ZIF-8 composite material loaded with SSZ and ICG as well as preparation method and application of ZIF-8 composite material
By preparing ZIF-8 composite materials loaded with SSZ and ICG, the problems of poor selectivity of chemotherapy drugs and insufficient photothermal therapy depth were solved, realizing the synergistic effect of chemotherapy and photothermal therapy, significantly enhancing cytotoxicity to breast cancer cells, improving drug loading efficiency and structural stability, and simplifying the preparation process.
Patent Information
- Application Number
- CN202510937127.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-08
- Publication Date
- 2025-10-31
AI Technical Summary
Existing chemotherapy drugs have poor selectivity, significant side effects, and are prone to drug resistance. Single photothermal therapy is insufficient in depth. Existing nanomedicine delivery systems have low drug encapsulation efficiency and difficult-to-control release rates. ICG is easily degraded under physiological conditions. Most systems lack reasonable synergistic design. ZIF-8 has limited room for improvement in multi-drug synergistic delivery and photothermal therapy functions.
ZIF-8 composites loaded with SSZ and ICG were prepared by a co-solution method. ZIF-8 nanoparticles loaded with SSZ and ICG were generated by mixing sulfasalazine and indocyanine green with zinc nitrate hexahydrate. After centrifugation and washing, the composite material was obtained. The acid-environment responsiveness of ZIF-8 was used to achieve the specific release of drugs in tumor tissues.
It achieves a synergistic effect of chemotherapy and photothermal therapy, significantly enhances cytotoxicity against breast cancer cells, improves drug loading efficiency and structural stability, reduces ICG degradation, simplifies the preparation process, and has good potential for large-scale production.
Smart Images
Figure CN120860245A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of nanomedicine, specifically relating to ZIF-8 composite materials loaded with SSZ and ICG, their preparation methods, and applications. Background Technology
[0002] Breast cancer treatment primarily includes surgery, chemotherapy, radiotherapy, and targeted therapy. However, traditional chemotherapy methods have significant limitations, such as poor drug selectivity, severe side effects, and the development of drug resistance, which seriously restricts the improvement of treatment efficacy. In recent years, photothermal therapy (PTT) has received widespread attention due to its advantages such as minimal invasiveness, high controllability, and significant killing effect on tumor cells. However, single photothermal therapy still faces problems such as insufficient treatment depth and uneven local temperature rise, resulting in limited efficacy in practical applications. Therefore, developing a nanomedicine delivery system that combines the functions of chemotherapy and photothermal therapy, with good targeting and biocompatibility, has become an urgent technical challenge to be solved.
[0003] In existing technologies, materials such as liposomes and polymer nanoparticles are widely used in tumor drug delivery, but they suffer from drawbacks such as low drug encapsulation efficiency and difficulty in controlling release rates. To achieve synergistic effects in multimodal therapy, some studies have attempted to combine chemotherapeutic drugs with photothermal agents such as indocyanine green (ICG). However, ICG is prone to degradation and aggregation under physiological conditions, affecting its photothermal conversion efficiency and in vivo stability. Furthermore, most existing systems are simply co-loaded or physically mixed drugs, lacking rational synergistic design, making it difficult to maximize therapeutic effects.
[0004] To overcome the aforementioned problems, researchers have increasingly turned their attention to metal-organic frameworks (MOFs) as drug delivery carriers. ZIF-8, a typical MOF material, possesses high specific surface area, good biocompatibility, and acid-responsive properties, enabling specific drug release into tumor tissues and making it a promising candidate for multifunctional drug carriers. However, current systems utilizing ZIF-8 for multi-drug synergistic delivery and integrating chemotherapy and photothermal therapy are still relatively limited, particularly in terms of balancing drug stability, delivery efficiency, and therapeutic synergy, where significant room for improvement remains.
[0005] To this end, a ZIF-8 composite material loaded with sulfasalazine (SSZ) and ICG is proposed. Summary of the Invention
[0006] To address the shortcomings of existing technologies, the present invention aims to provide ZIF-8 composite materials loaded with SSZ and ICG, their preparation methods, and applications, thereby solving the problems in the prior art.
[0007] The objective of this invention can be achieved through the following technical solutions:
[0008] A method for preparing ZIF-8 composite materials loaded with SSZ and ICG includes the following steps:
[0009] Sulfasalazine and indocyanine green were mixed with zinc nitrate hexahydrate to obtain a mixture.
[0010] 2-Methylimidazole was added to the mixture and stirred to generate ZIF-8 nanoparticles loaded with sulfasalazine and indocyanine green;
[0011] Unbound impurities in ZIF-8 nanoparticles were removed by centrifugation and washing, and finally dried to obtain ZIF-8 composite material loaded with SSZ and ICG.
[0012] Furthermore, the process of mixing sulfasalazine and indocyanine green with zinc nitrate hexahydrate includes: dissolving zinc nitrate hexahydrate in an organic solvent, then adding sulfasalazine and indocyanine green, and stirring to obtain a mixture.
[0013] Furthermore, the process of generating ZIF-8 nanoparticles loaded with sulfasalazine and indocyanine green includes: dissolving 2-methylimidazole in an organic solvent to obtain a 2-methylimidazole solution; then adding the 2-methylimidazole solution to the mixture and stirring to obtain ZIF-8 nanoparticles.
[0014] Furthermore, the centrifugation and washing process includes: centrifuging the reaction mixture to remove the supernatant, and then washing the precipitate multiple times with an organic solvent to remove unbound impurities and excess 2-methylimidazole.
[0015] Further, the organic solvent is characterized in that it is one or a combination of methanol, ethanol, N,N-dimethylformamide and dimethyl sulfoxide.
[0016] ZIF-8 composite material loaded with SSZ and ICG was prepared using the above-described preparation method.
[0017] The above-mentioned ZIF-8 composite material loaded with SSZ and ICG is used in the preparation of tumor therapeutic drugs.
[0018] Furthermore, the tumor is breast cancer.
[0019] Furthermore, the tumor treatment includes radiotherapy and chemotherapy.
[0020] A tumor treatment drug comprising the aforementioned ZIF-8 composite material loaded with SSZ and ICG.
[0021] The beneficial effects of this invention are:
[0022] 1. This invention is the first to propose that indocyanine green and sulfasalazine be simultaneously encapsulated in the ZIF-8 synthesis process by co-dissolution method. Compared with the traditional "post-loading" or "multi-step encapsulation" strategies, this method greatly simplifies the process and improves drug loading efficiency and structural stability.
[0023] 2. In the composite material of this invention, indocyanine green (ICG) and sulfasalazine (SSZ) are released simultaneously. The former is used for near-infrared responsive photothermal therapy, while the latter acts as a small-molecule chemotherapeutic drug to synergistically enhance cytotoxicity. Compared with single photothermal therapy or single chemotherapy, the synergistic system constructed in this invention exhibits superior antitumor effects, showing significant synergistic cytotoxicity in breast cancer cells. Further analysis shows that the ICG and SSZ synergistic release system described in this invention exhibits significantly enhanced cytotoxicity in breast cancer cells, which is significantly better than SSZ alone, suggesting a possible synergistic mechanism between the two when used together.
[0024] 3. The present invention uses ZIF-8 as a carrier, which has good acid environment response characteristics. It can disintegrate and release drugs in the tumor microenvironment. At the same time, its porous structure has a strong stabilizing effect on indocyanine green molecules, effectively reducing their degradation under light irradiation and improving the efficiency of photothermal therapy.
[0025] 4. The process used in this invention does not require complex modification steps or special reaction conditions, and the material can be synthesized at room temperature and pressure, which has good potential for scale-up production and clinical translation prospects. Attached Figure Description
[0026] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0027] Figure 1 These are schematic diagrams illustrating the characterization of ZIF-8 composite material loaded with SSZ and ICG (SIZ) and ZIF-8 composite material loaded with SSZ (SZ).
[0028] Figure 2 This is a schematic diagram of the photothermal effect of SIZ in this invention;
[0029] Figure 3 This is a graph showing the toxicity test results of ZIF-8, SZ, SIZ and laser irradiation on mouse breast cancer cells. Detailed Implementation
[0030] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0031] Example 1
[0032] This embodiment introduces the ZIF-8 composite material (SIZ) loaded with SSZ and ICG and its preparation process;
[0033] SIZ composite materials include the following components:
[0034] Sulfasalazine (SSZ): As a chemotherapy drug, SSZ has the effect of inhibiting the growth and proliferation of tumor cells; it exerts its anti-tumor effect by interfering with the metabolic process of tumor cells and inducing apoptosis.
[0035] Indocyanine green (ICG): As a photothermal agent, ICG can convert light energy into heat energy under near-infrared light irradiation, producing a photothermal effect. This photothermal effect can directly kill tumor cells, achieving a synergistic effect between photothermal therapy and chemotherapy.
[0036] ZIF-8: As a drug carrier, it loads the two components mentioned above and releases the drug components in response to the tumor microenvironment.
[0037] The preparation process of SIZ composite materials includes:
[0038] S1, sulfasalazine and indocyanine green are mixed with zinc nitrate hexahydrate to obtain a mixed solution;
[0039] Specifically: Under laboratory conditions, 200 mg of zinc nitrate hexahydrate was weighed using a precise electronic balance. The compound was transferred to a 50 mL centrifuge tube, and 5 mL of methanol was added to dissolve the zinc nitrate hexahydrate. After complete dissolution, 5 mg of indocyanine green (ICG) and 5 mg of sulfasalazine (SSZ) were added. The mixture was stirred with a magnetic stirrer at 200 rpm for 30 minutes at room temperature (25°C) to ensure thorough mixing of all components and the formation of a homogeneous mixture.
[0040] S2, 2-methylimidazole is added to the above mixture and stirred to generate ZIF-8 nanoparticles loaded with sulfasalazine and indocyanine green;
[0041] Specifically: Weigh 2.0 g of 2-methylimidazole into another 10 mL centrifuge tube and dissolve it in 10 mL of methanol. Slowly add this 2-methylimidazole solution to the mixture prepared in the first step. Continue stirring the mixture at 200 rpm using a magnetic stirrer at room temperature (25 °C) for an additional 30 minutes to promote the formation of ZIF-8 nanoparticles, during which sulfasalazine and indocyanine green are effectively loaded into the ZIF-8 nanoparticles.
[0042] S3, unbound impurities in ZIF-8 nanoparticles are removed by centrifugation and washing, and then dried to obtain SIZ composite material;
[0043] Specifically, after the reaction was completed, the reaction mixture was centrifuged using a high-speed centrifuge at 10,000 rpm for 10 minutes to collect ZIF-8 nanoparticles loaded with sulfasalazine and indocyanine green. The supernatant was discarded after centrifugation, and the precipitate was washed with methanol, repeating the washing process three times to remove unbound impurities and excess 2-methylimidazole. Finally, the washed nanoparticles were dried in a vacuum drying oven at 40°C to obtain the final SIZ composite material.
[0044] Example 2
[0045] The preparation process of ZIF-8 composite material (SZ) loaded with SSZ specifically includes the following steps:
[0046] This embodiment introduces the ZIF-8 composite material (SZ) loaded with SSZ and its preparation process;
[0047] SZ composite material includes the following components:
[0048] Sulfasalazine (SSZ): As a chemotherapy drug, SSZ has the effect of inhibiting the growth and proliferation of tumor cells; it exerts its anti-tumor effect by interfering with the metabolic process of tumor cells and inducing apoptosis.
[0049] ZIF-8: As a drug carrier, it loads the two components mentioned above and releases the drug components in response to the tumor microenvironment.
[0050] The preparation process of SZ composite material includes:
[0051] S1, sulfasalazine and zinc nitrate hexahydrate are mixed to obtain a mixture;
[0052] Specifically: Under laboratory conditions, 200 mg of zinc nitrate hexahydrate (Zn(NO3)2·6H2O) was weighed using a precise electronic balance. The compound was transferred to a 50 mL centrifuge tube, and 5 mL of methanol was added to dissolve the zinc nitrate hexahydrate. After complete dissolution, 5 mg of SSZ was added. The mixture was stirred with a magnetic stirrer at 200 rpm for 30 minutes at room temperature (25°C) to ensure thorough mixing of all components and the formation of a homogeneous mixture.
[0053] S2, 2-methylimidazole is added to the above mixture and stirred to generate ZIF-8 nanoparticles loaded with sulfasalazine;
[0054] Specifically: Weigh 2.0 g of 2-methylimidazole into another 10 mL centrifuge tube and dissolve it in 10 mL of methanol. Slowly add this 2-methylimidazole solution to the mixture prepared in the first step. Continue stirring the mixture at 200 rpm using a magnetic stirrer at room temperature (25 °C) for an additional 30 minutes to promote the formation of ZIF-8 nanoparticles, during which sulfasalazine is effectively loaded into the ZIF-8 nanoparticles.
[0055] S3, unbound impurities in ZIF-8 nanoparticles were removed by centrifugation and washing to obtain SZ composite material;
[0056] Specifically, after the reaction was completed, the reaction mixture was centrifuged using a high-speed centrifuge at 10,000 r / min for 10 minutes to collect the ZIF-8 nanoparticles loaded with sulfasalazine. The supernatant was discarded after centrifugation, and the precipitate was washed with methanol, repeating the washing process three times to remove unbound impurities and excess 2-methylimidazole. Finally, the washed nanoparticles were dried in a vacuum drying oven at 40°C to obtain the final SZ composite material.
[0057] Example 3
[0058] In this embodiment, SIZ and SZ are characterized by testing.
[0059] Figure 1 A in the image is a scanning electron microscope image of SIZ (scale bar length is 100nm). It can be seen that SIZ particles have a uniform morphology and are relatively dispersed. The statistical particle size is 130nm. This size helps to prolong the in vivo circulation time and avoid rapid clearance by the mononuclear phagocyte system. At the same time, it utilizes the enhanced penetration and retention effect of tumor tissue (EPR effect) to achieve efficient targeted drug delivery, improve drug efficacy and reduce side effects.
[0060] Figure 1B and C in the figure are the ultraviolet spectra of SZ and SIZ, respectively. It can be seen that SIZ has characteristic peaks at 380 nm and 784 nm. The 380 nm peak is the ultraviolet characteristic peak of sulfasalazine, while the 784 nm peak is the ultraviolet characteristic peak of indocyanine green. This proves that both drugs were successfully loaded.
[0061] Example 4
[0062] In this embodiment, the photothermal effect of SIZ was tested, and the test results are as follows: Figure 2 As shown;
[0063] in, Figure 2 In the middle, A represents SIZ at 2W / cm 2 Thermal imaging of temperature changes under 808nm laser irradiation; showing the temperature changes at 808nm and 2W / cm². 2 Under laser irradiation, the material's temperature was recorded every 2 minutes starting from 1 minute, continuing for 5 minutes. This clearly shows the dynamic changes in the material's temperature over time, as well as the accumulation and distribution of heat. It can be seen that the material at 808nm and 2W / cm²... 2 The temperature rises rapidly under laser irradiation, with a significant increase within 1 minute, followed by a continuous increase every 2 minutes, reaching stability after 5 minutes. This indicates that the material has a highly efficient photothermal conversion capability, capable of accumulating and maintaining a high temperature in a short time, providing a stable thermal effect for photothermal therapy. At the same time, the heat distribution is uniform, which is conducive to achieving precise and effective tumor treatment.
[0064] Figure 2 B in the figure represents SIZ at 2W / cm 2 The heating-cooling curve under 808nm laser irradiation reflects the temperature change of 2000mg / L SIZ during the 5-minute heating and 15-minute cooling process. The material temperature rises rapidly to 54.4 degrees Celsius during the heating stage and gradually decreases during the cooling stage, demonstrating the material's good photothermal conversion ability and thermal stability.
[0065] Figure 2 In this context, C represents different concentrations of SIZ at 2W / cm². 2 The heating curves under 808nm laser irradiation show that the temperature of the material tends to stabilize after 5 minutes of irradiation at different concentrations of 500, 1000, 2000, 3000, and 4000 mg / L. The higher the concentration, the higher the final temperature, indicating that the photothermal conversion efficiency of the material increases with increasing concentration. It can also quickly reach a stable temperature output at all concentrations, demonstrating excellent photothermal performance.
[0066] Example 5
[0067] In this embodiment, SIZ cytotoxicity experiments were conducted on 4T1 cells;
[0068] The experimental procedure included: after 24 hours of culture, the 4T1 cell culture medium was aspirated, and different concentrations of Z, SZ, and SIZ suspensions (0, 10, 20, 30, 40, and 50 mg / L) were resuspended in 1640 medium, with 6 replicates per group. A negative control group was also included, consisting of 1640 complete medium without any materials. The cells were cultured for another 24 hours. After culture, the culture medium was aspirated, and 100 μL of medium containing 10% CCK-8 was added. The cells were incubated at 37°C for 1 hour. The absorbance was measured at 480 nm using a microplate reader. Cell viability was calculated and plotted based on the obtained values.
[0069] Experimental results are as follows Figure 3 As shown, compared to ZIF-8 alone, SIZ achieves effective release of SSZ drug within cells. This process significantly enhances cytotoxicity and produces a marked inhibitory effect on tumor cell growth and proliferation. Furthermore, under precise irradiation with an 808nm laser, the photothermal effect of ICG further enhances its killing power against tumor cells, leading to the death of a large number of tumor cells. This fully validates the potential and advantages of SIZ in tumor treatment at the cellular level.
[0070] By comparing the in vitro chemotherapeutic effects of SIZ and SZ at concentrations ranging from 20 to 40 mg / L, the results showed that SIZ exhibited significantly higher cytotoxicity than SZ, suggesting a potential advantage of SIZ in terms of chemotherapeutic activity. This advantage may be related to the synergistic effect between ICG and SSZ in SIZ. In this embodiment, the introduction of ICG was observed to enhance the antitumor activity of SSZ, demonstrating a superior combined effect compared to the single components. Although the specific mechanism is not yet clear, this synergistic effect may involve changes in cell membrane permeability, intracellular environment, or other cellular response pathways.
[0071] Furthermore, under near-infrared laser irradiation, ICG can generate a photothermal effect, and the localized heating may temporarily increase cell membrane permeability, thereby promoting the uptake and accumulation of SSZ by cells. Additionally, heat stress may enhance cellular sensitivity to chemotherapeutic drugs or activate certain stress-related cell death pathways, thus amplifying the cytotoxic response of SSZ to some extent. On the other hand, SSZ itself may possess certain inflammatory regulatory and immune-related activities, and in specific tumor environments, it may interact with photothermal-induced stress responses.
[0072] In the description of this specification, references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.
[0073] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed invention.
Claims
1. A method for preparing ZIF-8 composite material loaded with SSZ and ICG, characterized in that, Includes the following steps: Sulfasalazine and indocyanine green were mixed with zinc nitrate hexahydrate to obtain a mixture. 2-Methylimidazole was added to the mixture and stirred to generate ZIF-8 nanoparticles loaded with sulfasalazine and indocyanine green; Unbound impurities in ZIF-8 nanoparticles were removed by centrifugation and washing, and finally dried to obtain ZIF-8 composite material loaded with SSZ and ICG.
2. The method for preparing ZIF-8 composite material loaded with SSZ and ICG according to claim 1, characterized in that, The process of mixing sulfasalazine and indocyanine green with zinc nitrate hexahydrate includes: dissolving zinc nitrate hexahydrate in an organic solvent, then adding sulfasalazine and indocyanine green, and stirring to obtain a mixture.
3. The method for preparing ZIF-8 composite material loaded with SSZ and ICG according to claim 1, characterized in that, The process for generating ZIF-8 nanoparticles loaded with sulfasalazine and indocyanine green includes: dissolving 2-methylimidazole in an organic solvent to obtain a 2-methylimidazole solution; then adding the 2-methylimidazole solution to the mixture and stirring to obtain ZIF-8 nanoparticles.
4. The method for preparing ZIF-8 composite material loaded with SSZ and ICG according to claim 1, characterized in that, The centrifugation and washing process includes: centrifuging the reaction mixture to remove the supernatant, and then washing the precipitate multiple times with an organic solvent to remove unbound impurities and excess 2-methylimidazole.
5. The method for preparing the ZIF-8 composite material loaded with SSZ and ICG according to any one of claims 2-4, characterized in that, The organic solvent is one or a combination of methanol, ethanol, N,N-dimethylformamide and dimethyl sulfoxide.
6. A ZIF-8 composite material loaded with SSZ and ICG, characterized in that, It was prepared using the preparation method described in any one of claims 1-5.
7. The use of the ZIF-8 composite material loaded with SSZ and ICG as described in claim 6 in the preparation of tumor therapeutic drugs.
8. The application according to claim 7, characterized in that, The tumor is breast cancer.
9. The application according to claim 7, characterized in that, The tumor treatments include radiotherapy and chemotherapy.
10. A tumor treatment drug, characterized in that, The ZIF-8 composite material containing SSZ and ICG as described in claim 6.