CN110357817B

CN110357817B - Reversible fluorescence probe for detecting methylglyoxal and glyoxal and preparation method and application thereof

Info

Publication number: CN110357817B
Application number: CN201910713163.7A
Authority: CN
Inventors: 楼开炎; 徐缓; 王卫; 马胜男; 刘倩倩
Original assignee: East China University of Science and Technology
Current assignee: East China University of Science and Technology
Priority date: 2019-08-02
Filing date: 2019-08-02
Publication date: 2022-07-26
Anticipated expiration: 2039-08-02
Also published as: CN110357817A

Abstract

The invention discloses a fluorescence probe for reversibly detecting methylglyoxal and glyoxal and a preparation method and application thereof, and the method comprises the steps of refluxing 4-bromo-1, 8-naphthalic anhydride and amine in ethanol for 3.5h to obtain N-R1-4-bromo-1, 8-naphthalimide, then stirring N-R1-4-bromo-1, 8-naphthalimide and guanidine at 100 ℃ in ethylene glycol monomethyl ether overnight under the protection of nitrogen to obtain a fluorescence probe compound for reversibly detecting methylglyoxal and glyoxal, taking 1, 8-naphthalimide as a fluorophore, and reacting guanidino with methylglyoxal and glyoxal to form reversible dihydroxy imidazolidine, so that the charge transfer effect in excited state molecules is increased, and strong fluorescence is generated. Therefore, the fluorescent probe can rapidly and reversibly detect the methylglyoxal and the glyoxal.

Description

Reversible fluorescence probe for detecting methylglyoxal and glyoxal and preparation method and application thereof

Technical Field

The invention relates to the technical field of organic synthesis and analytical chemistry, in particular to a reversible fluorescence probe for detecting methylglyoxal and glyoxal, a preparation method and application thereof.

Background

Reactive carbonyl compounds, such as formaldehyde, acetaldehyde, methylglyoxal, glyoxal, acrolein, and the like, play an important role in living systems. Because of the high reactivity of the compounds with deoxyribonucleic acid and protein, the active carbonyl compounds are related to the occurrence and development of other chronic diseases such as diabetes, cancer, obesity, Alzheimer disease, aging and the like. Wherein methylglyoxal and glyoxal, as active carbonyl compounds, are capable of inducing advanced glycosylation endproducts.

Methylglyoxal produces glycosylation end products mainly by reacting with lysine, arginine, cysteine residues, and this reaction process mainly affects different proteins such as insulin, hemoglobin and growth factors, and may also cause damage to DNA, resulting in cytotoxicity. It has been reported that the content of methylglyoxal in the serum of normal human body is 0.4-1.0. mu.M, while that in the serum of diabetic patients can reach 2.2-3.8. mu.M (analytical letters.2006,39(10): 2205-2215.). In order to be able to better understand the function of these reactive carbonyl compounds under physiological and pathological conditions, it is desirable to develop methods for selectively detecting and monitoring the level of reactive carbonyl compounds in biological samples. The detection of methylglyoxal is mostly based on the reaction of o-phenylenediamine with methylglyoxal to form stable groups, for example, HPLC, LC-MS, GC-MS are all used for detecting methylglyoxal based on this principle. However, these detection methods require cell lysis and are not suitable for use in complex living systems. Fluorescence detection has received much attention because it is simple, sensitive, and biocompatible, and can detect analytes in living systems.

So far, the fluorescence detection of methylglyoxal all uses o-phenylenediamine as a detection group, and generates fluorescence after irreversible reaction with methylglyoxal, and the method has defects in the aspects of selectivity, reaction speed and dynamic detection. Therefore, it is necessary and challenging to develop a new assay for methylglyoxal groups.

Disclosure of Invention

The invention takes 1, 8-naphthalimide as a fluorophore, forms reversible dihydroxy imidazolidine after guanidino reacts with methylglyoxal and glyoxal, and increases ICT effect, thereby generating strong fluorescence. Therefore, the fluorescent probe can rapidly and reversibly detect methylglyoxal and glyoxal.

To achieve the main object of the present invention, the present invention provides:

a fluorescent probe for reversibly detecting methylglyoxal and glyoxal, wherein the fluorescent probe has the following general formula I or II or III:

wherein R1 and R2 are both alkyl; n is a

natural number

1, 2 or 3.

Preferably, R1 and R2 are each independently methyl, ethyl or propyl.

Preferably, the formula I is the following formula I-1:

preferably, the formula II is the following formula II-1:

preferably, the formula III is of the following formula III-1:

the method for synthesizing the fluorescent probe shown in the general formula I comprises the following steps:

the method comprises the steps of refluxing 4-bromo-1, 8-naphthalic anhydride and amine in ethanol for 3.5 hours to obtain N-R1-4-bromo-1, 8-naphthalimide, and then stirring N-R1-4-bromo-1, 8-naphthalimide and guanidine at 100 ℃ under the protection of nitrogen overnight to obtain the reversible detection fluorescence probe compound for methylglyoxal and glyoxal.

Wherein the molar ratio of the 4-bromo-1, 8-naphthalic anhydride to the amine is 1:5 to obtain an intermediate N-R ¹ The molar ratio of the (E) -4-bromo-1, 8-naphthalimide to the guanidine is 1: 5.

The method for preparing the fluorescent probe shown in the general formula II is synthesized by the following route:

the method comprises the step of adding N-R under the protection of nitrogen ² Stirring (4-bromo-1, 8-naphthalimide) and methylguanidine at 100 ℃ for overnight to obtain reversible detection methylglyoxal and glyoxal fluorescent probe compounds, wherein N-R ² The molar ratio of the (E) -4-bromo-1, 8-naphthalimide to the methylguanidine is 1: 5.

The method for preparing the fluorescent probe shown in the general formula III is synthesized by the following route:

the method comprises the step of stirring a compound 1 and guanidine at ethylene glycol monomethyl ether at 100 ℃ overnight under the protection of nitrogen to obtain a reversible detection methylglyoxal and glyoxal fluorescent probe compound, wherein the molar ratio of the compound 1 to the guanidine is 1: 5. Preferably, the invention also discloses the application of the fluorescent probe prepared by the method in detecting methylglyoxal and glyoxal in a solution, a cell or an organism.

The fluorescence probe for reversibly detecting methylglyoxal and glyoxal disclosed by the invention has the advantages that after the probe is combined with methylglyoxal or glyoxal, the ICT effect is greatly increased, and the fluorescence intensity is increased. The recognition reaction is as follows:

a fluorescent probe: a class of fluorescent molecules that fluoresce characteristically in the uv-vis-nir region and whose fluorescent properties (excitation and emission wavelengths, intensity, lifetime, polarization, etc.) can change sensitively with changes in the properties of the environment, such as polarity, refractive index, viscosity, etc.; small molecule substances that interact non-covalently with nucleic acids (DNA or RNA), proteins or other macromolecular structures to alter one or more fluorescent properties. Can be used for researching the properties and behaviors of macromolecular substances.

Compared with the prior art, the invention has the following beneficial technical effects:

(1) the fluorescent probe for reversibly detecting the methylglyoxal and the glyoxal realizes the rapid reversible detection of the methylglyoxal and the glyoxal levels in cells and serum;

(2) the fluorescence probe provided by the invention has high sensitivity, can selectively and rapidly perform specific reaction with methylglyoxal and glyoxal to generate a product with strong fluorescence, and has higher selectivity and sensitivity on methylglyoxal and glyoxal compared with other common aldehydes, amino acids and metal ions;

(3) the reaction time is fast, and the reaction of the fluorescent probe, the methylglyoxal and the glyoxal can generate a product with strong fluorescence basically within 15min at room temperature;

(4) the probe has good optical stability and specific response to methylglyoxal and glyoxal, can be used for detecting the level of methylglyoxal and glyoxal in serum of a diabetes model animal, and has potential practical application value;

(5) the preparation advantages are obvious, the preparation method of the fluorescent probe is simple, and the yield is high.

Drawings

FIG. 1 is a nuclear magnetic resonance hydrogen spectrum of probe I-1;

FIG. 2 is a nuclear magnetic resonance hydrogen spectrum of probe II-1;

FIG. 3 is a nuclear magnetic resonance hydrogen spectrum of probe III-1;

FIG. 4 is a mass spectrum of probe I-1;

FIG. 5 is a mass spectrum of probe II-1;

FIG. 6 is a mass spectrum of probe III-1;

FIG. 7 is a graph showing the fluorescence of probe I-1 as a function of methylglyoxal concentration;

FIG. 8 is the fluorescence change of probe I-1 with different concentrations of glyoxal;

FIG. 9 is the change in fluorescence over time of the interaction of probe I-1 with methylglyoxal;

FIG. 10 shows the change in fluorescence with time upon the action of probe I-1 with glyoxal;

FIG. 11 shows the reversibility of the reaction of probe I-1 with methylglyoxal;

FIG. 12 shows the reversibility of the reaction of probe I-1 with glyoxal;

FIG. 13 is a selectivity study of probe I-1;

FIG. 14 shows fluorescence change of probe II-1 with varying concentrations of methylglyoxal;

FIG. 15 is a selectivity study of probe II-1;

FIG. 16 is a co-localized fluorescence imaging of probe I-1 with methylglyoxal and glyoxal.

Detailed Description

The present invention is further illustrated by the following specific examples, which are to be construed as merely illustrative, and not limitative of the remainder of the disclosure in any way whatsoever.

The starting materials and equipment used in the examples are well known to those skilled in the art and are either commercially available or readily available or manufactured.

Example 1

Synthesis of fluorescent Probe I-1:

4-bromo-1, 8-naphthalic anhydride (1.1g,4mmol) was suspended in 10mL of ethanol, n-propylamine (1.18g,20mmol) was added dropwise, and the reaction was heated under reflux for 3.5 h. The mixture was allowed to cool to room temperature, filtered, washed three times with ethanol and the filter cake was dried to give the product, N-propyl-4-bromo-1, 8-naphthalimide, as a pale yellow solid (1.02g, 80.5%). Under the protection of nitrogen, the compound N-propyl-4-bromo-1, 8-naphthalimide (382mg,1.2mmol) is suspended in 5mL of ethylene glycol methyl ether, guanidine (355mg,6mmol) is dissolved in 3mL of ethylene glycol methyl ether, and the ethylene glycol methyl ether solution of guanidine is slowly added dropwise to the suspension of N-propyl-4-bromo-1, 8-naphthalimide at room temperature. The reaction mixture was stirred at 100 ℃ overnight. Ethyl acetate and water were added to conduct extraction. The organic layer was dried over anhydrous sodium sulfate, filtered, spun-dried, and subjected to column chromatography (dichloromethane: methanol 10:1, vol.) to give compound I-1(138mg, 39%) as an orange-red solid.

The structural characterization of the NMR spectrum and the high-resolution mass spectrum of compound I-1 is shown in FIGS. 1 and 4. Wherein the nuclear magnetic resonance hydrogen spectrum data: ¹ HNMR(400MHz,DMSO-d ₆ )δ8.56(dd,J＝8.2,1.1Hz,1H),8.44(dd,J＝7.4,1.1Hz,1H),8.32(d,J＝8.2Hz,1H),7.72(dd,J＝8.2,7.4Hz,1H),7.33(d,J＝8.2Hz,1H),6.70(bs,4H),4.00(m,2H),1.63(h,J＝7.4Hz,2H),0.90(t,J＝7.4Hz,3H)；

high resolution mass spectrometry (ESI-HRMS) with m/z according to formula C ₁₆ H ₁₇ N ₄ O ₂ Calculated [ M + H] ⁺ The theoretical value of the peak is 297.1346 and 297.1353 is observed.

Example 2

Synthesis of fluorescent Probe II-1:

under the protection of nitrogen, the compound N-propyl-4-bromo-1, 8-naphthalimide (100mg,0.314mmol) is suspended in 1mL of ethylene glycol methyl ether, then the methylguanidine (115mg,1.57mmol) is dissolved in 1mL of ethylene glycol methyl ether, and the ethylene glycol methyl ether solution of the methylguanidine is slowly added dropwise to the suspension of N-propyl-4-bromo-1, 8-naphthalimide at room temperature. The reaction mixture was stirred at 100 ℃ overnight. Ethyl acetate and water were added to conduct extraction. The organic layer was dried over anhydrous sodium sulfate, filtered, spun-dried, and subjected to column chromatography (dichloromethane: methanol 10:1, vol.) to give compound II-1(27mg, 28%) as an orange-red solid.

The structural characterization of the nmr hydrogen spectrum and high resolution mass spectrum of compound II-1 is shown in fig. 2 and 5: ¹ HNMR(400MHz,DMSO-d ₆ )δ8.63(dd,J＝8.2,1.2Hz,1H),8.40(dd,J＝7.4,1.2Hz,1H),8.24(d,J＝8.3Hz,1H),7.62(dd,J＝8.2,7.4Hz,1H),7.08(d,J＝8.3Hz,1H),6.41(bs,1H),6.07(bs,2H),3.99(m,2H),2.82(s,3H),1.62(h,J＝7.4Hz,2H),0.90(t,J＝7.4Hz,3H)；

high resolution mass spectrometry (ESI-HRMS) with m/z according to formula C ₁₇ H ₁₉ N ₄ O ₂ Calculated [ M + H] ⁺ The theoretical value of the peak is 311.1503 and 311.1510 is found.

Example 3

Synthesis of fluorescent Probe III-1:

under the protection of nitrogen, compound a (947mg,2mmol) was suspended in 15mL of ethylene glycol methyl ether, guanidine (591mg,10mmol) was dissolved in 3mL of ethylene glycol methyl ether, and the ethylene glycol methyl ether solution of guanidine was added dropwise slowly to the suspension of a at room temperature. The reaction mixture was stirred at 100 ℃ overnight. Ethyl acetate and water were added to extract. The organic layer was dried over anhydrous sodium sulfate, filtered, spun-dried, and subjected to column chromatography (dichloromethane: methanol: triethylamine: 200:20:1) to give compound III-1(160mg, 18%) as an orange-red solid.

The structural characterization of compound III-1 is shown in fig. 3 and 6: ¹ HNMR(400MHz,DMSO-d ₆ )δ8.61(dd,J＝8.3,1.2Hz,1H),8.36(dd,J＝7.3,1.2Hz,1H),8.22(d,J＝8.3Hz,1H),7.72(bs,1H),7.64–7.59(m,3H),7.26(d,J＝8.1Hz,2H),7.12(d,J＝8.3Hz,1H),6.17(bs,4H),4.09(t,J＝6.7Hz,2H),3.03(bs,2H),2.28(s,3H)；

high resolution mass spectrometry (ESI-HRMS): m/z according to formula C ₂₂ H ₂₂ N ₅ O ₄ S calculated [ M + H] ⁺ The theoretical value of the peak is 452.1387 and 452.1393 is observed.

Example 4

Fluorescence spectrum change of reaction of fluorescent probe I-1 with methylglyoxal and glyoxal of different concentrations

The fluorescent probe I-1 prepared in example 1 was dissolved in dimethyl sulfoxide (DMSO) to prepare a fluorescent probe stock solution with a concentration of 1 mM; adding a methylglyoxal solution with the mass fraction of 40% into distilled water to prepare methylglyoxal mother liquor with the concentrations of 10mM and 100 mM; 8.8M glyoxal solution was added to distilled water to yield glyoxal stock solutions of 10M and 100M concentration. The required aqueous PBS solution (10mM, pH 7.4) was added to a 1cm × 1cm quartz cuvette (volume 3.5mL) based on the concentration of the fluorescent probe and methylglyoxal/glyoxal, 6 μ L of the fluorescent probe stock solution was added to the aqueous PBS solution, and then methylglyoxal/methylglyoxal stock solution (0-500 μ M) at different concentrations was added to prepare a total of 3mL of the test solution with a probe concentration of 2 μ M. After 30 minutes of reaction, the fluorescence spectrum change of the fluorescent probe I-1 reacted with methylglyoxal/glyoxal of different concentrations (excitation wavelength of 425nm) was measured by a fluorescence spectrometer. The fluorescence spectrum changes as shown in FIGS. 7 and 8. It can be seen that the fluorescence peak of the probe solution at 564nm gradually increased with increasing methylglyoxal/glyoxal concentration.

Example 5

Fluorescence spectrum change of reaction of fluorescent probe I-1 with methylglyoxal and glyoxal along with time change

The required aqueous PBS solution (10mM, pH 7.4) calculated from the concentration of the fluorescent probe and methylglyoxal/glyoxal was added to a 1cm × 1cm quartz cuvette (volume 3.5mL), and 6 μ L of the fluorescent probe mother liquor of example 1 was added to the aqueous PBS solution, and 60 μ L (10mM) of the methylglyoxal/glyoxal mother liquor was added to prepare a total of 3mL of test solution with a probe concentration of 2 μ M and a methylglyoxal/glyoxal concentration of 200 μ M. The change in the fluorescence spectrum with time was measured using 425nm as the excitation wavelength. As shown in FIGS. 9 and 10, the fluorescence peak at 564nm gradually increased with time.

Example 6

Reversibility of the fluorescent probe I-1 and methylglyoxal and glyoxal is studied.

The required aqueous PBS solution (10mM, pH 7.4) was added to a 1cm X1 cm quartz cuvette (volume 3.5mL) based on the fluorescent probe and the concentration of methylglyoxal/glyoxal, and 110mg of Aminoguanidine (AG) was added to the aqueous solution to prepare 10mM and 100mM stock solutions. mu.L of the fluorescent probe stock solution of example 1 was added to the PBS aqueous solution, 60. mu.L (10mM) of methylglyoxal/methylglyoxal stock solution was added to prepare a probe concentration of 2. mu.M, and 3mL of a test solution of aminoguanidine hydrochloride (150. mu.M-1 mM) was added thereto at different concentrations. Wherein aminoguanidine is used as an inhibitor. The fluorescence spectra were measured as a function of inhibitor concentration using 425nm as the excitation wavelength, as shown in FIGS. 11 and 12, and it was found that the fluorescence intensity at 564nm actually decreased with the addition of the inhibitor, regardless of whether the mother liquor was methylglyoxal or glyoxal, and the magnitude of the decrease increased with increasing inhibitor concentration.

Example 7

Selective study of Probe I-1 on different interfering analytes

The required aqueous PBS solution (10mM, pH 7.4) calculated from the concentration of the fluorescent probe and the different interfering analytes was added to a 1cm × 1cm quartz cuvette (volume 3.5mL), 6 μ L of the fluorescent probe stock from example 2 was added to the aqueous PBS solution, and 200 μ M of the different analytes were added: formaldehyde, salicylaldehyde, benzaldehyde, triphosgene, a nitric oxide donor NOC-18, pyruvaldehyde and glyoxal. A total of 3mL of test solution was prepared with a probe concentration of 2. mu.M and a different interfering analyte concentration of 200. mu.M, while leaving a blank test sample with only probe added. After 30 minutes of reaction, the fluorescence emission intensity at 564nm (excitation wavelength 425nm) of the different samples was measured with a fluorescence spectrometer. As shown in fig. 13, the fluorescence of the test solutions for methylglyoxal and glyoxal increased significantly relative to the blank test solution, while the fluorescence of the other analytes was not much enhanced. The experimental results show that the fluorescent probe I-1 has good selectivity on the methylglyoxal and the glyoxal.

EXAMPLE 8 fluorescence Spectroscopy Change of Probe II-1 with methylglyoxal at different concentrations

Dissolving the fluorescent probe II-1 prepared in example 2 in DMSO to prepare a fluorescent probe II mother liquor with a concentration of 1 mM; the required aqueous PBS solution (10mM, pH 7.4) calculated from the concentration of the fluorescent probe and methylglyoxal was added to a 1cm × 1cm quartz cuvette (volume 3.5mL), 6 μ L of the fluorescent probe stock solution was added to the aqueous PBS solution, and then methylglyoxal stock solution (0-1200 μ M) at different concentrations was added to prepare a total of 3mL of the test solution with a probe concentration of 2 μ M. After 30 minutes of reaction, the fluorescence spectrum change (excitation wavelength 391nm) of the reaction of the fluorescent probe II-1 and methylglyoxal with different concentrations was tested by a fluorescence spectrometer. The fluorescence spectrum changes as shown in FIG. 14. It can be seen that the peak fluorescence of the probe solution at 564nm gradually increased with increasing methylglyoxal concentration.

Example 8

Selective study of Probe II-1 on different interfering analytes

The required aqueous PBS solution (10mM, pH 7.4) calculated for the concentration of the fluorescent probe and different interfering analytes was added to a 1cm x 1cm quartz cuvette (volume 3.5mL), 6 μ L of the fluorescent probe stock from example 2 was added to the aqueous PBS solution, and 400 μ M of the different analytes were added: the test solution is prepared from formaldehyde, methylglyoxal, acetaldehyde, glyoxal, o-phthalaldehyde, glyoxylic acid, benzaldehyde, glutathione, glucose, cysteine, hydrogen peroxide, potassium ions, calcium ions, sodium ions, copper ions, zinc ions and aluminum ions, the concentration of the prepared probe is 2 mu M, the concentration of different interference analytes is 400 mu M, the total volume is 3mL, and a blank test sample only added with the probe is reserved. After 60 minutes of reaction, the fluorescence emission intensity at 564nm (excitation wavelength 391nm) of the different samples was measured by fluorescence spectrometer. As shown in fig. 15, the fluorescence of the test solutions for methylglyoxal and formaldehyde increased significantly relative to the blank test solution, while the fluorescence of the other analytes was not much enhanced. The experimental results show that the fluorescent probe II-1 has good selectivity for methylglyoxal and glyoxal.

Example 9

Co-localization fluorescence imaging of probe I-1 and methylglyoxal and glyoxal in HeLa cells

HeLa cells were seeded in T-25 cell culture flasks containing 10% fetal bovine serum and 1% glutamine in DMEM medium (containing phenol red, Gibco/Invitrogen) at 37 ℃ for 48 hours. The day before the experiment, cells were transferred to 3 Nunc35mm glass-bottom cell culture dishes (Thermoscientific) to allow cell adhesion. Probe I-1 was diluted in PBS buffer and added to the cell culture medium at a final concentration of 5. mu.M. After incubation in a cell incubator at 37 ℃ for 1 hour, the medium containing probe I-1 was removed. After washing twice with PBS buffer, cell culture medium containing 20 μ M methylglyoxal or glyoxal was added to the methylglyoxal and glyoxal petri dishes. Control (visit only)Needle petri dishes) were added the same amount of fresh medium. After incubation in a cell incubator at 37 ℃ for 30 minutes, the cells were placed in a cell culture chamber equipped with a 40 × objective lens and a photomultiplier gain of 800 (excitation and emission wavelength λ) _ex/em 405/530-590nm) was imaged on leica tcssp 8. After the first imaging step, 5mM acetylcysteine was added to the cell culture medium in the methylglyoxal and glyoxal petri dishes. The cells were then incubated in the cell incubator at 37 ℃ for another 30 minutes. At the end of the incubation, a 40 × objective lens was fitted and the photomultiplier gain was 800 (excitation and emission wavelength λ) _ex/em 405/530-590nm) was captured again on leica tcssp 8. As shown in fig. 16, the first group did not fluoresce, the second and fourth groups did fluoresce significantly, and the third and fifth groups were less fluorescent than the second and fifth groups. Experimental results show that the fluorescent probe I-1 can reversibly carry out fluorescence imaging on methylglyoxal and glyoxal in HeLa cells.

The above embodiments are merely preferred examples of the present invention, and not intended to limit the scope of the invention, so that equivalent changes or modifications in the structure, characteristics and principles of the invention described in the claims should be included in the claims.

Claims

1. A fluorescent probe for reversibly detecting methylglyoxal and glyoxal is characterized by having the following structure I-1 or II-1:

。

2. a method for preparing a fluorescent probe shown as a compound I, which is synthesized by the following route:

wherein R is ¹ -NH ₂ Is n-propylamine。

3. A method for preparing a fluorescent probe represented by compound II-1 of claim 1, which is synthesized by the following route:

。

4. the method of claim 2, comprising suspending 1.1g,4mmol of 4-bromo-1, 8-naphthalic anhydride in 10mL of ethanol, adding 1.18g,20mmol of n-propylamine dropwise, and reacting under reflux for 3.5 h; cooling to room temperature, filtering, washing with ethanol for three times, and drying a filter cake to obtain 1.02g of product N-propyl-4-bromo-1, 8-naphthalimide; under the protection of nitrogen, 382mg of 1.2mmol of compound N-propyl-4-bromo-1, 8-naphthalimide is suspended in 5mL of ethylene glycol methyl ether, then 355mg of 6mmol of guanidine is dissolved in 3mL of ethylene glycol methyl ether, and the ethylene glycol methyl ether solution of guanidine is slowly added dropwise into the suspension of N-propyl-4-bromo-1, 8-naphthalimide at room temperature; the reaction mixture was stirred at 100 ℃ overnight; adding ethyl acetate and water for extraction; drying the organic layer with anhydrous sodium sulfate, filtering, spin-drying, and performing column chromatography, wherein the eluent of the column chromatography is dichloromethane with the volume ratio of 10: 1: methanol to give 138mg of Compound I.

5. The method of claim 3, comprising suspending 100mg,0.314mmol of the compound N-propyl-4-bromo-1, 8-naphthalimide in 1mL of ethylene glycol monomethyl ether under nitrogen, dissolving 115mg,1.57mmol of methylguanidine in 1mL of ethylene glycol monomethyl ether, and slowly adding the solution of methylguanidine in ethylene glycol monomethyl ether to the suspension of N-propyl-4-bromo-1, 8-naphthalimide at room temperature; the reaction mixture was stirred at 100 ℃ overnight; adding ethyl acetate and water for extraction; drying the organic layer by using anhydrous sodium sulfate, filtering, spin-drying, and performing column chromatography, wherein the eluent of the column chromatography is dichloromethane with the volume ratio of 10: 1: methanol to obtain 27mg of compound II-1.

6. Use of the fluorescent probe of claim 1 in the preparation of a fluorescent probe for detecting methylglyoxal and glyoxal in a solution, cell or organism.