CN110776916B - Quantum dot dual-emission-ratio fluorescent probe and preparation method and application thereof - Google Patents

Quantum dot dual-emission-ratio fluorescent probe and preparation method and application thereof Download PDF

Info

Publication number
CN110776916B
CN110776916B CN201910892730.XA CN201910892730A CN110776916B CN 110776916 B CN110776916 B CN 110776916B CN 201910892730 A CN201910892730 A CN 201910892730A CN 110776916 B CN110776916 B CN 110776916B
Authority
CN
China
Prior art keywords
quantum dot
water
ethanol
fluorescent probe
dual
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.)
Active
Application number
CN201910892730.XA
Other languages
Chinese (zh)
Other versions
CN110776916A (en
Inventor
汪晶
刘馨月
黄亮
胡军
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.)
Zhejiang University of Technology ZJUT
Original Assignee
Zhejiang University of Technology ZJUT
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 Zhejiang University of Technology ZJUT filed Critical Zhejiang University of Technology ZJUT
Priority to CN201910892730.XA priority Critical patent/CN110776916B/en
Publication of CN110776916A publication Critical patent/CN110776916A/en
Application granted granted Critical
Publication of CN110776916B publication Critical patent/CN110776916B/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
    • 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
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
    • G01N21/62—Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light
    • G01N21/63—Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light optically excited
    • G01N21/64—Fluorescence; Phosphorescence
    • G01N21/6428—Measuring fluorescence of fluorescent products of reactions or of fluorochrome labelled reactive substances, e.g. measuring quenching effects, using measuring "optrodes"
    • G01N21/643—Measuring fluorescence of fluorescent products of reactions or of fluorochrome labelled reactive substances, e.g. measuring quenching effects, using measuring "optrodes" non-biological material
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
    • G01N21/62—Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light
    • G01N21/63—Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light optically excited
    • G01N21/64—Fluorescence; Phosphorescence
    • G01N21/6447—Fluorescence; Phosphorescence by visual observation

Landscapes

  • Chemical & Material Sciences (AREA)
  • Health & Medical Sciences (AREA)
  • Immunology (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • General Physics & Mathematics (AREA)
  • Organic Chemistry (AREA)
  • Nuclear Medicine, Radiotherapy & Molecular Imaging (AREA)
  • Analytical Chemistry (AREA)
  • Biochemistry (AREA)
  • General Health & Medical Sciences (AREA)
  • Materials Engineering (AREA)
  • Pathology (AREA)
  • Inorganic Chemistry (AREA)
  • Molecular Biology (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Optics & Photonics (AREA)
  • Investigating, Analyzing Materials By Fluorescence Or Luminescence (AREA)
  • Luminescent Compositions (AREA)

Abstract

The invention relates to the technical field of ratiometric fluorescent probes, and provides a quantum dot dual-emission-ratio fluorescent probe, as well as a preparation method and application thereof, aiming at solving the problem of poor fluorescence ratio regulation accuracy of the traditional quantum dot ratiometric fluorescent probe. The quantum dot dual-emission ratio fluorescent probe has the advantages of uniform particle size, adjustable fluorescence ratio and stable performance; the preparation method is simple and efficient, the quantum dots are directly assembled in the organic phase, the surface of the quantum dots is not required to be modified and decorated, the assembly efficiency is high, the complex and tedious pretreatment such as phase transfer of the quantum dots is avoided, and the maintenance of the quantum yield is facilitated.

Description

Quantum dot dual-emission-ratio fluorescent probe and preparation method and application thereof
Technical Field
The invention relates to the technical field of ratiometric fluorescent probes, in particular to a quantum dot dual-emission ratiometric fluorescent probe and a preparation method and application thereof.
Background
Ratiometric fluorescent probes are a new type of fluorescent sensor that has attracted considerable attention in recent years, which combine two different fluorophores in a nanoparticle, one fluorophore being the reference and the other fluorophore being the signal element, and detect the analyte by measuring the change in the ratio of the fluorescence intensities at the two wavelengths. Compared with single-wavelength measurement, the ratiometric fluorescence technology is not influenced by external environments such as light source intensity and instrument sensitivity, can provide internal built-in correction for environmental effects, and has the advantages of improving sensitivity and accuracy.
Quantum dots and organic dyes are commonly used as fluorescent signals for ratiometric probes. Compared with organic dyes, the quantum dots have the advantages of high fluorescence quantum yield, photobleaching resistance, narrow and symmetrical emission spectrum, wide absorption spectrum, wavelength tunability and the like. Because the synthesis method of the aqueous phase quantum dots is simple, the fluorescent probe prepared by the aqueous phase quantum dots can be directly applied to aqueous solution, and the aqueous phase quantum dots are commonly used for preparing the ratiometric fluorescent microspheres. However, the water-soluble quantum dots have low fluorescence yield and unstable properties, and are limited in application. The quantum dots with high luminescence property, good monodispersity and high color purity are usually synthesized in oil phase. The surface of the quantum dot synthesized in the oil phase is coated with a layer of organic ligand molecules, so that the quantum dot has stable property and hydrophobicity. However, the biocompatibility of the quantum dots can be effectively improved by assembling the oil-soluble quantum dots and the nano-carrier.
The silica spheres have higher optical transparency, controllable size and simple synthesis method, can be subjected to various surface silanization modifications, and are excellent nano carriers. The mesoporous silica spheres have the advantages of large specific surface area, high thermal stability and the like, so that the mesoporous silica spheres are widely applied. The existing quantum dot fluorescence ratio microsphere preparation technology mainly loads quantum dots in silicon spheres or on the surfaces of the silicon spheres through embedding or covalent coupling. For example, tetraethyl silicate is hydrolyzed to form a silicon layer, water-soluble quantum dots are embedded in the silicon layer in a water phase to form fluorescent microspheres, amino modification is carried out on the surface of the silicon microspheres, carboxyl of the water-soluble quantum dots is activated by carbodiimide, and then the carboxyl is loaded on the surface of the fluorescent microspheres through amido bonds to obtain the ratiometric fluorescent microspheres. Or adding some emulsifying agents, mixing the quantum dots and the carbon dots according to a certain proportion, and embedding the two fluorescent substances in the silicon spheres by utilizing the hydrolysis of the tetraethyl silicate to form the fluorescent microspheres.
In the method, the quantum dots need to be modified to a certain extent, so that the ligand on the surface of the quantum dots can fall off in the assembling process, the fluorescence quenching is caused, the loading efficiency is low, and the fluorescence intensity ratio of the finally obtained microsphere has randomness.
Chinese patent literature discloses a construction method and application of a dual-emission-ratio fluorescent probe, wherein the publication number is CN106350069A, the invention prepares the dual-emission fluorescent probe by modifying BPEI-CQDs carbon quantum dots on a silicon dioxide ball, the dual-emission fluorescent probe has high stability under severe conditions, and the established method for measuring the content of the dual-emission fluorescent probe in human urineAnd trace Cu in blood plasma2+The method has the advantages of good selectivity, high sensitivity and visualization. However, the double-emission-ratio fluorescent probe adopts an embedding method to take red CdTe/CdS water-phase quantum dots as the inner core of the fluorescent silicon spheres, in the preparation process, the surface ligands of the quantum dots are easy to change to cause the fluorescence to weaken, and meanwhile, as can be seen from a transmission electron microscope image, the loading capacity of the red quantum dots in each fluorescent silicon sphere is small; the probe has good stability under the condition of pH 5-7, and the fluorescence is weakened under other pH conditions, so that the probe has the problems of unstable property and limited application conditions.
Disclosure of Invention
The invention provides a quantum dot dual-emission-ratio fluorescent probe with uniform particle size, adjustable fluorescence ratio and stable performance, aiming at overcoming the problems of poor regulation and control accuracy of the fluorescence ratio, insufficient stability of water-soluble quantum dot and limited application in organisms of the traditional quantum dot ratio fluorescent probe.
The invention provides a preparation method of a quantum dot dual-emission-ratio fluorescent probe, which aims to overcome the problems that a quantum dot needs to be modified to a certain extent in the preparation process of the traditional quantum dot-ratio fluorescent probe, a ligand on the surface of the quantum dot possibly falls off in the assembly process, so that fluorescence quenching is caused, the loading efficiency is low, and the fluorescence intensity ratio of a finally obtained microsphere has randomness.
The invention also provides application of the quantum dot dual-emission-ratio fluorescent probe in visual detection of melamine.
In order to achieve the purpose, the invention adopts the following technical scheme:
a quantum dot dual-emission-ratio fluorescent probe takes a green quantum dot as a core, is embedded in a sulfhydrylated mesoporous silica sphere, is subjected to silanization and sulfhydrylation treatment, is added with a red quantum dot, and is subjected to ultrasonic assembly and silanization treatment to obtain the quantum dot dual-emission-ratio fluorescent probe; the green quantum dots are oil-phase CdSe/ZnS quantum dots (G-QDs) emitting green fluorescence; the red quantum dots are red fluorescent oil phase CdSe/ZnS quantum dots (R-QDs).
The quantum dot dual-emission ratio fluorescent probe directly loads the oil-soluble quantum dots with relatively stable properties into the sulfhydrylation mesoporous silica spheres by utilizing the metal-ligand affinity effect, thereby realizing the high-efficiency assembly of the quantum dots; after silanization and sulfydryl modification are carried out on the composite microspheres, quantum dots with another wavelength are loaded, and the addition amount of the quantum dots is controlled, so that the fluorescent probes with different ratios, uniform particle size, adjustable fluorescence ratio and stable performance are obtained. The green quantum dot and the red quantum dot are based on CdSe/ZnS quantum dots which have the same element composition and emit two fluorescent colors, the principle is that the quantum dots have size dependence, the size of the quantum dots is increased along with the prolonging of reaction time, and emitted light can be adjusted from blue to red. The green quantum dots are oil-phase CdSe/ZnS quantum dots emitting green fluorescence, and the size of the quantum dots is 8 nm; the red quantum dots are red fluorescence-emitting oil-phase CdSe/ZnS quantum dots, the size of the red fluorescence-emitting oil-phase CdSe/ZnS quantum dots is 12nm, and the ratio and the color of the quantum dot dual-emission ratio fluorescent probe can be adjusted by adjusting the adding amount of the red quantum dots and the green quantum dots, so that the quantum dot dual-emission ratio fluorescent probes with different fluorescence intensity ratios can be obtained.
A preparation method of a quantum dot dual-emission ratio fluorescent probe comprises the following steps:
(1) adding a chloroform solution of green quantum dots into sulfhydrylation mesoporous silica spheres, carrying out ultrasonic treatment, centrifuging to obtain precipitate (SQ), adding octyl trimethoxy silane (OTMS) after the chloroform is volatilized from the precipitate, uniformly mixing, transferring to a methanol/ammonia water mixed solution, reacting, centrifuging to obtain precipitate, washing, dispersing in a water/ammonia water mixed solution, uniformly stirring, centrifuging to obtain water-soluble silica/green quantum dot fluorescent microspheres (marked as OTMS-dSiO)2@ QDs, OTMS-SQ, abbreviated as OTMS-SQ), S represents mesoporous silica spheres, dendritic silica supports (dSiO)2) (ii) a Q represents Quantum dots, Quantum Dots (QDs), SQ is dSiO2For the abbreviation of @ QDs, OTMS-SQ being after transfer of the aqueous phaseHydrophilic green fluorescent microspheres; the method comprises the following steps of directly realizing high-density loading of oil-soluble quantum dots in an organic phase by taking sulfhydrylation mesoporous silica spheres as a metal affinity template; the silanization modification, namely the hydrophilic modification, of the quantum dot assembly is realized through the hydrolytic condensation of an alkyl silanization reagent (OTMS), the phase transfer of the quantum dot microspheres is realized, the reduction of the quantum dot light efficiency caused by a conventional ligand replacement method is effectively avoided, the high light-emitting efficiency is kept, and then the controllable growth of a silicon dioxide shell layer is further carried out;
(2) Dispersing the water-soluble silicon dioxide/green quantum dot fluorescent microspheres obtained in the step (1) in an ethanol/water mixed solution, adding ammonia water and Tetraethoxysilane (TEOS), uniformly stirring, and centrifuging to obtain silanized silicon dioxide/green quantum dot fluorescent microspheres (marked as dSiO)2@QDs@SiO2And, abbreviated as SQS); the first S represents mesoporous silica spheres (dSiO)2) (ii) a The second S represents the coated silica shell (denoted SQS); in the step, tetraethoxysilane is added to fill the pores of the mesoporous silica spheres, provide an attachment space for red quantum dots and separate the red quantum dots from the green quantum dots;
(3) dispersing the silanized silica/green quantum dot fluorescent microspheres obtained in the step (2) in ethanol, adding ammonia water and (3-mercaptopropyl) trimethoxysilane (MPTMS), uniformly stirring, centrifuging to obtain precipitates, washing the precipitates, and uniformly dispersing the precipitates in the ethanol to obtain sulfhydrylated silica/green quantum dot fluorescent microsphere dispersion liquid (marked as dSiO)2@QDs@SiO2-SH, abbreviated SQS-SH);
(4) centrifuging the sulfhydrylated silicon dioxide/green quantum dot fluorescent microsphere dispersion liquid obtained in the step (3), adding a chloroform solution of red quantum dots into the precipitate, performing ultrasonic treatment, and centrifuging; adding octyl trimethoxy silane (OTMS) into the precipitate (SQSQSQSQSQSQ), mixing uniformly, transferring to methanol/ammonia water mixed solution, reacting, centrifuging to obtain precipitate, washing the precipitate, dispersing in the water/ammonia water mixed solution, stirring uniformly, centrifuging, dispersing in ethanol to obtain water-soluble silicon dioxide/green quantum dot/silicon dioxide/red quantum dot fluorescent microsphere (marked as OTMS-dSiO2@QDs@SiO2@ QDs, abbreviated OTMS-SQSQSQSQSQSQSQSQ);
(5) dispersing the water-soluble silicon dioxide/green quantum dot/silicon dioxide/red quantum dot fluorescent microspheres obtained in the step (4) in an ethanol solution, adding water, ammonia water and Tetraethoxysilane (TEOS), stirring at room temperature, centrifugally collecting products, washing, and dispersing in water to obtain silicon dioxide/green quantum dot/silicon dioxide/red quantum dot/silicon dioxide composite fluorescent microspheres (marked as dSiO2@QDs@SiO2@QDs@SiO2And abbreviated as SQSQS), namely the quantum dot dual emission ratio fluorescent probe.
The existing quantum dot ratio fluorescent microspheres are usually prepared by embedding or co-building coupling of water phase quantum dots, but a ligand on the surface of the water phase quantum dots is easily damaged in the modification process, the final fluorescence intensity is possibly influenced, and the fluorescence ratio cannot be accurately regulated. When the fluorescent signal molecules are loaded on the surface of the silicon sphere and exposed in a solution, the analyte cannot be determined to quench the fluorescent signal molecules, and the quantum dots contain toxic metal ions, so that the application of the fluorescent signal molecules to organisms is limited.
According to the preparation method of the quantum dot dual-emission-ratio fluorescent probe, the mesoporous silica spheres with the metal affinity surfaces (such as thiol modification) and the oil-soluble quantum dots are directly assembled in the organic phase, so that the assembly efficiency is high, the complex and tedious pretreatment such as quantum dot phase transfer is avoided, and the maintenance of the quantum yield is facilitated. Meanwhile, as the oil-soluble quantum dots are stable in property, the ratio and the color of the quantum dot dual-emission ratio fluorescent probe can be adjusted by controlling the amount of the quantum dots with two colors in the process of preparing the ratio probe, so that the quantum dot dual-emission ratio fluorescent probes with different fluorescence intensity ratios can be obtained.
Preferably, in the step (1), the thiolated mesoporous silica spheres are prepared according to the following method: adding ammonia water and (3-mercaptopropyl) trimethoxysilane into an ethanol solution of the mesoporous silica spheres, stirring overnight at room temperature, centrifuging to collect a product, and washing with ethanol to obtain the sulfhydrylated mesoporous silica spheres.
Preferably, the mesoporous silica spheres are prepared by the following method: adding cetyl trimethyl ammonium bromide and sodium salicylate into triethanolamine aqueous solution at the temperature of 75-85 ℃, continuously stirring, adding tetraethyl silicate, continuously reacting, centrifugally collecting a product, washing the product for several times by using ethanol to remove residual reactants, extracting the collected product by using a hydrochloric acid/methanol mixed solution at the temperature of 55-65 ℃ to remove a template, centrifugally collecting the product, and washing to obtain the mesoporous silica spheres.
Preferably, in the step (1), the mass ratio of the green quantum dots to the sulfhydrylated mesoporous silica spheres is (0.4-0.6): 1.
preferably, in the step (1) and the step (4), the volume ratio of ammonia water to methanol in the methanol/ammonia water mixed solution is (0.02-0.03): 1.
preferably, in the step (1) and the step (4), the volume ratio of the aqueous ammonia to the water in the aqueous ammonia/aqueous ammonia mixed solution is (2 × 10) -3～2.4×10-3)：1。
Preferably, in the step (2), the volume ratio of ethanol to water in the ethanol/water mixed solution is (3-4.5): 1.
preferably, in the step (4), the mass ratio of the red quantum dots to the thiolated silica/green quantum dots fluorescent microspheres is (0.04-0.06) based on the total mass of the thiolated silica/green quantum dots/silica fluorescent microspheres: 1.
preferably, in the step (5), the volume ratio of ethanol to water is (3-4.5): 1; the volume ratio of the ammonia water to the total amount of the ethanol and the water is (0.02-0.03): 1; the volume ratio of TEOS to the total amount of ethanol and water is (0.002-0.003): 1.
The application of the quantum dot dual-emission-ratio fluorescent probe in visual detection of melamine is characterized in that rapid visual detection of melamine is performed through an internal filtering effect of gold nanoparticles (AuNPs) and the quantum dot dual-emission-ratio fluorescent probe.
Preferably, the method for visually detecting the melamine based on the quantum dot dual-emission ratio fluorescent probe comprises the following steps:
synthesizing aqueous phase AuNPs with the particle size of about 13nm by a sodium citrate reduction method. The method is characterized in that melamine is added into a solution containing AuNPs, the amine group of the melamine interacts with citrate on the surface of the AuNPs through ligand exchange and hydrogen bonds, so that the AuNPs are changed from a monodisperse state to an aggregated state, the ultraviolet spectrum is changed, and after a fluorescent probe is added, an absorption signal is converted into a fluorescent signal for detecting the melamine through fluorescence and visualization.
Although many methods for detecting melamine have been reported, simple, rapid and efficient detection is still the focus of research. Gold nanoparticles (AuNPs) are widely used due to their unique size-dependent optical properties and the accompanying color change of the solution. The Internal Filter Effect (IFE) refers to the absorption of excitation or emission light of a fluorophore by an absorbent agent in a detection system. In contrast to traditional fluorescence methods based on fluorescence resonance energy transfer, IFE does not require chemical linkage between the absorber and the fluorophore. AuNPs have high molar extinction coefficients and are good absorbers, so the IFE of AuNPs to quantum dots is considered to be an effective strategy for developing fluorescence methods.
Therefore, the invention has the following beneficial effects:
(1) the quantum dot dual-emission ratio fluorescent probe has the advantages of uniform particle size, adjustable fluorescence ratio and stable performance;
(2) the preparation method is simple and efficient, the quantum dots are directly assembled in the organic phase, the surfaces of the quantum dots are not required to be modified, the assembly efficiency is high, the complex and tedious pretreatment such as phase transfer of the quantum dots is avoided, and the maintenance of the quantum yield is facilitated;
(3) the quantum dot dual-emission ratio fluorescent probe can realize rapid visual detection of melamine with gold nanoparticles (AuNPs) based on Internal Filtering Effect (IFE), and compared with the traditional fluorescence method based on fluorescence resonance energy transfer, the IFE does not need chemical connection between an absorbent and a fluorophore, and has wider application range.
Drawings
FIG. 1 is a schematic diagram of the synthetic mechanism of the preparation method of the quantum dot dual-emission ratio fluorescent probe of the invention.
FIG. 2 shows mesoporous silica prepared in example 1Ball dSiO2A TEM image of (a).
FIG. 3 is a TEM image of silica/green quantum dot fluorescent microspheres (OTMS-SQ) prepared in example 1.
FIG. 4 is a TEM image of silica/green quantum dot/silica fluorescent microspheres (SQS) prepared in example 1.
FIG. 5 is a TEM image of silica/green quantum dot/silica/red quantum dot fluorescent microspheres (SQSQSQSQSQ) prepared in example 1.
FIG. 6 is a TEM image of silica/green quantum dot/silica/red quantum dot/silica composite fluorescent microsphere (SQSQSQS) prepared in example 1.
FIG. 7 is a fluorescent photograph of SQSQS obtained in example 1 after adding different concentrations of melamine when detecting melamine in water.
FIG. 8 is a fluorescence spectrum of SQSQSQS obtained in example 1 after different concentrations of melamine were added when detecting melamine in water.
FIG. 9 shows the results of the detection of melamine in water by SQSQSQS obtained in example 1, I627/I528Linear plot with melamine concentration (0.02-0.96 μ M) (n-3).
FIG. 10 is a linear calibration chart of the hue value as a function of melamine when SQSQSQS prepared in example 2 is used for detecting melamine in milk. The inset is a fluorescent photograph and calculated concentrations (by hue value) of nanoprobes with different amounts of added melamine.
Detailed Description
The technical solution of the present invention is further specifically described below by using specific embodiments and with reference to the accompanying drawings.
In the present invention, all the equipment and materials are commercially available or commonly used in the art, and the methods in the following examples are conventional in the art unless otherwise specified.
In the following examples of the present invention, CdSe/ZnS green quantum dots (G-QDs) were purchased from Guangdong Pujiafu opto-electronic technology, Inc., and manufactured under the production lot number 180409T 2501103; CdSe/ZnS red quantum dots (R-QDs) were purchased from Guangdong Pujiafu opto-electronic technology, Inc. under the production lot number ZS 027.
The following examples of the invention:
the synthesis method of the mesoporous silica spheres comprises the following steps:
0.14g Triethanolamine (TEA) was added to 50ml water and magnetically stirred in an oil bath at 80 ℃ for 0.5 hour. Then, 0.76g of cetyltrimethylammonium bromide (CTAB) and 0.34g of sodium salicylate (NaSal) were added to the above solution and stirring was continued for 1 hour. Then, 8ml of tetraethyl silicate (TEOS) was added to the water-CTAB-NaSal-TEA solution with stirring for 4 hours. The product was collected by centrifugation and washed several times with ethanol to remove residual reactants. Extracting the collected product twice with hydrochloric acid and methanol solution at 60 ℃ for 6 hours to remove the template, collecting the product by centrifugation and washing with ethanol for several times, and finally dispersing the product in the ethanol solution to obtain the mesoporous silica spheres.
The synthetic method of the sulfhydrylation mesoporous silica spheres comprises the following steps:
and (3) adding 0.7mL of ammonia water and 0.5mL of (3-mercaptopropyl) trimethoxysilane (MPTMS) into 100mL of the ethanol solution of the mesoporous silica spheres, stirring at room temperature overnight, centrifuging to collect the product of the sulfhydrylated mesoporous silica spheres, washing with ethanol for three times, finally storing the product in the ethanol solution, and storing in a refrigerator at 4 ℃ for later use.
The synthesis method of the gold nanoparticles (AuNPs) comprises the following steps:
1mM HAuCl4heating 150mL of aqueous solution to boiling under reflux and stirring, quickly adding 15mL of 1% trisodium citrate, continuously heating for 20min until the solution turns into wine red, cooling to room temperature, filtering with a 0.22 μm filter head, and storing at 4 deg.C for later use.
Example 1
(1) Taking 1mL of sulfhydrylation mesoporous silica sphere ethanol solution for centrifugation, adding 10mg mL of precipitation-10.5mL of chloroform solution of CdSe/ZnS green quantum dots, and carrying out ultrasonic treatment to obtain a green homogeneous solution; centrifuging to obtain a silicon dioxide/green quantum dot compound precipitate (SQ); slightly drying the silicon dioxide/quantum dot microsphere precipitate in the air, adding 100 mu L OTMS, and dissolving the precipitate to obtain a homogeneous solution; the solution was transferred to a mixed solution of 7.5mL of methanol and 187.5. mu.L of aqueous ammonia and reacted for 30min; the precipitate was centrifuged and washed once with methanol. Dispersing the precipitate in 16.5mL of water, adding 33 mu L of ammonia water, and stirring at room temperature overnight to obtain water-soluble silicon dioxide/quantum dot fluorescent microspheres (OTMS-SQ);
(2) And (2) dispersing the water-soluble silicon dioxide/green quantum dot fluorescent microspheres obtained in the step (1) in 30mL of water-ethanol mixed solution, adding 0.75mL of ammonia water and 300 mu L of TEOS, and stirring at room temperature for 10 hours. Centrifuging the solution, washing the solution for 3 times by using ethanol, and dispersing the precipitate in 10mL of ethanol to obtain silanized silicon dioxide/green quantum dot fluorescent microspheres (SQS);
(3) dispersing the silanized silica/green quantum dot fluorescent microspheres obtained in the step (2) in ethanol, adding 30mL of ethanol and 1mL of ammonia water into the 10mL of ethanol dispersion, uniformly mixing, adding 200 mu L of MPTMS, stirring overnight at room temperature, centrifuging, and washing with ethanol for three times to obtain sulfhydrylated silica/green quantum dot fluorescent microsphere dispersion (SQS-SH);
(4) centrifuging the sulfhydrylated silicon dioxide/green quantum dot fluorescent microsphere dispersion liquid obtained in the step (3), and adding 2mg mL of precipitation-11mL of chloroform solution of CdSe/ZnS red quantum dots, and ultrasonically treating to obtain homogeneous red transparent solution; centrifuging to obtain silicon dioxide/red quantum dot composite precipitate (SQSQSQSQSQ), adding 100 μ L OTMS into the precipitate, dissolving the precipitate to obtain homogeneous solution, adding 7.5mL methanol and 187.5 μ L ammonia water, and reacting for 30 min; centrifuge and wash the precipitate once with 7.5mL of methanol. Dispersing the precipitate in 16.5mL of water, adding 33 mu L of ammonia water, stirring at room temperature overnight, centrifuging, and dispersing the precipitate in 6mL of water to obtain water-soluble silica/green quantum dot/silica/red quantum dot fluorescent microspheres (OTMS-SQSQSQSQSQSQSQSQSQSQSQSQSQSQSQSQSQSQSQSQSQSQSQ);
(5) And (3) dispersing the water-soluble silicon dioxide/green quantum dot/silicon dioxide/red quantum dot fluorescent microspheres obtained in the step (4) in 24mL of ethanol solution, adding 6mL of water, 0.75mL of ammonia water and 60 muL of Tetraethoxysilane (TEOS), stirring at room temperature, centrifugally collecting products, washing, and dispersing in water to obtain silicon dioxide/green quantum dot/silicon dioxide/red quantum dot/silicon dioxide composite fluorescent microspheres (SQSQS), namely the quantum dot dual-emission-ratio fluorescent probe.
The quantum dot dual emission ratio fluorescent probe obtained in example 1 was applied to the detection of melamine in water, and the detection system was 1 mL. In a 2mL centrifuge tube, 5. mu.L ratiometric probe, 250. mu.L AuNPs, 50. mu.L melamine solutions at various concentrations were added, and PB (10mM pH 8.0) buffer was used to adjust the total volume to 1 mL. The fluorescence photograph was taken under a 365nm UV lamp, and the results are shown in FIG. 7: after adding different concentrations of melamine, the color of the solution changed from red to orange to green with increasing melamine concentration in the photograph under a 365nm ultraviolet lamp. The fluorescence spectrum is shown in FIG. 8: the spectrograms of the added melamine with different concentrations gradually increase the green fluorescence at 528nm and gradually decrease the red fluorescence at 627nm with the increase of the melamine concentration. FIG. 9 is a linear graph of the melamine concentration in water measured using the melamine concentration and the corresponding fluorescence intensity ratio as coordinates.
Example 2
Example 2 differs from example 1 in that the amount of red quantum dots added in step (4) of example 2 was 1.2mL (2.4mg), and the red-green fluorescence ratio of the resulting ratiometric probe was different from that of example 1.
The quantum dot dual-emission ratio fluorescent probe obtained in example 2 is applied to the detection of melamine in milk through a labeling recovery test, and the detection system is 1 mL. In a 2mL centrifuge tube, 5. mu.L of quantum dot dual emission ratio fluorescent probe, 250. mu.L of AuNPs, 50. mu.L of treated milk sample solution containing melamine at various concentrations were added, a total volume of 1mL was adjusted with PB (10mM pH 8.0) buffer, and fluorescence spectra were recorded. The fluorescence photograph was taken under a 365nm UV lamp, and the results are shown in FIG. 10: the inset is a fluorescence photograph of a detected milk sample, and the concentrations of melamine calculated from a chromaticity-concentration line chart are 0.201 μ M, 0.483 μ M and 0.779 μ M, respectively, and the sample solutions are orange, orange and yellow-green in color, respectively, and the concentrations are the detected concentrations.
Table 1 shows the results of the spectroscopic and visual detection of melamine in milk:
TABLE 1 detection of Melamine in milk
Figure BDA0002209275610000081
Data are expressed as mean ± standard deviation (n-3).
As can be seen from Table 1, the recovery rate of the labeled sample in the spectrum test is 101-108%, the recovery rate of the labeled sample in the visual test is 95-100%, and the relative standard deviation is small.
Example 3
Example 3 differs from example 1 in that the amount of red quantum dots added in step (4) of example 2 is 1.5mL (3.0mg), and the red-green fluorescence ratio of the resulting ratiometric probe differs from that of example 1.
Example 4
(1) Taking 1mL of sulfhydrylation mesoporous silica sphere ethanol solution for centrifugation, adding 10mg mL of precipitation-10.4mL of chloroform solution of CdSe/ZnS green quantum dots, and carrying out ultrasonic treatment to obtain a green homogeneous solution; centrifuging to obtain a silicon dioxide/green quantum dot compound precipitate (SQ); slightly drying the silicon dioxide/quantum dot microsphere precipitate in the air, adding 100 mu L OTMS, and dissolving the precipitate to obtain a homogeneous solution; transferring the solution into a mixed solution of 9mL of methanol and 180 mu L of ammonia water for reaction for 30 min; the precipitate was centrifuged and washed once with methanol. Dispersing the precipitate in 16.5mL of water, adding 33 mu L of ammonia water, and stirring at room temperature overnight to obtain water-soluble silicon dioxide/quantum dot fluorescent microspheres (OTMS-SQ);
(2) And (2) dispersing the water-soluble silicon dioxide/green quantum dot fluorescent microspheres obtained in the step (1) in a mixed solution of 6mL of water and 27mL of ethanol, adding 0.75mL of ammonia water and 300 mu L of TEOS, and stirring at room temperature for 10 hours. Centrifuging the solution, washing the solution with ethanol for 3 times, and dispersing the precipitate in 10mL of ethanol to obtain silanized silicon dioxide/green quantum dot fluorescent microspheres (SQS);
(3) dispersing the silanized silica/green quantum dot fluorescent microspheres obtained in the step (2) in ethanol, adding 30mL of ethanol and 1mL of ammonia water into the 10mL of ethanol dispersion, uniformly mixing, adding 200 mu L of MPTMS, stirring overnight at room temperature, centrifuging, and washing with ethanol for three times to obtain sulfhydrylated silica/green quantum dot fluorescent microsphere dispersion (SQS-SH);
(4) centrifuging the sulfhydrylated silica/green quantum dot fluorescent microsphere dispersion obtained in step (3), and adding 2mg mL of the solution to the precipitate (about 50.5mg)-11mL of chloroform solution of CdSe/ZnS red quantum dots, and ultrasonically treating to obtain homogeneous red transparent solution; centrifuging to obtain silicon dioxide/red quantum dot composite precipitate (SQSQSQSQ), adding 100 μ L OTMS into the precipitate, dissolving the precipitate to obtain homogeneous solution, adding 9mL methanol and 180 μ L ammonia water, and reacting for 30 min; centrifuge and wash the precipitate once with 7mL methanol. Dispersing the precipitate in 16.5mL of water, adding 33 mu L of ammonia water, stirring at room temperature overnight, centrifuging, and dispersing the precipitate in 6mL of water to obtain water-soluble silicon dioxide/green quantum dot/silicon dioxide/red quantum dot fluorescent microspheres (OTMS-SQSQSQSQSQSQSQSQSQSQSQSQ);
(5) And (3) dispersing the water-soluble silicon dioxide/green quantum dot/silicon dioxide/red quantum dot fluorescent microspheres obtained in the step (4) in 27mL of ethanol solution, adding 6mL of water, 1mL of ammonia water and 66 mu L of Tetraethoxysilane (TEOS), stirring at room temperature, centrifuging to collect products, washing, and dispersing in water to obtain silicon dioxide/green quantum dot/silicon dioxide/red quantum dot/silicon dioxide composite fluorescent microspheres (SQS), namely the quantum dot dual-emission ratio fluorescent probe.
Example 5
(1) Taking 1mL of sulfhydrylation mesoporous silica sphere ethanol solution for centrifugation, adding 10mg mL of precipitation-10.5mL of chloroform solution of CdSe/ZnS green quantum dots, and carrying out ultrasonic treatment to obtain a green homogeneous solution; centrifuging to obtain a silicon dioxide/green quantum dot compound precipitate (SQ); slightly drying the silicon dioxide/quantum dot microsphere precipitate in the air, adding 100 mu L OTMS, and dissolving the precipitate to obtain a homogeneous solution; transferring the solution into a mixed solution of 7mL of methanol and 210 mu L of ammonia water for reaction for 30 min; the precipitate was centrifuged and washed once with methanol. Dispersing the precipitate in 17mL of water, adding 40 mu L of ammonia water, and stirring overnight at room temperature to obtain water-soluble silicon dioxide/quantum dot fluorescent microspheres (OTMS-SQ);
(2) and (2) dispersing the water-soluble silicon dioxide/green quantum dot fluorescent microspheres obtained in the step (1) in a mixed solution of 7mL of water and 21mL of ethanol, adding 0.75mL of ammonia water and 300 mu L of TEOS, and stirring at room temperature for 10 hours. Centrifuging the solution, washing the solution with ethanol for 3 times, and dispersing the precipitate in 10mL of ethanol to obtain silanized silicon dioxide/green quantum dot fluorescent microspheres (SQS);
(3) Dispersing the silanized silica/green quantum dot fluorescent microspheres obtained in the step (2) in ethanol, adding 30mL of ethanol and 1mL of ammonia water into the 10mL of ethanol dispersion, uniformly mixing, adding 200 mu L of MPTMS, stirring overnight at room temperature, centrifuging, and washing with ethanol for three times to obtain sulfhydrylated silica/green quantum dot fluorescent microsphere dispersion (SQS-SH);
(4) centrifuging the sulfhydrylation silicon dioxide/green quantum dot fluorescent microsphere dispersion liquid obtained in the step (3), and adding 2mg mL into the precipitate (about 51.0mg)-11.2mL of chloroform solution of CdSe/ZnS red quantum dots, and ultrasonically treating to obtain homogeneous red transparent solution; centrifuging to obtain silicon dioxide/red quantum dot composite precipitate (SQSQSQSQ), adding 100 μ L OTMS into the precipitate, dissolving the precipitate to obtain homogeneous solution, adding 7mL methanol and 210 μ L ammonia water, and reacting for 30 min; centrifuge and wash the precipitate once with 7mL methanol. Dispersing the precipitate in 17mL of water, adding 40 mu L of ammonia water, stirring at room temperature overnight, centrifuging, and dispersing the precipitate in 6mL of water to obtain water-soluble silicon dioxide/green quantum dot/silicon dioxide/red quantum dot fluorescent microspheres (OTMS-SQSQSQSQSQSQSQSQSQSQSQSQSQSQSQSQ);
(5) and (3) dispersing the water-soluble silicon dioxide/green quantum dot/silicon dioxide/red quantum dot fluorescent microspheres obtained in the step (4) in 21mL of ethanol solution, adding 7mL of water, 0.66mL of ammonia water and 84 μ L of Tetraethoxysilane (TEOS), stirring at room temperature, centrifuging to collect products, washing, and dispersing in water to obtain silicon dioxide/green quantum dot/silicon dioxide/red quantum dot/silicon dioxide composite fluorescent microspheres (SQSQS), namely the quantum dot dual-emission-ratio fluorescent probe.
Example 6
(1) Taking 1mL of ethanol solution of the sulfhydrylation mesoporous silica spheres, centrifuging, adding 10mg mL of ethanol solution into the precipitate-10.6mL of chloroform solution of CdSe/ZnS green quantum dots, and carrying out ultrasonic treatment to obtain a green homogeneous solution; the mixture is centrifuged and then is subjected to centrifugal separation,obtaining a silicon dioxide/green quantum dot compound precipitate (SQ); slightly drying the silicon dioxide/quantum dot microsphere precipitate in the air, adding 100 mu L OTMS, and dissolving the precipitate to obtain a homogeneous solution; transferring the solution into a mixed solution of 7.5mL of methanol and 187.5 mu L of ammonia water for reaction for 30 min; the precipitate was centrifuged and washed once with methanol. Dispersing the precipitate in 16.8mL of water, adding 40 mu L of ammonia water, and stirring at room temperature overnight to obtain water-soluble silicon dioxide/quantum dot fluorescent microspheres (OTMS-SQ);
(2) and (2) dispersing the water-soluble silicon dioxide/green quantum dot fluorescent microspheres obtained in the step (1) in a mixed solution of 6.5mL of water and 26mL of ethanol, adding 0.75mL of ammonia water and 300 mu L of TEOS, and stirring at room temperature for 10 hours. Centrifuging the solution, washing the solution for 3 times by using ethanol, and dispersing the precipitate in 10mL of ethanol to obtain silanized silicon dioxide/green quantum dot fluorescent microspheres (SQS);
(3) dispersing the silanized silica/green quantum dot fluorescent microspheres obtained in the step (2) in ethanol, adding 30mL of ethanol and 1mL of ammonia water into the 10mL of ethanol dispersion, uniformly mixing, adding 200 mu L of MPTMS, stirring overnight at room temperature, centrifuging, and washing with ethanol for three times to obtain sulfhydrylated silica/green quantum dot fluorescent microsphere dispersion (SQS-SH);
(4) Centrifuging the sulfhydrylated silica/green quantum dot fluorescent microsphere dispersion obtained in step (3), and adding 2mg mL of the precipitate (about 51.6mg)-11.55mL of chloroform solution of CdSe/ZnS red quantum dots, and ultrasonically treating to obtain homogeneous red transparent solution; centrifuging to obtain silicon dioxide/red quantum dot composite precipitate (SQSQSQSQ), adding 100 μ L OTMS into the precipitate, dissolving the precipitate to obtain homogeneous solution, adding 7.5mL methanol and 187.5 μ L ammonia water, and reacting for 30 min; the precipitate was centrifuged and washed once with 7mL of methanol. Dispersing the precipitate in 16.8mL of water, adding 40 mu L of ammonia water, stirring at room temperature overnight, centrifuging, and dispersing the precipitate in 6mL of water to obtain water-soluble silica/green quantum dot/silica/red quantum dot fluorescent microspheres (OTMS-SQSQSQSQSQSQSQSQSQSQSQSQSQSQSQSQSQSQSQSQSQSQSQSQ);
(5) and (3) dispersing the water-soluble silicon dioxide/green quantum dot/silicon dioxide/red quantum dot fluorescent microspheres obtained in the step (4) in 26mL of ethanol solution, adding 6.5mL of water, 0.98mL of ammonia water and 65 muL of Tetraethoxysilane (TEOS), stirring at room temperature, centrifugally collecting products, washing, and dispersing in water to obtain silicon dioxide/green quantum dot/silicon dioxide/red quantum dot/silicon dioxide composite fluorescent microspheres (SQSQSQS), namely the quantum dot dual-emission ratio fluorescent probe.
The performance and application of the quantum dot dual emission ratio fluorescent probe prepared in examples 3-6 are equivalent to those of examples 1 and 2, and the description is omitted.
The above description is only a preferred embodiment of the present invention, and is not intended to limit the present invention in any way, and other variations and modifications may be made without departing from the spirit of the invention as set forth in the claims.

Claims (10)

1. A preparation method of a quantum dot dual-emission ratio fluorescent probe is characterized by comprising the following steps:
(1) adding a chloroform solution of green quantum dots into sulfhydrylated mesoporous silica spheres, performing ultrasonic treatment, centrifuging to obtain a precipitate, adding octyl trimethoxy silane after the chloroform is volatilized from the precipitate, uniformly mixing, transferring to a methanol/ammonia water mixed solution, centrifuging after reaction to obtain the precipitate, washing, dispersing in a water/ammonia water mixed solution, uniformly stirring, and centrifuging to obtain water-soluble silica/green quantum dot fluorescent microspheres;
(2) dispersing the water-soluble silicon dioxide/green quantum dot fluorescent microspheres obtained in the step (1) in an ethanol/water mixed solution, adding ammonia water and ethyl orthosilicate, uniformly stirring, and centrifuging to obtain silanized silicon dioxide/green quantum dot fluorescent microspheres;
(3) Dispersing the silanized silica/green quantum dot fluorescent microspheres obtained in the step (2) in ethanol, adding ammonia water and (3-mercaptopropyl) trimethoxysilane, uniformly stirring, centrifuging to obtain precipitates, washing the precipitates, and uniformly dispersing the precipitates in the ethanol to obtain sulfhydrylated silica/green quantum dot fluorescent microsphere dispersion liquid;
(4) centrifuging the sulfhydrylation silicon dioxide/green quantum dot fluorescent microsphere dispersion liquid obtained in the step (3), adding a chloroform solution of red quantum dots into the precipitate, performing ultrasonic treatment, and centrifuging; adding octyl trimethoxy silane into the precipitate, uniformly mixing, transferring the mixture into a methanol/ammonia water mixed solution, centrifuging after reaction to obtain precipitate, washing the precipitate, dispersing the washed precipitate into the water/ammonia water mixed solution, uniformly stirring, centrifuging, and dispersing in ethanol to obtain water-soluble silicon dioxide/green quantum dot/silicon dioxide/red quantum dot fluorescent microspheres;
(5) dispersing the water-soluble silicon dioxide/green quantum dot/silicon dioxide/red quantum dot fluorescent microspheres obtained in the step (4) in an ethanol solution, adding water, ammonia water and TEOS, stirring at room temperature, centrifugally collecting products, washing, and dispersing in water to obtain silicon dioxide/green quantum dot/silicon dioxide/red quantum dot/silicon dioxide composite fluorescent microspheres, namely the quantum dot dual-emission ratio fluorescent probe;
The green quantum dots are oil-phase CdSe/ZnS quantum dots emitting green fluorescence; the red quantum dots are red fluorescent oil phase CdSe/ZnS quantum dots.
2. The quantum dot dual emission ratio fluorescent probe prepared by the preparation method of the quantum dot dual emission ratio fluorescent probe according to claim 1, wherein the quantum dot dual emission ratio fluorescent probe takes a green quantum dot as a core, is embedded in a sulfhydrylated mesoporous silica sphere, and is subjected to silanization treatment, sulfhydrylation treatment, red quantum dot addition, ultrasonic assembly and silanization treatment to obtain the quantum dot dual emission ratio fluorescent probe.
3. The method for preparing a quantum dot dual-emission ratio fluorescent probe according to claim 1, wherein in the step (1), the thiolated mesoporous silica spheres are prepared according to the following method: adding ammonia water and (3-mercaptopropyl) trimethoxysilane into an ethanol solution of the mesoporous silica spheres, stirring overnight at room temperature, centrifuging to collect a product, and washing with ethanol to obtain the sulfhydrylated mesoporous silica spheres.
4. The method for preparing a quantum dot dual emission ratio fluorescent probe according to claim 1, wherein the mesoporous silica spheres are prepared by the following method: adding cetyl trimethyl ammonium bromide and sodium salicylate into triethanolamine aqueous solution at the temperature of 75-85 ℃, continuously stirring, adding tetraethyl silicate, continuously reacting, centrifugally collecting a product, washing the product for several times by using ethanol to remove residual reactants, extracting the collected product by using a hydrochloric acid/methanol mixed solution at the temperature of 55-65 ℃ to remove a template, centrifugally collecting the product, and washing to obtain the mesoporous silica spheres.
5. The method for preparing the quantum dot dual-emission ratio fluorescent probe according to claim 1, wherein in the step (1), the mass ratio of the green quantum dots to the sulfhydrylated mesoporous silica spheres is (0.4-0.6): 1.
6. the method for preparing the quantum dot dual-emission ratio fluorescent probe according to claim 1, wherein in the step (1) and the step (4), the volume ratio of ammonia water to methanol in the methanol/ammonia water mixed solution is (0.02-0.03): 1.
7. the method for preparing a quantum dot dual-emission ratio fluorescent probe according to claim 1, wherein in the step (2), the volume ratio of ethanol to water in the ethanol/water mixed solution is (3-4.5): 1.
8. the method for preparing the quantum dot dual-emission-ratio fluorescent probe according to claim 1, wherein in the step (4), the mass ratio of the red quantum dot to the thiolated silica/green quantum dot fluorescent microsphere is (0.04-0.06) based on the total mass of the thiolated silica/green quantum dot/silica fluorescent microsphere: 1.
9. the method for preparing the quantum dot dual-emission ratio fluorescent probe according to claim 1, wherein in the step (5), the volume ratio of ethanol to water is (3-4.5): 1; the volume ratio of the ammonia water to the total amount of the ethanol and the water is (0.02-0.03): 1; the volume ratio of TEOS to the total amount of ethanol and water is (0.002-0.003): 1.
10. The application method of the quantum dot dual-emission-ratio fluorescent probe in visual detection of melamine as claimed in claim 1, wherein rapid visual detection of melamine is performed by the internal filtering effect of the gold nanoparticles and the quantum dot dual-emission-ratio fluorescent probe.
CN201910892730.XA 2019-09-20 2019-09-20 Quantum dot dual-emission-ratio fluorescent probe and preparation method and application thereof Active CN110776916B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201910892730.XA CN110776916B (en) 2019-09-20 2019-09-20 Quantum dot dual-emission-ratio fluorescent probe and preparation method and application thereof

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201910892730.XA CN110776916B (en) 2019-09-20 2019-09-20 Quantum dot dual-emission-ratio fluorescent probe and preparation method and application thereof

Publications (2)

Publication Number Publication Date
CN110776916A CN110776916A (en) 2020-02-11
CN110776916B true CN110776916B (en) 2022-05-31

Family

ID=69384263

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201910892730.XA Active CN110776916B (en) 2019-09-20 2019-09-20 Quantum dot dual-emission-ratio fluorescent probe and preparation method and application thereof

Country Status (1)

Country Link
CN (1) CN110776916B (en)

Families Citing this family (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112557667B (en) * 2020-11-20 2022-05-17 浙江工业大学 C-reactive protein high-sensitivity immunoassay method based on double-color quantum dot ratio fluorescent probe
CN112326959A (en) * 2020-12-10 2021-02-05 南昌大学 Preparation and detection device of multicolor fluorescence signal opening type competitive immunochromatography test strip
CN113512319A (en) * 2021-06-22 2021-10-19 广东碳紫科技有限公司 Silicon dioxide coating additive with ultraviolet absorption function and preparation method thereof
CN115927553A (en) * 2021-08-20 2023-04-07 广州达安基因股份有限公司 Method and kit for constructing fluorescent oligonucleotide standard curve
CN115011345A (en) * 2022-06-30 2022-09-06 国纳纳米技术研究(河北)有限公司 Preparation method of bicolor quantum dot polystyrene microspheres
CN116515489B (en) * 2023-04-18 2024-04-26 浙江工业大学 Bicolor ratio fluorescent probe for visual rapid detection of trace water color identification in alcohol and application thereof
CN116836704A (en) * 2023-06-29 2023-10-03 苏州星烁纳米科技有限公司 Fluorescent microsphere and preparation method thereof
CN117089341A (en) * 2023-08-24 2023-11-21 齐鲁工业大学(山东省科学院) Preparation method and application of fluorescence sensor

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104910917A (en) * 2015-04-30 2015-09-16 浙江工业大学 Dual-color fluorescence quantum dot embedded ratiometric probe and preparation method thereof
CN107118763A (en) * 2017-05-19 2017-09-01 浙江工业大学 A kind of pair of emission ratios type fluorescence probe and its preparation and application

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104910917A (en) * 2015-04-30 2015-09-16 浙江工业大学 Dual-color fluorescence quantum dot embedded ratiometric probe and preparation method thereof
CN107118763A (en) * 2017-05-19 2017-09-01 浙江工业大学 A kind of pair of emission ratios type fluorescence probe and its preparation and application

Also Published As

Publication number Publication date
CN110776916A (en) 2020-02-11

Similar Documents

Publication Publication Date Title
CN110776916B (en) Quantum dot dual-emission-ratio fluorescent probe and preparation method and application thereof
CN110776915B (en) Fluorescent/colorimetric bifunctional microsphere based on multi-level assembly structure and preparation method thereof
Li et al. Synthesis of molecularly imprinted carbon dot grafted YVO4: Eu3+ for the ratiometric fluorescent determination of paranitrophenol
US8961825B2 (en) Fluorescent silica nanoparticles through silica densification
Wu et al. Magnetic nanobead-based immunoassay for the simultaneous detection of aflatoxin B1 and ochratoxin A using upconversion nanoparticles as multicolor labels
Saleh et al. Detection of biotin–avidin affinity binding by exploiting a self-referenced system composed of upconverting luminescent nanoparticles and gold nanoparticles
Li et al. Classification, synthesis, and application of luminescent silica nanoparticles: a review
CN112898965B (en) Preparation and use method of ratiometric fluorescent probe for visual differential detection
CN104910917B (en) A kind of ratio probes of embedding Two Colour Fluorescence quantum dot and preparation method thereof
CN107603593A (en) A kind of Ratiometric fluorescent probe and its application for preparing and detecting glutathione
CN109705840A (en) The preparation method of high luminescent quantum dot fluorescent microsphere based on affine assembling
CN111790324B (en) Multi-level controllable assembled fluorescent-magnetic bifunctional microsphere and preparation method and application thereof
CN103988081A (en) Metal/silica core/shell nanoparticles, manufacturing process and immunochromatographic test device comprising such nanoparticles
Chen et al. Architecting ultra-bright silanized carbon dots by alleviating the spin-orbit coupling effect: a specific fluorescent nanoprobe to label dead cells
CN107384375B (en) A kind of rare earth luminous silicon dioxide hybrid materials and its preparation method and application
CN109762557B (en) Inorganic fluorescent nano particle and preparation method and application thereof
Xu et al. A ratiometric nanosensor based on lanthanide-functionalized attapulgite nanoparticle for rapid and sensitive detection of bacterial spore biomarker
Wang et al. Dye-loaded zeolite L@ silica core-shell composite functionalized with europium (III) complexes for dipicolinic acid detection
CN109735325A (en) A kind of composite material using quantum dot enhancing up-conversion luminescence
Huang et al. Sensitive detection of carcinoembryonic antigen with magnetic nano-bead and upconversion nanoparticles-based immunoassay
CN112500847B (en) Cadmium ion probe based on quantum dot fluorescence resonance energy transfer system and preparation method thereof
CN110330478A (en) Naphthalimide organic fluorescent gel compound and preparation method, organogel and application
JP5782643B2 (en) Glass-coated gold nanoparticles and fluorescence-enhanced gold nanoparticles and methods for producing them
CN110776905B (en) Quantum dot fluorescent nanosphere based on amphiphilic silicon carrier and preparation method thereof
Sui et al. Fluorescent (Au@ SiO 2) SiC nanohybrids: influence of gold nanoparticle diameter and SiC nanoparticle surface density

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