阅读说明：本技术 一种肝靶向零串扰比率检测硫化氢的荧光纳米探针及制备与应用 (Fluorescent nano probe for detecting hydrogen sulfide by liver-targeting zero-crosstalk ratio and preparation and application thereof ) 是由 曾荣今 魏宏庆 张培盛 张崇华 陈建 于 2019-08-29 设计创作，主要内容包括：本发明公开了一种肝靶向零串扰比率检测硫化氢的荧光纳米探针及制备与应用,该荧光纳米探针是以1-丙炔基-2-(((十二烷基硫代)硫代碳酰基)硫代)-2-甲基丙酸酯,苯乙烯(St),聚乙二醇甲醚(PEGMA),四乙酰基-a-D溴代半乳糖,叠氮化钠,四苯基卟啉,2,4-二硝基苯磺酰氯,9,9-二辛基聚芴-苯并噻二唑交替共聚物等为原料制备的一种新型比率荧光纳米探针。该荧光纳米探针能在纯水溶液中能实现硫化氢的高选择性和高灵敏度比率检测,能够对硫化氢进行高选择性零串扰比率检测,并且该探针的端基半乳糖功能化,具有肝靶向的功能,且有着低细胞毒性,优良的水分散性,较大的Stokes位移等优点,在分析化学、生命科学、以及环境科学等技术领域有着巨大的应用前景。(The invention discloses a fluorescent nano probe for detecting hydrogen sulfide by a liver-targeting zero-crosstalk ratio, and preparation and application thereof, wherein the fluorescent nano probe is a novel ratiometric fluorescent nano probe prepared by taking 1-propynyl-2- (((dodecylthio) thiocarbonyl) thio) -2-methylpropionate, styrene (St), polyethylene glycol methyl ether (PEGMA), tetraacetyl-a-D (bromogalactose), sodium azide, tetraphenylporphyrin, 2, 4-dinitrobenzenesulfonyl chloride, 9, 9-dioctyl polyfluorene-benzothiadiazole alternating copolymer and the like as raw materials. The fluorescent nano probe can realize high-selectivity and high-sensitivity ratio detection of hydrogen sulfide in a pure water solution, can perform high-selectivity zero-crosstalk ratio detection on the hydrogen sulfide, has the functions of liver targeting due to the functionalization of the terminal galactose of the probe, has the advantages of low cytotoxicity, excellent water dispersibility, larger Stokes displacement and the like, and has great application prospects in the technical fields of analytical chemistry, life science, environmental science and the like.)

1. The fluorescent nano probe for detecting hydrogen sulfide by using liver-targeted zero crosstalk ratio is characterized by being formed by self-assembling an amphiphilic block copolymer, a fluorescent molecule containing porphyrin and a 9, 9-dioctyl polyfluorene-benzothiadiazole alternating copolymer in water, wherein the structural formula of the amphiphilic block copolymer is as follows:

wherein x/y/n/z is 1: 10-30: 5-15: 70 to 130, R₁Is C₇-C₁₇One of (1) n-alkyl.

2. A preparation method of a fluorescent nano probe for detecting hydrogen sulfide by a liver-targeted zero-crosstalk ratio is characterized by comprising the following steps of:

dissolving a certain amount of 1-propynyl-2- (((dodecylthio) thiocarbonyl) thio) -2-methylpropionate, polyethylene glycol methyl ether PEGMA, 2-aminoethyl methacrylate ester hydrochloride acid and azobisisobutyronitrile AIBN in dimethyl formamide DMF, performing vacuum-nitrogen filling circulation for three times, then quickly heating to 70 ℃ for reaction for 4 hours, precipitating with diethyl ether after the reaction is finished, and performing vacuum drying to obtain a product 1;

dissolving a certain amount of the product 1, styrene and azobisisobutyronitrile AIBN in 1mL of dimethyl formamide DMF, performing vacuum-nitrogen filling circulation for three times, rapidly heating to 80-100 ℃ for reaction for 24 hours, precipitating with diethyl ether/petroleum ether 1:1 after the reaction is finished, and performing vacuum drying to obtain a product 2;

dissolving a certain amount of tetraacetyl-a-D bromogalactose and sodium azide in 5mL of dimethyl sulfoxide DMSO, reacting at normal temperature for 30min, adding 2mL of distilled water to quench the reaction after the reaction is finished, extracting with ethyl acetate, removing the organic solvent by rotary evaporation, and drying in vacuum to obtain a product 3;

step (4), adding a certain amount of the product 3 and sodium methoxide into 12mL of methanol, stirring at room temperature for 24h, adding a cation exchange resin IR120 sodium type after the reaction is finished, adjusting the pH to 7, filtering to remove insoluble substances, removing the organic solvent by rotary evaporation, and drying in vacuum to obtain a product 4;

step (5), dissolving a certain amount of the product 2 and the product 4, namely sodium ascorbate and copper sulfate pentahydrate, in a solution of water/tetrahydrofuran 5:1(v/v), stirring for 24 hours at normal temperature, and extracting with dichloromethane to obtain a product 5, namely an amphiphilic block copolymer;

and (6) preparing the amphiphilic block copolymer synthesized in the step (5) into a tetrahydrofuran THF solution A with a certain concentration, preparing a tetrahydrofuran solution B with a certain concentration by using fluorescent molecules containing porphyrin, preparing a tetrahydrofuran solution C with a certain concentration by using a 9, 9-dioctyl polyfluorene-benzothiadiazole alternating copolymer, mixing a certain amount of A, B, C solutions respectively, adding A, B, C molar ratio into 10mL of water under an ultrasonic condition, continuing to perform ultrasonic treatment for 10min after dropwise addition is completed, removing tetrahydrofuran under reduced pressure at room temperature, and fixing the volume to 10mL by using distilled water to obtain the required fluorescence sensor, thus obtaining the fluorescence nano probe for detecting hydrogen sulfide by using the liver targeting zero crosstalk ratio.

3. The preparation method of the fluorescent nanoprobe for detecting hydrogen sulfide with liver-targeted zero crosstalk ratio according to claim 2, characterized in that: in the step (1), the molar ratio of 1-propynyl-2- (((dodecylthio) thiocarbonyl) thio) -2-methylpropionate to polyethylene glycol methyl ether PEGMA to 2-aminoethyl methacrylate ester acid to azobisisobutyronitrile AIBN is 10: 150-300: 15-45: 0.5-1.5; wherein the concentration of the 1-propynyl-2- (((dodecylthio) thiocarbonyl) thio) -2-methylpropionate in DMF is 0.05 mmol/L-0.15 mmol/mL.

4. The preparation method of the fluorescent nanoprobe for detecting hydrogen sulfide with liver-targeted zero crosstalk ratio according to claim 2, characterized in that: the molar ratio of the product 1, the styrene and the azobisisobutyronitrile AIBN in the step (2) is 10: 3000-7000: 4-8, wherein the concentration of the product 1 in DMF is 0.005 mmol/mL-0.015 mmol/mL.

5. The preparation method of the fluorescent nanoprobe for detecting hydrogen sulfide with liver-targeted zero crosstalk ratio according to claim 2, characterized in that: the molar ratio of the tetraacetyl-a-D bromogalactose to the sodium azide in the step (3) is 1: 3-7, wherein the concentration of the tetraacetyl-a-D bromogalactose in the DMSO is 0.17 mmol/L-0.26 mmol/L.

6. The preparation method of the fluorescent nanoprobe for detecting hydrogen sulfide with liver-targeted zero crosstalk ratio according to claim 2, characterized in that: the molar ratio of the product 3 in the step (4) to sodium methoxide is 1: 4-8, wherein the concentration of the product 3 in methanol is 0.065 mmol/mL-1.125 mmol/mL.

7. The preparation method of the fluorescent nanoprobe for detecting hydrogen sulfide with liver-targeted zero crosstalk ratio according to claim 2, characterized in that: the molar ratio of the product 2 to the product 4 in the step (5), sodium ascorbate and copper sulfate pentahydrate is 1: 50-150: 10-20: 5-9, wherein the concentration of the product 2 in water/tetrahydrofuran 5:1(v/v) is 0.001 mmol/mL-0.002 mmol/mL.

8. The preparation method of the fluorescent nanoprobe for detecting hydrogen sulfide with liver-targeted zero crosstalk ratio according to claim 2, characterized in that: the mass ratio of A, B, C in the step (6) is 80: 20-30: 10 to 20, wherein the concentration of the amphiphilic block copolymer in water is 0.6 to 1.0 mg/mL.

9. The fluorescent nanoprobe for detecting hydrogen sulfide with liver-targeting zero crosstalk ratio as claimed in claim 1 or the fluorescent nanoprobe for detecting hydrogen sulfide with liver-targeting zero crosstalk ratio as prepared by the preparation method as claimed in any one of claims 2 to 8 is applied to detection of hydrogen sulfide in liver cells.

Technical Field

The invention belongs to the field of chemical material preparation and analysis and detection, and relates to preparation and application of a fluorescent nano probe for detecting hydrogen sulfide at a comparable rate, in particular to a fluorescent nano probe for detecting hydrogen sulfide at a liver-targeted zero-crosstalk ratio, and preparation and application thereof.

Background

Hydrogen sulfide (H)₂S) is a colorless, easily water-soluble combustible gas with a smelly egg smell. H₂S can be ionized in aqueous solution and has H₂S、HS^-And S^2-Three existing forms exist, and the existing forms are directly related to the pH value of the solution. Hydrogen sulfide is an important neurotransmitter molecule in human bodies, a molecule for regulating cardiovascular functions, an inflammation regulating factor, an endothelial derived vasodilating factor and the like, and plays an important role in human physiological and pathological regulation mechanisms. However, abnormality of the concentration level can cause many human diseases, so that the recognition and detection of hydrogen sulfide in the organism are of great significance for the diagnosis and treatment of diseases. At present, there are many methods for detecting hydrogen sulfide, such as ultraviolet absorption method, electrochemical method, chromatography, etc., however, compared with complex and expensive instruments and reagents, the fluorescence probe method has received much attention due to its advantages of high analysis sensitivity, simple operation, small sample usage, low detection cost, good selectivity, and capability of performing fluorescence imaging on physiologically active cells.

The probes reported at present are mainly single-emission wavelength small molecule probes, such as (CN104945407A, CN 105295900A). The fluorescent probe based on single emission wavelength is used for on-inspectionThe interference of background, concentration and light source in the measuring process is large, so that the sensitivity is low, and the misjudgment rate is high. Moreover, these fluorescent probes are mainly based on small molecules, and the water solubility and potential biological toxicity of the fluorescent probes greatly limit the applications in the biological and medical fields. Compared with a single-wavelength fluorescent probe, the ratio type fluorescent probe improves the dynamic response range by establishing an internal standard and utilizing the change of the fluorescence intensity ratio of two wavelengths, thereby greatly avoiding the interference of a plurality of variable factors such as probe concentration, temperature, polarity, environmental pH value, stability and the like. However, most rate-type fluorescent probes have the disadvantage of spectral crosstalk, which will seriously interfere with their detection in the field of biological imaging, while fluorescent probes with zero-crosstalk spectral characteristics have no interference between two emission peaks during imaging due to large displacement between the two emission peaks and almost no spectral overlap. In addition, compared with the traditional micromolecule fluorescent probe with complex synthesis and poor water solubility, the fluorescent nano probe taking the amphiphilic block polymer as the carrier shows extremely wide application prospect in the research fields of chemistry, medicine, environmental science and the like due to the advantages of excellent water solubility, low cytotoxicity, no organic solvent residue, strong designability, high sensitivity, high selectivity and the like, and the liver is the in vivo H₂The major site of S production, probably for H maintenance in circulating blood₂The concentration of S plays an important role, so that the design of a fluorescent nano probe with liver targeting function and zero crosstalk ratio for detecting hydrogen sulfide is very necessary.

The present invention has been made in view of this situation.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provides a fluorescent nano probe for detecting hydrogen sulfide by a liver-targeting zero-crosstalk ratio and preparation and application thereof, wherein the fluorescent nano probe is further applied and researched by 1-propynyl-2- (((dodecylthio) thiocarbonyl) thio) -2-methylpropionate, styrene (St), polyethylene glycol methyl ether (PEGMA), tetraacetyl-a-D (bromogalactose), sodium azide, tetraphenylporphyrin and 2, 4-dinitrobenzenesulfonyl chloride to show that the fluorescent nano probe can realize high-sensitivity and high-selectivity rapid ratio detection of hydrogen sulfide.

In order to solve the technical problems, the invention adopts the technical scheme that:

a fluorescent nano probe for detecting hydrogen sulfide by a liver-targeting zero-crosstalk ratio is formed by self-assembling an amphiphilic block copolymer, a fluorescent molecule containing porphyrin and a 9, 9-dioctyl polyfluorene-benzothiadiazole alternating copolymer in water.

Wherein the amphiphilic block copolymer has the structural formula:

wherein n/x/y/z is 1: 2-4: 1.5-2: 10 to 15, R₁Is C₇-C₁₇One of (1) n-alkyl.

The amphiphilic block copolymer consists of a hydrophilic section of polyethylene glycol methyl ether, 2-aminoethyl methacrylate ester acid and a hydrophobic section of styrene, and a galactose structure with a liver targeting function is positioned at the leftmost end of the hydrophilic section, so that the amphiphilic block copolymer can play a good liver targeting role in a fluorescent nano probe for detecting hydrogen sulfide at a zero crosstalk ratio.

In the fluorescent nano probe for detecting hydrogen sulfide by liver-targeted zero-crosstalk ratio, the preparation of amphiphilic block copolymer comprises the following steps:

(1) dissolving a certain amount of 1-propynyl-2- (((dodecylthio) thiocarbonyl) thio) -2-methylpropionate, polyethylene glycol methyl ether PEGMA, 2-aminoethyl methacrylate ester hydrochloride and azobisisobutyronitrile AIBN in dimethyl formamide DMF, vacuumizing and filling nitrogen for three times, quickly heating to 70 ℃ for reaction for 4 hours, precipitating by using diethyl ether after the reaction is finished, and drying in vacuum to obtain a product 1;

(2) dissolving a certain amount of product 1, styrene and azobisisobutyronitrile AIBN in 1mL of dimethylformamide DMF, performing vacuum-nitrogen filling circulation for three times, then rapidly heating to 80-100 ℃ for reaction for 24 hours, precipitating with diethyl ether/petroleum ether 1:1 after the reaction is finished, and performing vacuum drying to obtain a product 2;

(3) dissolving a certain amount of tetraacetyl-a-D bromogalactose and sodium azide in 5mL of dimethyl sulfoxide DMSO, reacting at normal temperature for 30min, adding 2mL of distilled water to quench the reaction after the reaction is finished, extracting with ethyl acetate, removing the organic solvent by rotary evaporation, and drying in vacuum to obtain a product 3;

(4) adding a certain amount of the product 3 and sodium methoxide into 12mL of methanol, stirring at room temperature for 24h, adding a cation exchange resin IR120 sodium type after the reaction is finished, adjusting the pH to 7, filtering to remove insoluble substances, removing the organic solvent by rotary evaporation, and drying in vacuum to obtain a product 4;

(5) dissolving a certain amount of the product 2 and the product 4, sodium ascorbate and copper sulfate pentahydrate in a solution of water/tetrahydrofuran 5:1(v/v), stirring at normal temperature for 24h, and extracting with dichloromethane to obtain a product 5, namely an amphiphilic block copolymer;

the amphiphilic block copolymer prepared by the preparation method is characterized in that in the step (1), the molar ratio of 1-propynyl-2- (((dodecylthio) thiocarbonyl) thio) -2-methylpropionate to polyethylene glycol methyl ether (PEGMA), 2-aminoethyl methacrylate ester acid to Azobisisobutyronitrile (AIBN) is 10: 150-300: 15-45: 0.5-1.5, and the concentration of 1-propynyl-2- (((dodecylthio) thiocarbonyl) thio) -2-methylpropionate in DMF is 0.05 mmol/mL-0.15 mmol/mL; the molar ratio of the product 1, styrene and Azobisisobutyronitrile (AIBN) in the step (2) is 10: 3000-7000: 4-8, wherein the concentration of the product 1 in DMF is 0.005-0.015 mmol/mL; the molar ratio of the tetraacetyl-a-D bromogalactose to the sodium azide in the step (3) is 1: 3-7, wherein the concentration of the tetraacetyl-a-D bromogalactose in the DMSO is 0.17-0.26 mmol/mL; the molar ratio of the product 3 in the step (4) to sodium methoxide is 1: 4-8, wherein the concentration of the product 3 in methanol is 0.065-1.125 mmol/mL; in the step (5), the molar ratio of the product 2 to the product 4 to the sodium ascorbate to the copper sulfate pentahydrate is 1: 50-150: 10-20: 5-9, wherein the concentration of the product 2 in a solution of water/tetrahydrofuran 5:1 is 0.001-0.002 mmol/mL.

The amphiphilic block copolymer prepared according to the above preparation method has a specific reaction process as follows

Wherein the structural formula of the porphyrin-containing fluorescent molecule (5, 10-bis (4- (2, 4-dinitrobenzene sulfonate)) 15, 20-diphenylporphyrin) is as follows:

in a fluorescent nanoprobe for detecting hydrogen sulfide by a liver-targeted zero-crosstalk ratio, the preparation of a porphyrin-containing fluorescent molecule (5, 10-bis (4- (2, 4-dinitrobenzene sulfonate)) 15, 20-diphenylporphyrin) comprises the following steps:

(1) dissolving a certain amount of tetraphenylporphyrin in trifluoroacetic acid (TFA), and rapidly adding a certain amount of NaNO₂Reacting at room temperature for 90s, quickly adding water to quench the reaction, adjusting the pH of the reaction solution to 8 by using ammonia water, cooling, extracting by using dichloromethane, removing the solvent by rotary evaporation, dissolving the product by using concentrated hydrochloric acid, adding a certain amount of stannous chloride, carrying out reflux reaction at 90 ℃ for 12h, and adding ammonia water to adjust the pH to 8 after the reaction solution is cooled. Extracting with ethyl acetate, rotary evaporating, and purifying with column to obtain 5, 10-bis (4-aminophenyl) -15, 20-diphenylporphyrin.

(2) Dissolving a certain amount of 5, 10-di (4-aminophenyl) -15, 20-diphenylporphyrin in a solution of glacial acetic acid and concentrated phosphoric acid at a volume ratio of 1:1, and adding NaNO dissolved in concentrated sulfuric acid₂And (3) reacting the solution at 0 ℃ for 2h, adding the reaction solution into a 50% sulfuric acid solution, carrying out reflux reaction at 95 ℃ for 12h, cooling the reaction solution, and adding NaOH to adjust the pH value to 8. Extracting with ethyl acetate, rotary evaporating, and separating and purifying 5, 10-di (4-hydroxyphenyl) -15, 20-diphenyl porphyrin by column.

(3) Dissolving a certain amount of 5, 10-bis (4-hydroxyphenyl) -15, 20-diphenylporphyrin, 2, 4-dinitrobenzenesulfonyl chloride in Dichloromethane (DCM): adding a certain amount of triethylamine into Tetrahydrofuran (THF)3:1, reacting at room temperature for 24h, removing solvent by rotary evaporation after the reaction is finished, separating and purifying the product by a column, and drying in vacuum to obtain the product porphyrin-containing fluorescent molecule (5, 10-bis (4- (2, 4-dinitrobenzene sulfonate)) 15, 20-diphenylporphyrin), a kind of fluorescent moleculeCan detect H₂Small molecule organic compounds of S.

The small-molecule organic compound prepared by the preparation method is characterized in that in the step (1), tetraphenylporphyrin and NaNO are added₂The molar ratio of (1: 6.5) - (10.5), and the concentration of tetraphenylporphyrin in trifluoroacetic acid is 0.003-0.009 mmol/mL; in the step (2), 5, 10-bis (4-aminophenyl) -15, 20-diphenylporphyrin, NaNO₂The molar ratio of the 5, 10-bis (4-aminophenyl) -15, 20-diphenylporphyrin to the concentrated phosphoric acid is 1:1, wherein the concentration of the 5, 10-bis (4-aminophenyl) -15, 20-diphenylporphyrin in the solution is 0.196 mmol/mL; in the step (3), the molar ratio of the 5, 10-bis (4-hydroxyphenyl) -15, 20-diphenylporphyrin to the 2, 4-dinitrobenzenesulfonyl chloride to the triethylamine is 1: 5-15, wherein the concentration of the 5, 10-bis (4-hydroxyphenyl) -15, 20-diphenylporphyrin in DCM is 0.025 mmol/mL-0.045 mmol/mL.

The specific reaction process of the porphyrin-containing fluorescent molecule (5, 10-bis (4- (2, 4-dinitrobenzene sulfonate)) 15, 20-diphenylporphyrin) prepared according to the preparation method is as follows:

the structural formula of the 9, 9-dioctyl polyfluorene-benzothiadiazole alternating copolymer is as follows:

the conjugated polymer has excellent light stability and no response to hydrogen sulfide, and is a good reference group in the fluorescent nano probe for detecting hydrogen sulfide by liver-targeted zero crosstalk ratio because the excitation spectrum overlaps with the fluorescent molecule containing porphyrin, the emission spectrum peak difference of the excitation spectrum and the fluorescent molecule can be 126nm besides co-excitation, and no spectrum overlap exists.

The invention provides an application of a fluorescent nano probe for detecting hydrogen sulfide by a liver-targeting zero-crosstalk ratio in detecting hydrogen sulfide in liver cells.

The preparation method of the fluorescent nano probe for detecting hydrogen sulfide at a comparable rate comprises the following steps: preparing an amphiphilic block copolymer into a Tetrahydrofuran (THF) solution A with a certain concentration and a fluorescent molecule containing porphyrin into a Tetrahydrofuran (THF) solution B with a certain concentration and a 9, 9-dioctyl polyfluorene-benzothiadiazole alternating copolymer into a Tetrahydrofuran (THF) solution C with a certain concentration, then respectively mixing A, B, C, adding into 10mL of water under an ultrasonic condition, continuing to perform ultrasonic treatment for 10min after dropwise addition is completed, then removing THF under reduced pressure at room temperature, and fixing the volume to 10mL with water to obtain the required fluorescent nano probe, namely the fluorescent nano probe for detecting hydrogen sulfide by using a liver-targeted zero crosstalk ratio.

After the technical scheme is adopted, compared with the prior art, the invention has the following beneficial effects.

The invention takes 1-propynyl-2- (((dodecylthio) thiocarbonyl) thio) -2-methylpropionate, styrene (St), polyethylene glycol methyl ether (PEGMA), tetraacetyl-a-D bromogalactose, sodium azide, tetraphenylporphyrin and 2, 4-dinitrobenzene sulfonyl chloride as raw materials to prepare the required fluorescent nano probe, and the fluorescent nano probe is in a buffer solution with the pH value of 7.4 and in the presence of H₂When S exists, 659nm will follow H₂The concentration of S increases to show a remarkable fluorescence enhancement phenomenon, and the fluorescence at 533nm is along with H₂The increase in S concentration did not change significantly. The fluorescent nano probe response group has the advantages that the fluorescent wavelength in the near infrared region can reduce the self-fluorescence interference of organisms when applied to cell imaging, the fluorescent nano probe has obvious high selectivity for detecting hydrogen sulfide, the effect of high-sensitivity detection can be achieved, and the Storks displacement is small. Compared with the existing detection technologies, the fluorescent chemical probe has the advantages of low cost investment, simple synthetic route, convenient post-treatment and capability of directly realizing rapid specific recognition on hydrogen sulfide.

In summary, the invention provides a preparation method and an application of a fluorescent nano probe for detecting hydrogen sulfide by a liver-targeting zero-crosstalk ratio.

The following describes embodiments of the present invention in further detail with reference to the accompanying drawings.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the invention and together with the description serve to explain the invention without limiting the invention to its proper form. It is obvious that the drawings in the following description are only some embodiments, and that for a person skilled in the art, other drawings can be derived from them without inventive effort. In the drawings:

FIG. 1 is a particle size diagram of the prepared fluorescent nanoprobe.

FIG. 2 is a schematic diagram of hydrogen sulfide identification by the prepared fluorescent nanoprobe.

FIG. 3 shows a difference H₂(S concentration, H) the fluorescence emission spectrum change pattern of the fluorescent nanoprobe (excitation wavelength: 440nm)₂S]＝0(a)，1.0×10^-2mol/L(b),1.8×10^-2mol/L(c),2.6×10^-2mol/L(d)，3.8×10^-2mol/L(e)，6.6×10^-2mol/L(f),7.6×10^-2mol/L(g),8.6×10^-2mol/L(h)，10.6×10^-2mol/L(i),12.6×10^-1mol/L(j),14.6×10^-1mol/L(k),16.6×10^-1mol/L(l),18.6×10^-1mol/L(m),20.6×10^-1mol/L(n),22.6×10^-1mol/L(o),24.6×10^-1mol/L(p),26.6×10^-1mol/L(q),28.6×10^-1mol/L(r),30.6×10^-1mol/L(s),32.6×10^-1mol/L(t)。

FIG. 4 shows fluorescent nanoprobes with H₂And a fitted curve corresponding to the fluorescence intensity change value with the change of the S concentration and a function graph corresponding to the curve.

FIG. 5 is a graph of data showing the selective comparison of the fluorescence ratio intensity of various ions to the fluorescent nanoprobe, wherein the concentration of the added ions is 2.0 × 10^-3mol/L，H₂The S concentration is 2.0 × 10^-4mol/L，I₆₅₉And I₅₃₃The fluorescence intensity change values of the fluorescent nano-probe before and after the addition of each ion and peroxide at the excitation wavelength of 440nm and the emission wavelengths of 659nm and 533 nm.

FIG. 6 is a graph of interference contrast data of fluorescence ratio intensity of various ions to fluorescent nanoprobes, wherein the concentration of various ions added is 2.0 × 10^-3mol/L，H₂The S concentration is 2.0 × 10^-4mol/L，I₆₅₉And I₅₃₃The fluorescence intensity change values of the fluorescent nano-probe before and after the addition of each ion and peroxide at the excitation wavelength of 440nm and the emission wavelengths of 659nm and 533 nm.

It should be noted that the drawings and the description are not intended to limit the scope of the inventive concept in any way, but to illustrate it by a person skilled in the art with reference to specific embodiments.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and the following embodiments are used for illustrating the present invention and are not intended to limit the scope of the present invention.