CN113369489B - Luminescent silver nanocluster and preparation method and application thereof - Google Patents
Luminescent silver nanocluster and preparation method and application thereof Download PDFInfo
- Publication number
- CN113369489B CN113369489B CN202110524081.5A CN202110524081A CN113369489B CN 113369489 B CN113369489 B CN 113369489B CN 202110524081 A CN202110524081 A CN 202110524081A CN 113369489 B CN113369489 B CN 113369489B
- Authority
- CN
- China
- Prior art keywords
- solution
- silver nanocluster
- fluorescence
- luminescent
- mercapto
- 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
Links
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F9/00—Making metallic powder or suspensions thereof
- B22F9/16—Making metallic powder or suspensions thereof using chemical processes
- B22F9/18—Making metallic powder or suspensions thereof using chemical processes with reduction of metal compounds
- B22F9/24—Making metallic powder or suspensions thereof using chemical processes with reduction of metal compounds starting from liquid metal compounds, e.g. solutions
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B82—NANOTECHNOLOGY
- B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
- B82Y30/00—Nanotechnology for materials or surface science, e.g. nanocomposites
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B82—NANOTECHNOLOGY
- B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
- B82Y40/00—Manufacture or treatment of nanostructures
-
- 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"
-
- 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
- G01N21/6486—Measuring fluorescence of biological material, e.g. DNA, RNA, cells
-
- 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"
- G01N2021/6432—Quenching
Abstract
The invention relates to a luminescent silver nanocluster and a preparation method and application thereof, wherein 2-14 mmol/L2-mercapto-5-benzimidazole sodium sulfonate aqueous solution and 1mmol/L silver nitrate solution are mixed in equal volume to obtain mixed solution; and uniformly stirring the mixed solution, adding sufficient 0.1 mol/L ascorbic acid, uniformly stirring, adding a NaOH solution to adjust the pH to 7, controlling the heating temperature to be 40-100 ℃, refluxing for 2-24 h, cooling, taking out, dialyzing and purifying to obtain the luminescent silver nanocluster. The preparation method has the advantages of simple preparation process, simple reaction conditions and environmental friendliness, and the prepared luminescent silver nanocluster has the advantages of good water solubility, good stability, high quantum yield and the like, and can be applied to high-sensitivity and high-selectivity Cu identification and detection 2+ And the detection process is simple, convenient and quick, and the detection result is accurate.
Description
Technical Field
The invention relates to preparation of a silver nanocluster, and particularly relates to a preparation method and application of a green fluorescent silver nanocluster.
Background
Copper ion (Cu) 2+ ) Is the third content in human bodyHigh transition metal elements play a crucial role in both environment and biological systems, such as transport, activation, and electrical signal conversion of oxygen molecules. Copper is also a cofactor for many oxidases (e.g., superoxide dismutase) because it can undergo Cu (I)/Cu (II) conversion and is thus critical for iron absorption and utilization. However, cu in vivo 2+ May have long-term adverse effects on the liver, kidney and nervous system, thereby seriously impairing human health, resulting in diseases such as Alzheimer's disease, mengxi disease, parkinson's disease, etc. Cu in drinking water according to the United States Environmental Protection Agency (USEPA) standard 2+ The maximum allowable limit of (2) is 1.3 ppm (about 20.0. Mu.M). Due to the Cu content 2+ Are widely used in electronic device production and industrial and agricultural processes, so Cu 2+ Contamination of (2) has been a problem. Therefore, there is a need for a sensitive and selective method for detecting Cu in environmental and biological samples 2+ Thereby being applied to environmental supervision and disease treatment.
To date, a number of assays for Cu have been established 2+ Such as atomic absorption/emission spectroscopy (AAS/AES), inductively coupled plasma mass spectrometry (ICP-MS), electrochemistry, dynamic Light Scattering (DLS), raman scattering, and the like. However, these methods have the disadvantages of expensive equipment, complicated operation or time consumption. In recent years, fluorescence analysis methods have been widely studied in the field of analytical detection due to the advantages of easy operation, high sensitivity, fast signal response, low cost, real-time detection, almost no damage to samples, and the like. Therefore, a high-selectivity and high-accuracy fluorescence analysis method is constructed to detect Cu 2+ Is very important.
The metal nano-cluster is an ultra-small nano-particle with the size less than 2 nm, has the advantages of strong fluorescence property, large Stokes displacement, good light stability and water solubility, strong photobleaching resistance and the like, and is widely applied to the biochemical aspects of biosensing, cell imaging, cancer treatment and the like. The high cost of gold in various metal nanoclusters limits the wide application of gold nanoclusters due to the oxidation potential (E) of copper 0 ox = -0.34 V）Silver (E) 0 ox = -0.80V) and gold (E) 0 ox = 1.50V), copper nanoclusters are more easily oxidized in aqueous media or exposed to the external environment. Therefore, in recent years, silver nanoclusters (Ag NCs) have been a hot point of research in the field of analytical sensing. Currently, ag NCs have been successfully synthesized using various ligands (e.g., amino acids, dendrimers, proteins, thiols, and DNA), among which thiolates are the most commonly used candidates for the preparation of stable and monodisperse Ag NCs due to their strong affinity for Ag surfaces.
However, the preparation method of the silver nanoclusters (Ag NCs) generally has some defects, the synthesis method is complicated, and an additional strong reducing agent such as sodium borohydride NaBH is often required to be added 4 Such as: min Yang et al (Journal of Alloys and Compounds, 2019, 781, 1021-1027) synthesizes silver nanoparticles by taking PVP as a ligand template, sodium borohydride as a reducing agent and adopting a seed crystal method on the basis of adding ascorbic acid. Xiaodong Lin et al (Microchimica Acta, 2019, 186: 648) reacted AgNO 3 And mixing the solution and the DNA solution, incubating for 30 minutes, adding sodium borohydride serving as a reducing agent, and placing in a dark environment at 4 ℃ overnight to obtain the fluorescent AgNCs. Guizou Yue et al (Sensors and activators B,2019, 287: 408-415) react BSA with AgNO 3 And mixing under an alkaline condition, and stirring for 2 hours at room temperature by using sodium borohydride as a reducing agent to obtain the fluorescent AgNCs. Some of them need to add organic compound in the synthesis process or carry out photocatalysis reaction, chuanxi Wang et al (Sensors and activators B,2017, 238: 1136-1143) use glutathione GSH as ligand and hydrazine hydrate as reducer, ultrasonic process for 15 minutes, precipitate silver nanocluster by adding isopropanol, and centrifugally disperse in aqueous solution to obtain fluorescent AgNCs. Xixiandong et al (journal of inorganic chemistry 2014, 30 (10), 2341-2346) extracts AgNO 3 And 3, 4-dihydroxy-L-phenylalanine under alkaline conditions (pH value is adjusted to 8.0 by NaOH), and the fluorescent silver nanocluster is obtained after 1h of sunlight irradiation. These limitations limit the wide application of Ag NCs in the analytical field, and some synthetic methods have low fluorescence quantum yield of silver nanoclusters (Hubei university school report)(natural science edition), 2021, 43 (2): 185-191) are used, which is disadvantageous for their application in biosensing and biomarkers, etc. In view of this, it is extremely necessary to develop Ag NCs with high fluorescence quantum yield and green and simple synthesis process.
TABLE 1 detection of Cu based on fluorescent nanomaterials 2+ Comparison of fluorescence analysis method
| Fluorescent materials | Linear range (μ mol/L) | Detection limit (nmol/L) | References |
| hPEI-AgNCs | 0.01-7.70 | 10.00 | [Analytical Chemistry, 2014, 86(1): 419-426] |
| hPEI-CuNCs | 0.02-8.80 | 8.90 | [Analytica Chimica Acta, 2015, 895: 95-103] |
| Cytidne-Cu NCs | 0.05-2.00 | 32 | [RSC Advances, 2018, 8(17): 9057-9062] |
| GSH-AuNC/Ag + complex | 0.02-10.00 | 12 | [Analytica Chimica Acta, 2019, 1088: 116-122] |
| dNSiO 2 −AuAg NCs | 0.20-2.00 | 60 | [ACS Applied Materials & Interfaces, 2019, 11 (23): 21150-21158] |
At present, a fluorescence sensing method based on metal nanoclusters is applied to Cu 2+ The detection of (2) generally has the problem of insufficient detection limit, as shown in Table 1, high-sensitivity Cu is established 2+ The novel detection method also has very important research significance.
Disclosure of Invention
The invention aims to provide a luminescent silver nanocluster, a preparation method and application thereof, which can at least improve Cu content 2+ Sensitivity and selectivity of detection.
In order to achieve the above object, according to one aspect of the present invention, there is provided a method for preparing a luminescent silver nanocluster, comprising mixing an aqueous solution of 2-14 mmol/L sodium 2-mercapto-5-benzimidazole sulfonate with a 1mmol/L silver nitrate solution in equal volume to obtain a mixed solution; and uniformly stirring the mixed solution, adding sufficient 0.1 mol/L ascorbic acid, uniformly stirring, adding a NaOH solution to adjust the pH to 7, controlling the heating temperature to be 40-100 ℃, refluxing for 2-24 h, cooling, taking out, dialyzing and purifying to obtain the luminescent silver nanocluster.
Furthermore, the concentration of the 2-mercapto-5-benzimidazole sodium sulfonate aqueous solution is 5-11 mmol/L.
Further, the concentration of the 2-mercapto-5-benzimidazole sodium sulfonate aqueous solution is 8 mmol/L.
Further, the heating temperature is controlled to be 60-80 ℃ and the reflux is carried out for 6-16 h.
Further, the heating temperature was controlled to 60 ℃ for 10 hours of reflux.
Further, after stirring uniformly, 0.1 mol/L NaOH was added to adjust the pH of the solution to 7.
According to another aspect of the present invention, there is provided a luminescent silver nanocluster prepared by the above-described method.
According to another aspect of the present invention, there is provided the luminescent silver nanoclusters as described above as a fluorescent probe for detecting Cu 2+ The use of (1).
Compared with the prior art, the invention has the beneficial effects that:
(1) The invention adopts 2-mercapto-5-benzimidazole sodium sulfonate as a ligand protective agent and ascorbic acid as a reducing agent for the first time to prepare the silver nanocluster with good luminescence property, the preparation process is simple and environment-friendly, the fluorescence emission peak is about 520 nm, when the silver nanocluster is observed by a black background under ultraviolet light, strong green fluorescence is presented, and the fluorescence quantum yield can reach 25.3%.
(2) The 2-mercapto-5-benzimidazole sodium sulfonate is a compound with mercapto groups and imidazole rings, the contained mercapto groups can form a strong bonding effect with noble metals, and the sulfonic groups contained in the 2-mercapto-5-benzimidazole sodium sulfonate can enable the prepared fluorescent silver nano cluster to have good water solubility and good biocompatibility.
(3) The luminescent silver nanocluster prepared by the invention is Cu 2+ Shows high sensitivity and selectivity and can be applied to Cu 2+ The detection limit can reach 1.77 nM.
Drawings
FIG. 1 is a fluorescence excitation and emission spectrum of luminescent silver nanoclusters of example 9;
fig. 2 is a pH stability plot of luminescent silver nanoclusters of example 9;
fig. 3 is a graph of the storage stability of the luminescent silver nanoclusters of example 9;
FIG. 4 is the luminescent silver nanoclusters versus copper ions (Cu) of example 9 2+ ) A responsive operating curve;
FIG. 5 shows the variation of the relative fluorescence intensity of the luminescent silver nanoclusters of example 9 with copper ions (Cu) 2+ ) A linear relationship between concentrations;
fig. 6 is a bar graph of fluorescence of the luminescent silver nanoclusters of example 9 after interaction with various metal ions.
Detailed Description
The invention provides a preparation method of a luminescent silver nanocluster, which is characterized in that 2-14 mmol/L2-mercapto-5-benzimidazole sodium sulfonate aqueous solution and 1mmol/L silver nitrate solution are mixed in equal volume to obtain mixed solution; and uniformly stirring the mixed solution, adding sufficient 0.1 mol/L ascorbic acid, uniformly stirring, adding NaOH solution to adjust the pH to 7, controlling the heating temperature to be 40-100 ℃ for refluxing for 2-24 h, cooling, taking out, dialyzing and purifying to obtain the luminescent silver nanocluster.
According to the above embodiment, the process of forming the luminescent silver nanoclusters of the present invention is: firstly, 2-mercapto-5-benzimidazole sodium sulfonate is coordinated with monovalent silver Ag (I) through mercapto (-SR) under stirring at room temperature to form an Ag (I) -thiolate complex; then adding weak reducing agent ascorbic acid, adding NaOH to adjust the pH value to 7, wherein the pKa of benzimidazole in the sodium 2-mercapto-5-benzimidazole sulfonate dihydrate is about 5.53, so that imidazole ring is an electron-rich center, the reducibility of the imidazole ring is enhanced, and Ag (I) can be selectively reduced to Ag (0) in the presence of the ascorbic acid, and the Ag (0) can be separated from the Ag (I) -thiolate complex by the sodium 2-mercapto-5-benzimidazole sulfonate dihydrate to form an Ag (0) -Ag (I) -thiolate intermediate; and when the Ag (0) -Ag (I) -thiolate intermediate is refluxed at the heating temperature of 40-100 ℃, ag (0) collides and fuses to form an Ag (0) core and a shell structure of an Ag (I) -thiolate complex, and the light-emitting silver nanocluster is formed.
In order to obtain better quantum yield and fluorescence lifetime, the concentration of the 2-mercapto-5-benzimidazole sodium sulfonate aqueous solution is 5-11 mmol/L as a preferred embodiment. Further preferably, the concentration of the 2-mercapto-5-benzimidazole sodium sulfonate aqueous solution is 8 mmol/L.
In order to obtain better quantum yield and fluorescence lifetime, as a preferred embodiment, the heating temperature is controlled to be 60-80 ℃ for refluxing for 6-16 h, and further preferably, the heating temperature is controlled to be 60 ℃ for refluxing for 10 h.
Luminescent silver nanocluster pair Cu prepared by adopting method 2+ Shows high sensitivity and selectivity and can be used for constructing Cu 2+ The detection sensor system of (1).
The claimed solution is further illustrated by the following examples. However, the examples and comparative examples are intended to illustrate the embodiments of the present invention without departing from the scope of the subject matter of the present invention, and the scope of the present invention is not limited by the examples. Unless otherwise specifically indicated, the materials and reagents used in the present invention are available from commercial products in the art.
Example 1
Mixing 10ml of 2mmol/L2-mercapto-5-benzimidazole sodium sulfonate aqueous solution and 10ml of 1mmol/L silver nitrate solution, uniformly stirring the mixed solution, adding 1 mL of 0.1 mol/L ascorbic acid, uniformly stirring, adding 0.1 mol/L NaOH to adjust the pH value of the solution to 7, controlling the heating temperature to be 100 ℃, refluxing for 24 hours, cooling, taking out, dialyzing and purifying to obtain the luminescent silver nanocluster. The fluorescence emission peak of the luminescent silver nanocluster is about 520 nm, and under ultraviolet light, when the luminescent silver nanocluster is observed on a black background, relatively strong green fluorescence is presented, the quantum yield is 15.2%, and the fluorescence life is 7.23 mus.
Example 2
Mixing 10ml of 5 mmol/L2-mercapto-5-benzimidazole sodium sulfonate aqueous solution and 10ml of 10mmol/L silver nitrate solution, uniformly stirring the mixed solution, adding 1 mL of 0.1 mol/L ascorbic acid, uniformly stirring, adding 0.1 mol/L NaOH to adjust the pH value of the solution to 7, controlling the heating temperature to be 80 ℃, refluxing for 20 hours, cooling, taking out, dialyzing and purifying to obtain the luminescent silver nanocluster. The fluorescence emission peak of the luminescent silver nanocluster is about 520 nm, and under ultraviolet light, when the luminescent silver nanocluster is observed on a black background, relatively strong green fluorescence is presented, the quantum yield is 17.8%, and the fluorescence life is 13.25 mus.
Example 3
Mixing 10ml of 111mmol/L2-mercapto-5-benzimidazole sodium sulfonate aqueous solution and 10ml of 1mmol/L silver nitrate solution, uniformly stirring the mixed solution, adding 1 mL of 0.1 mol/L ascorbic acid, uniformly stirring, adding 0.1 mol/L NaOH to adjust the pH value of the solution to 7, controlling the heating temperature to be 60 ℃, refluxing for 16 hours, cooling, taking out, dialyzing and purifying to obtain the luminescent silver nanocluster. The fluorescence emission peak of the luminescent silver nanocluster is about 520 nm, and under ultraviolet light and observation on a black background, relatively strong green fluorescence is presented, the quantum yield is 16.8%, and the fluorescence life is 17.12 mu s.
Example 4
Mixing 10ml of 14mmol/L2-mercapto-5-benzimidazole sodium sulfonate aqueous solution and 10ml of 10mmol/L silver nitrate solution, uniformly stirring the mixed solution, adding 1 mL of 0.1 mol/L ascorbic acid, uniformly stirring, adding 0.1 mol/L NaOH to adjust the pH value of the solution to 7, controlling the heating temperature to be 40 ℃, refluxing for 12 hours, cooling, taking out, dialyzing and purifying to obtain the luminescent silver nanocluster. The fluorescence emission peak of the luminescent silver nanocluster is about 520 nm, and under ultraviolet light, when the luminescent silver nanocluster is observed on a black background, relatively strong green fluorescence is presented, the quantum yield is 19.3%, and the fluorescence life is 15.19 mus.
Example 5
Mixing 10ml of 8mmol/L2-mercapto-5-benzimidazole sodium sulfonate aqueous solution and 10ml of 10mmol/L silver nitrate solution, uniformly stirring the mixed solution, adding 1 mL of 0.1 mol/L ascorbic acid, uniformly stirring, adding 0.1 mol/L NaOH to adjust the pH value of the solution to 7, controlling the heating temperature to be 60 ℃, refluxing for 2 hours, cooling, taking out, dialyzing and purifying to obtain the luminescent silver nanocluster. The fluorescence emission peak of the luminescent silver nanocluster is about 520 nm, and under ultraviolet light, when the luminescent silver nanocluster is observed on a black background, relatively strong green fluorescence is presented, the quantum yield is 11.3%, and the fluorescence life is 6.29 mus.
Example 6
Mixing 10ml of 8mmol/L2-mercapto-5-benzimidazole sodium sulfonate aqueous solution and 10ml of 10mmol/L silver nitrate solution, uniformly stirring the mixed solution, adding 1 mL of 0.1 mol/L ascorbic acid, uniformly stirring, adding 0.1 mol/L NaOH to adjust the pH value of the solution to 7, controlling the heating temperature to be 60 ℃, refluxing for 4 hours, cooling, taking out, dialyzing and purifying to obtain the luminescent silver nanocluster. The fluorescence emission peak of the luminescent silver nanocluster is about 520 nm, and under ultraviolet light, when the luminescent silver nanocluster is observed on a black background, relatively strong green fluorescence is presented, the quantum yield is 13.7%, and the fluorescence life is 12.38 mus.
Example 7
Mixing 10ml of 8mmol/L2-mercapto-5-benzimidazole sodium sulfonate aqueous solution and 10ml of 10mmol/L silver nitrate solution, uniformly stirring the mixed solution, adding 1 mL of 0.1 mol/L ascorbic acid, uniformly stirring, adding 0.1 mol/L NaOH to adjust the pH value of the solution to 7, controlling the heating temperature to be 60 ℃, refluxing for 6 hours, cooling, taking out, dialyzing and purifying to obtain the luminescent silver nanocluster. The fluorescence emission peak of the luminescent silver nanocluster is about 520 nm, and under ultraviolet light, when the luminescent silver nanocluster is observed on a black background, relatively strong green fluorescence is presented, the quantum yield is 18.1%, and the fluorescence life is 15.24 mus.
Example 8
Mixing 10ml of 8mmol/L2-mercapto-5-benzimidazole sodium sulfonate aqueous solution and 10ml of 10mmol/L silver nitrate solution, uniformly stirring the mixed solution, adding 1 mL of 0.1 mol/L ascorbic acid, uniformly stirring, adding 0.1 mol/L NaOH to adjust the pH value of the solution to 7, controlling the heating temperature to be 60 ℃, refluxing for 8 hours, cooling, taking out, dialyzing and purifying to obtain the luminescent silver nanocluster. The fluorescence emission peak of the luminescent silver nanocluster is about 520 nm, and under ultraviolet light and observation on a black background, relatively strong green fluorescence is presented, the quantum yield is 20.7%, and the fluorescence life is 16.14 mu s.
Example 9
Mixing 10ml of 8mmol/L2-mercapto-5-benzimidazole sodium sulfonate aqueous solution and 10ml of 10mmol/L silver nitrate solution, uniformly stirring the mixed solution, adding 1 mL of 0.1 mol/L ascorbic acid, uniformly stirring, adding 0.1 mol/L NaOH to adjust the pH value of the solution to 7, controlling the heating temperature to be 60 ℃, refluxing for 10 hours, cooling, taking out, dialyzing and purifying to obtain the luminescent silver nanocluster. The fluorescence emission peak of the luminescent silver nanocluster is about 520 nm, and under ultraviolet light, when the luminescent silver nanocluster is observed on a black background, relatively strong green fluorescence is presented, the quantum yield is 25.3%, and the fluorescence life is 19.38 mus.
To a fluorescence cuvette containing 1000. Mu.L of PBS buffer solution (100 mmol/L, pH = 7) was added 100. Mu.L of the luminescent silver nanocluster solution obtained in example 9, and fluorescence excitation and emission spectra thereof were measured, as shown in FIG. 1, with a fluorescence emission peak at 520 nm.
The luminescent silver nanocluster solution is placed in different pH environments, the influence of pH on the fluorescence intensity of the silver nanocluster is researched, as shown in fig. 2, the fluorescence intensity of the luminescent silver nanocluster solution does not change too much in the pH (3-9) range, and the fact that the luminescent silver nanocluster can still maintain a stable structure in the acidic and alkaline environments is proved. The wide pH application range enables the silver nanoclusters to be well applied to actual samples.
The fluorescent silver nanocluster aqueous solution is placed at room temperature, the fluorescence intensity of the fluorescent silver nanocluster aqueous solution at the 520 nm position is detected regularly, as shown in fig. 3, the fluorescence intensity value is basically kept unchanged after 6 months, and the fact that the fluorescent silver nanocluster has good light stability to outside air, a solution system and the like is shown.
Comparative example 1
Mixing AgNO 3 The aqueous solution (4.1 mg,1 mL) was added to 20 mL of water at 650 r 8729min -1 An aqueous solution of sodium 2-mercapto-5-benzimidazole sulfonate (13.84 mg,0.48 mL) was added with stirring. Then, at 650 r 8729min -1 Rapidly add NaBH with stirring 4 In aqueous solution (2.7 mg,1 mL), the color of the solution immediately turned brown-black. The reaction was stirred for a further 5 hours, 1-butanol (16 mL) and methanol (4 mL) were added to the resulting solution with vigorous stirring at 6000 r 8729min -1 After centrifugation for 5 minutes, the supernatant was removed, and this process was repeated 5 times to obtain silver nanoparticles. Under ultraviolet light, no significant fluorescence was observed with the naked eye on a black background.
Comparative example 2
Mixing 10ml of 8mmol/L2-mercapto-5-benzimidazole sodium sulfonate aqueous solution and 10ml of 1mmols/L silver nitrate solution, uniformly stirring the mixed solution, adding 0.1 mol/L NaOH to adjust the pH value of the solution to 7, stirring for 10 min, and then carrying out ultrasonic treatment on the reaction mixture for 15 min at the power of 300W to obtain the silver nanocluster solution. Under the ultraviolet light, when the fluorescent material is observed on a black background, no obvious fluorescence can be observed by naked eyes.
Comparative example 3
Mixing 10ml of 8mmol/L2-mercapto-5-benzimidazole sodium sulfonate aqueous solution and 10ml of 10mmol/L silver nitrate solution, uniformly stirring the mixed solution, adding 0.1 mol/L NaOH to adjust the pH value of the solution to 7, controlling the heating temperature to be 60 ℃, refluxing for 24 hours, and taking out after cooling to obtain the silver nanocluster. Under ultraviolet light, no significant fluorescence was observed with the naked eye on a black background.
Comparative example 4
Mixing 10mL of penicillamine aqueous solution at 8mmol/L and 10mL of silver nitrate solution at 10mmol/L, uniformly stirring the mixed solution, adding 1 mL of 0.1 mol/L ascorbic acid, uniformly stirring, adding 0.1 mol/L NaOH to adjust the pH value of the solution to 7, controlling the heating temperature to be 60 ℃ for refluxing for 10 hours, cooling, taking out, dialyzing and purifying to obtain the luminescent silver nanocluster. The fluorescence emission peak of the luminescent silver nanocluster is about 450 nm, the quantum yield is 0.15%, and the fluorescence lifetime is 6.5ns.
Comparative examples 1 to 4 as comparative examples to example 9, the results are shown in Table 2, in which silver precursor and protective agent used in example 9 and comparative examples 1 to 3 were silver nitrate and sodium 2-mercapto-5-benzimidazole sulfonate, ascorbic acid was added as a reducing agent in example 9, and heat was applied to assist the reaction, and NaBH was used in comparative example 1 4 As the reducing agent, the ultrasonic-assisted reduction adopted in comparative example 2 and the ultrasonic-assisted reduction adopted in comparative example 3 did not add any reducing agent, and the heating time was prolonged. The protectant used in comparative example 4 was penicillamine.
From the comparison results, the product of example 9 fluoresced green at 520 nm with a fluorescence quantum yield of 25.3%, whereas the reaction products of comparative examples 1-3 did not produce significant fluorescence. The product of comparative example 4 fluoresced blue at 450 nm with a fluorescence quantum yield of 0.15%. Compared with the product of the comparative example, the fluorescence property of the product of the invention is obviously improved, in addition, sodium borohydride belongs to a flammable hazardous material meeting humidity, can be spontaneously combusted in humid air, can be decomposed to release a large amount of hydrogen when meeting water or acid, and simultaneously generates high heat, so that the hydrogen can be ignited to cause explosion accidents, and the product is not suitable for wide industrial application. The human tissue can be caused to slightly generate heat under the influence of high-frequency sound waves for a long time, when the frequency is higher than that of ultrasonic waves, the heat is more and more serious, water molecules in the human body are burnt, surrounding tissues are damaged, and the ultrasonic waves are more dangerous if not controlled, so that the haemorrhage, the inflammation and the arthritis can be caused.
TABLE 2
| Silver nanocluster precursor | Protecting agent | Reducing agent | Auxiliary reaction mode | Reaction time | Emitting fluorescence | |
| Example 9 | Silver nitrate | 2-mercapto-5-benzimidazole sodium sulfonate | Ascorbic acid | Heating of | 10 |
520 nm green fluorescence |
| Comparative example 1 | Silver nitrate | 2-mercapto-5-benzimidazole sodium sulfonate | NaBH 4 | Is composed of | 5 h | Is free of |
| Comparative example 2 | Silver nitrate | 2-mercapto-5-benzimidazole sodium sulfonate | Is free of | |
15 min | Is free of |
| Comparative example 3 | Silver nitrate | 2-mercapto-5-benzimidazole sodium sulfonate | Is composed of | Heating of | 24 h | Is free of |
| Comparative example 4 | Silver nitrate | Penicillin amines | Ascorbic acid | Heating of | 10 |
450 nm blue fluorescence |
Example 10 (luminescent silver nanoclusters in Cu 2+ In the detection of (2)
Taking the luminescent silver nanoclusters obtained in example 9 as an example, 100 μ L of the water-soluble luminescent silver nanoclusters and 1000 μ L of a PBS buffer solution (100 mmol/L, pH = 7) were injected into a fluorescence cuvette, stirred until uniform mixing, and mixed as Cu 2+ The solution concentration is added into a fluorescence cuvette from small to large, and the fluorescence spectra are respectively measured by taking 340 nm as the excitation wavelength. As shown in fig. 4, with Cu 2+ The fluorescence of the silver nanoclusters is gradually quenched due to the increase of the concentration; as shown in FIG. 5, cu was added 2+ Ratio of fluorescence intensities of front and rear 0 F and Cu 2+ The ratio of fluorescence intensity in the graph is F 0 Is represented by/F, wherein F 0 And F each represents Cu 2+ The fluorescence intensity of the silver nanoclusters in the absence and the presence is obtained through linear fitting, and the regression equation of the silver nanoclusters is as follows: y =1.0900+0.1039X (Y means F 0 X denotes Cu 2+ Concentration) with a linear coefficient of R 2 =0.995。Cu 2+ The detection limit of (2) is 1.77 nM (calculated according to the formula LOD =3 σ/k, σ is standard deviation of fluorescence intensity values of the silver nanoclusters for 11 times, and k is the slope of the fitted straight line in FIG. 6). Based on the method, the water-soluble luminescent silver nanocluster can be applied to Cu in practical samples 2+ The detection of (3).
Example 11
Taking the luminescent silver nanoclusters obtained in example 9 as an example, 100 μ L of water-soluble luminescent silver nanoclusters and 1000 μ L of PBS buffer solution (100 mmol/L, pH = 7) were injected into a fluorescence cuvette, and first, cu was added 2+ Adding the above-mentioned material, measuring its fluorescence intensity as blank control; then 16 common cations (the concentration of coexisting ions is Cu) are added respectively 2+ 100 times of the amount of the potential interfering substance), measuring the fluorescence intensity value of the potential interfering substance and recording the fluorescence intensity value; then adding Cu thereto 2+ And then measuring and recording the fluorescence intensity. The fluorescence spectra were measured at 340 nm as the excitation wavelength, and histograms of the fluorescence intensities at 520 nm for different ions were plotted, as shown in FIG. 6. Experiments prove that other cations do not interfere the system to Cu 2+ Detection of (3).
15 cations are respectively Na + 、K + 、Ca 2+ 、Mg 2+ 、Zn 2+ 、Mn 2+ 、Fe 3+ 、Fe 2+ 、Co 2+ 、Ni 2+ 、Cd 2+ 、Pb 2+ 、Ba 2 + 、Sr 2+ 、Cr 3+ 、NH 4 + 。
The preparation method has the advantages of simple preparation process, simple reaction conditions and environmental friendliness, the prepared water-soluble luminescent silver nanocluster has good stability, and the water-soluble luminescent silver nanocluster prepared by the method can be used for Cu 2+ The detection of (3).
Claims (6)
1. Method for detecting Cu by using luminescent silver nanocluster as fluorescent probe 2+ The application of (1), which is characterized in that: the preparation method of the luminescent silver nanocluster comprises the steps of mixing 2-14 mmol/L aqueous solution of 2-mercapto-5-benzimidazole sodium sulfonate and 1mmol/L silver nitrate solution in equal volume to obtain mixed solution; uniformly stirring the mixed solution, adding sufficient 0.1 mol/L ascorbic acid, uniformly stirring, adding NaOH solution to adjust the pH to 7, controlling the heating temperature to be 40-100 ℃ for refluxing for 2-24 h, cooling, taking out, dialyzing and purifying to obtain the luminescent silver nanocluster; the fluorescence emission peak of the luminescent silver nanocluster is 520 nm, and the luminescent silver nanocluster presents strong green fluorescence when observed with a black background under ultraviolet light.
2. Use according to claim 1, characterized in that: the concentration of the 2-mercapto-5-benzimidazole sodium sulfonate aqueous solution is 5-11 mmol/L.
3. Use according to claim 2, characterized in that: the concentration of the 2-mercapto-5-benzimidazole sodium sulfonate aqueous solution is 8 mmol/L.
4. Use according to claim 1, characterized in that: heating at 60-80 deg.C under reflux for 6-16 h.
5. Use according to claim 1, characterized in that: the heating temperature is controlled to 60 ℃ and reflux is carried out for 10 h.
6. Use according to claim 1, characterized in that: after stirring uniformly, 0.1 mol/L NaOH is added to adjust the pH value of the solution to 7.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110524081.5A CN113369489B (en) | 2021-05-13 | 2021-05-13 | Luminescent silver nanocluster and preparation method and application thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110524081.5A CN113369489B (en) | 2021-05-13 | 2021-05-13 | Luminescent silver nanocluster and preparation method and application thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113369489A CN113369489A (en) | 2021-09-10 |
| CN113369489B true CN113369489B (en) | 2023-03-07 |
Family
ID=77570873
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110524081.5A Active CN113369489B (en) | 2021-05-13 | 2021-05-13 | Luminescent silver nanocluster and preparation method and application thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113369489B (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114806548B (en) * | 2022-04-29 | 2022-12-30 | 山西大学 | Red fluorescent silver nanocluster, preparation method thereof and application of red fluorescent silver nanocluster in detection of copper ions |
| CN115096976B (en) * | 2022-06-20 | 2024-01-26 | 商丘师范学院 | Silver cluster/nitrogen-doped carbon electrode material, in-situ finite field synthesis method and application thereof |
| CN116144352B (en) * | 2023-01-09 | 2023-11-24 | 西华师范大学 | Gold-silver bimetallic nanocluster for sulfide visual detection and preparation method thereof |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102554217A (en) * | 2012-02-24 | 2012-07-11 | 河南大学 | Water-soluble nano-copper and preparation method thereof |
| CN105772742A (en) * | 2016-05-12 | 2016-07-20 | 山西大学 | Preparation method and application of fluorogold nanocluster |
| CN109266333A (en) * | 2018-10-23 | 2019-01-25 | 山西大学 | A kind of preparation method and application of Fluorescent silver nanocluster probe |
| CN110819343A (en) * | 2019-11-14 | 2020-02-21 | 山西大学 | Preparation method and application of red fluorescent copper nanocluster |
| CN112175608A (en) * | 2020-10-22 | 2021-01-05 | 江南大学 | Blue fluorescent silver nanocluster and preparation method and application thereof |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2009078815A1 (en) * | 2007-12-14 | 2009-06-25 | Nanyang Technological University | A nanostructured material loaded with noble metal particles |
| US11427602B2 (en) * | 2018-06-15 | 2022-08-30 | Industry-University Cooperation Foundation Hanyang University Erica Campus | Bimetallic nanoparticles with stimuli-responsiveness, process for producing the same, and use thereof |
-
2021
- 2021-05-13 CN CN202110524081.5A patent/CN113369489B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102554217A (en) * | 2012-02-24 | 2012-07-11 | 河南大学 | Water-soluble nano-copper and preparation method thereof |
| CN105772742A (en) * | 2016-05-12 | 2016-07-20 | 山西大学 | Preparation method and application of fluorogold nanocluster |
| CN109266333A (en) * | 2018-10-23 | 2019-01-25 | 山西大学 | A kind of preparation method and application of Fluorescent silver nanocluster probe |
| CN110819343A (en) * | 2019-11-14 | 2020-02-21 | 山西大学 | Preparation method and application of red fluorescent copper nanocluster |
| CN112175608A (en) * | 2020-10-22 | 2021-01-05 | 江南大学 | Blue fluorescent silver nanocluster and preparation method and application thereof |
Non-Patent Citations (2)
| Title |
|---|
| Ag7(MBISA)6 Nanoclusters Conjugated with Quinacrine for FRET-Enhanced Photodynamic Activity under Visible Light Irradiation;TOMINAGA C.等;《Acta Physico-Chimica Sinica》;20171027;全文 * |
| 用于检测汞离子的纳米光学传感器的研究进展;田春霞;《理化检验(化学分册)》;20171018(第10期);全文 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN113369489A (en) | 2021-09-10 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN113369489B (en) | Luminescent silver nanocluster and preparation method and application thereof | |
| Chen et al. | CuMnO2 nanoflakes as pH-switchable catalysts with multiple enzyme-like activities for cysteine detection | |
| Sun et al. | Fluorescent Au nanoclusters: recent progress and sensing applications | |
| Dugandžić et al. | A SERS-based molecular sensor for selective detection and quantification of copper (II) ions | |
| Xia et al. | Fast, high-yield synthesis of amphiphilic Ag nanoclusters and the sensing of Hg 2+ in environmental samples | |
| Yang et al. | Novel synthesis of gold nanoclusters templated with l-tyrosine for selective analyzing tyrosinase | |
| Dai et al. | One-pot synthesis of bovine serum albumin protected gold/silver bimetallic nanoclusters for ratiometric and visual detection of mercury | |
| Liu et al. | Assembly-enhanced fluorescence from metal nanoclusters and quantum dots for highly sensitive biosensing | |
| Miao et al. | BSA capped bi-functional fluorescent Cu nanoclusters as pH sensor and selective detection of dopamine | |
| Shojaeifard et al. | Bimetallic AuCu nanoclusters-based florescent chemosensor for sensitive detection of Fe3+ in environmental and biological systems | |
| Liu et al. | Recent progress on gold-nanocluster-based fluorescent probe for environmental analysis and biological sensing | |
| Gao et al. | A highly sensitive ratiometric fluorescent sensor for copper ions and cadmium ions in scallops based on nitrogen doped graphene quantum dots cooperating with gold nanoclusters | |
| CN110862820B (en) | Preparation method and application of cysteine-gold nanocluster | |
| Gao et al. | Facile, rapid one-pot synthesis of multifunctional gold nanoclusters for cell imaging, hydrogen sulfide detection and pH sensing | |
| Zhang et al. | High sensitivity and non-background SERS detection of endogenous hydrogen sulfide in living cells using core-shell nanoparticles | |
| Liu et al. | Penicillamine-protected Ag 20 nanoclusters and fluorescence chemosensing for trace detection of copper ions | |
| Sharma et al. | Synthesis of fluorescent molybdenum nanoclusters at ambient temperature and their application in biological imaging | |
| Liu et al. | Triggered peroxidase-like activity of Au decorated carbon dots for colorimetric monitoring of Hg 2+ enrichment in Chlorella vulgaris | |
| Samanta et al. | Synthesis of 3, 6-di (pyridin-2-yl)-1, 2, 4, 5-tetrazine (pytz) capped silver nanoparticles using 3, 6-di (pyridin-2-yl)-1, 4-dihydro-1, 2, 4, 5-tetrazine as reducing agent: Application in naked eye sensing of Cu2+, Ni2+ and Ag+ ions in aqueous solution and paper platform | |
| Mondal et al. | Colorimetric dual sensors of metal ions based on 1, 2, 3-triazole-4, 5-dicarboxylic acid-functionalized gold nanoparticles | |
| Sun et al. | Fluorescence sensing of cyanide anions based on Au-modified upconversion nanoassemblies | |
| Liu et al. | Glutathione modulated fluorescence quenching of sulfur quantum dots by Cu2O nanoparticles for sensitive assay | |
| Chen et al. | A redox reaction-induced ratiometric fluorescence platform for the specific detection of ascorbic acid based on Ag 2 S quantum dots and multifunctional CoOOH nanoflakes | |
| Jiang et al. | Inhibition to dual enzyme-like activities of Ag/CeO2 nanozymes for the detection of thiourea | |
| Wonjung et al. | Solid-phase colorimetric sensor for hypochlorite |
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 |