/MIPs respectively into the centrifuge tube for adsorption, after the adsorption is completed, drop the substrate on the glass slide, let it dry naturally, put it under the objective lens, adjust the objective lens, The Raman intensity of the solution is then detected. The Raman curve will be drawn with the wavelength as the abscissa and the relative Raman intensity as the ordinate. The results showed that SiO ₂ /Ag/MIPs had good selectivity to R6G.

Claims (7)

1. A high-performance and highly controllable core-shell imprinted sensor, characterized in that the sensor is composed of amino-functionalized silica, Ag, and imprinted layers, and the Ag is loaded on amino-functionalized SiO ₂ /Ag nanocomposite particles are formed on silicon dioxide; the imprinted layer is polymerized from acrylamide, ethylene glycol dimethacrylate and azobisisobutyronitrile, and the imprinted layer is coated on Except for the functionalized SiO ₂ /Ag nanocomposite particles, the imprinted layer has a thickness of 40-170 nm. 2. A method for preparing a high-performance and highly controllable core-shell type imprinted sensor as claimed in claim 1, wherein the steps are as follows: Step 1, preparation of amino-functionalized silica nanoparticles Add ammonia water to the ethanol/water mixed solution, under stirring conditions, add TEOS, stir A, then add APTES, continue stirring reaction; centrifuge the product, wash and dry to obtain amino-functionalized silica nanoparticles, ready to use; Step 2. Preparation of functionalized SiO ₂ /Ag nanocomposite particles Disperse amino-functionalized silica nanoparticles in ethanol/water mixed solution, add silver nitrate solution and PVP solution, and stir magnetically in a dark environment; then, add EA, raise the temperature and continue stirring reaction; centrifuge the solid product, Washing and drying to obtain functionalized SiO ₂ /Ag nanocomposite particles, ready for use; Step 3. Preparation of core-shell SiO ₂ /Ag/MIPs Disperse the functionalized SiO ₂ /Ag nanocomposite particles into acetonitrile, add rhodamine 6G, AM and EGDMA, and remove oxygen with inert gas; then, add AIBN, seal, place in a constant temperature water bath shaker, set at 50°C Carry out a prepolymerization reaction, then raise the temperature to 60°C to continue the reaction; the solid product is centrifuged, washed, and dried to obtain core-shell SiO ₂ /Ag/MIPs, that is, the high-performance and highly controllable core-shell imprinted sensor. 3. the preparation method of high performance and highly controllable core-shell type imprinted sensor as claimed in claim 2 is characterized in that, in step 1, the volume ratio of described ethanol/water mixed solution, ammoniacal liquor, TEOS, APTES is 80～100:10～20:9:1～3; in the ethanol/water mixed solution, the volume ratio of ethanol and water is 4:5; the time of stirring A is 4～6h, and the continuous stirring reaction The time is 10 ~ 14h. 4. The preparation method of high-performance and highly controllable core-shell type imprinted sensor as claimed in claim 2, is characterized in that, in step 2, described amino-functionalized silicon dioxide nanoparticle, ethanol/water mixed solution, The dosage ratio of silver nitrate solution, PVP solution and EA is 100mg: 50mL: 5mL: 4～6mL: 0.4～0.6mL; the concentration of the silver nitrate solution is 0.1mol/L, and the concentration of the PVP solution is 0.2mol/L L, in the ethanol/water mixed solution, the volume ratio of ethanol to water is 4:1; the time for magnetic stirring in a dark environment is 4-6 hours, and the time for continuing stirring is 3-5 hours. 5. The preparation method of high performance and highly controllable core-shell type imprinted sensor as claimed in claim 2, is characterized in that, in step 3, described functionalized SiO ₂ /Ag nanocomposite particles, acetonitrile, rhodamine 6G , AM, EGDMA, AIBN dosage ratio is 100mg: 50-70mL: 0.05-0.15mmol: 0.3-0.5mmol: 0.237-0.396mL: 9-11mg; the inert gas is nitrogen. 6. The method for preparing a high-performance and highly controllable core-shell imprinted sensor according to claim 2, characterized in that, in steps 1-3, the washings are performed three times with ethanol and water respectively. 7. The application of the high-performance and highly controllable core-shell type imprinted sensor of claim 1 for selectively adsorbing rhodamine 6G.