CN115590956A - MXene composite material modified by ruthenium complex with photo-thermal and photodynamic synergism, and preparation method and application thereof - Google Patents

Abstract

The invention discloses an MXene composite material modified by a ruthenium complex with photo-thermal and photodynamic synergism, and a preparation method and application thereof. Under the irradiation of light, MXene photothermal effect, ruthenium complex PDT and ultra-thin MXene nanosheet physical cutting cell membrane form a three-in-one synergistic system of physical cutting, photothermal and photodynamic therapy, and the realization of the synergistic system is realized at 150mW/cm ² Low energy density, low concentration of 100 mug/mL and high-efficiency sterilization within a short time of 15-30 min. The preparation method utilizes the condensation of hydroxyl and carboxylThe synthetic reaction is bonded and loaded, the preparation method is simple, complex reaction processes and harsh reaction conditions are not needed, and products can be quickly separated and purified, so that the industrial production is met.

Description

A MXene composite material modified by a ruthenium complex with photothermal and photodynamic synergy and Its preparation method and application

technical field

The invention belongs to the technical field of photothermal and photodynamic materials, and in particular relates to a MXene composite material modified with a ruthenium complex with photothermal and photodynamic synergy, and a preparation method and application thereof.

Background technique

Efforts have been made to address the challenge of bacterial infection and antibiotic resistance, providing many viable options. At this stage, new antibacterial methods include antibacterial agents, low-temperature plasma technology, photocatalytic degradation, photodynamic antibacterial, photothermal antibacterial, etc. The aforementioned several antibacterial methods have limited their application in wound antibacterial due to their own or application defects. And different from antibiotics, photodynamic sterilization relies on the generation of active oxygen, and photothermal sterilization relies on good photothermal effects. It is difficult for bacteria to develop drug resistance, which can effectively avoid the drug resistance crisis caused by the excessive use of antibiotics. Therefore, photodynamic antibacterial and photothermal antibacterial have the advantages of safety, high efficiency, and the ability to prevent bacteria from developing antibiotic resistance, and have recently attracted the attention of researchers.

Photothermal therapy (Photothermal therapy%PTT) is a light-induced method for killing pathogens. The photothermal conversion agent converts light energy into heat energy to make cells and tissues reach a certain temperature and then kill microorganisms. Photodynamic therapy (Photodynamic therapy, PDT) is that photodynamic reagents produce reactive oxygen species (ROS) with strong oxidizing ability under the irradiation of laser light, and rely on their oxidation reaction with protein and DNA to cause cytotoxicity, resulting in protein and DNA deterioration. cause bacterial death. The effect of photodynamic therapy is mainly based on the following three points: photosensitizer (PS), light and oxygen, and the interaction of these three components leads to the generation of reactive oxygen species (ROS). With the continuous development of science and technology, the preparation of nano-scale photosensitizers or loading photosensitizers on nano-materials for sterilization is called nano-photodynamic sterilization technology, which has received extensive attention in recent years. However, the existing photosensitizers are loaded on nanomaterials, and only relying on photosensitizers to sterilize, the bactericidal effect is not obvious. Therefore, the existing PDT materials and PTT materials cannot fully meet the application of photodynamic and photothermal in antibacterial and antitumor applications.

Contents of the invention

In order to overcome the deficiencies of the prior art, the first object of the present invention is to provide a MXene composite material modified with a photothermal and photodynamic synergistic ruthenium complex, which also has the functions of photothermal and photodynamic bacteriostasis and tumor cell killing. The role of photothermal and photodynamic synergistic antibacterial and antitumor, through low energy input, can synergistically and efficiently antibacterial and antitumor.

The second purpose of the present invention is to provide a preparation method of MXene composite material modified by ruthenium complexes with photothermal and photodynamic synergy.

The third object of the present invention is to provide an application of a ruthenium complex-modified MXene composite material with photothermal and photodynamic synergy.

Realize that one of the purposes of the present invention can be achieved by taking the following technical solutions:

A ruthenium complex-modified MXene composite material with photothermal and photodynamic synergy, including a ruthenium complex and a two-dimensional MXene material, the ruthenium complex is loaded on the surface of the two-dimensional MXene material through a covalent bond to form the Ruthenium complex-modified MXene composites with photothermal and photodynamic synergy.

Further, the ruthenium complex has a structure shown in formula I:

为取代或未取代的2，2’-联吡啶，且至少一个

为取代的2，2’-联吡啶；所述取代的2，2’-联吡啶中至少有一个具有式II所示结构：

is a substituted or unsubstituted 2,2'-bipyridine, and at least one

It is a substituted 2,2'-bipyridine; at least one of the substituted 2,2'-bipyridines has the structure shown in formula II:

Wherein R ₁ , R ₂ , R ₃ , R ₄ , R ₅ and R ₆ are any of H, alkyl with 1-3 carbon atoms, halogen or carboxyl, and R ₁ , R ₂ , R ₃ , at least one of R ₄ , R ₅ or R ₆ is a carboxyl group.

Further, the ruthenium complex is

Further, the diameter of the MXene two-dimensional material is less than 500 nm, and the thickness is 1-5 nm.

Two of the goals of the present invention can be achieved by taking the following technical solutions:

A preparation method of an MXene composite material modified by a ruthenium complex with photothermal and photodynamic synergy, comprising the following preparation steps:

The MXene two-dimensional material is dispersed in water to form a dispersion liquid, the ruthenium complex is added to the dispersion liquid, and the ruthenium complex is heated and reacted in an inert gas atmosphere to obtain a MXene composite material modified by the ruthenium complex with photothermal and photodynamic synergy.

Further, the reaction is carried out under a catalyst, and the catalyst is a composite catalyst of carbodiimide salt and 4-dimethylaminopyridine, and the mass ratio of carbodiimide salt and 4-dimethylaminopyridine is 1: (0.5- 2).

Further, the mass ratio of the ruthenium complex to the MXene two-dimensional material is 1:(0.5-2); the temperature of the heating reaction is 80-100°C.

Further, the preparation step of the ruthenium complex is also included:

S11. Preparation of ruthenium precursor: Dissolve substituted or unsubstituted 2,2'-bipyridine, lithium chloride and RuCl ₃ 3H ₂ O in DMF, heat the reaction under an inert gas atmosphere, and cool down to room temperature after the reaction is completed. Gained solid is the ruthenium precursor; the ruthenium precursor has a structure shown in formula III:

S12. Preparation of ruthenium complex: dissolve the ruthenium precursor and substituted or unsubstituted 2,2'-bipyridine in a second solvent, heat the reaction under an inert gas atmosphere, adjust the pH to alkaline, and continue the reaction , the reaction was cooled down to room temperature, and the obtained solid was a ruthenium complex.

Further, the preparation steps of MXene two-dimensional materials are also included:

The MXene base material is etched in situ to obtain a multi-layer MXene aqueous solution with a diameter of 1-10 μm and a thickness of 10-20 nm, and the multi-layer MXene aqueous solution is ultrasonically oscillated for 0.5-5 hours to obtain the MXene two-dimensional material.

Realize the object three of the present invention can reach by taking following technical scheme:

力协同的钌配合物修饰的MXene复合材料或上述任一所述的光热、光动力协同的钌配合物修饰的MXene复合材料的制备方法制备得到的光热、光动力协同的钌配合物修饰的MXene复合材料在制备光热、光动力协同抗菌或抗肿瘤药物中的应用。A kind of above-mentioned any photothermal, photodynamic

The photothermal and photodynamic synergistic ruthenium complex modification prepared by the preparation method of the MXene composite material modified by the ruthenium complex modified by force synergy or any one of the above-mentioned photothermal and photodynamic synergistic ruthenium complex materials The application of MXene composites in the preparation of photothermal and photodynamic synergistic antibacterial or antitumor drugs.

Compared with the prior art, the beneficial effects of the present invention are:

1. The photothermal and photodynamic synergistic ruthenium complex-modified MXene composite material of the present invention connects the MXene two-dimensional material with photothermal effect and the ruthenium complex with photosensitive effect through the condensation reaction of carboxyl and hydroxyl groups, so that Ruthenium complexes are supported on the surface of MXene two-dimensional materials. MXene two-dimensional materials have good near-infrared absorption, good photothermal conversion efficiency and photothermal stability under light, and can be used as photothermal antibacterial and antitumor; ruthenium complexes can be used as photosensitizers to generate ROS under light, which can be used as Photodynamic antibacterial and antitumor substances; therefore, the composite material formed after the MXene two-dimensional material is loaded with ruthenium complexes, the two synergistically antibacterial and antitumor.

2. The preparation method of the photothermal and photodynamic synergistic ruthenium complex-modified MXene composite material of the present invention uses the abundant hydroxyl groups on the surface of the MXene two-dimensional material to carry out condensation reaction with the carboxyl-containing ruthenium complex to realize bond loading. The preparation method It is simple, does not require complex reaction process and harsh reaction conditions, and the product can be quickly separated and purified to meet industrial production.

3. The photothermal and photodynamically synergistic ruthenium complex-modified MXene composite material of the present invention has dual functions of photothermal and photodynamic, and can achieve low energy density (150mW/cm ² ) and low concentration (100μg/ml) , High-efficiency sterilization in a short time (15-30min), so it can be applied in the preparation of photothermal, photodynamic synergistic antibacterial or antitumor drugs.

Description of drawings

Fig. 1 is the mass spectrogram of the ruthenium complex that embodiment 1 prepares;

Fig. 2 is the nuclear magnetic hydrogen spectrogram of the ruthenium complex that embodiment 1 prepares;

Figure 3 is a TEM image of the MXene two-dimensional material prepared in Example 3 and the Ru@MXene prepared in Example 4;

Fig. 4 is the EDS energy spectrum of the MXene two-dimensional material prepared in embodiment 3;

Fig. 5 is the EDS energy spectrum diagram of the Ru@MXene prepared in embodiment 4;

Figure 6 is the XRD pattern of the MXene two-dimensional material prepared in Example 3 and the Ru@MXene composite material prepared in Example 4;

Fig. 7 is the infrared spectrogram of the MXene two-dimensional material prepared in Example 3 and the Ru@MXene composite material prepared in Example 4;

Fig. 8 is the temperature rise curve of the Ru@MXene aqueous suspension prepared in Example 4 with different concentrations along with xenon lamp irradiation;

Fig. 9 is a temperature rise curve of different samples (water, the MXene two-dimensional material prepared in Example 3, the ruthenium complex prepared in Example 1 and the Ru@MXene prepared in Example 4) with xenon lamp irradiation;

Fig. 10 is the thermal infrared diagram of different samples (water, the MXene two-dimensional material prepared in Example 3, the ruthenium complex prepared in Example 1 and the Ru@MXene prepared in Example 4) with xenon lamp irradiation;

Figure 11 is the temperature curve of different samples (water, MXene two-dimensional material prepared in Example 3, ruthenium complex prepared in Example 1 and Ru@MXene prepared in Example 4) during 5 laser on/off cycles picture;

Figure 12 is the absorption change curve at 420nm of the MXene two-dimensional material prepared in Example 3, the ruthenium complex prepared in Example 1, and the Ru@MXene prepared in Example 4 mixed with DPBF under light conditions;

Figure 13 shows the antibacterial effects of the MXene two-dimensional material prepared in Example 3, the ruthenium complex prepared in Example 1, and the Ru@MXene prepared in Example 4 on Escherichia coli under dark and light conditions;

Figure 14 shows the antibacterial effects of different concentrations of Ru@MXene on Escherichia coli under dark and light conditions;

Fig. 15 is the SEM images of the MXene two-dimensional material prepared in Example 3, the ruthenium complex prepared in Example 1 and the Ru@MXene prepared in Example 4 under dark and light conditions.

detailed description

The technical solutions of the present invention will be clearly and completely described below in conjunction with specific embodiments. Apparently, the described embodiments are only some, not all, embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

MXene two-dimensional materials are a new type of nano-two-dimensional sheets of metal carbonitrides. Compared with nano-metal particles (such as nano-silver) and light-sensitive nano-materials (such as ZnO) and other nano-antibacterial materials, MXene two-dimensional materials have With the advantages of good photothermal conversion efficiency and photothermal stability, it has great application prospects in photothermal therapy and drug carriers.

Different from antibiotics, the bactericidal mechanism of MXene two-dimensional materials mainly relies on physical damage and good photothermal effect. Therefore, it is difficult for bacteria to develop drug resistance, which can effectively avoid the drug resistance crisis caused by the overuse of antibiotics. . In particular, targeted or specific bioactive modification of MXene two-dimensional materials will enable MXene two-dimensional materials to have other functions such as targeting and loading, which will improve the biocompatibility of MXene two-dimensional materials and expand Its application in biomedical field such as anti-tumor field.

Ru(II) complexes have strong visible light absorption ability and abundant excited state properties. Among them, Ru(II) complexes with long-lived triplet excited states exhibit strong redox properties, which facilitate intermolecular electron transfer or energy transfer. These properties make them widely used as photosensitizers in PDT.

Ru(II) complexes are widely used in antibacterial and antitumor drugs. Photosensitizers can be combined with nanomaterials in a covalent or non-covalent manner to control the chemical properties of photosensitizers such as solubility, avoid self-quenching between photosensitizers, and improve the generation efficiency of active oxygen; nanomaterials can also change photosensitizers. The in vitro and in vivo behavior of agents, including pharmacokinetics and biodistribution, enhances the selectivity of photosensitizers by enhancing the permeability and retention effect (EPR) or by modifying their surface with targeting ligands.

Therefore, in order to solve the problem of bacterial resistance to antibiotics and the poor therapeutic effect of a single photosensitizer or nanomaterial, the present invention self-assembles the ruthenium complex and the MXene two-dimensional material through surface functional group reactions to form a covalent bond, thereby making the ruthenium complex Loaded onto the surface of MXene two-dimensional materials to form a Ru@MXene nanocomposite system.

A MXene composite material modified by photothermal and photodynamic synergistic ruthenium complexes, including ruthenium complexes and MXene two-dimensional materials, the ruthenium complexes are loaded on the surface of the MXene two-dimensional materials through covalent bonds to form the Ruthenium complex-modified MXene composites with photothermal and photodynamic synergy.

The active oxygen generated by PDT will increase the capture of laser light by photothermal reagents, and the photothermal effect of PTT will increase the oxygen supply of tissues and promote PDT. Forming a system of photothermal therapy and photodynamic therapy of ruthenium complexes synergistically antibacterial and antitumor mechanisms, so that MXene composites can simultaneously achieve combined therapy of PTT and PDT, with excellent controllability, minimal invasiveness, low toxicity and no drug resistance .

In one of the embodiments, the ruthenium complex has the structure shown in formula I:

为带有π共轭结构的含有两个取代或未取代的吡啶环的化合物，其中，两个吡啶环可以直接相连；两个吡啶环可以通过含孤对电子的元素连接；两个吡啶环还可以通过与环基团形成稠环相连；其中式I中三个

可以相同也可以不同，但至少有一个

上含有至少一个羧基。In one of these embodiments,

It is a compound containing two substituted or unsubstituted pyridine rings with a π-conjugated structure, wherein the two pyridine rings can be directly connected; the two pyridine rings can be connected through an element containing a lone pair of electrons; the two pyridine rings can also be Can be connected by forming a fused ring with a ring group; wherein three in formula I

can be the same or different, but at least one

contain at least one carboxyl group.

为取代或未取代的2，2’-联吡啶，且至少一个

为取代的2，2’-联吡啶；所述取代的2，2’-联吡啶中至少有一个具有式II所示结构：preferred,

is a substituted or unsubstituted 2,2'-bipyridine, and at least one

It is a substituted 2,2'-bipyridine; at least one of the substituted 2,2'-bipyridines has the structure shown in formula II:

Wherein R ₁ -R ₆ is any one of H, alkyl with 1-3 carbon atoms, halogen, and carboxyl, and at least one of R ₁ -R ₆ is carboxyl.

2,2'-bipyridine coordinates with ruthenium, and the six N atoms of the three 2,2'-bipyridines are located in relatively symmetrical positions, so the formed ruthenium complex has a relatively compact and stable structure, and when used as a photosensitizer It has good stability and can realize better photodynamic force.

In one of the embodiments, the number of carboxyl groups in the ruthenium complex is two, which are located at the 4 and 4' positions of the same 2,2'-bipyridine.

A ruthenium complex formed by 2,2'-bipyridine, in which the two carboxyl groups contained in the 4 and 4' positions of 2,2'-bipyridine are located on the same side of 2,2'-bipyridine, and have relatively consistent bonds Therefore, after condensation with the hydroxyl groups on the surface of the MXene two-dimensional material, it has less steric hindrance and less force to form a stable composite structure.

In one of the embodiments, the ruthenium complex is

In one embodiment, the diameter of the MXene two-dimensional material is less than 500 nm, and the thickness is 1-5 nm.

Wherein, the MXene two-dimensional material is a known material; preferably, the MXene two-dimensional material is Ti ₃ C ₂ , Ti ₂ C, Nb ₂ C, V ₂ C, (Ti _0.5 Nb _0.5 ) ₂ C, (V Any one of _0.5 Cr _0.5 ) ₃ C ₂ , Ti ₃ CN and Ta ₄ C ₃ . More preferably, the MXene two-dimensional material is Ti ₃ C ₂ .

The diameter of the MXene two-dimensional material is less than 500nm, and the thickness is 1-5nm. On the one hand, it can be loaded and modified by a ruthenium complex, and has a large specific surface; on the other hand, the MXene two-dimensional material of this size is loaded with a ruthenium complex Finally, it can be transferred in the human body, and can effectively accumulate on the surface of bacteria or cells for sufficient contact, and can play a role through photothermal and photosensitive.

The present invention also provides a method for preparing an MXene composite material modified by a photothermal and photodynamic synergistic ruthenium complex, comprising the following preparation steps:

The MXene two-dimensional material is dispersed in water to form a dispersion liquid, the ruthenium complex is added to the dispersion liquid, and the ruthenium complex is heated and reacted in an inert gas atmosphere to obtain a MXene composite material modified by the ruthenium complex with photothermal and photodynamic synergy.

There are hydrophilic active groups such as hydroxyl groups and carbonyl groups on the surface of MXene two-dimensional materials. Through chemical reaction or physical adsorption on these active groups, the modification of MXene two-dimensional materials can be effectively realized, and the functions of MXene two-dimensional materials can be realized. After modification, its water dispersibility can be better improved, which is conducive to its dispersion in the physiological environment.

Therefore, the present invention uses a ruthenium complex containing a carboxyl group. The carboxyl group on the ruthenium complex is condensed with the hydroxyl group on the surface of the MXene two-dimensional material to form a load. This reaction is a conventional carboxyl group and hydroxyl group in the art. Synthetic ester reaction, so no complicated process and harsh reaction conditions are required.

In one of the embodiments, the reaction is carried out under a catalyst, the catalyst is a composite catalyst of carbodiimide salt and 4-dimethylaminopyridine, and the mass ratio of carbodiimide salt and 4-dimethylaminopyridine is 1 : (0.5-2).

After the carboxyl group is activated by the carbodiimide salt, under the catalysis of the catalyst 4-dimethylaminopyridine, the condensation reaction of the carboxyl group and the hydroxyl group to form an ester can be promoted, and the yield can be significantly increased. Preferably, the carbodiimide salt is 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDCI), which can be dissolved in water with 4-dimethylaminopyridine (DMAP). It is a permanent composite catalyst without the need to introduce organic solvents, which simplifies post-processing and composite green chemistry requirements.

In one embodiment, the mass ratio of the ruthenium complex to the MXene two-dimensional material is 1:(0.5-2); the reaction temperature is 80-100°C.

In one of the embodiments, the preparation step of the ruthenium complex is also included:

S11. Preparation of ruthenium precursor: Dissolve substituted or unsubstituted 2,2'-bipyridyl with lithium chloride and RuCl ₃ 3H ₂ O in DMF, condense and reflux for 8-36 hours under an inert gas atmosphere, and the reaction is completed to At room temperature, the solid obtained is the ruthenium precursor; the ruthenium precursor has a structure shown in formula III:

S12. Preparation of ruthenium complex: the ruthenium precursor and substituted or unsubstituted 2,2'-bipyridine are dissolved in a second solvent, heated and reacted in an inert gas atmosphere, and the pH is adjusted to alkaline, and then the reaction is continued. After the reaction was completed, the temperature was lowered to room temperature, and the obtained solid was a ruthenium complex.

In one embodiment, the molar mass ratio of substituted or unsubstituted 2,2'-bipyridyl, lithium chloride and RuCl ₃ ·3H ₂ O in step S11 is (1.7-2.2):(2.2-3.5): 1; the first solvent is DMF, and the volume of DMF is 10-30mL; the reaction condition in step S11 is reflux reaction for 6-24h.

In one embodiment, the molar mass ratio of the ruthenium precursor to the substituted or unsubstituted 2,2'-bipyridine in step S12 is 1:(1.2-2); the second solvent is absolute ethanol The volume of absolute ethanol is 50mL; the reaction condition in step S12 is reflux reaction for 8-36h; the pH is adjusted to alkaline with NaOH.

In one embodiment, the inert gas atmosphere is nitrogen or argon atmosphere, preferably argon atmosphere.

In one of the embodiments, the preparation steps of MXene two-dimensional materials are also included:

The MXene base material is etched in situ to obtain a multi-layer MXene aqueous solution with a diameter of 1-10 μm and a thickness of 10-20 nm, and the multi-layer MXene aqueous solution is ultrasonically oscillated for 0.5-5 hours to obtain the MXene two-dimensional material.

The present invention also provides a MXene composite material modified by any of the above-mentioned photothermal and photodynamic synergistic ruthenium complexes or any of the above-mentioned photothermal and photodynamic synergistic ruthenium complex modified MXene composite materials prepared by the preparation method Application of photothermal and photodynamic synergistic ruthenium complex modified MXene composites in the preparation of photothermal, photodynamic synergistic antibacterial or antitumor drugs.

Embodiment 1: preparation ruthenium complex

1.8 g of 2,2'-bipyridine (bpy), 0.7 g of lithium chloride and 1.56 g of RuCl ₃ ·3H ₂ O were dissolved in 10 mL of N,N-dimethylformamide (DMF), and then Under the protection of argon atmosphere, it was condensed and refluxed at 140°C for 12h. After suction filtration, recrystallization, and vacuum drying, dark green microcrystals were obtained as ruthenium precursor cis-[Ru(bpy) ₂ Cl ₂ ]·2H ₂ O;

Dissolve 0.52g of ruthenium precursor cis-[Ru(bpy) ₂ Cl ₂ ]·2H ₂ O in absolute ethanol, then add 0.3g of 2,2'-bipyridine-4,4'-dicarboxylic acid ( dcb), under the protection of argon atmosphere, heated to 80°C and refluxed, adjusted the pH to alkaline with NaOH, continued to reflux for 12 hours after dissolving, adjusted the pH with HCI after the reaction was completed, and removed the solvent by rotary evaporation under reduced pressure to obtain an orange-red solid It is a ruthenium complex [Ru(bpy) ₂ (dcb)] ²⁺ .

Embodiment 2: preparation ruthenium complex

Dissolve 2.5g of 2,2'-bipyridine-4,4'-dimethyl, 0.9g of lithium chloride and 1.56g of RuCl ₃ ·3H ₂ O in 30mL of DMF, and then under the protection of argon atmosphere Condensation reflux 6h. Through suction filtration, recrystallization, repeated purification and drying, the ruthenium precursor is obtained;

Dissolve 0.52g of ruthenium precursor in absolute ethanol, then add 0.22g of 2,2-bipyridine-4,4'-dicarboxylic acid, heat to reflux under the protection of argon atmosphere, adjust the pH to alkali with NaOH After the dissolution, continue to reflux for 8 hours. After the reaction, adjust the pH with HCI, and remove the solvent by rotary evaporation under reduced pressure to obtain a solid that is a ruthenium complex.

Embodiment 3: preparation ruthenium complex

1.62g of 2,2'-bipyridyl, 0.57g of lithium chloride and 1.56g of RuCl ₃ ·3H ₂ O were dissolved in 20mL of DMF, and then condensed and refluxed at 140°C for 24h under the protection of argon atmosphere. After suction filtration, recrystallization, and vacuum drying, the ruthenium precursor is obtained;

Dissolve 0.52g of ruthenium precursor in absolute ethanol, then add 0.33g of 2,2-bipyridine-4-carboxylic acid, heat to reflux under the protection of argon atmosphere, adjust the pH to alkaline with NaOH, and dissolve Continue to reflux for 36 h, adjust the pH with HCl after the reaction, and remove the solvent by rotary evaporation under reduced pressure to obtain a solid that is a ruthenium complex.

Example 4: Preparation of MXene two-dimensional material (Ti ₃ C ₂ T _x )

Weigh 3g of lithium fluoride powder, add 40mL of 12M concentrated hydrochloric acid, stir evenly, add 2g of Ti ₃ AlC ₂ base material to it, stir at 40°C for two days, and obtain pure multilayer Ti by washing with water and ethanol ₃ C ₂ T _x material. Disperse the multi-layer Ti ₃ C ₂ T _x material in a book, vibrate vigorously at room temperature and ultrasonicate for 3 hours to obtain an aqueous suspension of few-layer Ti ₃ C ₂ T _x two-dimensional nanomaterials, and freeze-dry to obtain Ti ₃ C ₂ T _x Two-dimensional nanomaterials.

Example 5: Preparation of materials Ru@MXene

Add 0.1 g of the ruthenium complex [Ru(bpy) ₂ (dcb)] ²⁺ prepared in Example 1 to the suspension containing 0.1 g of Ti ₃ C ₂ T _x two-dimensional nanomaterials, and add a mass ratio of 1: 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDCI) and 0.005g of water-soluble composite catalyst composed of 4-dimethylaminopyridine (DMAP) mix homogeneously, in React in an inert gas atmosphere at 100°C for 3 hours, centrifuge after the reaction, remove the supernatant, wash the residue repeatedly with deionized water, and freeze-dry to obtain the MXene composite material modified by the photothermal and photodynamic synergistic ruthenium complex. Denoted as Ru@MXene.

Embodiment 6: prepare composite material

Add 0.05 g of the ruthenium complex prepared in Example 2 to the suspension containing 0.1 g of Ti ₃ C ₂ T _x two-dimensional nanomaterials, and then add 1-(3-dimethylaminopropyl with a mass ratio of 1:1 )-3-ethylcarbodiimide hydrochloride (EDCI) and 4-dimethylaminopyridine (DMAP) water-soluble composite catalyst 0.01g mixed uniformly, reacted for 1h under inert gas atmosphere at 100°C, after the reaction After centrifugation, the supernatant was removed, and the residue was repeatedly centrifuged and washed with deionized water, and then freeze-dried to obtain the photothermal and photodynamic synergistic ruthenium complex-modified MXene composite.

Embodiment 7: prepare composite material

Add 0.2 g of the ruthenium complex prepared in Example 3 to the suspension containing 0.1 g of Ti ₃ C ₂ T _x two-dimensional nanomaterials, and then add 1-(3-dimethylaminopropyl with a mass ratio of 1:1 )-3-ethylcarbodiimide hydrochloride (EDCI) and 4-dimethylaminopyridine (DMAP) water-soluble composite catalyst 0.012g mixed uniformly, reacted for 12h under inert gas atmosphere 100 ℃, after the reaction After centrifugation, the supernatant was removed, and the residue was repeatedly centrifuged and washed with deionized water, and then freeze-dried to obtain the photothermal and photodynamic synergistic ruthenium complex-modified MXene composite.

Test case:

1. The ruthenium complex [Ru(bpy) ₂ (dcb)] ²⁺ prepared in Example 1 is subjected to mass spectrometry and nuclear magnetic analysis, the results are shown in Figure 1 and Figure 2, wherein, ESI-MS (CH ₃ OH) : m/z: 329.04[M] ²⁺ , thus M is 658.08, which is almost consistent with the relative molecular weight of 657.65. The results obtained by nuclear magnetic analysis are: ¹ H NMR (400MHz, DMSO) δ8.85 (d, J=8.2Hz, 4H), 8.79 (s, 2H), 8.15 (dd, J=13.0, 6.6Hz, 4H), 7.74 (d, J=5.4Hz, 6H), 7.66 (d, J=5.7Hz, 2H), 7.53 (t, J=6.7Hz, 4H), it is proved that the obtained ruthenium complex is [Ru(bpy) ₂ ( dcb)] ²⁺ .

2. Observe the MXene two-dimensional material Ti ₃ C ₂ T _x prepared in Example 4 and the Ru@MXene prepared in Example 5 under TEM. The TEM image is shown in Figure 3, and the figure on the right is Example 4 The TEM image of the prepared MXene two-dimensional material Ti ₃ C ₂ T _x , the left image is the TEM image of Ru@MXene prepared in Example 5. The EDS energy spectrum is shown in Figure 4 and Figure 5, where Figure 4 is the EDS energy spectrum of the MXene two-dimensional material Ti ₃ C ₂ T _x prepared in Example 4, and Figure 5 is the Ru@MXene prepared in Example 5 The EDS energy spectrum.

It can be seen from Figure 3 that the MXene two-dimensional material Ti ₃ C ₂ T _x is in the shape of two-dimensional flakes, and the Ru@MXene material formed after modification with ruthenium complexes is still in the shape of flakes, with a size of about 200nm.

It can be seen from Figure 4 that the MXene two-dimensional material Ti ₃ C ₂ T _x contains Ti, O, Cl, F, and c elements, while Ru@MXene in Figure 5 has new elements N and Ru, which proves that the surface of MXene is successfully covered by Ru-containing substances. load.

3. The MXene two-dimensional material Ti ₃ C ₂ T _x prepared in Example 4 and the Ru@MXene prepared in Example 5 were subjected to XRD detection, and the XRD pattern is shown in FIG. 6 .

In Figure 6, the (002) peak of Ru@MXene shifted to a lower angle by 0.91°, corresponding to the significant increase in the interlayer space between the Ru@MXene sheets and the formation of ultrathin nanosheet structures , which is conducive to the physical cutting of cell membranes by ultrathin nanosheets, thereby improving the antibacterial or antitumor efficiency.

4. The MXene two-dimensional material Ti ₃ C ₂ T _x prepared in Example 4 and the Ru@MXene prepared in Example 5 were respectively subjected to infrared spectrum testing, and the infrared spectrum testing chart is shown in FIG. 7 .

In Figure 7, the MXene two-dimensional materials Ti ₃ C ₂ T _x and Ru@MXene both show typical characteristic bands at 3431cm ^-1 , 1632cm ^-1 and 562cm ^-1 , corresponding to -OH, C=O and Ti- The stretching vibration of O. Among them, Ru@MXene modified by ruthenium complexes has absorption bands related to ester bonds at 1088 cm ^-1 and 1049 cm ^-1 , indicating that the hydroxyl groups on the ruthenium complexes and the MXene two-dimensional material Ti ₃ C ₂ T _x The hydroxyl groups were successfully esterified, and the ruthenium complexes were supported on the MXene two-dimensional material Ti ₃ C ₂ T _x nanosheets.

Test example:

1. Photothermal heating efficiency:

The Ru@MXene prepared in Example 5 was dispersed in water, prepared into dispersions with different mass concentrations, irradiated with a xenon lamp (laser power density: 1.5sun), and obtained different concentrations (0 μg/ mL, 20 μg/mL, 50 μg/mL and 100 μg/mL) of the temperature curve of Ru@MXene, the temperature curve is shown in Figure 8.

It can be seen from Figure 8 that at a lower mass concentration (100 μg/mL) of Ru@MXene, the solution temperature can reach 53 °C after 15 minutes of irradiation, indicating that Ru@MXene can efficiently and quickly convert light into heat energy, and at the same time The concentration dependence of the photothermal performance of Ru@MXene was verified.

Take the aqueous solution of the ruthenium complex prepared in Example 1 with the same mass concentration of the same volume, the aqueous dispersion of the MXene two-dimensional material Ti ₃ C ₂ T _x prepared in Example 4, and the Ru@MXene prepared in Example 5 Dispersed in water, dissolved in water, irradiated with a xenon lamp (laser power density: 1.5sun), and obtained a temperature curve using an infrared thermal imager. The temperature curve is shown in Figure 9, and the thermal infrared image is shown in Figure 10.

In Fig. 9-10, different samples: water, ruthenium complex, MXene two-dimensional material Ti ₃ C ₂ T _x , Ru@MXene) aqueous solution under the irradiation of xenon lamp, in which MXene two-dimensional material Ti ₃ C ₂ T _x and Ru Under the irradiation of xenon lamp, the solution temperature of @MXene reached close to 53°C within 15 minutes, while the temperature of the sample water was only 38°C, indicating that both MXene two-dimensional materials Ti ₃ C ₂ T _x and Ru@MXene nanosheets have good photothermal properties performance.

2. Light and heat stability:

Take the aqueous solution of the ruthenium complex prepared in Example 1 with the same mass concentration of the same volume, the aqueous dispersion of the MXene two-dimensional material Ti ₃ C ₂ T _x prepared in Example 4, and the Ru@MXene prepared in Example 5 Dispersed in water, dissolved in water, irradiated with a xenon lamp (laser power density: 1.5 sun), using an infrared thermal imager to obtain a temperature curve with an irradiation time of 5 laser on/off cycles, the temperature curve is shown in Figure 11.

The photothermal performance of Ru@MXene did not deteriorate significantly during the whole process, indicating its good photothermal stability.

3. In vitro photodynamic activity:

Using the diphenylisobenzofuran (DPBF) singlet oxygen indicating fluorescent probe as a probe, measure the total ROS generated by the sample under the irradiation of a 532nm LED green light; the samples are respectively: the ruthenium complex prepared in Example 1, the ruthenium complex prepared in Example 4 Prepared MXene two-dimensional material Ti ₃ C ₂ T _x , Ru@MXene prepared in Example 5, and water, as follows:

In a quartz cuvette, 2.97 mL of the ruthenium complex prepared in Example 1, the MXene two-dimensional material Ti ₃ C ₂ T _x prepared in Example 4, the Ru@MXene prepared in Example 5, Water was stirred and mixed with 30 μL of DMSO solution of DPBF at a concentration of 10 mM; then irradiated with a 532 nm LED green light of 20 mW, and the irradiation period was 5 min. During this process, at a preset time point, an ultraviolet spectrophotometer was used to record the absorbance of DPBF at 420 nm, and the change curve of the absorbance is shown in FIG. 12 .

In Fig. 12, when the ruthenium complex solution alone is irradiated with 532nm LED green light, the absorbance of DPBF at 420nm decreases rapidly, producing a large amount of ¹ O ₂ , while the DPBF absorbance change in the Ru@MXene solution has no ruthenium complex alone Obviously, more ¹ O ₂ is still produced, and the DPBF absorbance of the single MXene two-dimensional material Ti ₃ C ₂ T _x solution has almost no change; it shows that Ru@MXene has a good photodynamic effect after loading the ruthenium complex .

4. Bactericidal activity of Ru@MXene

(1) Bacterial solution preparation: Pick a single colony of E. coli with an inoculation loop and put it in 10 mL of LB culture medium, place it in a shaker at 37°C and 220 r/min and cultivate it until the OD600 of the bacterial solution is between 0.5 and 0.6, measure the OD value, and dilute to 0.01 (the concentration of bacteria solution is 10 ⁷ CFU/mL), set aside.

(2) Configuration samples: respectively configure the aqueous solution of the ruthenium complex of Example 1 with a mother liquor of 30 μM, the MXene two-dimensional material Ti ₃ C ₂ T _x aqueous dispersion of 5 mg/mL of Example 3, and the Ru@ of Example 4 of 5 mg/mL MXene aqueous dispersion.

Take several EP tubes, and prepare each bacteria as follows:

Sample 1) Bacteria: Add 50 μL of bacterial solution and 450 μL of sterile water;

Sample 2) bacteria + ruthenium complex of Example 1: add 50 μL of bacterial liquid, 250 μL of 30 μM ruthenium complex solution of Example 1 and 200 μL of sterile water, and the final concentration of the ruthenium complex of Example 1 in the solution is 15 μM.

Sample 3) Bacteria + the MXene two-dimensional material Ti ₃ C ₂ T _x of Example 3: add 50 μL of bacterial solution, 5 mg/mL of the MXene two-dimensional material Ti ₃ C ₂ T _x aqueous dispersion of Example 3 10 μL and 440 μL of sterile Water, the final concentration of the MXene two-dimensional material Ti ₃ C ₂ T _x of Example 3 in the solution is 100 μg/ml; the final concentration of the MXene two-dimensional material Ti ₃ C ₂ T _x of Example 3 is configured in the same way as 20 μg/ml ml, 50 μg/ml, 200 μg/ml of 500 μL solution containing 50 μL bacterial solution.

Sample 4) Bacteria + Ru@MXene of Example 4: Add 50 μL of bacterial liquid, 10 μL of 5 mg/mL Ru@MXene aqueous dispersion of Example 4 and 440 μL of sterile water, and the final concentration of Ru@MXene of Example 4 in the solution is 100 μg/ml.

5) The configured sample 1) bacteria; sample 2) bacteria + the ruthenium complex of Example 1; sample 3) bacteria + the MXene two-dimensional material Ti ₃ C ₂ T _x of Example 3 with a final concentration of 100 μg/ml ; Ru@MXene of sample 4) bacterium+embodiment 4 is detection sample. Each test sample is treated with two groups of light and no light at the same time; the light treatment condition is a xenon lamp with a wavelength range of 300-2500nm and a light intensity of 1.50Sun for 30min;

Note: Light intensity density 1Sun=100mw/cm ² .

6) The configured sample 1) bacteria; sample 3) medium bacteria + the MXene two-dimensional material Ti ₃ C ₂ T _x of Example 3 with a final concentration of 20 μg/ml; sample 3) medium bacteria + a final concentration of 50 μg/ml The MXene two-dimensional material Ti ₃ C ₂ T _x of Example 3; sample 3) medium bacteria + the final concentration of the MXene two-dimensional material Ti ₃ C ₂ T _x of Example 3 of 100 μg/ml; sample 3) medium bacteria + The MXene two-dimensional material Ti ₃ C ₂ T _x of Example 3 with a final concentration of 200 μg/ml was used as a test sample. Each test sample was treated with two groups of light and no light at the same time; the light treatment condition was a xenon lamp with a wavelength range of 300-2500nm and irradiated with a light intensity of 1.50Sun for 30min.

7) Colony plate culture: take 100 μL of samples from each group in step 6) and spread on the agar plate. Place it in a 37°C incubator, cultivate for 18-24 hours, observe the results, and record the data; the results are shown in Figure 13.

8) Colony plate culture: Take 100 μL of samples from each group in step 5) and spread them on an agar plate. Place it in a 37°C incubator, culture for 18-24 hours, observe the results, and record the data; the results are shown in Figure 14.

(3) Plate culture results

Bactericidal effect of Ru@MXene induced by light in different samples.

As shown in Figure 13, the plate culture results show that this method is irradiated under a xenon lamp with a light intensity of 1.5 Sun for 30 minutes, 15 μM of the ruthenium complex of Example 1, and 100 μg/mL of the MXene two-dimensional material Ti ₃ C ₂ T _x of Example 3 , 110 μg/mL of Ru@MXene in Example 4, the concentration of each group of Escherichia coli was significantly lower than that of the sample 1) pure bacteria group; while the Ru@MXene of Example 4 was significantly lower than the MXene of Example 3 The bactericidal effect of the two-dimensional material Ti ₃ C ₂ T _x single action group and the ruthenium complex of Example 1 single action group is good.

The samples cultured on the above plates were observed by SEM, and the results are shown in FIG. 15 .

As can be seen from the SEM images in Figure 15, Ru@MXene aggregated on the bacterial surface and destroyed the cell wall. Light stimulates the ruthenium complex to generate reactive oxygen species, destroying the cell wall structure, and at the same time, Ru@MXene converts light energy into heat energy, which increases the temperature of the tissue in the bacteria, leaks the cell contents, and eventually leads to the death of the bacteria.

The functional modification of MXene two-dimensional materials can better improve its water dispersibility, which is conducive to its dispersion in physiological environments. In the Ru@MXene composite system, the active oxygen generated by the ruthenium complex will increase the laser capture of the photothermal material MXene, and the photothermal effect of MXene will increase the oxygen supply of the tissue and promote the generation of PDT of the ruthenium complex. Ru@MXene also has ultra-thin MXene nanosheets to physically cut cell membranes, photothermal therapy and ruthenium complex photodynamic therapy, realizing a three-in-one synergistic antibacterial mechanism.

The bactericidal effect of Ru@MXene was induced by light under different concentrations of Ru@MXene.

As shown in Figure 14, with the increase of Ru@MXene concentration in Example 4, the bacterial concentration under dark conditions did not change significantly, and the bacterial concentration showed a downward trend after light irradiation, so the Ru@MXene sterilization of the present invention showed that Ru@MXene Concentration dependent effect. When the concentration of Ru@MXene reaches 50 μg/ml, the Ru@MXene of the present invention shows obvious inhibitory effect on Escherichia coli, and the antibacterial effect becomes stronger as the concentration increases.

In summary, the present invention reacts the ruthenium complex and MXene to form a covalent bond through the surface functional group, loads the ruthenium complex on the surface of MXene, and forms a Ru@MXene nanocomposite material. Under the light, the reactive oxygen species produced by the ruthenium complex will increase the capture of laser light by the photothermal material MXene, and the photothermal effect of MXene will increase the oxygen supply of the tissue and promote the generation of PDT of the ruthenium complex. At the same time, the ultra-thin MXene nanosheets can also physically cut the cell membrane, forming a three-in-one synergistic antibacterial and anti-tumor mechanism system of physical cutting, photothermal therapy and ruthenium complex photodynamic therapy, which provides a new alternative to antibiotic therapy and tumor drug therapy. train of thought.

The above-mentioned embodiment is only a preferred embodiment of the present invention, and cannot be used to limit the protection scope of the present invention. Any insubstantial changes and substitutions made by those skilled in the art on the basis of the present invention belong to the scope of the present invention. Scope of protection claimed.

Claims (10)

1. The MXene composite material modified by the ruthenium complex with photo-thermal and photodynamic synergy is characterized by comprising the ruthenium complex and an MXene two-dimensional material, wherein the ruthenium complex is loaded on the surface of the MXene two-dimensional material through a covalent bond to form the MXene composite material modified by the ruthenium complex with photo-thermal and photodynamic synergy.

2. The MXene composite material modified by the photothermal and photodynamic cooperative ruthenium complex according to the claim 1,

the ruthenium complex has a structure shown in formula I:

is substituted or unsubstituted 2,2' -bipyridine, and at least one

Is substituted 2,2' -bipyridine; at least one of the substituted 2,2' -bipyridines has the structure shown in formula II:

wherein R is ₁ 、R ₂ 、R ₃ 、R ₄ 、R ₅ And R ₆ Is any one of H, alkyl with 1-3 carbon atoms, halogen or carboxyl, and R ₁ 、R ₂ 、R ₃ 、R ₄ 、R ₅ Or R ₆ At least one is a carboxyl group.

3. The MXene composite material modified by the photothermal and photodynamic cooperative ruthenium complex according to claim 1 or 2, wherein the ruthenium complex is

4. The MXene composite material modified by the photothermal and photodynamic synergistic ruthenium complex as claimed in claim 1, wherein the MXene two-dimensional material has a diameter of less than 500nm and a thickness of 1-5nm.

5. The preparation method of the MXene composite material modified by the photothermal and photodynamic synergistic ruthenium complex as claimed in any one of claims 1 to 4, is characterized by comprising the following preparation steps: and dispersing the MXene two-dimensional material into water to form a dispersion liquid, adding the ruthenium complex into the dispersion liquid, and heating and reacting under an inert gas atmosphere to obtain the MXene composite material modified by the ruthenium complex with photo-thermal and photodynamic synergism.

6. The method for preparing the MXene composite material modified by the ruthenium complex with photo-thermal and photo-dynamic synergy as claimed in claim 5, wherein the ruthenium complex is a mixture of ruthenium complex and MXene complex,

the reaction is carried out under the catalyst which is a composite catalyst of carbodiimide salt and 4-dimethylaminopyridine, and the mass ratio of the carbodiimide salt to the 4-dimethylaminopyridine is 1: 0.5-2.

7. The method for preparing the MXene composite material modified by the ruthenium complex with photo-thermal and photo-dynamic synergy according to claim 5,

the mass ratio of the ruthenium complex to the MXene two-dimensional material is 1: 0.5-2; the temperature of the heating reaction is 80-100 ℃.

8. The method for preparing the MXene composite material modified by the ruthenium complex with photo-thermal and photo-dynamic synergy as claimed in claim 5, further comprising the step of preparing the ruthenium complex:

s11, ruthenium precursor preparation: mixing 2,2' -bipyridine, lithium chloride and RuCl ₃ Dissolving 3H2O in a first solvent, heating to react under an inert gas atmosphere, and cooling to room temperature after the reaction is finished, wherein the obtained solid is the ruthenium precursor; the ruthenium precursor has a structure represented by formula III:

s12, preparing a ruthenium complex: and dissolving the ruthenium precursor and substituted or unsubstituted 2,2' -bipyridine in a second solvent, heating to react under the atmosphere of inert gas, adjusting the pH value to be alkaline, continuing to react, and cooling to room temperature after the reaction is finished to obtain a solid ruthenium complex.

9. The method for preparing the MXene composite material modified by the ruthenium complex with the photo-thermal and photodynamic coordination function as claimed in claim 5, further comprising the steps of:

the MXene two-dimensional material is obtained by carrying out in-situ etching on a base material of the MXene to obtain a multilayer MXene aqueous solution with the diameter of 1-10 mu m and the thickness of 10-20nm, and carrying out ultrasonic oscillation on the multilayer MXene aqueous solution for 0.5-5 h.

10. An application of the MXene composite material modified by the ruthenium complex with the photo-thermal and photodynamic coordination function as defined in any one of claims 1 to 4 or the MXene composite material modified by the ruthenium complex with the photo-thermal and photodynamic coordination function as defined in any one of claims 5 to 9 in preparation of a photo-thermal and photodynamic coordination antibacterial or antitumor drug.

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