Formaldehyde fluorescent probe compound, preparation method and application thereof

Abstract

The present invention relates to the technical field of formaldehyde fluorescent probe molecules, and in particular, to formaldehyde fluorescent probe compounds, preparation methods and applications thereof. The formaldehyde fluorescent probe compound is selected from any one of the compounds shown in the following structural formula: #imgabs0# wherein X is a halogen, and R1 is selected from any one of a substituted or unsubstituted alkyl group, a substituted or unsubstituted alcohol group, a substituted or unsubstituted carboxyl group and a substituted or unsubstituted sulfonic acid group. The formaldehyde fluorescent probe compound has near-infrared emission fluorescence, and its fluorescence changes significantly after reacting with formaldehyde, accompanied by an obvious color change from yellow to dark green. The formaldehyde fluorescent probe compound has two steps for synthesis, has low cost, has the advantages of immediate response to formaldehyde, good anti-interference ability, low detection limit and naked eye recognition, and is helpful to achieve rapid detection of formaldehyde in food.

Description

Technical Field

[0001] The present invention relates to the technical field of formaldehyde fluorescent probe molecules, and in particular to a formaldehyde fluorescent probe compound, a preparation method thereof and an application thereof. Background Art

[0002] At present, food safety issues have received widespread attention. Discovering harmful substances in food is the primary condition for food supervision. Adding formaldehyde to food can achieve the effect of preservation and whitening, such as adding formalin to aquatic products and adding bleaching powder to food. Some foods contain or metabolize formaldehyde, such as mushrooms and frozen fish. Due to the volatility and irritation of formaldehyde, it can cause great damage to human skin, respiratory tract and liver system, endangering human health. Therefore, the rapid quantitative detection of formaldehyde in food is of great significance.

[0003] The determination of formaldehyde in food usually adopts the pretreatment method of extraction and derivatization, and then adopts spectrophotometry, liquid chromatography or fluorescence method for quantification. However, the disadvantages of these methods are that the instruments are expensive and the pretreatment procedures are complicated. Fluorescent probe technology has the advantages of specificity and high sensitivity, and has played an important role in the fields of environment, biochemistry and medicine. Summary of the invention

[0004] The object of the present invention is to provide a formaldehyde fluorescent probe compound, a preparation method thereof and an application thereof. The formaldehyde fluorescent probe compound provided in the embodiment of the present invention has good fluorescence specificity and high selectivity, can effectively improve the detection sensitivity of fluorescence spectrophotometry, and at the same time, because the probe molecule has an obvious color change after binding to formaldehyde, it has the advantage of naked eye recognition, and can realize the rapid detection of formaldehyde in food. And the formaldehyde fluorescent probe compound has good chemical stability and light stability, the synthesis steps are simple, and the cost is low.

[0005] The present invention is achieved in that:

[0006] In a first aspect, the present invention provides a formaldehyde fluorescent probe compound for detecting formaldehyde, which is selected from any one of the compounds represented by the following structural formulas:

[0007]

[0008] Wherein, X is a halogen, and R1 is selected from any one of a substituted or unsubstituted alkyl group, a substituted or unsubstituted alcohol group, a substituted or unsubstituted carboxyl group, and a substituted or unsubstituted sulfonic acid group.

[0009] In an alternative embodiment, X is selected from bromine or iodine, preferably iodine.

[0010] In an optional embodiment, R1 is selected from any one of a C1-C5 unsubstituted alkyl group, a C2-C6 substituted hydroxyl group, a C3-C5 unsubstituted carboxyl group, and a C2-C5 substituted sulfonic acid group;

[0011] Preferably, R1 is selected from any one of a methyl group, a hydroxyethyl group, a propionic acid group and a propanesulfonic acid group.

[0012] In an optional embodiment, it is selected from any one of the compounds represented by the following structural formulas:

[0013]

[0014] In a second aspect, the present invention provides a method for preparing the formaldehyde fluorescent probe compound described in the aforementioned embodiment, comprising synthesizing the formaldehyde fluorescent probe compound according to the following synthesis path:

[0015] Synthesis route 1:

[0016]

[0017] Synthesis Path 2:

[0018]

[0019] Wherein, X is a halogen, and R1 is selected from any one of a substituted or unsubstituted alkyl group, a substituted or unsubstituted alcohol group, a substituted or unsubstituted carboxyl group, and a substituted or unsubstituted sulfonic acid group.

[0020] In an optional embodiment, in synthetic route 1:

[0021] Step 1: mixing an indole compound, an aldehyde compound, a first solvent and an organic base to react to form an intermediate;

[0022] Preferably, the molar ratio of the indole compound to the aldehyde compound is 2.0-2.2:1, the reaction temperature is 80-85°C, and the reaction time is 8-12 hours;

[0023] Preferably, in synthetic route 1:

[0024] Step 2: mixing the intermediate, hydrazine hydrate, a catalyst and a second solvent to react;

[0025] Preferably, the molar ratio of the intermediate to the hydrazine hydrate is 1:1, the reaction temperature is -10-0°C, and the reaction time is 0.5-1.0 hour.

[0026] In an optional embodiment, in synthetic route 2:

[0027] Step 1: mixing two indole compounds, an aldehyde compound, a first solvent and an organic base to react to form an intermediate;

[0028] Preferably, the molar ratio of the two indole compounds to the aldehyde compound is 2:1, the reaction temperature is 80-85° C., and the reaction time is 8-12 hours;

[0029] Step 2: mixing the intermediate, hydrazine hydrate, a catalyst and a second solvent to react;

[0030] Preferably, the molar ratio of the intermediate to the hydrazine hydrate is 1:1, the reaction temperature is -10-0°C, and the reaction time is 0.5-1.0 hour.

[0031] In a third aspect, the present invention provides a use of the formaldehyde fluorescent probe compound described in the aforementioned embodiment in detecting formaldehyde.

[0032] Preferably, the application comprises application in the detection of food.

[0033] In a fourth aspect, the present invention provides a formaldehyde spectrochemical sensor, which is prepared using the formaldehyde fluorescent probe compound described in the aforementioned embodiment.

[0034] In a fifth aspect, the present invention provides a method for detecting formaldehyde, which uses the formaldehyde fluorescent probe compound described in the aforementioned embodiment or the formaldehyde spectrochemical sensor described in the aforementioned embodiment for detection.

[0035] The present invention has the following beneficial effects: 1) The formaldehyde fluorescent probe compound of the present invention has good fluorescence specificity and high selectivity, and exhibits good anti-interference performance to other metal and non-metal ions. Its rapid spectral response and low detection limit make it possible to be used in food detection.

[0036] 2) It has good chemical stability and good light stability, and the synthesis steps are simple and the cost is low. The formaldehyde fluorescent probe molecule has an obvious color change after binding to formaldehyde, has the advantage of naked eye recognition, can realize the rapid detection of formaldehyde in food, and can effectively improve the detection sensitivity of fluorescence spectrophotometry. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0038] Figure 1The color change diagram of the formaldehyde fluorescent probe compound of Example 2 provided in Detection Example 1 of the present invention before (left) and after (right) the addition of formaldehyde under room temperature sunlight;

[0039] Figure 2 This is a diagram of the molecular “on-off” mechanism of the formaldehyde fluorescent probe compound of Example 2 provided by the present invention for formaldehyde;

[0040] Figure 3 The ultraviolet spectrum absorption diagram of the formaldehyde fluorescent probe compound of Example 2 provided in the detection example 2 of the present invention (C 探针化合物 =2×10 -6 mol / L);

[0041] Figure 4 The fluorescence increase spectrum of the formaldehyde fluorescent probe compound in Example 2 provided in the present invention in response to the concentration of formaldehyde (C 探针化合物 =2×10 -6 mol / L);

[0042] Figure 5 The linear fitting curve of the fluorescence response of the probe compound of Example 2 to formaldehyde and the detection limit calculation result diagram provided in Detection Example 2 of the present invention;

[0043] Figure 6 This is a bar graph of the fluorescence (825 nm) of the probe compound of Example 2 after acting on various molecules and ionic formaldehyde, provided in Detection Example 3 of the present invention. DETAILED DESCRIPTION

[0044] In order to make the purpose, technical scheme and advantages of the embodiments of the present invention clearer, the technical scheme in the embodiments of the present invention will be described clearly and completely below. If the specific conditions are not specified in the embodiments, they are carried out according to conventional conditions or conditions recommended by the manufacturer. If the manufacturer of the reagents or instruments used is not specified, they are all conventional products that can be purchased commercially.

[0045] The embodiment of the present invention provides a formaldehyde fluorescent probe compound, which is used to detect formaldehyde, and is selected from any one of the compounds represented by the following structural formulas:

[0046] Wherein, X is a halogen, and R1 is selected from any one of a substituted or unsubstituted alkyl group, a substituted or unsubstituted alcohol group, a substituted or unsubstituted carboxyl group, and a substituted or unsubstituted sulfonic acid group.

[0047] The construction of the formaldehyde fluorescent probe compound (hereinafter also referred to as the formaldehyde fluorescent probe molecule) provided in an embodiment of the present invention is mainly based on the conjugated modification of cyanine dyes. A long-range conjugated fluorescent molecule with near-infrared emission is prepared by the condensation reaction of dialdehyde and active methyl. The chlorine atom on the six-membered ring provides a reaction site for the introduction of reactive groups.

[0048] Specifically, the present invention selects cyanine dye as the luminescent main body, prepares asymmetric cyanine dye by chemical modification as a breakthrough point, introduces formaldehyde recognition group at the main recognition position of the molecule, and introduces hydrophilic groups at both ends of the molecule. Compared with the formaldehyde fluorescent probe molecule that has been reported, the formaldehyde fluorescent probe molecule of the present invention has good fluorescence specificity and high selectivity, shows good anti-interference performance to other metal and non-metal ions, and can effectively improve the detection sensitivity of fluorescence spectrophotometry. At the same time, the formaldehyde fluorescent probe molecule has red light emission fluorescence, which has obvious color change after combining with formaldehyde, and the fluorescence intensity is enhanced, which has the advantage of naked eye recognition, and can realize the rapid detection of formaldehyde in food and medicine. At the same time, the formaldehyde fluorescent probe compound has good chemical stability, good photostability, and simple synthesis steps and low cost.

[0049] Further, X is selected from bromine or iodine, preferably iodine.

[0050] In an optional embodiment, R1 is selected from any one of a C1-C5 unsubstituted alkyl group, a C2-C6 substituted hydroxyl group, a C3-C5 unsubstituted carboxyl group, and a C2-C5 substituted sulfonic acid group; preferably, R1 is selected from any one of a methyl group, a hydroxyethyl group, a propionic acid group, and a propanesulfonic acid group.

[0051] It should be noted that R1 can also be ethyl, n-propyl, isopropyl, n-butyl, hydroxymethyl, hydroxypropyl, formic acid group, acetic acid group, butyric acid group, methanesulfonic acid, ethanesulfonic acid, as well as alkyl groups such as yellow, substituted hydroxyl, carboxyl, and substituted sulfonic acid groups. The preferred embodiments of the present invention are merely examples of the embodiments of the present invention, and the formaldehyde fluorescent probe compound prepared by the above preferred embodiments has better effects.

[0052] Specifically, the formaldehyde fluorescent probe compound is selected from any one of the compounds represented by the following structural formulas:

[0053]

[0054] The present invention implements the construction of a cyanine dye with long-range intramolecular conjugation using two symmetrical indole or asymmetrical indole structures, designs and synthesizes a series of fluorescent formaldehyde probe compounds with intramolecular DA structures, wherein the active chlorine atoms on the formaldehyde probe molecules are active sites of hydrazine hydrate groups, and a condensation reaction occurs when the molecules come into contact with formaldehyde, and at the same time, the charge distribution within the molecules changes, resulting in changes in the absorption spectrum and emission spectrum of the molecules.

[0055] In the second aspect, the embodiment of the present invention provides a method for preparing the above-mentioned formaldehyde fluorescent probe compound, comprising synthesizing the formaldehyde fluorescent probe compound according to the following synthesis route 1 or synthesis route 2. The preparation method of the embodiment of the present invention uses indole as the luminescent main structure, realizes molecular functionalization modification by substitution reaction of conjugated chlorine atoms, and then synthesizes a near-infrared emitting fluorescent probe molecule with excellent photochemical stability and selective recognition of formaldehyde. The details are as follows:

[0056] Synthesis route 1:

[0057]

[0058] Wherein, X is a halogen, and R1 is selected from any one of a substituted or unsubstituted alkyl group, a substituted or unsubstituted alcohol group, a substituted or unsubstituted carboxyl group, and a substituted or unsubstituted sulfonic acid group.

[0059] Further, step 1: mixing an indole compound, an aldehyde compound, a first solvent and an organic base to react to form an intermediate (hereinafter also referred to as a chloroindole conjugated derivative); specifically, mixing an indole derivative, an aldehyde compound, such as cyclohexylchloroaldehyde, an organic base and a first solvent to react; wherein the molar ratio of the indole derivative to the aldehyde compound is 2.0-2.2:1; the reaction temperature is 80-85°C, and the reaction time is 8-12 hours; the first solvent is selected from at least one of ethanol, methanol and DMF. The organic base includes substances such as potassium acetate and sodium acetate.

[0060] Step 2: mixing the intermediate, hydrazine hydrate, a catalyst and a second solvent for reaction; specifically, mixing a chloroindole conjugated derivative, hydrazine hydrate, a catalyst and a second solvent for reaction; wherein the catalyst is an organic base such as potassium acetate, sodium acetate and the like, preferably potassium acetate; the second solvent is at least one of DMSO, DMF, THF, acetonitrile and ethanol; the molar ratio of the chloroindole conjugated derivative and hydrazine hydrate is 1:1, the reaction temperature is -10-0°C, and the reaction time is 0.5-1 hour.

[0061] Synthesis Path 2:

[0062]

[0063] Wherein, X is a halogen, and R1 is selected from any one of a substituted or unsubstituted alkyl group, a substituted or unsubstituted alcohol group, a substituted or unsubstituted carboxyl group, and a substituted or unsubstituted sulfonic acid group.

[0064] Further, step 1:

[0065] Two indole compounds, an aldehyde compound, a first solvent and an organic base are mixed and reacted to form a chloroindole conjugated derivative; specifically, an indole derivative, an aldehyde compound, such as cyclohexylchloroaldehyde, an organic base and a first solvent are mixed and reacted; wherein the molar ratio of the two indole derivatives to the aldehyde compound is 2:1; the reaction temperature is 80-85°C, and the reaction time is 8-12 hours; the first solvent is selected from at least one of ethanol, methanol and DMF. The organic base includes potassium acetate, sodium acetate and the like.

[0066] Step 2: mixing the intermediate, hydrazine hydrate, a catalyst and a second solvent for reaction; specifically, mixing a chloroindole conjugated derivative, hydrazine hydrate, a catalyst and a second solvent for reaction; wherein the catalyst is an organic base such as potassium acetate, sodium acetate and the like, preferably potassium acetate; the second solvent is at least one of DMSO, DMF, THF, acetonitrile and ethanol; the molar ratio of the chloroindole conjugated derivative and hydrazine hydrate is 1:1, the reaction temperature is -10-0°C, and the reaction time is 0.5-1 hour.

[0067] In a third aspect, the present invention provides a use of the formaldehyde fluorescent probe compound described in the aforementioned embodiment in detecting formaldehyde.

[0068] Preferably, the application comprises application in the detection of food.

[0069] In a fourth aspect, the present invention provides a formaldehyde spectrochemical sensor, which is prepared using the formaldehyde fluorescent probe compound described in the aforementioned embodiment.

[0070] In a fifth aspect, the present invention provides a method for detecting formaldehyde, which uses the formaldehyde fluorescent probe compound described in the aforementioned embodiment or the formaldehyde spectrochemical sensor described in the aforementioned embodiment for detection.

[0071] The features and performance of the present invention are further described in detail below in conjunction with the embodiments.

[0072] Example 1

[0073] The embodiment of the present invention provides a formaldehyde fluorescent probe compound, the structural formula of which is shown below:

[0074]

[0075] The present invention provides a method for preparing the above-mentioned formaldehyde fluorescent probe compound, comprising:

[0076] S1, synthetic intermediate YD-Cl;

[0077] The details are as follows:

[0078] Specifically, 2.5g (6.5mmol) of compound YD-A and 0.55g (3.2mmol) of compound YD-B were dissolved in 50ml of anhydrous ethanol in a 250mL two-necked bottle, 1.2g (12mmol) of potassium acetate was added, and the mixture was reacted in an oil bath at 80-85°C for 8-12h. The reaction progress was monitored by a thin layer chromatography plate. After the reaction was completed, the mixture was cooled to room temperature, and a large amount of green solid was washed out. The compound YD-Cl was recrystallized from ethanol to obtain 1.6g of compound YD-Cl with a yield of 85%. 1 H NMR (300MHz, CDCl3) δ8.36-8.33(d,J=9Hz,6H),7.43-7.37(m,6H),7.27-7.18(m,4H),6.26-6.23(d,J=9Hz,4H),4 .8(s,OH,2H),3.77(s,6H),3.58(m,4H),3.07(m,4H),2.78-2.75(t,J=6Hz,4H),1.99-1.96(t,2H),1.73(s,12H).

[0079] S2, synthesis of formaldehyde fluorescent probe compound YD-NH2;

[0080] The details are as follows:

[0081] Specifically, under nitrogen protection, 0.1 g (1.8 mmol) of hydrazine hydrate was dissolved in 50 ml of acetonitrile in a 250 mL two-necked flask. Under ice bath, 1.0 g (1.8 mmol) of compound YD-Cl was slowly added dropwise to the acetonitrile solution of hydrazine hydrate. Stirring was continued for 30 minutes. A large amount of yellow solid was generated. 0.8 g was obtained by suction filtration and drying. The yield was 80%. 1 H NMR (300MHz, CDCl3) δ8.36-8.33(d,J=9Hz,6H),7.42-7.35(m,6H),7.27-7.16(m,4H),6.25-6.22(d,J=9Hz,4H),4.8(s,OH,2H),4 .2(t,NH,1H),3.76(s,6H),3.56(m,4H),3.3(d,NH2,2H),3.07(m,4H),2.76-2.73(t,J=6Hz,4H),1.98-1.95(t,2H),1.72(s,12H).

[0082] Example 2

[0083] The embodiment of the present invention provides a formaldehyde fluorescent probe compound, the structural formula of which is shown below:

[0084]

[0085] The present invention provides a method for preparing the above-mentioned formaldehyde fluorescent probe compound, comprising:

[0086] S1, synthetic intermediate YD-FC1:

[0087]

[0088] The details are as follows:

[0089] Specifically, 1.2 g (3 mmol) of compound YD-C, 1 g (3 mmol) of compound YD-D, and 0.26 g (1.5 mmol) of YD-B were dissolved in 100 ml of anhydrous ethanol in a 250 mL two-necked bottle, and 0.6 g (6 mmol) of potassium acetate was added, and the mixture was reacted in an oil bath at 80-85° C. for 8-12 hours. The reaction progress was monitored by a thin layer chromatography plate, and after the reaction was completed, the mixture was cooled to room temperature, and a large amount of green solid was washed out, which was recrystallized from ethanol to obtain compound YD-FCl, 2.2 g, with a yield of 70%. 1 H NMR (300MHz, CDCl3) δ8.36-8.33(d,J=9Hz,4H),7.43-7.37(m,4H),7.27-7.18(m,4H),6.26-6.23(d,J=9Hz,4H),3.77(s,6H),1.73(s,12H).

[0090] S2, synthesis of formaldehyde fluorescent probe compound YD-FNH;

[0091] The details are as follows: Compound YD-FNH was obtained, 2.5 g, with a yield of 72%. 1 H NMR(300MHz, CDCl3)δ8.36-8.33(d,J=9Hz,4H),7.43-7.37(m,4H),7.27-7.18(m,4H), 6.26-6.23(d,J=9Hz,4H),4.2(t,NH,1H),3.77(s,6H),3.3(d,NH2,2H),1.73(s,12H).

[0092] Example 3

[0093] The embodiment of the present invention provides a formaldehyde fluorescent probe compound, the structural formula of which is shown below:

[0094]

[0095] The present invention provides a method for preparing the above-mentioned formaldehyde fluorescent probe compound, comprising:

[0096] S1, synthetic intermediate YD-SC1:

[0097]

[0098] The details are as follows:

[0099] Compound YD-SCl was obtained, 1.6 g, with a yield of 76%. 1 H NMR (300MHz, CDCl3) δ12.02 (s, COOH, 2H), 8.35-8.32 (d, J = 9Hz, 4H), 7.42-7.34 (m, 4H), 7.26 -7.16(m,4H),6.25-6.22(d,J=9Hz,4H),4.42-4.45(m,CH2CH2,4H),3.77(s,6H),2.28-2.30(m,CH2CH2,4H),1.73(s,12H).

[0100] S2. Synthesize formaldehyde fluorescent probe compound YD-SNH;

[0101] The details are as follows:

[0102] Compound YD-SNH was obtained, 1.5 g, yield: 78%. 1 H NMR (300MHz, CDCl3) δ12.00 (s, COOH, 2H), 8.36-8.33 (d, J = 9Hz, 4H), 7.43-7.37 (m, 4H), 7.27 -7.18(m,4H),6.26-6.23(d,J=9Hz,4H),4.42-4.45(m,CH2CH2,4H),4.20(t,NH ,1H),3.77(s,6H),3.34(d,NH2,2H),2.28-2.30(m,CH2CH2,4H),1.72(s,12H).

[0103] Test Example 1

[0104] The formaldehyde fluorescent probe compound of Example 2 (concentration of 2×10 -6 mol / L) was added dropwise with formaldehyde solution (molar ratio of probe: formaldehyde = 1:1), and the color change of the added formaldehyde solution was detected under ultraviolet light (365 nm).

[0105] Results Figure 1 ,in, Figure 1 The left picture shows the color of the fluorescent probe compound solution before adding formaldehyde, and the right picture shows the color of the fluorescent probe compound solution after adding formaldehyde. Figure 1It can be seen that the formaldehyde probe compound provided in the embodiment of the present invention can effectively react with formaldehyde and can effectively detect formaldehyde. The mechanism diagram of the action of the probe compound and formaldehyde in Example 2 is shown in FIG. Figure 2 .

[0106] Test Example 2

[0107] Detection Example 2: The fluorescence response of the formaldehyde fluorescent probe compound to the concentration of formaldehyde.

[0108] The method is as follows: add formaldehyde fluorescent probe compound solution (concentration 2×10 -6 mol / L) was added with formaldehyde (concentration of 5×10 -4 mol / L), and then the UV absorbance of the compound was measured by UV-visible spectrophotometer to obtain the UV spectrum absorption diagram ( Figure 3 ).

[0109] Add formaldehyde fluorescent probe compound solution (concentration 2×10 -6 mol / L) was added dropwise with formaldehyde (concentration of 0-5×10 -4 mol / L), and immediately monitor the fluorescence spectrum of the compound to obtain the fluorescence increase spectrum of the compound in response to formaldehyde concentration ( Figure 4 ).

[0110] Add formaldehyde fluorescent probe compound solution to a series of formaldehyde solutions from low to high concentrations. After addition, measure the fluorescence spectrum of the compound (excitation wavelength 785nm, emission wavelength 825nm). With the concentration of formaldehyde / fluorescent probe molecule as the horizontal coordinate and the fluorescence intensity as the vertical coordinate, obtain the linear fitting curve of the fluorescence response of the probe compound to formaldehyde. Figure 5 .

[0111] according to Figure 3 and Figure 4 It can be seen that the emission wave intensity of the probe molecule gradually increases as the formaldehyde concentration changes.

[0112] Test Example 3

[0113] Detection Example 2: Formaldehyde fluorescent probe compound performs fluorescence detection on different molecules and ions and formaldehyde

[0114] The method is as follows: add a formaldehyde fluorescent probe compound solution (concentration 2×10 -6 mol / L) were added to Br - ,Cl - ,SO4 2- ,CO3 2- ,F - ,PO4 3- ,H2O2,Fe 3+ ,Ag + ,CN -,Ni 2+ ,FA,Zn 2+ ,ClO - solution, in which the formaldehyde concentration is 5×10 -4 mol / L, hydrogen peroxide concentration is 10 -3 mol / L, the inorganic ion concentration is 5×10 -3 After reacting at room temperature for 10 min, the fluorescence emission intensity of the compound was measured at 825 nm and the results were analyzed.

[0115] Results Figure 6 , where 1-14, 1'-14' respectively represent Br - ,Cl - ,SO4 2- ,CO3 2- ,F - ,PO4 3- ,H2O2,Fe 3+ ,Ag + ,CN - ,Ni 2+ ,FA,Zn 2+ ,ClO - according to Figure 6 It can be seen that the probe molecules show good anti-interference properties to other metal and non-metal ions.

[0116] Test Example 4

[0117] Detection Example 2 The formaldehyde fluorescent probe compound is used to perform fluorescence detection of formaldehyde in the squid soaking solution.

[0118] Method: Take fresh squid samples and add them to -5 mol / L formaldehyde aqueous solution, soak for 30 minutes. Take 10mL of squid soaking liquid, add 1mL DMSO solvent, and shake for 1 minute. After centrifugation, take 5mL of supernatant, add formaldehyde fluorescent probe compound solution, and make up to 10mL with 10% DMSO solution. The concentration of formaldehyde fluorescent probe compound in this solution is 2×10 -6 mol / L, shake well and let stand for 5 minutes before fluorescence detection. Figure 5 ) can quantitatively measure the formaldehyde content.

[0119] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A formaldehyde fluorescent probe compound, characterized in that: It is used to detect formaldehyde, which is selected from the compounds shown in the following structural formula: , wherein X is halogen and R1 is selected from C1-C5 unsubstituted alkyl.

2. The formaldehyde fluorescent probe compound according to claim 1, characterized in that X is selected from bromine or iodine.

3. The formaldehyde fluorescent probe compound according to claim 1, characterized in that X is selected from iodine.

4. The formaldehyde fluorescent probe compound according to claim 1, characterized in that R1 is selected from methyl.

5. The formaldehyde fluorescent probe compound according to any one of claims 1 to 4, characterized in that: It is selected from the compounds represented by the following structural formula: 。 6. A method for preparing the formaldehyde fluorescent probe compound according to claim 1, characterized in that: The method comprises synthesizing the formaldehyde fluorescent probe compound according to the following synthesis route: Synthesis Path 2: ； Wherein, X is halogen, and R1 is selected from C1-C5 unsubstituted alkyl.

7. The preparation method according to claim 6, characterized in that: In synthesis route 2: Step 1: mixing two indole compounds, an aldehyde compound, a first solvent and an organic base to react to form an intermediate; Step 2: mixing the intermediate, hydrazine hydrate, a catalyst and a second solvent to react.

8. The preparation method according to claim 7, characterized in that: In synthesis route 2: Step 1: The molar ratio of the two indole compounds to the aldehyde compound is 2:1, the reaction temperature is 80-85° C., and the reaction time is 8-12 hours; Step 2: The molar ratio of the intermediate to the hydrazine hydrate is 1:1, the reaction temperature is -10-0°C, and the reaction time is 0.5-1.0 hour.

9. Use of the formaldehyde fluorescent probe compound according to claim 1 in detecting formaldehyde.

10. The use according to claim 9, characterized in that: Applications include testing in food and pharmaceuticals.

11. A formaldehyde spectral chemical sensor, characterized in that: The formaldehyde fluorescent probe is prepared using the formaldehyde fluorescent probe compound described in claim 1.

12. A method for detecting formaldehyde for non-diagnostic purposes, characterized in that: The formaldehyde fluorescent probe compound according to claim 1 or the formaldehyde spectrochemical sensor according to claim 11 is used for detection.

Images