CN114921243A

CN114921243A - Preparation method of fluorescence probe based on lanthanide ion self-assembly

Info

Publication number: CN114921243A
Application number: CN202210647777.1A
Authority: CN
Inventors: 贾琼; 穆晋; 黄臻臻; 李松芮; 曹琪
Original assignee: Jilin University
Current assignee: Jilin University
Priority date: 2022-06-08
Filing date: 2022-06-08
Publication date: 2022-08-19

Abstract

The invention discloses a preparation method of a fluorescence probe based on lanthanide ion self-assembly, belonging to the technical field of fluorescence sensing, and the technical key points are as follows: preparing aqueous solution containing metal ions with a certain concentration, adjusting the pH value of the aqueous solution to a proper pH value by using the pH value, and adding a ligand (reducing agent) to react to prepare Metal Nanoclusters (MNCs); obtaining BMNCs based on metal doping by adding another metal ion solution into the solution; lanthanide ions are used as an initiator of AIE self-assembly, and are fully mixed with BMNCs, so that carboxyl on ligands of the BMNCs and the lanthanide ions are subjected to coordination reaction, and the AIE self-assembly material (namely, a fluorescent probe) of lanthanide ion regulated bimetallic nanoclusters (BMNCs) is prepared, the probe can realize detection of anticancer drug Methotrexate (MTX) through a fluorescence 'turn-off' phenomenon, the fluorescence phenomenon is obviously changed, and the response time is short. Compared with other fluorescent probes, the probe has the advantages of short preparation time, quick response, high sensitivity and the like.

Description

Preparation method of fluorescence probe based on lanthanide ion self-assembly

Technical Field

The invention relates to the technical field of fluorescence sensing, in particular to a preparation method of a fluorescence probe based on lanthanide ion self-assembly.

Background

Methotrexate (MTX), a folate antagonist, is used clinically in the treatment of various inflammatory diseases and cancers. MTX has been reported to affect hundreds of cancer cell lines, such as acute lymphocytic leukemia, breast cancer, lymphoma, head and neck cancer, and fibroblast tumors. MTX can inhibit the function of dihydrofolate reductase, and further inhibit the synthesis of DNA and RNA. Maintaining high concentrations of MTX can result in effective treatment, but can result in severe toxic side effects such as pancreatitis, ulcerative stomatitis, and liver injury. Furthermore, pharmacokinetics varies from patient to patient, especially in patients with renal or hepatic insufficiency. Thus, sensitive monitoring of the concentration of MTX in blood not only optimizes drug dosage, but also achieves maximum therapeutic efficacy and minimal adverse effects.

Currently, a variety of analytical methods have been developed for the detection of MTX, including immunoassays, high performance liquid chromatography, uv-vis spectrophotometry, electrochemical analysis, mass spectrometry, and capillary electrophoresis. Although these methods have the advantage of being sensitive and accurate, they have the inherent disadvantages of being cumbersome in handling, time consuming and complex in analysis, expensive in instrumentation, etc. Therefore, it is important to develop a simple, sensitive and inexpensive MTX detection method.

In this regard, fluorescence has received much attention in recent years because of its advantages of being rapid, simple, sensitive, specific, low cost, and environmentally friendly. Among numerous fluorescent probes, Metal Nanoclusters (MNCs) are widely used in the sensing field as a promising luminescent material with the advantages of ultra-small average diameter, large stokes shift, tunable emission, good biocompatibility and the like. In recent years, bimetallic nanoclusters (BMNCs) that integrate two metals into one cluster based on intermetallic interactions have received attention. BMNCs have higher fluorescence intensity and greater stability than MNCs. In the research, lanthanide ions are used for inducing BMNCs to generate aggregates, a stable fluorescent material is synthesized, the excitation wavelength of the material is overlapped with the absorption wavelength of MTX, the existence of MTX can quench the fluorescence of the probe through an internal filtering effect, and the detection of MTX is realized through the phenomenon of fluorescence 'turn-off'.

Disclosure of Invention

In view of the defects in the prior art, an object of the embodiments of the present invention is to provide a method for preparing a fluorescence probe based on lanthanide ion self-assembly, so as to solve the above-mentioned problems in the background art.

In order to achieve the purpose, the invention provides the following technical scheme:

a preparation method of a fluorescence probe based on lanthanide ion self-assembly comprises the following steps:

1) synthesis of MNCs material:

11) adding copper nitrate into 5 mL of aqueous solution at room temperature, and stirring to dissolve the copper nitrate;

12) adding a copper nitrate solution into 5 mL of glutathione solution;

13) 1 mL of sodium hydroxide solution is added dropwise for adjusting the pH value; and

14) adjusting the pH value to 5, and reacting for a period of time to obtain a CuNCs solution;

2) synthesis of BMNCs materials:

21) adding copper nitrate into 5 mL of aqueous solution at room temperature, and stirring to dissolve the copper nitrate;

22) adding a copper nitrate solution into 5 mL of glutathione solution;

23) 1 mL of sodium hydroxide solution is added dropwise for adjusting the pH value; and

24) after the pH value is adjusted to 5, introducing the silver nitrate solution into the system and stirring to obtain an AgCuNCs solution;

3) synthesis of AIE self-assembled materials of lanthanide ion-mediated bimetallic nanoclusters (BMNCs):

31) adding 200 mu L of AgCuNCs prepared in the step 2) into terbium nitrate solutions with different volumes;

32) adding distilled water into a terbium nitrate solution to dilute the solution to 2 mL; and

33) stirring the mixture at room temperature for a period of time to obtain lanthanide ion induced BMNCs aggregates.

As a further scheme of the invention, the molar ratio of the copper nitrate to the glutathione in the step 1) is (0.5-1.5) to (3-5).

As a further variant of the invention, the reaction time of step 1) is from 6 to 8 hours.

As a further embodiment of the present invention, the reaction temperature in step 1) is room temperature.

As a further scheme of the invention, the molar ratio of the copper nitrate to the silver nitrate in the step 2) is (5) to (3-5).

As a further scheme of the invention, the reaction time of the step 2) is 6-8 h.

As a further embodiment of the present invention, the reaction temperature in step 2) is room temperature.

As a further scheme of the invention, the volume of the terbium nitrate solution in the step 3) is 50-300 mu L.

As a further scheme of the invention, the reaction time of the step 3) is 5-15 min.

As a further scheme of the invention, the AIE self-assembly material of the terbium ion regulated bimetallic nanoclusters (BMNCs) is spherical in appearance and 130 nm in average diameter.

In summary, compared with the prior art, the embodiment of the invention has the following beneficial effects:

adding another metal ion solution into the solution, and obtaining bimetallic nano-clusters (BMNCs) based on metal doping; lanthanide ions are used as an initiator of AIE self-assembly, and are fully mixed with BMNCs, so that carboxyl on BMNCs ligands and lanthanide ions are subjected to coordination reaction, and the AIE self-assembly material (namely a fluorescent probe) of lanthanide ion regulation bimetallic nanoclusters (BMNCs) is prepared. The fluorescent probe synthesized by the invention has the advantages of BMNCs and AIE, the preparation method is simple and convenient, the prepared probe has good stability, long fluorescence life and high fluorescence intensity, and the introduction of lanthanide ions triggers the self-assembly of the BMNCs, thereby being beneficial to improving the identification capability of the probe. The probe can realize the detection of the anticancer drug Methotrexate (MTX) through the phenomenon of fluorescence 'turn-off', the fluorescence phenomenon change is obvious, and the response time is short. Compared with other fluorescent probes, the probe has the advantages of short preparation time, quick response, high sensitivity and the like.

To more clearly illustrate the structural features and effects of the present invention, the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

Drawings

FIG. 1 is a fluorescence emission spectrum of AIE self-assembled material of lanthanide ion-mediated bimetallic nanoclusters (BMNCs) prepared in example 1.

FIG. 2 is a fluorescence emission spectrum of AIE self-assembled material of lanthanide ion-mediated bimetallic nanoclusters (BMNCs) prepared in example 2.

FIG. 3 is a fluorescence emission spectrum of AIE self-assembled material of lanthanide ion-mediated bimetallic nanoclusters (BMNCs) prepared in example 3.

FIG. 4 is a fluorescence emission spectrum of AIE self-assembled material of lanthanide ion-regulated bimetallic nanoclusters (BMNCs) prepared in example 4.

FIG. 5 is a fluorescence emission spectrum of AIE self-assembled material of lanthanide ion-mediated bimetallic nanoclusters (BMNCs) prepared in example 5.

FIG. 6 is a TEM image of AIE self-assembled material of lanthanide ion-mediated bimetallic nanoclusters (BMNCs) prepared in example 4.

FIG. 7 is an EDS diagram of AIE self-assembled materials of lanthanide ion-mediated bimetallic nanoclusters (BMNCs) prepared in example 4.

FIG. 8 is a fluorescence spectrum of MTX quenching AIE self-assembled material of lanthanide ion-mediated bimetallic nanoclusters (BMNCs) prepared in example 4 as described herein.

FIG. 9 is the fluorescence spectrum of AIE self-assembly material of lanthanide ion-regulated bimetallic nanoclusters (BMNCs) prepared in example 4 for detecting MTX with different concentrations.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

Specific implementations of the present invention are described in detail below with reference to specific embodiments.

In one embodiment, a method for preparing a fluorescence probe based on lanthanide ion self-assembly, see fig. 1-9, comprises the following steps:

1) synthesis of MNCs material:

12) adding a copper nitrate solution into 5 mL of glutathione solution;

2) synthesis of BMNCs materials:

22) adding a copper nitrate solution into 5 mL of glutathione solution;

32) adding distilled water into the terbium nitrate solution to dilute the solution to 2 mL; and

Further, referring to fig. 1 to 9, the molar ratio of copper nitrate to glutathione in the step 1) is (0.5-1.5) to (3-5).

Further, referring to fig. 1 to 9, the reaction time of the step 1) is 6 to 8 hours.

Further, referring to fig. 1 to 9, the reaction temperature of step 1) is room temperature.

Further, referring to fig. 1 to 9, the molar ratio of the copper nitrate to the silver nitrate in the step 2) is (5) to (3-5).

Further, referring to fig. 1 to 9, the reaction time of the step 2) is 6 to 8 hours.

Further, referring to fig. 1 to 9, the reaction temperature of the step 2) is room temperature.

Further, referring to fig. 1 to 9, the volume of the terbium nitrate solution of the step 3) is 50 to 300 μ L.

Further, referring to fig. 1 to 9, the reaction time of the step 3) is 5 to 15 min.

Further, referring to fig. 1 to 9, the AIE self-assembly material of terbium ion-regulated bimetallic nanoclusters (BMNCs) has a spherical appearance and an average diameter of 130 nm.

Example 1

1) Synthesis of MNCs material:

briefly, copper nitrate (12.1 mg) was added to 5 mL of an aqueous solution at room temperature, dissolved with stirring, and then added to 5 mL of glutathione (60 mM) solution (0.5: 3). And (3) dropwise adding a sodium hydroxide solution (1M) to adjust the pH value, and reacting at room temperature for 6 h after the pH value is adjusted to 5 to obtain a CuNCs solution.

2) Synthesis of BMNCs materials:

briefly, copper nitrate (24.2 mg) was added to 5 mL of an aqueous solution at room temperature, dissolved with stirring, and then added to 5 mL of glutathione (80 mM) solution. And dropwise adding a sodium hydroxide solution (1M) to adjust the pH value, introducing 1 mL of silver nitrate solution (10.2 mg) into the system after the pH value is adjusted to 5, and stirring at room temperature for 6 hours to obtain the AgCuNCs solution.

3) Synthesis of AIE self-assembled materials of lanthanide ion mediated bimetallic nanoclusters (BMNCs):

adding 200 mu.L of AgCuNCs prepared in the step 2) into 50 mu.L of terbium nitrate solution (10 mM), adding distilled water to dilute to 2 mL, and stirring and reacting at room temperature for 5 min to obtain the terbium ion-regulated AgCuNCs aggregate.

(4) Fluorescence sensing of AIE self-assembled materials of lanthanide ion mediated bimetallic nanoclusters (BMNCs): mu.L of HAc-NaAc buffer solution (pH =5.0, 0.2M) was removed, 200. mu.L of probe solution was added to the tube, and then MTX solution of various concentrations was added, diluted to 2.5 mL with deionized water, and subjected to fluorescence detection.

Example 2

1) Synthesis of MNCs material:

briefly, copper nitrate (24.2 mg) was added to 5 mL of an aqueous solution at room temperature, dissolved with stirring, and then added to 5 mL of a glutathione (80 mM) solution (1: 4). And (3) dropwise adding a sodium hydroxide solution (1M) to adjust the pH value, and reacting at room temperature for 6 h after the pH value is adjusted to 5 to obtain a CuNCs solution.

2) Synthesis of BMNCs materials:

briefly, copper nitrate (24.2 mg) was added to 5 mL of an aqueous solution at room temperature, dissolved with stirring, and then added to 5 mL of glutathione (80 mM) solution. And dropwise adding a sodium hydroxide solution (1M) to adjust the pH value, introducing 1 mL of silver nitrate solution (13.6 mg) into the system after the pH value is adjusted to be 5, and stirring at room temperature for 6 hours to obtain the AgCuNCs solution.

adding 200 mu L of AgCuNCs prepared in the step 2) into 150 mu L of terbium nitrate solution (10 mM), adding distilled water to dilute the solution to 2 mL, and stirring the solution at room temperature for 5 min to obtain terbium ion-regulated AgCuNCs aggregates.

(4) Fluorescence sensing of AIE self-assembled materials of lanthanide ion mediated bimetallic nanoclusters (BMNCs): mu.L of HAc-NaAc buffer solution (pH =5.0, 0.2M) was removed, 200. mu.L of the probe solution was added to the tube, and then, MTX solutions of various concentrations were added, diluted to 2.5 mL with deionized water, and subjected to fluorescence detection.

Example 3

1) Synthesis of MNCs material:

briefly, copper nitrate (36.3 mg) was added to 5 mL of an aqueous solution at room temperature, dissolved with stirring, and then added to 5 mL of a glutathione (100 mM) solution (1.5: 5). And (3) dropwise adding a sodium hydroxide solution (1M) to adjust the pH value, and reacting at room temperature for 6 h after the pH value is adjusted to 5 to obtain a CuNCs solution.

2) Synthesis of BMNCs materials:

briefly, copper nitrate (24.2 mg) was added to 5 mL of an aqueous solution at room temperature, dissolved with stirring, and then added to 5 mL of glutathione (80 mM) solution. And dropwise adding a sodium hydroxide solution (1M) to adjust the pH value, introducing 1 mL of silver nitrate solution (17.0 mg) into the system after the pH value is adjusted to 5, and stirring at room temperature for 6 hours to obtain the AgCuNCs solution.

adding 200 mu L of AgCuNCs prepared in the step 2) into 150 mu L of terbium nitrate solution (10 mM), adding distilled water to dilute the solution to 2 mL, and stirring and reacting the solution for 15 min at room temperature to obtain the terbium ion-regulated AgCuNCs aggregate.

Example 4

1) Synthesis of MNCs material:

briefly, copper nitrate (24.2 mg) was added to 5 mL of an aqueous solution at room temperature, dissolved with stirring, and then added to 5 mL of a glutathione (80 mM) solution (1: 4). And (3) dropwise adding a sodium hydroxide solution (1M) to adjust the pH value, and reacting for 7 hours at room temperature after the pH value is adjusted to be 5 to obtain the CuNCs solution.

2) Synthesis of BMNCs materials:

briefly, copper nitrate (24.2 mg) was added to 5 mL of an aqueous solution at room temperature, dissolved with stirring, and then added to 5 mL of glutathione (80 mM) solution. And dropwise adding a sodium hydroxide solution (1M) to adjust the pH value, introducing 1 mL of silver nitrate solution (13.6 mg) into the system after the pH value is adjusted to be 5, and stirring at room temperature for 7 hours to obtain the AgCuNCs solution.

adding 200 mu L of AgCuNCs prepared in the step 2) into 150 mu L of terbium nitrate solution (10 mM), adding distilled water to dilute the solution to 2 mL, and stirring and reacting the solution for 10 min at room temperature to obtain the terbium ion-regulated AgCuNCs aggregate.

Example 5

1) Synthesis of MNCs material:

briefly, copper nitrate (24.2 mg) was added to 5 mL of an aqueous solution at room temperature, and dissolved by stirring, then added to 5 mL of a glutathione (80 mM) solution (1: 4), and a sodium hydroxide solution (1M) was added dropwise to adjust the pH, and after adjusting to pH 5, the reaction was carried out at room temperature for 8 hours to obtain a CuNCs solution.

2) Synthesis of BMNCs materials:

briefly, copper nitrate (24.2 mg) was added to 5 mL of an aqueous solution at room temperature, dissolved with stirring, and then added to 5 mL of glutathione (80 mM) solution. And dropwise adding a sodium hydroxide solution (1M) to adjust the pH value, introducing 1 mL of silver nitrate solution (13.6 mg) into the system after the pH value is adjusted to be 5, and stirring at room temperature for 8 hours to obtain the AgCuNCs solution.

adding 200 mu L of AgCuNCs prepared in the step 2) into 300 mu L of terbium nitrate solution (10 mM), then adding distilled water to dilute the solution to 2 mL, and stirring and reacting the solution for 15 min at room temperature to obtain the terbium ion-regulated AgCuNCs aggregate.

4) Fluorescence sensing of AIE self-assembled materials of lanthanide ion mediated bimetallic nanoclusters (BMNCs): mu.L of HAc-NaAc buffer solution (pH =5.0, 0.2M) was removed, 200. mu.L of probe solution was added to the tube, and then MTX solution of various concentrations was added, diluted to 2.5 mL with deionized water, and subjected to fluorescence detection.

Specifically, the fluorescent probe can be used for fluorescence sensing of the anticancer drug MTX: MTX was added to the fluorescent probe of example 4 at an excitation wavelength of 352 nm, an emission wavelength of 564 nm, an excitation light source slit of 10 nm, and an emission light source slit of 10 nm, and fluorescence detection was carried out using a cuvette of 1 cm. times.1 cm. As can be seen from FIG. 8, the addition of MTX solution significantly quenches the fluorescence of the probe. As can be seen from fig. 9, the fluorescence intensity gradually decreased with increasing concentration of MTX, and sensitive detection of MTX was achieved.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.

Claims

1. A preparation method of a fluorescence probe based on lanthanide ion self-assembly is characterized by comprising the following steps:

1) synthesis of MNCs material:

12) adding a copper nitrate solution into 5 mL of glutathione solution;

14) adjusting the pH value to 5, and reacting for a period of time to obtain a copper nanocluster (CuNCs) solution;

2) synthesis of BMNCs materials:

22) adding a copper nitrate solution into 5 mL of glutathione solution;

24) after the pH value is adjusted to 5, introducing the silver nitrate solution into the system and stirring to obtain a silver-copper nanocluster (AgCuNCs) solution;

33) and stirring the mixture at room temperature for a period of time to obtain lanthanide ion-induced BMNCs aggregates.

2. The method for preparing the AIE self-assembled fluorescent probe based on lanthanide ion modulated bimetallic nanoclusters (BMNCs) as recited in claim 1, wherein the molar ratio of copper nitrate to glutathione in step 1) is (0.5-1.5): (3-5).

3. The method for preparing the AIE self-assembled fluorescent probe based on lanthanide ion mediated bimetallic nanoclusters (BMNCs) as claimed in claim 1, wherein the reaction time of step 1) is 6-8 h.

4. The method for preparing AIE self-assembled fluorescent probes based on lanthanide ion mediated bimetallic nanoclusters (BMNCs) of claim 1, wherein the reaction temperature of step 1) is room temperature.

5. The method for preparing an AIE self-assembled fluorescent probe based on lanthanide ion modulated bimetallic nanoclusters (BMNCs) as recited in claim 1, wherein the molar ratio of copper nitrate to silver nitrate in step 2) is (5) to (3-5).

6. The method for preparing the AIE self-assembled fluorescent probe based on lanthanide ion mediated bimetallic nanoclusters (BMNCs) as claimed in claim 1, wherein the reaction time of step 2) is 6-8 h.

7. The method for preparing the AIE self-assembled fluorescent probe based on lanthanide ion mediated bimetallic nanoclusters (BMNCs) as claimed in claim 1, wherein the reaction temperature of step 2) is room temperature.

8. The method for preparing an AIE self-assembled fluorescent probe based on lanthanide ion mediated bimetallic nanoclusters (BMNCs) according to claim 1, wherein the volume of the terbium nitrate solution of step 3) is 50-300 μ L.

9. The method for preparing the AIE self-assembled fluorescent probe based on lanthanide ion mediated bimetallic nanoclusters (BMNCs) as claimed in claim 1, wherein the reaction time of step 3) is 5-15 min.

10. The method for preparing an AIE self-assembled fluorescent probe based on lanthanide ion regulated bimetallic nanoclusters (BMNCs) as in claim 1, wherein the AIE self-assembled material of terbium ion regulated bimetallic nanoclusters (BMNCs) is spherical in appearance and has an average diameter of 130 nm.