阅读说明：本技术 一种共聚物及其制备方法与应用 (Copolymer and preparation method and application thereof ) 是由 李新宇 刘翔 文韬 徐蒙蒙 贾毅凡 于倩倩 王林格 于 2021-08-23 设计创作，主要内容包括：本发明公开了一种共聚物及其制备方法与应用,本发明的共聚物的光谱响应较宽且水溶性好；同时该共聚物由于亚甲烯丙交酯与2-乙烯基吡啶间特殊的分子内相互作用,无论在稀溶液还是固态状态下都具有很高的发光效率,通过调节亚甲烯丙交酯和(2-乙烯基吡啶)的比例,进一步调节了共聚物的发光强度和发光波长；同时,共聚物还具有激发依赖性,在不同的激发波长会产生不同的发射波长。由于亚甲烯丙交酯-(2-乙烯基吡啶)共聚物采用自由基聚合,聚合方法简单,成本低廉,并且还是一种水溶性发光材料,在生物/细胞成像、细胞标记等领域具有广泛的应用前景。(The invention discloses a copolymer and a preparation method and application thereof, and the copolymer has wider spectral response and good water solubility; meanwhile, the copolymer has high luminous efficiency in a dilute solution state or a solid state due to the special intramolecular interaction between the methylene allyl lactide and the 2-vinylpyridine, and the luminous intensity and the luminous wavelength of the copolymer are further adjusted by adjusting the proportion of the methylene allyl lactide to the (2-vinylpyridine); at the same time, the copolymers also have an excitation dependence, which produces different emission wavelengths at different excitation wavelengths. Because the methylene allyl lactide- (2-vinylpyridine) copolymer adopts free radical polymerization, the polymerization method is simple, the cost is low, and the copolymer is a water-soluble luminescent material, and has wide application prospect in the fields of biological/cell imaging, cell marking and the like.)

1. A copolymer characterized by: the structural formula is shown as the following formula:

wherein x is 10-110; y is 9 to 100.

2. A copolymer according to claim 1, wherein: the mass content of the methylene allyl lactide unit in the copolymer is 10-90%; preferably, the mass content of the methylene lactide unit in the copolymer is 30-80%.

3. A copolymer according to claim 1, wherein: the excitation wavelength of the copolymer is 330 nm-390 nm; preferably, the copolymer has an emission wavelength of 400nm to 478 nm.

4. A process for preparing a copolymer according to any one of claims 1 to 3, characterized in that: the method comprises the following steps:

adding an organic solvent into a mixture of methylene allyl lactide, 2-vinylpyridine and an initiator under the atmosphere of inert gas I, reacting for 11.5-12.5 h at the temperature of 60-80 ℃, carrying out solid-liquid separation, and collecting a solid phase to obtain the copolymer.

5. The method of claim 4, wherein: the mol ratio of the methylene allylic lactide to the 2-vinyl pyridine to the initiator is 1-5: 1-5: 0.01 to 0.001; preferably, the molar ratio of the methallyl lactide, the 2-vinylpyridine and the initiator is 1: 1-5: 0.01 to 0.001; preferably, the molar ratio of the methallyl lactide to the 2-vinylpyridine to the initiator is 1-5: 1: 0.01 to 0.001; preferably, the volume mass ratio of the organic solvent to the methylene allyllactide is 10 mL: 0.1g to 1 g.

6. The method of claim 4, wherein: the inert gas I comprises at least one of helium, neon, argon, krypton and nitrogen; preferably, the organic solvent includes an ether solvent and an amide solvent; preferably, the ether solvent includes at least one of 1, 4-dioxane and tetrahydrofuran; preferably, the initiator includes azo-type initiators and peroxy-type initiators; preferably, the azo initiator comprises azodiethylbutyronitrile; preferably, the peroxy-type initiator comprises benzoyl peroxide.

7. The method according to claim 4 or 5, characterized in that: the preparation method of the methylene allyllactide comprises the following steps:

s1, preparing bromolactide:

adding L-lactide and N-bromosuccinimide into a hydrocarbon solvent for reaction for 22-26 h, carrying out solid-liquid separation, and collecting a solid phase to obtain bromolactide;

s2, preparation of methylene allyl lactide:

and under the atmosphere of inert gas II, adding the bromolactide into a halogenated solvent, dropwise adding triethylamine for reaction, extracting and collecting an organic phase, and concentrating to obtain the methylene allyl lactide.

8. The method of claim 7, wherein: in the step S1, the mass ratio of the L-lactide to the N-bromosuccinimide is 1: 1.25 to 1.35; preferably, the hydrocarbon solvent in step S1 includes aromatic hydrocarbon; preferably, the aromatic hydrocarbon comprises at least one of toluene and benzene; preferably, the inert gas ii in step S2 includes at least one of helium, neon, argon, krypton, and nitrogen; preferably, the halogenated solvent in step S2 comprises a halogenated alkane; preferably, the halogenated alkane comprises dichloromethane; preferably, the temperature of the reaction in step S2 is-10 ℃ to 10 ℃; preferably, the reaction time in step S2 is 2h to 4 h.

9. Use of a copolymer as claimed in any of claims 1 to 3 for the preparation of a luminescent material.

10. Use of a copolymer according to any one of claims 1 to 3 for cellular imaging.

Technical Field

The invention relates to the field of photoelectric materials, and particularly provides a copolymer and a preparation method and application thereof.

Background

The non-conjugated organic light-emitting polymer is a material with great potential in the fields of cell imaging and marking. Compared with the traditional luminescent polymer with a main chain conjugated structure, the non-conjugated organic luminescent polymer material has the advantages of low toxicity, biodegradability, good water solubility and the like. However, the non-conjugated organic light-emitting polymer has a very obvious disadvantage, and because the non-conjugated light-emitting polymer does not have a traditional luminophore, the light emission is derived from the aggregation of electron-rich groups such as carbonyl, hydroxyl, amino, carboxyl, sulfhydryl, methoxy and the like, i.e., the non-conjugated light-emitting polymer can show a light-emitting behavior under a high concentration or solid state condition, and the light-emitting characteristic is technically called cluster aggregation induced emission (CTE). Due to the characteristic of cluster induced luminescence of the non-conjugated polymer, the polymer material is difficult to express luminescence in a dilute solution, so that the application of the luminescent polymer in the fields of biological/cell imaging, cell marking and the like is limited.

Therefore, it is required to develop a copolymer having high luminous efficiency at a low concentration.

Disclosure of Invention

To solve the problems of the prior art, the present invention provides a copolymer having high luminous efficiency at a low concentration.

The invention also provides a preparation method of the copolymer.

The invention also provides application of the copolymer in preparing luminescent materials.

The invention also provides the application of the copolymer in cell imaging.

In a first aspect, the present invention provides a copolymer having the formula:

wherein x is 10-110; y is 9 to 100.

The copolymer according to at least one embodiment of the present invention has the following advantageous effects:

the copolymer has high luminous efficiency (1.1-21.8%) in a dilute solution (0.1-1 mg/mL) or a solid state due to a special intramolecular interaction between the methylene allyl lactide and the 2-vinylpyridine (namely, the transition from lone pair electron on pyridine ring N to N → pi of methylene allyl lactide carbonyl), and the luminous intensity and the luminous wavelength of the copolymer are further regulated by regulating the proportion of the methylene allyl lactide unit and the (2-vinylpyridine) unit; at the same time, the copolymers also have an excitation dependence, which produces different emission wavelengths at different excitation wavelengths.

According to some embodiments of the invention, the content by mass of the methylene lactide units in the copolymer is between 10% and 90%.

According to some embodiments of the invention, the content by mass of the methylene lactide units in the copolymer is between 30% and 80%.

According to some embodiments of the invention, the methyleneallylic lactide units have the formula:

wherein the dashed position represents the bond to the other unit.

According to some embodiments of the invention, the copolymer has an excitation wavelength of 330nm to 390 nm.

According to some embodiments of the invention, the copolymer has an emission wavelength of 400nm to 478 nm.

The second aspect of the present invention provides a method for producing the above copolymer, comprising the steps of:

adding an organic solvent into a mixture of methylene allyl lactide, 2-vinylpyridine and an initiator under the atmosphere of inert gas I, reacting for 11.5-12.5 h at the temperature of 60-80 ℃, carrying out solid-liquid separation, and collecting a solid phase to obtain the copolymer.

According to the preparation method in at least one embodiment of the invention, the following beneficial effects are achieved:

the preparation method of the invention adopts the polymerization principle of free radical polymerization, so the polymerization method is simple and the cost is low.

According to some embodiments of the invention, the molar ratio of the methallyl lactide, the 2-vinylpyridine and the azodiacetonitrile is from 1 to 5: 1-5: 0.01 to 0.001.

According to some embodiments of the invention, the molar ratio of the methyleneallylic lactide, the 2-vinylpyridine and the initiator is 1: 1-5: 0.01 to 0.001.

According to some embodiments of the invention, the molar ratio of the methallylide, the 2-vinylpyridine and the initiator is from 1 to 5: 1: 0.01 to 0.001.

According to some embodiments of the invention, the volume to mass ratio of the organic solvent to the methylene allyllactide is 10 mL: 0.1g to 1 g.

According to some embodiments of the invention, the inert gas i comprises at least one of helium, neon, argon, krypton, and nitrogen.

According to some embodiments of the invention, the organic solvent includes an ether solvent and an amide solvent.

According to some embodiments of the invention, the ethereal solvent comprises at least one of 1, 4-dioxane and tetrahydrofuran.

According to some embodiments of the invention, the initiator comprises an azo-type initiator and a peroxy-type initiator.

According to some embodiments of the invention, the azo-based initiator comprises azodiethylbutyronitrile.

According to some embodiments of the invention, the peroxy-type initiator comprises benzoyl peroxide.

According to some embodiments of the invention, the solid phase is added to methyl halide I, passed through a silica gel column, concentrated to obtain a solid powder, and dried at 70 ℃ to 90 ℃ for 2h to 3 h.

According to some embodiments of the invention, the halogenated methane i comprises at least one of methyl chloride, methylene chloride, chloroform, and carbon tetrachloride.

According to some embodiments of the invention, the method for preparing methylene allyllactide comprises the steps of:

s1, preparing bromolactide:

adding L-lactide and N-bromosuccinimide into a hydrocarbon solvent for reaction for 22-26 h, carrying out solid-liquid separation, and collecting a solid phase to obtain bromolactide;

s2, preparation of methylene allyl lactide:

and under the atmosphere of inert gas II, adding the bromolactide into a halogenated solvent, dropwise adding triethylamine for reaction, extracting and collecting an organic phase, and concentrating to obtain the methylene allyl lactide.

According to some embodiments of the invention, the mass ratio of the L-lactide to the N-bromosuccinimide in step S1 is 1: 1.25 to 1.35.

According to some embodiments of the invention, the hydrocarbon solvent in step S1 comprises an aromatic hydrocarbon.

According to some embodiments of the invention, the aromatic hydrocarbon comprises at least one of toluene and benzene.

According to some embodiments of the present invention, the inert gas ii in step S2 includes at least one of helium, neon, argon, krypton, and nitrogen.

According to some embodiments of the invention, the halogenated solvent in step S2 comprises a halogenated alkane.

According to some embodiments of the invention, the halogenated alkane comprises dichloromethane.

According to some embodiments of the invention, the temperature of the reaction in step S2 is between-10 ℃ and 10 ℃.

According to some embodiments of the invention, the reaction time in step S2 is 2h to 4 h.

According to some embodiments of the invention, the solid phase in step S1 is extracted once with methyl halide ii and sodium thiosulfate solution; collecting organic phase, extracting twice with saturated sodium chloride solution, liquid-liquid separating, collecting organic phase, concentrating, and recrystallizing with ester solvent.

According to some embodiments of the invention, the halogenated methane ii comprises at least one of methyl chloride, methylene chloride, chloroform, and carbon tetrachloride.

According to some embodiments of the invention, the sodium thiosulfate solution has a molar concentration of 0.5 to 1.5 mol/L.

According to some embodiments of the invention, the ester solvent comprises at least one of ethyl acetate, methyl formate and ethyl formate.

According to some embodiments of the invention, the reaction described in step S2, followed by one extraction with hydrochloric acid and two extractions with saturated sodium chloride solution, is concentrated.

According to some embodiments of the invention, the hydrochloric acid has a molar concentration of 0.5mol/L to 1.5 mol/L.

According to some embodiments of the invention, the solid in step S2 is purified by column chromatography.

According to some embodiments of the invention, the column chromatography purification, the eluents used in the purification are dichloromethane and petroleum ether; preferably, the volume ratio of the dichloromethane to the petroleum ether is 1: 0.5 to 2.

The third aspect of the present invention provides the use of the above copolymer in the preparation of a luminescent material.

In a fourth aspect the present invention provides the use of a copolymer as described above in cellular imaging.

According to at least one embodiment of the present invention, the following technical effects are provided:

the copolymer has wider spectral response (the range of excitation wavelength is 330 nm-390 nm, the range of the responsive fluorescence emission peak is 408 nm-475 nm) and good water solubility; meanwhile, due to the special intramolecular interaction between the methylene allyl lactide and the 2-vinylpyridine, the copolymer has high luminous efficiency in a dilute solution state or a solid state, and has wide reasons in the fields of biological/cell imaging, cell marking and the like.

Drawings

FIG. 1 shows the UV-Vis spectrum and photoluminescence spectrum of a PMVP-1 copolymer prepared in example 1 of the present invention;

FIG. 2 shows the UV-Vis spectrum and photoluminescence spectrum of the PMVP-2 copolymer prepared in example 2 of the present invention;

FIG. 3 shows the UV-Vis spectrum and photoluminescence spectrum of the PMVP-3 copolymer prepared in example 3 of the present invention;

FIG. 4 shows the UV-Vis spectrum and photoluminescence spectrum of the PMVP-4 copolymer prepared in example 4 of the present invention;

FIG. 5 shows the UV-Vis spectrum and photoluminescence spectrum of the PMVP-5 copolymer prepared in example 5 of the present invention;

FIG. 6 shows confocal laser micrographs of PMVP-1 copolymer prepared in example 1 of the present invention in cell imaging (dark field photograph (left), bright field dark field superposition photograph (center), and bright field photograph (right)).

Detailed Description

The concept and technical effects of the present invention will be clearly and completely described below in conjunction with the embodiments to fully understand the objects, features and effects of the present invention. It is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments, and those skilled in the art can obtain other embodiments without inventive effort based on the embodiments of the present invention, and all embodiments are within the protection scope of the present invention.

In the description of the present invention, reference to the description of the terms "one embodiment," "some embodiments," "an illustrative embodiment," "an example," "a specific example," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

Specific examples of the present invention are described in detail below.

Example 1

This example is a method of preparing a copolymer, comprising the steps of:

s1, preparation of bromolactide:

the L-Lactide (L-Lactide) (28.8g 0.2mol) and N-bromosuccinimide (NBS) (39.15g 0.22mol) were refluxed in benzene for 24h until the Lactide reaction was complete. After the reaction is finished, cooling to room temperature (about 25 ℃), and removing the solvent to obtain a crude product, namely a light yellow solid.

And (3) extracting the crude product light yellow solid by using dichloromethane and 1mol/L sodium thiosulfate solution for one time, then extracting twice by using saturated sodium chloride solution, separating an organic phase, removing the solvent, and recrystallizing by using ethyl acetate to obtain white needle-shaped crystal bromolactide (Br-Lactide).

S2, preparation of methylene allyl lactide:

bromolactide (5.0g) was dissolved in dichloromethane, triethylamine (TEA,2.72g) was added dropwise under nitrogen protection, and the reaction was stirred in an ice-water bath (about 0 ℃ C.) for 2 hours. After the reaction is finished, extracting the reaction solution once by using a 1mol/L dilute hydrochloric acid solution, extracting twice by using a saturated sodium chloride solution, carrying out liquid-liquid separation, collecting an organic phase, concentrating the organic phase, and removing the solvent to obtain a crude product of methylene allyl lactide (MLA). The crude product is purified by column chromatography using the eluent dichloromethane: petroleum ether 1:1(v: v), to give pure MLA monomer.

S3, preparation of methylene allyl lactide- (2-vinylpyridine) copolymer:

adding methylene allyl lactide (0.50g), 2-vinylpyridine (0.07g) and azodiacetonitrile (1.0mg) into a 100mL Schlenk bottle, then adding 10mL of 1, 4-dioxane, freezing, extracting oxygen, reacting at 70 ℃ for 12h, cooling to room temperature, settling, filtering, dissolving the obtained solid into chloroform, removing water, passing through a silica gel column, concentrating again, settling, and obtaining a solid powdery product, wherein the obtained product is PMVP-1;

the structural formula of PMVP-1 is as follows:

wherein x is 110; y is 22.

Example 2

This example is a method of preparing a copolymer, comprising the steps of:

s1, preparation of bromolactide:

the L-Lactide (L-Lactide) (28.8g 0.2mol) and N-bromosuccinimide (NBS) (39.15g 0.22mol) were refluxed in benzene for 24h until the Lactide reaction was complete. After the reaction is finished, cooling to room temperature, and removing the solvent to obtain a crude product, namely a light yellow solid.

And (3) extracting the crude product light yellow solid by using dichloromethane and 1mol/L sodium thiosulfate once, then extracting twice by using a saturated sodium chloride solution, separating an organic phase, removing the solvent, and recrystallizing by using ethyl acetate to obtain white needle-shaped crystal bromolactide (Br-Lactide).

S2, preparation of methylene allyl lactide:

bromolactide (5.0g) was dissolved in dichloromethane, triethylamine (TEA,2.72g) was added dropwise under nitrogen protection, and the reaction was stirred in an ice-water bath for 2 h. After the reaction is finished, extracting the reaction solution once by using a 1mol/L dilute hydrochloric acid solution, extracting twice by using a saturated sodium chloride solution, carrying out liquid-liquid separation, collecting an organic phase, concentrating the organic phase, and removing the solvent to obtain a crude product of the methylene allyl lactide (MLA). The crude product is purified by column chromatography using the eluent dichloromethane: petroleum ether 1:1(v: v), to give pure MLA monomer.

S3, preparation of methylene allyl lactide- (2-vinylpyridine) copolymer:

adding methylene allyl lactide (0.50g), 2-vinylpyridine (0.12g) and azodiacetonitrile (1.0mg) into a 100mL Schlenk bottle, then adding 10mL of 1, 4-dioxane, freezing, extracting oxygen, reacting at 70 ℃ for 12h, cooling to room temperature, settling, filtering, dissolving the obtained solid into chloroform, removing water, passing through a silica gel column, concentrating again, settling, and obtaining a solid powdery product, wherein the obtained product is PMVP-2;

the structural formula of PMVP-2 is as follows:

wherein x is 66; y is 22.

Example 3

This example is a method of preparing a copolymer, comprising the steps of:

s1, preparation of bromolactide:

the L-Lactide (L-Lactide) (28.8g 0.2mol) and N-bromosuccinimide (NBS) (39.15g 0.22mol) were refluxed in benzene for 24h until the Lactide reaction was complete. After the reaction is finished, cooling to room temperature, and removing the solvent to obtain a crude product, namely a light yellow solid.

And (3) extracting the crude product light yellow solid by using dichloromethane and 1mol/L sodium thiosulfate once, then extracting twice by using a saturated sodium chloride solution, separating an organic phase, removing the solvent, and recrystallizing by using ethyl acetate to obtain white needle-shaped crystal bromolactide (Br-Lactide).

S2, preparation of methylene allyl lactide:

bromolactide (5.0g) was dissolved in dichloromethane, triethylamine (TEA,2.72g) was added dropwise under nitrogen protection, and the reaction was stirred in an ice-water bath for 2 h. After the reaction is finished, extracting the reaction solution once by using a 1mol/L dilute hydrochloric acid solution, extracting twice by using a saturated sodium chloride solution, carrying out liquid-liquid separation, collecting an organic phase, concentrating the organic phase, and removing the solvent to obtain a crude product of the methylene allyl lactide (MLA). The crude product is purified by column chromatography using the eluent dichloromethane: petroleum ether 1:1(v: v), to give pure MLA monomer.

S3 preparation of methylene allyl lactide- (2-vinyl pyridine) copolymer

Adding methylene allyl lactide (0.50g), 2-vinylpyridine (0.37g) and azodiacetonitrile (1.0mg) into a 100mL Schlenk bottle, then adding 10mL of 1, 4-dioxane, freezing, extracting oxygen, reacting at 70 ℃ for 12h, cooling to room temperature, settling, filtering, dissolving the obtained solid into chloroform, removing water, passing through a silica gel column, concentrating again, settling, and obtaining a solid powdery product, wherein the obtained product is PMVP-3;

the structural formula of PMVP-3 is as follows:

wherein x is 79; y is 80.

Example 4

This example is a method of preparing a copolymer, comprising the steps of:

s1, preparation of bromolactide:

the L-Lactide (L-Lactide) (28.8g 0.2mol) and N-bromosuccinimide (NBS) (39.15g 0.22mol) were refluxed in benzene for 24h until the Lactide reaction was complete. After the reaction is finished, cooling to room temperature, and removing the solvent to obtain a crude product, namely a light yellow solid.

The crude product is light yellow solid, which is firstly extracted once by dichloromethane and 1mol/L sodium thiosulfate, then extracted twice by saturated sodium chloride solution, an organic phase is separated, the solvent is removed, and recrystallization is carried out by ethyl acetate, thus obtaining white acicular crystal bromolactide (Br-Lactide).

S2, preparation of methylene allyl lactide:

bromolactide (5.0g) was dissolved in dichloromethane, triethylamine (TEA,2.72g) was added dropwise under nitrogen protection, and the reaction was stirred in an ice-water bath for 2 h. After the reaction is finished, extracting the reaction solution once by using a 1mol/L dilute hydrochloric acid solution, extracting twice by using a saturated sodium chloride solution, carrying out liquid-liquid separation, collecting an organic phase, concentrating the organic phase, and removing the solvent to obtain a crude product of the methylene allyl lactide (MLA). The crude product is purified by column chromatography using the eluent dichloromethane: petroleum ether 1:1(v: v), to give pure MLA monomer.

S3, preparation of methylene allyl lactide- (2-vinylpyridine) copolymer:

adding methylene allyl lactide (0.50g), 2-vinylpyridine (0.37g) and azodiacetonitrile (1.0mg) into a 100mL Schlenk bottle, then adding 10mL of 1, 4-dioxane, freezing, extracting oxygen, reacting at 70 ℃ for 12h, cooling to room temperature, settling, filtering, dissolving the obtained solid into chloroform, removing water, passing through a silica gel column, concentrating again, settling, and obtaining a solid powdery product, wherein the obtained product is PMVP-4;

the structural formula of PMVP-4 is as follows:

wherein x is 32; y is 95.

Example 5

This example is a method of preparing a copolymer, comprising the steps of:

s1, preparation of bromolactide:

the L-Lactide (L-Lactide) (28.8g 0.2mol) and N-bromosuccinimide (NBS) (39.15g 0.22mol) were refluxed in benzene for 24h until the Lactide reaction was complete. After the reaction is finished, cooling to room temperature, and removing the solvent to obtain a crude product, namely a light yellow solid.

The crude product is light yellow solid, which is firstly extracted once by dichloromethane and 1mol/L sodium thiosulfate, then extracted twice by saturated sodium chloride solution, an organic phase is separated, the solvent is removed, and recrystallization is carried out by ethyl acetate, thus obtaining white acicular crystal bromolactide (Br-Lactide).

S2, preparation of methylene allyl lactide:

bromolactide (5.0g) was dissolved in dichloromethane, triethylamine (TEA,2.72g) was added dropwise under nitrogen protection, and the reaction was stirred in an ice-water bath for 2 h. After the reaction is finished, extracting the reaction solution once by using a 1mol/L dilute hydrochloric acid solution, extracting twice by using a saturated sodium chloride solution, carrying out liquid-liquid separation, collecting an organic phase, concentrating the organic phase, and removing the solvent to obtain a crude product of the methylene allyl lactide (MLA). The crude product is purified by column chromatography using the eluent dichloromethane: petroleum ether 1:1(v: v), to give pure MLA monomer.

S3, preparation of methylene allyl lactide- (2-vinylpyridine) copolymer:

adding methylene allyl lactide (0.50g), 2-vinylpyridine (0.37g) and azodiacetonitrile (1.0mg) into a 100mL Schlenk bottle, then adding 10mL of 1, 4-dioxane, freezing, extracting oxygen, reacting at 70 ℃ for 12h, cooling to room temperature, settling, filtering, dissolving the obtained solid into chloroform, removing water, passing through a silica gel column, concentrating again, settling, and obtaining a solid powdery product, wherein the obtained product is PMVP-5;

the structural formula of PMVP-5 is as follows:

wherein x is 15; y is 77.

Example 6

This example is the use of a copolymer for cell labeling, comprising the steps of:

s1, cell culture

4T1 cells in exponential growth phase of cell culture were digested into a single-cell liquid with a combination of 0.25% trypsin and 0.02% EDTA, and the single-cell liquid was digested at 1X 10⁵Inoculating at 25 cm/ml density²The culture flask of (1) was cultured in a DMEM medium containing 10% fetal bovine serum at 37 ℃ and 5% CO₂And culturing in a constant temperature incubator.

S2 laser confocal experiment

4T1 cells seeded at log phase at 1X 10⁵cells/well density in the confocal dish, 37 degrees C culture overnight, then add 500 u g/mL samples, incubated for 12h after terminating the culture, PBS washed cells three times, add a certain amount of new PBS, prevent the cells dry out deformation fall off. The samples were observed and photographed under a 40-fold oil-mirror ZEISS LSM 880 confocal microscope.The excitation wavelength is 405nm, and the emission wavelength is 371 nm-585 nm.

The invention is not the best known technology.

The ultraviolet-visible and photoluminescence normalized spectrum of the PMVP-1 solution prepared in the embodiment 1 of the invention is shown in figure 1 (PL represents fluorescence, UV represents ultraviolet); from FIG. 1, it is known that the UV-visible spectrum of PMVP-1 has two characteristic absorptions, wherein the absorption peak of 258nm in the high energy region is attributed to the characteristic absorption of pyridine ring in the polymer, and the absorption peak of 340nm in the low energy region is attributed to the transition absorption of n → π; the photoluminescence spectrum had an emission peak of 399nm and an excitation wavelength of 350 nm.

The ultraviolet-visible and photoluminescence normalized spectrum of the PMVP-2 solution prepared in the embodiment 2 of the invention is shown in figure 2; from FIG. 2, it is known that the UV-visible spectrum of PMVP-2 has two characteristic absorptions, wherein the absorption peak at 258nm in the high energy region is attributed to the characteristic absorption of pyridine ring in the polymer, and the absorption peak at 340nm in the low energy region is attributed to the transition absorption of n → π; the photoluminescence spectrum had an emission peak of 404nm and an excitation wavelength of 350 nm.

The ultraviolet-visible and photoluminescence normalized spectrum of the PMVP-3 solution prepared in the embodiment 3 of the invention is shown in FIG. 3; from FIG. 3, it is known that the UV-visible spectrum of PMVP-3 has two characteristic absorptions, wherein the absorption peak at 2261nm in the high energy region is attributed to the characteristic absorption of pyridine ring in the polymer, and the absorption intensity at about 340nm in the low energy region is greatly reduced due to the reduction of MLA ratio in the polymer; the photoluminescence spectrum had an emission peak of 408nm and an excitation wavelength of 350 nm.

The ultraviolet-visible and photoluminescence normalized spectrum of the PMVP-4 solution prepared in the embodiment 4 of the invention is shown in FIG. 4; from FIG. 4, it is known that the UV-visible spectrum of PMVP-1 has two characteristic absorptions, wherein the absorption peak at 258nm in the high energy region is attributed to the characteristic absorption of pyridine ring in the polymer, and the absorption intensity at about 340nm in the low energy region is greatly reduced due to the reduction of MLA ratio in the polymer; the photoluminescence spectrum had an emission peak of 412nm and an excitation wavelength of 350 nm.

The ultraviolet-visible and photoluminescence normalized spectrum of the PMVP-5 solution prepared in example 5 of the invention is shown in FIG. 5; from FIG. 5, it is known that the UV-visible spectrum of PMVP-5 has two characteristic absorptions, wherein the absorption peak at 261nm in the high energy region is attributed to the characteristic absorption of pyridine ring in the polymer, and the absorption intensity at about 340nm in the low energy region is greatly reduced due to the reduction of MLA ratio in the polymer; the photoluminescence spectrum had an emission peak of 412nm and an excitation wavelength of 350 nm.

The laser confocal pictures of the PMVP-1 copolymer in cell imaging are shown in FIG. 6, dark field picture (FIG. 6 left), bright field dark field superposition picture (FIG. 6 right), and bright field picture (FIG. 6 right). Wherein, the sample is observed and photographed under a 40 times oil lens ZEISS LSM 880 confocal microscope. The excitation wavelength is 405nm, and the emission wavelength range is 371 nm-585 nm; as can be seen from FIG. 6, the PMVP-1 copolymer obtained in example 1 of the present invention realizes cell labeling.

The PMVP-1 to PMVP-5 prepared in the embodiments 1 to 5 of the present invention was added to N, N-dimethylformamide to prepare PMVP-1 to PMVP-5 solutions (the mass concentration of each solution was 0.5mg/mL), and the quantum yield was measured with a Hamamatsu absolute quantum efficiency tester, wherein the excitation wavelength was 350 nm.

Adding the PMVP-1-PMVP-5 prepared in the embodiments 1-5 of the invention into N, N-dimethylformamide to prepare PMVP-1-PMVP-5 solutions (the mass concentration of each solution is 1mg/mL), then dropwise adding the prepared solutions onto a quartz plate of 1cm multiplied by 1cm, and placing the quartz plate on a hot table at 65 ℃ to volatilize the solvent; preparing PMVP-1-PMVP-5 films; the quantum yield was measured in a hamamatsu absolute quantum efficiency tester, in which the excitation wavelength was 350 nm.

The results of the solution quantum yield and the solid film quantum yield of the PMVP-1-PMVP-5 prepared in the embodiments 1-5 of the invention are as follows: wherein the liquid quantum yield of PMVP-1 is 20.6%, and the solid quantum yield is 11.1%; the liquid quantum yield of PMVP-2 was 21.8%, and the solid state quantum yield was 10.5%; the liquid quantum yield of PMVP-3 is 20.5%, and the solid quantum yield is 9.1%; the liquid quantum yield of PMVP-4 was 19.5%, and the solid quantum yield was 3.0%; the liquid quantum yield of PMVP-5 was 20.1%, and the solid state quantum yield was 1.1%.

In conclusion, the copolymer disclosed by the invention has the advantages of relatively wide spectral response and good water solubility; meanwhile, the copolymer has high luminous efficiency in a dilute solution state or a solid state due to the special intramolecular interaction between the methylene allyl lactide and the 2-vinylpyridine, and the luminous intensity and the luminous wavelength of the copolymer can be further adjusted by adjusting the proportion of the methylene allyl lactide to the (2-vinylpyridine); at the same time, the copolymers also have an excitation dependence, which produces different emission wavelengths at different excitation wavelengths. Because the methylene allyl lactide- (2-vinylpyridine) copolymer adopts free radical polymerization, the polymerization method is simple, the cost is low, and the copolymer is a water-soluble luminescent material, and has wide application prospect in the fields of biological/cell imaging, cell marking and the like.

While the embodiments of the present invention have been described in detail with reference to the description and the drawings, the present invention is not limited to the embodiments, and various changes can be made without departing from the gist of the present invention within the knowledge of those skilled in the art. Furthermore, the embodiments of the present invention and the features of the embodiments may be combined with each other without conflict.