CN113185979A - Preparation method and application of fluorescent sensor based on F-PDA molecular imprinting ratio - Google Patents

Preparation method and application of fluorescent sensor based on F-PDA molecular imprinting ratio Download PDF

Info

Publication number
CN113185979A
CN113185979A CN202110434395.6A CN202110434395A CN113185979A CN 113185979 A CN113185979 A CN 113185979A CN 202110434395 A CN202110434395 A CN 202110434395A CN 113185979 A CN113185979 A CN 113185979A
Authority
CN
China
Prior art keywords
pda
sio
ratio
cdte qds
preparation
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
CN202110434395.6A
Other languages
Chinese (zh)
Other versions
CN113185979B (en
Inventor
徐叶青
马明树
彭龙
黄婷
闫永胜
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Jiangsu University
Original Assignee
Jiangsu University
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Jiangsu University filed Critical Jiangsu University
Priority to CN202110434395.6A priority Critical patent/CN113185979B/en
Publication of CN113185979A publication Critical patent/CN113185979A/en
Application granted granted Critical
Publication of CN113185979B publication Critical patent/CN113185979B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
    • C09K11/00—Luminescent, e.g. electroluminescent, chemiluminescent materials
    • C09K11/08—Luminescent, e.g. electroluminescent, chemiluminescent materials containing inorganic luminescent materials
    • C09K11/88—Luminescent, e.g. electroluminescent, chemiluminescent materials containing inorganic luminescent materials containing selenium, tellurium or unspecified chalcogen elements
    • C09K11/881—Chalcogenides
    • C09K11/883—Chalcogenides with zinc or cadmium
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
    • C08F283/00—Macromolecular compounds obtained by polymerising monomers on to polymers provided for in subclass C08G
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
    • C08F292/00—Macromolecular compounds obtained by polymerising monomers on to inorganic materials
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
    • C09K11/00—Luminescent, e.g. electroluminescent, chemiluminescent materials
    • C09K11/02—Use of particular materials as binders, particle coatings or suspension media therefor
    • C09K11/025—Use of particular materials as binders, particle coatings or suspension media therefor non-luminescent particle coatings or suspension media
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
    • C09K11/00—Luminescent, e.g. electroluminescent, chemiluminescent materials
    • C09K11/06—Luminescent, e.g. electroluminescent, chemiluminescent materials containing organic luminescent materials

Abstract

The invention belongs to the technical field of novel nano material preparation, and discloses a preparation method and application of a fluorescent sensor based on F-PDA molecular imprinting ratio. The invention prepares the organic fluorescent nano material F-PDA by a simple method, then prepares the silicon-coated cadmium telluride quantum dot by a reverse microemulsion method, and finally prepares the F-PDA molecular imprinting ratio fluorescent sensor by a precipitation polymerization method, thereby establishing a synthetic method with simple operation and low environmental pollution. In addition, F-PDA is used as a fluorescent functional monomer to participate in polymerization, so that the response time of a target object is shortened, and the prepared F-PDA molecular imprinting ratio fluorescent sensor has a series of advantages of simple preparation method, low cost, strong stability, good optical performance and the like, can be used for identifying and detecting p-nitrophenol with high sensitivity and high selectivity, and realizes qualitative, quantitative and visual detection of the p-nitrophenol in the environmental water body.

Description

Preparation method and application of fluorescent sensor based on F-PDA molecular imprinting ratio
Technical Field
The invention belongs to the field of novel nano material preparation, and relates to a preparation method and application of a fluorescent sensor based on F-PDA molecular imprinting ratio.
Background
P-Nitrophenol (P-Nitrophenol, P-NP for short) is an important raw material in chemical industry, is also an important intermediate in the production of chemical products, and is widely applied to the fields of medicine manufacture, dye manufacture, leather preservative, pesticide intermediates and the like. As one of main pollutants in industrial wastewater, p-nitrophenol has many hazards such as high toxicity, high pathogenicity, weak biodegradability and the like, and the ingestion of low-concentration p-nitrophenol can cause great hazards to the health of human bodies, such as headache, fever, blood vessels, musculoskeletal injuries, liver and kidney injuries and the like. Therefore, the content determination of p-nitrophenol is very urgent for both human health and environmental protection. In recent years, research on a method for detecting nitrophenol has received much attention. Common detection methods for p-nitrophenol include ultraviolet-visible spectrophotometry, fluorescence, electrochemistry, capillary electrophoresis, High Performance Liquid Chromatography (HPLC), and the like.
In recent years, fluorescent polydopamine (F-PDA) has attracted extensive attention of researchers in various countries as a new organic fluorescent nano material. Compared with the common quantum dots, the F-PDA has a series of significant advantages of no toxicity, stable luminous performance, simple preparation, good biocompatibility and the like, and has been widely researched in the fields of energy, environment, biosensing and the like. In addition, the surface of the F-PDA contains active functional groups such as amino and hydroxyl which are beneficial to imprinting polymerization. Therefore, the F-PDA can be used as a fluorescent monomer and a blotting functional monomer at the same time, so that the F-PDA can be uniformly distributed in the synthesized fluorescent blotting material, and the defect that the fluorescence performance of the traditional fluorescent monomer is reduced due to embedding can be avoided. However, the actual size of the F-PDA is nano-scale, a large amount of cross-linking agents are used in the traditional imprinting process, the free radical polymerization process is not controllable, and the F-PDA is bound to be embedded. Therefore, the method for controlling the size of the fluorescent imprinting material by controllable polymerization while introducing the F-PDA as a fluorescent monomer and a functional monomer is still of great significance for determining the fluorescent property of the fluorescent imprinting material.
Molecularly Imprinted Polymers (MIPs) have been paid attention to by researchers because of their characteristics such as structure-activity presettability, simple preparation method, good stability, high efficiency selectivity, and practicality, and are widely used in many fields such as solid-phase extraction, catalysis, membrane separation, and sensors. The molecularly imprinted fluorescent sensor combines a fluorescent sensor with a molecularly imprinted technology, so that the molecularly imprinted fluorescent sensor has the advantages of high sensitivity of the fluorescent sensor and high selectivity of a molecularly imprinted polymer, and the application range of the sensor is expanded.
In the invention, F-PDA is used as a fluorescent matrix, and a molecular imprinting ratio fluorescent sensor prepared by combining a molecular imprinting technology is used for detecting p-nitrophenol.
Disclosure of Invention
The invention aims to overcome the technical defects in the prior art, such as: the process for detecting the p-nitrophenol is complex and time-consuming in operation, long in pretreatment time, poor in method stability, expensive and precise in instrument and the like. The invention uses F-PDA as fluorescent substrate, and utilizes molecular imprinting technology to prepare fluorescent sensor (CdTe QDs @ SiO) based on F-PDA molecular imprinting ratio2@ F-PDA @ MIPs), the fluorescence sensor has the advantages of simple preparation method, low cost, strong stability, good optical performance and the like, can be used for identifying and detecting p-nitrophenol with high sensitivity and high selectivity, and realizes qualitative, quantitative and visual detection of p-nitrophenol.
Specifically, the invention is carried out according to the following technical scheme:
a preparation method of a fluorescent sensor based on F-PDA molecular imprinting ratio comprises the following steps:
(1) preparing an organic fluorescent nano material F-PDA:
dissolving a certain amount of dopamine DA hydrochloride and polyethyleneimine PEI in deionized water, ultrasonically dispersing uniformly, and standing for a period of time; finally, adjusting the pH value with dilute hydrochloric acid, filtering, freeze-drying, and adding a proper amount of deionized water for dissolving to obtain an F-PDA solution for later use;
(2) preparation of cadmium telluride quantum dot silicon-coated CdTe QDs @ SiO2：
Adding cyclohexane, n-hexanol and triton X-100 into a flask, magnetically stirring at room temperature, adding cadmium telluride quantum solution, magnetically stirring, and adding H2O and ammonia water, then carrying out magnetic stirring, dropwise adding TEOS, carrying out magnetic stirring reaction under the dark condition, demulsifying by using acetone with the same volume as the total volume of cyclohexane, n-hexanol and Triton X-100 after the reaction is finished, washing by using ethanol, and drying to obtain CdTe QDs @ SiO2And is ready for use;
(3) cadmium telluride quantum dot silicon-coated CdTe QDs @ SiO2Connecting double bonds:
adding toluene into a flask, and then adding CdTe QDs @ SiO2Dispersing the mixture evenly, finally adding gamma-methacryloxypropyltrimethoxysilane KH570 into the mixture to perform oil bath reaction to obtain a product CdTe QDs @ SiO2Washing KH570 with ethanol for several times, and oven drying;
(4) fluorescent sensor CdTe QDs @ SiO based on F-PDA molecular imprinting ratio2Preparation of @ F-PDA @ MIPs:
adding CdTe QDs @ SiO into a flask2The preparation method comprises the following steps of (1) carrying out magnetic stirring on KH570, ethanol and F-PDA uniformly, adding P-NP, ethylene glycol dimethacrylate EGDMA and azobisisobutyronitrile AIBN, introducing nitrogen for a period of time, carrying out water bath reaction, after the reaction is finished, alternately washing with ethanol and water, drying, and finally obtaining the F-PDA molecular imprinting ratio fluorescence sensor.
In the step (1), the dosage ratio of DA, PEI and deionized water is 100 mg: 0.1 mL: 20 mL; the standing time is 3.0h, the concentration of dilute hydrochloric acid is 1.0M, and the pH value is adjusted to 7.0; in the obtained F-PDA solution, the dosage ratio of F-PDA to deionized water is 20 mg: 3.0 mL.
In the step (2), the dosage ratio of the cyclohexane to the hexanol to the triton X-100 is 7.5 mL: 1.8 mL: 1.77 mL; said H2The dosage ratio of O, ammonia water and TEOS is respectively 200-600 mu L: 120-360 mu L: 50-150 mu L, wherein the dosage ratio of the cyclohexane to the CdTe QDs to the TEOS is 7.5 mL: 1.0-5.0 mL: 50-150 μ L.
In the step (2), the rotation speed of the magnetic stirring is 800rpm/min, the magnetic stirring time is 30min after the CdTe QDs and the ammonia water are added, and the magnetic stirring time is 24h after the TEOS is added.
In the step (3), the toluene and the CdTe QDs @ SiO2And KH570 in a 50mL ratio: 100 mg: 1.5 mL; the temperature of the oil bath reaction is 90 ℃, and the reaction time is 24 h.
In the step (4), the step (c),
the CdTe QDs @ SiO2The dosage ratio of the KH570 to the ethanol to the F-PDA is 50-150 mg: 60mL of: 2.5-7.5 mL;
the dosage ratio of the P-NP, the EGDMA and the AIBN is 13.9 mg: 66-198 μ L: 5-15 mg;
CdTe QDs@SiO2the dosage ratio of-KH 570 to P-NP is 50-150 mg: 13.9 mg.
In the step (4), the rotating speed of the magnetic stirring is 800rpm/min, the stirring time is 30min, and N is introduced2The time of (2) is 20 min; the water bath reaction process comprises the following steps: the reaction is carried out for 6.0h at 50 ℃, and the reaction is carried out for 12-36 h after the temperature is raised to 60 ℃.
According to the F-PDA molecular imprinting ratio fluorescence sensor prepared by the invention, F-PDA is used as a fluorescence functional monomer to participate in polymerization, and the F-PDA quantum dots are uniformly dispersed, have no agglomeration phenomenon and have high fluorescence efficiency.
The F-PDA molecular imprinting ratio fluorescence sensor prepared by the invention is used for detecting p-nitrophenol in water.
The beneficial effects of the invention are as follows:
(1) the organic fluorescent nano material F-PDA prepared by the invention has the advantages of uniform dispersion, no agglomeration and excellent fluorescent effect, and takes the F-PDA as a fluorescent functional monomer to participate in polymerization, so that the response time of a target object is shortened; meanwhile, the organic fluorescent nano material prepared by the method can be used for preparing a molecular imprinting ratio fluorescent sensor based on F-PDA. Compared with a complex preparation method, the preparation method is simpler, more convenient and safer, has low raw material cost, reduces the waste of other resources, and can be used for quickly identifying the p-nitrophenol.
(2) In the case of nitro compounds, the electron-withdrawing property is so large that electrons that have been transferred to an excited state can be pulled to a group, so that the probability of electron transfer from the excited state to the ground state is reduced, and the appearance is shown as a weak fluorescence emission. The addition of p-nitrophenol would result in fluorescence quenching for the F-PDA ratio fluorescence sensor. And fitting a linear relation through the difference of fluorescence quenching degrees of the fluorescent sensor based on the F-PDA molecular imprinting ratio of the p-nitrophenol with different concentrations, thereby realizing the quantitative detection of the p-nitrophenol. Meanwhile, the recognition effect of the imprinted fluorescent sensor and a p-nitrophenol analog is explored, and the best quenching effect of p-nitrophenol on the molecularly imprinted fluorescent sensor is found, so that the F-PDA-based molecularly imprinted ratiometric fluorescent sensor prepared by the method can be used for carrying out visualization and quantitative detection and analysis on the p-nitrophenol in a sample with high sensitivity and high selectivity.
Drawings
FIG. 1 is a confocal laser microscopy (LSCM) of the F-PDA ratio fluorescence based fluorescence sensor of the present invention;
FIG. 2 is a mapping chart of the F-PDA based molecular imprinting ratio fluorescence sensor of the present invention;
FIG. 3 is a graph showing the relative fluorescence intensity of the F-PDA ratio-based fluorescence sensor of the present invention after mixing with different concentrations of p-nitrophenol;
FIG. 4 is a linear relationship diagram of the relative fluorescence intensity of the F-PDA ratio-based fluorescence sensor of the present invention after mixing with p-nitrophenol at different concentrations;
FIG. 5 is a graph showing the selectivity of the F-PDA based fluorescence sensor for p-nitrophenol and its analogues at the same concentration.
Detailed Description
The invention is further illustrated by the following examples.
DA, PEI, ammonia, TEOS, n-hexanol, Triton X-100, KH-570, P-NP, EGDMA and AIBN used in the present invention were analytically pure and purchased from Shanghai Allantin reagents, Inc. Cyclohexane, acetone, toluene and ethanol were purchased from the national pharmaceutical group chemical agents limited and deionized water from the university of Jiangsu laboratory.
Example 1:
(1) preparing organic fluorescent nano material (F-PDA):
dissolving 100mg of dopamine hydrochloride and 0.1mL of polyethyleneimine in 20mL of deionized water, ultrasonically dispersing uniformly, and standing at room temperature for 3.0 h; and finally, adjusting the pH value to 7.0 by using 1.0M dilute hydrochloric acid, filtering, freeze-drying, and adding 3.0mL of deionized water for dissolving to obtain an F-PDA solution for later use.
(2) Preparation of cadmium telluride Quantum dot silicon-coated (CdTe QDs @ SiO)2)：
Adding 7.5mL of cyclohexane, 1.8mL of hexanol and 1.77mL of triton X-100 into a 25mL flask, magnetically stirring at 800rpm/min at room temperature, adding 1.0mL of cadmium telluride quantum solution, stirring for 30min, and adding 200 mu L H2O and 120. mu.L of ammonia water, and stirring for 30 min. 50 μ L TEOS was added dropwise and reacted for 24h in the dark. After the reaction is finished, acetone with the same volume as that of cyclohexane, hexanol and triton X-100 is used for demulsification, and the mixture is washed by ethanol and dried for later use. (3) Cadmium telluride quantum dot silicon-coated (CdTe QDs @ SiO)2) Connecting double bonds:
50mL of toluene was added to a 100mL flask, and 100mg of CdTe QDs @ SiO was added2The mixture was dispersed uniformly, and 1.5mL of gamma-methacryloxypropyltrimethoxysilane (KH-570) was added to the mixture, followed by oil bath reaction at 90 ℃ for 24 hours. Washing the obtained product with ethanol for many times, and drying for later use.
(4) Fluorescent sensor (CdTe QDs @ SiO) based on F-PDA molecular imprinting ratio2@ F-PDA @ MIPs):
50mg of CdTe QDs @ SiO is added into a 100mL flask2KH570, 60mL ethanol, 2.5mL F-PDA was added and magnetically stirred at 800rpm/min for 30 min. 13.9mg of P-NP, 66. mu.L of Ethylene Glycol Dimethacrylate (EGDMA), 5mg of Azobisisobutyronitrile (AIBN) were added thereto, and nitrogen was passed through for 20 min. After the nitrogen introduction is finished, water bath reaction is carried out, reaction is carried out for 6h at 50 ℃, and reaction is carried out for 12h at 60 ℃. And after the reaction is finished, alternately washing with ethanol and water, and drying for later use.
Example 2:
(1) preparing organic fluorescent nano material (F-PDA):
dissolving 100mg of dopamine hydrochloride and 0.1mL of polyethyleneimine in 20mL of deionized water, ultrasonically dispersing uniformly, and standing at room temperature for 3.0 h; and finally, adjusting the pH value to 7.0 by using 1.0M dilute hydrochloric acid, filtering, freeze-drying, and adding 3.0mL of deionized water for dissolving to obtain an F-PDA solution for later use.
(2) Preparation of cadmium telluride Quantum dot silicon-coated (CdTe QDs @ SiO)2)：
Adding 7.5mL of cyclohexane, 1.8mL of hexanol and 1.77mL of triton X-100 into a 25mL flask, magnetically stirring at 800rpm/min at room temperature, adding 1.0mL of cadmium telluride quantum solution, stirring for 30min, and adding 400 mu L H2O and 240. mu.L of ammonia water, and stirred for 30 min. 100 μ L TEOS was added dropwise and reacted for 24h in the dark. After the reaction is finished, acetone with the same volume as that of cyclohexane, hexanol and triton X-100 is used for demulsification, and the mixture is washed by ethanol and dried for later use.
(3) Cadmium telluride quantum dot silicon-coated (CdTe QDs @ SiO)2) Connecting double bonds:
50mL of toluene was added to a 100mL flask, and 100mg of CdTe QDs @ SiO was added2The mixture was dispersed uniformly, and 1.5mL of gamma-methacryloxypropyltrimethoxysilane (KH-570) was added to the mixture, followed by oil bath reaction at 90 ℃ for 24 hours. Washing the obtained product with ethanol for many times, and drying for later use.
(4) Fluorescent sensor (CdTe QDs @ SiO) based on F-PDA molecular imprinting ratio2@ F-PDA @ MIPs):
100mg of CdTe QDs @ SiO is added into a 100mL flask2KH570, 60mL ethanol, 5.0mL F-PDA was added and magnetically stirred at 800rpm/min for 30 min. 13.9mg of P-NP, 132. mu.L of Ethylene Glycol Dimethacrylate (EGDMA), 10mg of Azobisisobutyronitrile (AIBN) were added and nitrogen was passed through for 20 min. After the nitrogen introduction is finished, water bath reaction is carried out, the reaction lasts for 6 hours at 50 ℃ and 24 hours at 60 ℃. And after the reaction is finished, alternately washing with ethanol and water, and drying for later use.
FIG. 1 is a confocal laser microscope of the fluorescence sensor based on the F-PDA molecular imprinting ratio2 is mapping diagram of ratio fluorescence sensor, and CdTe QDs @ SiO can be seen from the diagram2The @ F-PDA @ MIPs has good polymerization effect and high fluorescence efficiency.
Example 3:
(1) preparing organic fluorescent nano material (F-PDA):
dissolving 100mg of dopamine hydrochloride and 0.1mL of polyethyleneimine in 20mL of deionized water, ultrasonically dispersing uniformly, and standing at room temperature for 3.0 h; and finally, adjusting the pH value to 7.0 by using 1.0M dilute hydrochloric acid, filtering, freeze-drying, and adding 3.0mL of deionized water for dissolving to obtain an F-PDA solution for later use.
(2) Preparation of cadmium telluride Quantum dot silicon-coated (CdTe QDs @ SiO)2)：
Adding 7.5mL of cyclohexane, 1.8mL of hexanol and 1.77mL of triton X-100 into a 25mL flask, magnetically stirring at 800rpm/min at room temperature, adding 1.0mL of cadmium telluride quantum solution, stirring for 30min, and adding 600 mu L H2O and 360 mu L ammonia water, and stirring for 30 min. 150 μ L TEOS was added dropwise and reacted for 24h in the dark. After the reaction is finished, acetone with the same volume as that of cyclohexane, hexanol and triton X-100 is used for demulsification, and the mixture is washed by ethanol and dried for later use.
(3) Cadmium telluride quantum dot silicon-coated (CdTe QDs @ SiO)2) Connecting double bonds:
50mL of toluene was added to a 100mL flask, and 100mg of CdTe QDs @ SiO was added2The mixture was dispersed uniformly, and 1.5mL of gamma-methacryloxypropyltrimethoxysilane (KH-570) was added to the mixture, followed by oil bath reaction at 90 ℃ for 24 hours. Washing the obtained product with ethanol for many times, and drying for later use.
(4) Fluorescent sensor (CdTe QDs @ SiO) based on F-PDA molecular imprinting ratio2@ F-PDA @ MIPs):
150mg of CdTe QDs @ SiO is added into a 100mL flask2KH570, 60mL ethanol, 7.5mL F-PDA was added and magnetically stirred at 800rpm/min for 30 min. 13.9mg of P-NP, 198. mu.L of Ethylene Glycol Dimethacrylate (EGDMA), 15mg of Azobisisobutyronitrile (AIBN) were added and nitrogen was passed through for 20 min. After the nitrogen introduction is finished, water bath reaction is carried out, the reaction lasts for 6 hours at 50 ℃ and for 36 hours at 60 ℃. And after the reaction is finished, alternately washing with ethanol and water, and drying for later use.
Detection of p-nitrophenol by a fluorescent sensor based on F-PDA molecular imprinting ratio:
test example 1:
preparing p-nitrophenol aqueous solutions with different concentrations (0 nM, 100nM, 200nM, 300nM, 400nM, 500nM, 600nM, 700nM, 800nM, 900nM, 1000nM respectively), weighing 1.39mg of p-nitrophenol, adding 100mL of deionized water to prepare a p-nitrophenol aqueous solution, adding 50 μ L of molecularly imprinted polymer dispersion and 10 μ L of p-nitrophenol solution into a 10mL colorimetric tube, adding deionized water to a constant volume of 10mL, oscillating at room temperature, and standing for 3.0 min. Under the conditions that the excitation wavelength of 360nm, the slit width of the excitation wavelength and the slit width of the emission wavelength are both 10nm, the voltage of a photomultiplier is 800V, and the scanning wavelength range is 450-750nm, a fluorescence spectrophotometer is used for researching the influence of p-nitrophenol with different concentrations on the fluorescence intensity of the molecularly imprinted polymer with the same concentration.
FIG. 3 is a graph showing the effect of the fluorescence sensor with different concentrations of p-nitrophenol in the present invention, wherein each line represents the fluorescence intensity curve of the fluorescence sensor with the concentration of 0nM, 100nM, 200nM, 300nM, 400nM, 500nM, 600nM, 700nM, 800nM, 900nM, 1000nM p-nitrophenol solution and the molecular imprinting ratio fluorescence sensor from top to bottom. It can be visually seen from the figure that the fluorescence intensity of the molecularly imprinted ratiometric fluorescent sensor gradually decreases with the increase of the concentration of the p-nitrophenol solution, which indicates that the molecularly imprinted ratiometric fluorescent sensor can qualitatively detect the p-nitrophenol.
FIG. 4 is a linear graph of the relative fluorescence intensity of the fluorescence sensor of the present invention mixed with p-nitrophenol solution of different concentration, as can be seen from FIG. 4, with p-nitrophenol concentration [ c ]]Is the abscissa, log [ (I)652/I533)/(I652/I533)0]A fluorescence response curve is plotted for the ordinate, yielding the corresponding equation: log [ (I)652/I533)/(I652/I533)0]＝0.0000971CP-NP0.08318, linear range 0-1000 nM. The results show that F-PDA based molecular imprinting ratio fluorescence sensingThe method for detecting p-nitrophenol is simple, does not need complex sample pretreatment, has high sensitivity and has good optical detection capability.
Test example 2:
target (P-nitrophenol, P-NP) and its analogues (catechol, O-NP, cellulose acetate, CA, 2, 4-dichlorophenol, 2,4-DP) were prepared into 0.1mM aqueous solutions, and mixed by sonication. Taking 50 mu L of imprinted polymer CdTe QDs @ SiO2Adding the @ F-PDA @ MIPs dispersion liquid into a 10mL colorimetric tube, adding 10 mu L of p-nitrophenol or the aqueous solution of the p-nitrophenol or the analogue thereof, fixing the volume to 10mL by using deionized water, respectively oscillating the mixed solution at room temperature, standing for 3.0min, and respectively recording the fluorescence intensity of the mixed solution before and after the p-nitrophenol or the analogue thereof is added by using a fluorescence spectrophotometer.
FIG. 5 shows the imprinted polymer CdTe QDs @ SiO of the present invention2A graph of relative fluorescence intensity of @ F-PDA @ MIPs versus nitrophenol and analogs thereof at the same concentration; as can be seen from the figure, the relative fluorescence intensity value log [ (I) of the F-PDA-based molecularly imprinted fluorescence sensor before and after the addition of the p-nitrophenol652/I533)/(I652/I533)0]The linear amplitude has a large variation range, and the relative fluorescence intensity values log [ (I) before and after adding O-NP, CA and 2,6-DP respectively652/I533)/(I652/I533)0]The linear amplitude variation range is small. The detection result shows that the quenching quantity of p-nitrophenol to the fluorescent sensor based on the F-PDA molecular imprinting ratio is the largest and is obviously higher than that of p-nitrophenol analogues, which indicates that the fluorescent sensor based on the F-PDA molecular imprinting ratio has obvious specific recognition effect on p-nitrophenol.

Claims (10)

1. A preparation method of a fluorescent sensor based on F-PDA molecular imprinting ratio is characterized by comprising the following steps:
(1) preparing an organic fluorescent nano material F-PDA:
dissolving a certain amount of dopamine DA hydrochloride and polyethyleneimine PEI in deionized water, ultrasonically dispersing uniformly, and standing for a period of time; finally, adjusting the pH value with dilute hydrochloric acid, filtering, freeze-drying, and adding a proper amount of deionized water for dissolving to obtain an F-PDA solution for later use;
(2) preparation of cadmium telluride quantum dot silicon-coated CdTe QDs @ SiO2：
Adding cyclohexane, n-hexanol and triton X-100 into a flask, magnetically stirring at room temperature, adding cadmium telluride quantum solution, magnetically stirring, and adding H2O and ammonia water, then carrying out magnetic stirring, dropwise adding TEOS, carrying out magnetic stirring reaction under the dark condition, demulsifying by using acetone with the same volume as the total volume of cyclohexane, n-hexanol and Triton X-100 after the reaction is finished, washing by using ethanol, and drying to obtain CdTe QDs @ SiO2And is ready for use;
(3) cadmium telluride quantum dot silicon-coated CdTe QDs @ SiO2Connecting double bonds:
adding toluene into a flask, and then adding CdTe QDs @ SiO2Dispersing the mixture evenly, finally adding gamma-methacryloxypropyltrimethoxysilane KH570 into the mixture to perform oil bath reaction to obtain a product CdTe QDs @ SiO2Washing KH570 with ethanol for several times, and oven drying;
(4) fluorescent sensor CdTe QDs @ SiO based on F-PDA molecular imprinting ratio2Preparation of @ F-PDA @ MIPs:
adding CdTe QDs @ SiO into a flask2The preparation method comprises the following steps of (1) carrying out magnetic stirring on KH570, ethanol and F-PDA uniformly, adding P-NP, ethylene glycol dimethacrylate EGDMA and azobisisobutyronitrile AIBN, introducing nitrogen for a period of time, carrying out water bath reaction, after the reaction is finished, alternately washing with ethanol and water, drying, and finally obtaining the F-PDA molecular imprinting ratio fluorescence sensor.
2. The production method according to claim 1, wherein, in the step (1),
the dosage ratio of DA, PEI and deionized water is 100 mg: 0.1 mL: 20 mL; the standing time is 3.0h, the concentration of dilute hydrochloric acid is 1.0M, and the pH value is adjusted to 7.0;
in the obtained F-PDA solution, the dosage ratio of F-PDA to deionized water is 20 mg: 3.0 mL.
3. The production method according to claim 1, wherein, in the step (2),
the dosage ratio of the cyclohexane to the hexanol to the triton X-100 is 7.5 mL: 1.8 mL: 1.77 mL;
said H2The dosage ratio of O, ammonia water and TEOS is respectively 200-600 mu L: 120-360 mu L: 50 to 150 mu L of the composition,
the dosage proportion of the cyclohexane, the CdTe QDs and the TEOS is 7.5 mL: 1.0-5.0 mL: 50-150 μ L.
4. The method according to claim 1, wherein in the step (2), the rotation speed of the magnetic stirring is 800rpm/min, the time of the magnetic stirring is 30min after the CdTe QDs and the ammonia water are added, and the time of the magnetic stirring is 24h after the TEOS is added.
5. The production method according to claim 1, wherein, in the step (3),
the toluene and the CdTe QDs @ SiO2And KH570 in a 50mL ratio: 100 mg: 1.5 mL;
the temperature of the oil bath reaction is 90 ℃, and the reaction time is 24 h.
6. The production method according to claim 1, wherein, in the step (4),
the CdTe QDs @ SiO2The dosage ratio of the KH570 to the ethanol to the F-PDA is 50-150 mg: 60mL of: 2.5-7.5 mL;
the dosage ratio of the P-NP, the EGDMA and the AIBN is 13.9 mg: 66-198 μ L: 5-15 mg;
CdTe QDs@SiO2the dosage ratio of-KH 570 to P-NP is 50-150 mg: 13.9 mg.
7. The method according to claim 1, wherein in the step (4), the rotation speed of the magnetic stirring is 800rpm/min, the stirring time is 30min, and N is introduced2The time of (2) is 20 min.
8. The preparation method according to claim 1, wherein in the step (4), the water bath reaction is carried out by: the reaction is carried out for 6.0h at 50 ℃, and the reaction is carried out for 12-36 h after the temperature is raised to 60 ℃.
9. A fluorescence sensor based on F-PDA molecular imprinting ratio is characterized in that the fluorescence sensor is prepared by the preparation method of any one of claims 1-8, F-PDA is used as a fluorescence functional monomer to participate in polymerization, and F-PDA quantum dots are uniformly dispersed.
10. Use of the F-PDA based molecular imprinting ratio fluorescence sensor of claim 9 for detecting p-nitrophenol in a body of water.
CN202110434395.6A 2021-04-22 2021-04-22 Preparation method and application of fluorescent sensor based on F-PDA molecular imprinting ratio Active CN113185979B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202110434395.6A CN113185979B (en) 2021-04-22 2021-04-22 Preparation method and application of fluorescent sensor based on F-PDA molecular imprinting ratio

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202110434395.6A CN113185979B (en) 2021-04-22 2021-04-22 Preparation method and application of fluorescent sensor based on F-PDA molecular imprinting ratio

Publications (2)

Publication Number Publication Date
CN113185979A true CN113185979A (en) 2021-07-30
CN113185979B CN113185979B (en) 2022-04-26

Family

ID=76978070

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202110434395.6A Active CN113185979B (en) 2021-04-22 2021-04-22 Preparation method and application of fluorescent sensor based on F-PDA molecular imprinting ratio

Country Status (1)

Country Link
CN (1) CN113185979B (en)

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105466898A (en) * 2015-11-30 2016-04-06 江苏大学 Preparation method of amino CQD (carbon quantum dot) fluorescence and 4-nitrophenol molecularly imprinted sensor
CN112300335A (en) * 2020-09-30 2021-02-02 江苏大学 Preparation method and application of molecular imprinting sensor based on F-PDA (Fabry-Perot digital Assistant)

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105466898A (en) * 2015-11-30 2016-04-06 江苏大学 Preparation method of amino CQD (carbon quantum dot) fluorescence and 4-nitrophenol molecularly imprinted sensor
CN112300335A (en) * 2020-09-30 2021-02-02 江苏大学 Preparation method and application of molecular imprinting sensor based on F-PDA (Fabry-Perot digital Assistant)

Also Published As

Publication number Publication date
CN113185979B (en) 2022-04-26

Similar Documents

Publication Publication Date Title
Gui et al. Ratiometric fluorescent sensor with molecularly imprinted mesoporous microspheres for malachite green detection
Li et al. Molecularly imprinted silica nanospheres embedded CdSe quantum dots for highly selective and sensitive optosensing of pyrethroids
Zhao et al. Composite QDs@ MIP nanospheres for specific recognition and direct fluorescent quantification of pesticides in aqueous media
Liu et al. Fabrication of carbon dots@ restricted access molecularly imprinted polymers for selective detection of metronidazole in serum
Feng et al. Surface molecular imprinting on dye–(NH2)–SiO2 NPs for specific recognition and direct fluorescent quantification of perfluorooctane sulfonate
CN111171806B (en) Preparation method and application of molecular imprinting ratio type fluorescent probe based on up-conversion nano material
CN110243889B (en) Based on CsPbBr3Molecular imprinting photoelectrochemical sensor with/GO (graphene oxide) homotype heterostructure as well as preparation method and application thereof
CN108485661B (en) Preparation method and application of fluorescent carbon quantum dots
Sun et al. Chiral colorimetric recognition of amino acids based on silver nanoparticle clusters
Wu et al. TiO2 nanoparticles-enhanced luminol chemiluminescence and its analytical applications in organophosphate pesticide imprinting
CN103937486B (en) A kind of fluorescent nano probe and its preparation method and application
Wei et al. Molecularly imprinted polymer nanospheres based on Mn-doped ZnS QDs via precipitation polymerization for room-temperature phosphorescence probing of 2, 6-dichlorophenol
Wei et al. A novel molecularly imprinted polymer thin film at surface of ZnO nanorods for selective fluorescence detection of para-nitrophenol
CN104479072A (en) Method for preparing magnetic molecularly-imprinted adsorbent
JP2005062178A (en) Microencapsulation of oxygen sensing particle
CN101726476B (en) Fluorescence probe for detecting thio-modified biomoleculesa, preparation and application methods thereof
Huo et al. Photo-luminescent chiral carbon-dot@ Eu (D-cam) nanocomposites for selectively luminescence sensing of L-phenylalanine
Zhou et al. A mesoporous fluorescent sensor based on ZnO nanorods for the fluorescent detection and selective recognition of tetracycline
CN113201336A (en) Preparation method based on nitrogen-phosphorus doped carbon quantum dots and application of preparation method in rapid detection of tartrazine
CN111534299B (en) GOQDs@PDA-ir-MIP molecularly imprinted fluorescent sensor and preparation method and application thereof
Wei et al. Molecularly imprinted CsPbBr 3 quantum dot-based fluorescent sensor for trace tetracycline detection in aqueous environments
Lulka et al. Molecular imprinting of small molecules with organic silanes: fluorescence detection
Yang et al. Molecularly imprinted polymers-isolated AuNP-enhanced CdTe QD fluorescence sensor for selective and sensitive oxytetracycline detection in real water samples
CN112300335B (en) Preparation method and application of molecular imprinting sensor based on F-PDA (Fabry-Perot digital Assistant)
CN113185979B (en) Preparation method and application of fluorescent sensor based on F-PDA molecular imprinting ratio

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant