Tumor microenvironment response type precise delivery nano-carrier as well as preparation method and application thereof

Abstract

The invention discloses a tumor microenvironment response type precise delivery nano-carrier as well as a preparation method and application thereof, and belongs to the technical field of nano-materials. Aiming at the problem of poor technical effect of an existing drug delivery system, the tumor microenvironment response type precise delivery nano-carrier is characterized in that a metal organic framework is wrapped by hyaluronic acid HA and human serum albumin HSA; the metal organic framework is an iron-based metal organic framework; a chemotherapeutic drug adriamycin is loaded in the metal organic framework; and a radionuclide 131I is marked on the surface. The metal organic framework is spherical and contains iron, carbon and oxygen, Fe < 2 + > / Fe < 3 + > pairs exist, and the loading ratio of Fe < 3 + > is 2.38 w%. Iron ions generated by cracking of the metal organic framework are used as a nuclear magnetic contrast agent; the hyaluronic acid is used for targeting tumor surface CD44 protein. In-vitro and in-vivo experiments prove that the nano-material has good biological safety, nuclide labeling stability and MRI and SPECT imaging capability, positions tumor parts in real time, monitors tumor forms and sizes, and remarkably inhibits tumor growth.

Description

Technical Field

[0001] The present invention belongs to the technical field of nanomaterials, and specifically relates to a nanocarrier for tumor microenvironment-responsive precise delivery, a preparation method, and an application thereof. Background Art

[0002] Radionuclide-based combined chemotherapy and radiotherapy have been widely used in clinical enhanced cancer treatment. However, systemic administration of radionuclides and anticancer drugs usually leads to rapid metabolism and non-specific distribution, which can cause significant toxic effects on patients. Improving the efficiency of radionuclide delivery, increasing the sensitivity of obtaining lesion information, and enhancing the efficacy of tumor treatment based on nanomedicine strategies have become research hotspots. Nanocarriers can carry a variety of drugs or imaging agents due to their unique physical, chemical, and biological properties to construct nanocarriers that integrate diagnosis and treatment. Carriers can achieve spatiotemporal controlled drug release and targeted therapy under the guidance of imaging, thereby increasing the local concentration of drugs and implementing treatment accurately. Therefore, radionuclide-labeled nanocarriers provide an effective way to overcome difficulties in the field of cancer diagnosis and treatment.

[0003] Metal-organic frameworks (MOFs), as a new type of self-assembled porous material with metal connection points and organic bridging ligands, have been widely studied and applied in various potential biomedical fields. Among them, iron-based MOFs (MIL-100(Fe)) have attracted attention due to their high porosity, large surface area, biocompatibility and biodegradability. They can be used as carriers for drug delivery and as T2 contrast agents for magnetic resonance imaging.

[0004] Although drug-loaded metal-organic frameworks have made certain research progress, they still have limitations in tumor treatment: (1) The drug loading capacity and encapsulation rate of metal-organic frameworks are not high, which can easily lead to drug leakage before reaching the administration site, resulting in poor efficacy; the drug lacks active targeting, and there are limitations in improving its accumulation at the tumor site; (3) The chemotherapy efficacy of metal-organic frameworks labeled with radionuclides sometimes weakens over time and may cause tumor cells to become radioresistant. Summary of the invention

[0005] In view of the problem that the existing drug delivery system has poor technical effects, the present invention provides a drug delivery carrier with tumor microenvironment response and MRI / SPECT dual-modality imaging real-time monitoring functions.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] A nanocarrier for tumor microenvironment-responsive precise delivery, wherein the nanocarrier is a metal organic framework wrapped with hyaluronic acid HA and human serum albumin HSA; the metal organic framework is an iron-based metal organic framework MIL-100 (Fe); the chemotherapy drug doxorubicin DOX is loaded in the metal organic framework; and a radioactive nuclide is labeled on its surface 131 I.

[0008] Furthermore, the metal organic framework is spherical and contains three elements: iron, carbon and oxygen. 2+ / Fe 3+ Yes, Fe 3+ The load ratio is 2.38w%.

[0009] Furthermore, the iron ions generated by the decomposition of the metal organic framework are used as nuclear magnetic resonance contrast agents; and the hyaluronic acid is used to target CD44 protein on the surface of tumors.

[0010] A method for preparing a tumor microenvironment responsive precision delivery nanocarrier comprises the following steps:

[0011] Step 1, Synthesis of the iron-based metal organic framework MIL-100(Fe):

[0012] FeCl3·6H2O and 1,3,5-benzenetricarboxylic acid BTC were dissolved in methanol, mixed and vigorously stirred at room temperature to obtain a mixture, and then the mixture was subjected to oil bath reaction, centrifuged and washed to obtain the iron-based metal organic framework MIL-100(Fe);

[0013] Step 2, preparation of MHH nanomaterials:

[0014] MIL-100(Fe), hyaluronic acid HA, and human albumin HSA are mixed and stirred in an aqueous solution to coat a layer of hyaluronic acid HA / human albumin HSA mixture on the surface of MIL-100(Fe) to obtain MHH nanomaterials;

[0015] Step 3, preparation of MHHD nanomaterials:

[0016] The doxorubicin DOX and MHH nanomaterials were stirred in an aqueous solution in the dark, and then centrifuged to remove the unloaded free DOX molecules to obtain MHHD nanomaterials;

[0017] Step 4, preparation of 131I-MHHD nanocarriers:

[0018] Will Na 131 I. MHHD and chloramine T solution were stirred and mixed at room temperature, and the unlabeled 131 I, get 131 I-MHHD nanocarrier.

[0019] Furthermore, the mass ratio of MIL-100(Fe), HA and HSA is 10:1:1 or 5:1:1.

[0020] Furthermore, the mass ratio of doxorubicin DOX to MHH nanomaterial is 1:1.

[0021] Furthermore, the Na 131 I. The reaction ratio of MHHD and chloramine T solution is 1mCi:1mg:2mg.

[0022] The temperature of the oil bath reaction in step 1 is 70° C. and the reaction time is 90 min;

[0023] The centrifugal speed in step 1 is 12000 rpm.

[0024] In step 1, washing is performed with ethanol and deionized water for 3 times each;

[0025] The pH of the aqueous solution in step 2 is 8.0, and the stirring time is 24 hours.

[0026] Application of nanocarriers for tumor microenvironment-responsive precision delivery as co-delivery vehicles for radionuclides and anticancer drugs.

[0027] Application of tumor microenvironment-responsive precision delivery nanocarriers as tumor-targeted delivery vehicles.

[0028] Application of tumor microenvironment-responsive precision delivery nanocarriers in the preparation of tumor therapeutic drugs.

[0029] HA can specifically bind to the CD44 protein highly expressed on the tumor surface to achieve the targeted tumor site of the vector. 131 I can emit β rays to produce ionizing radiation to kill tumor cells. At the same time, the carrier can activate and release DOX in the tumor microenvironment to inhibit DNA synthesis and increase the sensitivity of tumor cells to radiation, thereby achieving radionuclide therapy (RNT) combined with chemotherapy to treat tumors.

[0030] Compared with the prior art, the present invention has the following advantages:

[0031] 1. The present invention utilizes a nanoprobe carrier metal organic framework to significantly improve the encapsulation rate and drug loading rate of drugs, and synchronously releases chemotherapeutic drugs in response to the acidic microenvironment in tumor cells, exerting a synergistic anti-tumor effect, thereby improving the tumor treatment effect.

[0032] 2. The tumor microenvironment responsive nanoprobes provided by the present invention can be loaded with radiotherapy and chemotherapy drugs, accurately targeted to the tumor site, and achieve coordinated treatment of radiotherapy and chemotherapy.

[0033] 3. The present invention confirms through in vitro cell and animal experiments that the MHHD has good targeted anti-tumor ability, significantly inhibits the survival rate of CD44-positive expressing cells, and significantly inhibits the growth of mouse tumors.

[0034] 4. The in vitro and in vivo experiments of the present invention confirm that the nanoprobe has good biosafety, radionuclide labeling stability, MRI (nuclear magnetic resonance imaging) and SPECT (single photon emission computed tomography) imaging capabilities, and can not only locate the tumor site and monitor the tumor morphology and size in real time, but also significantly inhibit tumor growth. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 This is the TEM image of MIL-100(Fe).

[0036] Figure 2 This is the XPS full spectrum of MIL-100(Fe) and the detailed spectrum of iron element.

[0037] Figure 3 This is the TEM image of MHHD.

[0038] Figure 4 is the Zeta potential of MIL-100(Fe), MHH, and MHHD.

[0039] Figure 5 TEM images of untreated MHHD (a), and TEM images of MHHD placed in PBS solutions at pH 7.4 (b) and pH 5.5 (c) for 24 h.

[0040] Figure 6 is the particle size distribution of MIL-100(Fe) and MHHD.

[0041] Figure 7 UV-visible absorption spectra of MIL-100(Fe) and MHHD.

[0042] Figure 8 is the drug loading rate and encapsulation efficiency of DOX in MH and MHH.

[0043] Fig. 9 is the cumulative release rate of DOX from MHHD under different conditions.

[0044] Fig.10 is the relaxation rate R2(1 / T2) and the relationship between different Fe 3+ Relationship of MHHD concentrations.

[0045] Fig.11 CLSM images of MHHD after incubation with 3T3 or 4T1 cells at pH 7.4 / 5.5.

[0046] Fig.12 The cell survival rate was measured when 4T1 / 3T3 cells were incubated with different concentrations of MHH for 24 h at pH 7.4.

[0047] Fig.13 Cell viability of 4T1 cells co-incubated with vectors at different concentrations for 24 h at pH 7.4.

[0048] Fig.14 This is the immunofluorescence imaging of γ-H2AX in 4T1 cells after being treated with different vectors under different conditions of pH 7.4 and pH 5.5.

[0049] Fig.15 The figures are the tumor volumes of tumor-bearing mice after different treatments.

[0050] Fig.16 Tumor-bearing mice were injected via tail vein 131 T2-weighted MR images of I-MHHD at different time points.

[0051] Fig.17 This is the SPECT imaging of 4T1 tumor-bearing mice after different treatments of the tail vein.

[0052] Fig.18 These are H&E stained sections of various organs. DETAILED DESCRIPTION

[0053] In order to gain a deeper understanding of the present invention, we will provide a comprehensive and detailed description of the present invention. However, the present invention has multiple implementations and is not limited to the specific examples listed herein. The presentation of these examples is intended to deepen the comprehensive understanding of the disclosure of the present invention.

[0054] 1. Materials:

[0055] 1,3,5-Benzenetricarboxylic acid (BTC), iron (III) chloride hexahydrate (FeCl3·6H2O), doxorubicin hydrochloride, hyaluronic acid, and chloramine T trihydrate were purchased from Shanghai Aladdin Biochemical Technology Co., Ltd.

[0056] Methanol and anhydrous ethanol were purchased from Tianjin Fangdatongzheng Chemical Co., Ltd.

[0057] Na131I was provided by the Department of Nuclear Medicine, the First Affiliated Hospital of Shanxi Medical University.

[0058] DMEM culture medium, fetal bovine serum, penicillin-streptomycin solution and trypsin were purchased from Gibco.

[0059] All reagents used in the experiments were of analytical grade and were used directly without further treatment.

[0060] 4T1 breast cancer cells were purchased from Wuhan Pronocell Life Science Co., Ltd.

[0061] Balb / c mice (female, 4 weeks) were purchased from Sibeifu Biotechnology Co., Ltd. (Beijing).

[0062] 2. Characterization

[0063] The morphologies of MII-100(Fe) and MHHD were observed by HT7700 transmission electron microscope (Hitachi, Japan).

[0064] The particle size and potential of MIL-100(Fe) and MHHD were measured by Zetasizer Labblue (Malvern, UK).

[0065] The UV-visible absorption spectra were measured using a UH 5700 UV-Vis spectrophotometer (Hitachi, Japan).

[0066] Elemental analysis of MII-100(Fe) was performed by X-ray photoelectron spectroscopy (XPS).

[0067] The T2-weighted images of MHHD were measured by a 7.0T Micro-MR imager (Bruker, Germany).

[0068] Example 1 Preparation method of tumor microenvironment responsive precision delivery nanocarrier

[0069] Synthesis of MII-100(Fe)

[0070] First, 7.5 mM FeCl3·6H2O and 7.5 mM BTC were dissolved in 40 mL methanol, mixed and stirred vigorously at room temperature for 10 min. Then, the mixture was transferred to a 70°C oil bath for 90 min, and the reaction product was collected by centrifugation at 12,000 rpm and washed three times with ethanol and deionized water. Finally, the product was freeze-dried and stored at 4°C for use.

[0071] Synthesis of MHH, MHD and MHHD Nanomaterials

[0072] MIL-100(Fe):HSA at a mass ratio of 5:1 or MIL-100(Fe):HA:HSA at a mass ratio of 10:1:1 was mixed and stirred in an aqueous solution for 24 hours to promote the conjugation of MIL-100(Fe) with HSA or with HA and HSA at the same time to generate MIL-100(Fe)@HSA(MH) or MIL-100(Fe)@HA-HSA(MHH); then DOX was mixed with MIL-100(Fe)@HSA or MIL-100(Fe)@HA-HSA at a mass ratio of 1:1 and put into an aqueous solution, and then stirred in the dark for 12 hours, and the unloaded free DOX molecules were removed by centrifugation to obtain MIL-100(Fe)@HSA@DOX(MHD) or MIL-100(Fe)@HA-HSA@DOX(MHHD).

[0073] Figure 1 This is the TEM image of MIL-100(Fe), which shows that MIL 100(Fe) has a complete morphology, relatively uniform size, and good dispersion.

[0074] Figure 2 The X-ray photoelectron spectroscopy (XPS) full spectrum analysis of MIL-100(Fe) shows that the MIL-100(Fe) sample has Fe2p, C1s, and O1s absorption peaks, indicating that the sample mainly contains three elements: iron, carbon, and oxygen. The high-resolution spectrum of the iron element shows that the sample contains Fe 2+ / Fe 3+ Yes, Fe 3+ The loading ratio of is about 2.38% (w / w%).

[0075] Figure 3 This is the TEM image of MHHD, which shows that the morphology of MHHD has not changed significantly compared with MIL-100(Fe).

[0076] Figure 4 Zeta potential Due to the negatively charged carboxyl groups of HA, its surface potential decreased from -8.60±0.56 mV to -30.08±0.58 mV. After loading with positively charged DOX, the zeta potential further increased to -16.66±0.57 mV, indicating that HA / HSA was successfully encapsulated on the surface of MIL-100(Fe) and loaded with DOX.

[0077] Figure 5We further tested whether MHHD had acidic response characteristics. TEM results confirmed that MIL-100(Fe) was significantly degraded after being placed at pH 5.5 for 24 h, and the particle shape became irregular, while only partial degradation occurred at pH 7.4, indicating that MHHD may be an acid-sensitive metal-organic framework that is conducive to degradation and drug release in the acidic microenvironment of the tumor.

[0078] Figure 6 Comparing the surface potential and particle size changes of MIL-100(Fe) before and after encapsulating the HA / HSA mixture, it can be seen that the average hydrated particle size of MIL-100(Fe) is 146.1±12.50nm, which increases to 169.9±15.28nm after encapsulating HA / HSA.

[0079] Figure 7 The results of UV-visible absorption spectrum showed that MIL-100(Fe) and DOX had characteristic absorption peaks at 213nm and 480nm, respectively. The characteristic peak of MIL-100(Fe) existed in the MHHD absorption spectrum, while the absorption peak of DOX red-shifted from 480nm to 490nm, which was due to the loading of DOX in the outer layer HSA of the carrier, further confirming the successful loading of doxorubicin.

[0080] Example 2 Calculation of drug loading rate and encapsulation efficiency

[0081] The drug loading rate and encapsulation rate of DOX were determined by UV-visible spectrophotometer analysis. First, doxorubicin was loaded into MH or MHH at a mass ratio of 1:1 to form MHD and MHHD, respectively. Then, the product was washed with ultrapure water and centrifuged (12000rpm, 10min) to remove unloaded free DOX until the supernatant was clear, and the washed supernatant was collected and the absorbance at a wavelength of 480nm was measured by UV-visible spectrophotometer. The drug loading rate and encapsulation rate of DOX were calculated according to the standard curve of doxorubicin. Drug loading rate: LE (%) = (total amount of drug administered - unloaded amount) / (total amount of drug administered) × 100%; Encapsulation rate: ER (%) = (total amount of drug administered - unloaded amount) / (total amount of input) × 100%.

[0082] Figure 8 The drug loading rate of MHHD reached 93.28±5.45%, and the encapsulation rate reached 44.01±1.49%, which had no significant difference with those of MHD NPs, indicating that the addition of HA targeting molecules had no effect on its drug loading capacity.

[0083] Example 3 Detection of the release rate of doxorubicin in MHHD

[0084] To detect the release rate of MIL-100@HA-HSA@DOX at different pH, 2 mL of MHHD (DOX concentration of 0.4 mg / mL) solution was taken into a dialysis bag (MWCO3500). The dialysis bag was then placed in PBS solutions (10 mL) with different pH values ​​of 7.4, 5.5 and pH = 5.5 + 2 or 10 mM GSH, and the absorbance of DOX at 480 nm in PBS solution was measured at different time periods (0, 1, 2, 4, 6, 10, 24, 48, 72 h) and the percentage of DOX release was calculated.

[0085] Fig. 9 Under the same pH conditions, the DOX release rate in the solution containing GSH was significantly improved, and the DOX release rate increased with the increase of GSH concentration. At pH = 5.5 and 10 mmol GSH, the cumulative release rate of DOX in 72 h was as high as 69.93±8.02%, proving that MHHD can achieve drug controlled release with the help of tumor microenvironment.

[0086] Example 4 Detection of the Nuclear Magnetic Effect of MHHD

[0087] In order to verify the nuclear magnetic effect of iron ions in MHHD, 3+ Concentration (CFe 3+ =0, 0.1, 0.2, 0.4, 0.8 mM) conditions, and the relaxation rate R2 (1 / T2) was calculated based on the relaxation time (T2).

[0088] Fig.10 The T2-weighted images of MHHD nanoprobes were detected, and darker MR images were obtained with the increase of MHHD concentration in the solution. The transverse relaxation rate (R2) of MHHD NPs was about 96.88mM-1s-1, which has the potential to be a new contrast agent.

[0089] Example 5 In vitro cellular uptake

[0090] To further demonstrate the targeting and phagocytic level of the drug, 3T3 and 4T1 cells were inoculated into laser confocal culture dishes, cultured overnight in an incubator, and MHHD (DOX = 2 μg) was added to the culture dishes at different time points on the second day. Then, the supernatant was adsorbed and washed 3 times with PBS. The cell nuclei were stained with 100 μL DAPI for 10 minutes and then washed 3 times. Finally, the uptake of doxorubicin in the cells was observed using a laser confocal microscope imager.

[0091] Fig.11Only a weak DOX fluorescence signal was observed in 3T3 cells under pH 7.4 conditions, while the DOX fluorescence signal observed in 4T1 cells was significantly higher than that in 3T3. This is because the CD44 protein expression on the surface of 3T3 cells is negative, while it is overexpressed in 4T1 cells.

[0092] Example 6 Cytotoxicity Test

[0093] The cytotoxicity of MHH NPs was determined using 4T1 mouse breast cancer cells. 4T1 cells were seeded in a 96-well plate and incubated for 24 hours, and then incubated for 24 hours with culture medium containing different concentrations of MHHNPs (50, 100, 200, 400, 800 μg / mL). The culture medium was discarded, and 90 μL of DMEM culture medium and 10 μL of CCK8 reagent were added to each well. After 2 hours, the absorbance at a wavelength of 450 nm was measured using an ELISA reader, and the cell survival rate was calculated: Cell survival rate (%) = (OD sample-OD blank) / (OD control-OD blank)*100, where the blank group only had DMEM culture medium and CCK8 reagent, and the control group was cells without any treatment.

[0094] Fig.12 The unloaded probe MHH showed good stability at concentrations up to 800 μg mL -1 When the cell culture medium was used, the survival rates of mouse embryonic fibroblast 3T3 cells and mouse breast cancer 4T1 cells were both higher than 90%, indicating that the material itself has low cytotoxicity and good biosafety.

[0095] Example 8 In vitro treatment

[0096] 3T3 and 4T1 cells were inoculated into 96-well plates and cultured overnight. The culture medium was aspirated and washed with PBS. Then PBS, 131 I. 131 I-MHH, 131 I-MHD、MHHD、 131 I-MHHD( 131 I: 3μCi; DOX: 2μg), then add 100μL of DMEM culture medium to each well, incubate for 4h, wash 3 times with PBS to remove excess probe, add 90μL of DMEM culture medium and 10μL of CCK8 reagent to each well, and detect the absorbance at 450nm with an enzyme reader after 2h to calculate the cell survival rate.

[0097] 4T1 cells were inoculated in 12-well plates and cultured overnight, and then treated with PBS of different pH values ​​(pH = 5.5, 7.4), 131 I.DOX 131 I-MHH, 131 I-MHD, MHHD and 131 I-MHHD (DOX: 10 μg;131 I: 15 μCi) DMEM solution was used to treat the cells. After incubation for 4 h, the cells were treated with γ-H2AX and DAPI and observed under a fluorescence microscope.

[0098] Fig.13 In CCK experiment 131 The cell survival rate of the I-MHHD group was significantly lower than that of the other groups. 131 The I-MHHD group had a higher accumulation of CD44-targeting molecule HA in 4T1 cells, resulting in a stronger therapeutic effect.

[0099] Fig.14 Under neutral conditions, 131 The free group showed only weak green fluorescence and caused only a very small amount of DNA breakage. The killing ability of DOX alone on tumor cells was better than that of the MHHD group loaded with the same concentration of DOX. This is because the amount of DOX released in MHHD under neutral conditions is relatively small. 131 I-MHH is relatively free 131 Group I, 131 I-MHHD compares 131 The green fluorescence of the I-MHD group was strong, proving that the carrier-encapsulated hyaluronic acid had significant targeting effect on 4T1 cells and improved the therapeutic efficacy of the probe.

[0100] Example 9

[0101] When the tumor volume reaches 100 mm 3 The Balb / C tumor-bearing mice were randomly divided into 5 groups and injected with 100 μL of PBS, 131 I (200μCi), DOX, 131 I-MHD, MHHD and 131 I-MHD (DOX = 1 mg / kg, 131 I=200μCi), and the changes of mouse body weight and tumor were recorded every other day.

[0102] Fig.15 During the treatment period, PBS was injected into the tail vein. 131 I, DOX and 131 In the I-MHD group, the tumor tissue continued to grow larger over time. 131 The tumor inhibition rate of I-MHD was significantly lower than 131 In the I-MHHD group, the lack of the targeting protein HA resulted in less accumulation in the tumor site, which reduced its therapeutic effect. The tumor growth in the MHHD group was significantly lower. 131I-MHD, DOX and control group, which may be due to the fact that MHHD can deliver chemotherapy drugs to the tumor site through its surface HA, and release drugs with the help of the acidic and high GSH concentration microenvironment of the tumor site, thereby inhibiting tumor growth. 131 The tumor growth rate in the I-MHHD combined treatment group was significantly lower than that in the MHHD group. This was because the simultaneous combination treatment of radionuclides and chemotherapy drugs significantly improved the inhibitory effect on tumors.

[0103] Example 10

[0104] Each mouse was injected subcutaneously on the right side of the hind leg with 2.0 × 10 6 4T1 cells were used to establish a tumor model (female, Balb / C, 4 weeks). When the tumor volume reached 200 mm 3 4T1 tumor-bearing mice were randomly divided into 3 groups and injected with MHHD (DOX = 1 mg) via the tail vein or intratumorally. In vivo MR imaging was performed at room temperature using a 7.0T Micro MRI at different time points after injection (0, 3, 6, 9, 12, 24 h and 3d, 7d), and the relaxation time (T2) of the mouse tumor site was obtained. T2-weighted MR images were obtained using the following parameters: repetition time (TR) = 2200, echo time (TE) = 8.0 ms, field of view (FOV) = 3.5 × 35 mm, slice thickness = 1 mm, 7 consecutive slices. The relaxation rate R2 = 1 / T2 was calculated based on the relaxation time (T2) of the mouse tumor site.

[0105] Fig.16 Intratumoral injection via tail vein 131 I-MHHD was injected into mice, and MR imaging was performed at different time points. The results showed that after tail vein injection, there was a significant darkening effect at the tumor site of the mice, which was most obvious at 9 hours, and then the darkening effect of the tumor site gradually weakened.

[0106] Embodiment 11

[0107] Each mouse was injected subcutaneously on the right side of the hind leg with 2.0 × 10 6 4T1 cells were used to establish tumor models (female, Balb / C, 4 weeks old). When the tumor volume reached 200 mm 3 The 4T1 tumor-bearing mice were randomly divided into three groups and injected with 100 μL of 131 I(200μCi), 131 I-MHD (200 μCi) or 131 I-MHHD (200 μCi), whole-body images of mice were obtained using ImaginE NET 632 SPECT at different time points (0, 3, 6, 9, 12, and 24 h) after injection.

[0108] Fig.17 131 I is taken up by the thyroid gland in large quantities 3 hours after injection, with a small amount accumulated in organs, and almost all of it is taken up by the thyroid gland by 9 hours. 131 In the I-MHHD group, it can be observed that the signal at the tumor site reached a peak 9 hours after vector injection, and then gradually weakened, with only a very small amount being taken up by the thyroid gland, which is consistent with the results of MRI imaging.

[0109] Example 12

[0110] When the tumor volume reaches 100 mm 3 The Balb / C tumor-bearing mice were randomly divided into 5 groups and injected with 100 μL of PBS, 131 I (200μCi), DOX, 131 I-MHD, MHHD and 131 I-MHD (DOX = 1 mg / kg, 131 I=200μCi), and the changes of mouse body weight and tumor were recorded every other day. 131 The heart, liver, spleen, lung and kidney of the two I-MHHD groups of mice were respectively obtained for H&E staining to observe the histopathological changes of each organ.

[0111] Fig.18 The main organs (heart, liver, spleen, lung and kidney) were collected for H&E staining, and no obvious pathological changes were found in the results, indicating that 131 I-MHHD treatment has no obvious side effects and has good biosafety.

[0112] The contents not described in detail in the specification of the present invention belong to the prior art known to the professional and technical personnel in the field. Although the illustrative specific embodiments of the present invention are described above to facilitate the understanding of the present invention by the technical personnel in the field, it should be clear that the present invention is not limited to the scope of the specific embodiments. For the ordinary technical personnel in the field, as long as various changes are within the spirit and scope of the present invention defined and determined by the attached claims, these changes are obvious, and all inventions and creations using the concept of the present invention are protected.

Claims

1. Tumor microenvironment-responsive precise delivery nanocarrier, characterized by: The nanocarrier is a metal organic framework wrapped with hyaluronic acid HA and human serum albumin HSA; the metal organic framework is an iron-based metal organic framework MIL-100 (Fe); doxorubicin DOX is loaded in the metal organic framework; and radionuclides are labeled on its surface 131 I.

2. The tumor microenvironment responsive precision delivery nanocarrier according to claim 1, characterized in that: The metal organic framework is spherical and contains three elements: iron, carbon and oxygen. 2+ / Fe 3+ Yes, Fe 3+ The load ratio is 2.38w%.

3. The tumor microenvironment responsive precision delivery nanocarrier according to claim 1, characterized in that: The iron ions generated by the decomposition of the metal organic framework are used as nuclear magnetic resonance contrast agents; the hyaluronic acid is used to target CD44 protein on the surface of tumors.

4. The method for preparing a tumor microenvironment responsive precision delivery nanocarrier according to claim 1, characterized in that: The following steps are involved: Step 1, synthesis of the iron-based metal organic framework MIL-100 (Fe): dissolving FeCl3·6H2O and 1,3,5-benzenetricarboxylic acid BTC in methanol, mixing and vigorously stirring at room temperature to obtain a mixture, then subjecting the mixture to an oil bath reaction, centrifuging, and washing to obtain the iron-based metal organic framework MIL-100 (Fe); Step 2, preparation of MHH nanomaterials: MIL-100 (Fe), hyaluronic acid HA, and human serum albumin HSA are mixed and stirred in an aqueous solution to coat a layer of hyaluronic acid HA / human serum albumin HSA mixture on the surface of MIL-100 (Fe) to obtain MHH nanomaterials; Step 3, preparation of MHHD nanomaterials: stirring doxorubicin DOX and MHH nanomaterials in an aqueous solution in the dark, and then centrifuging to remove unloaded free DOX molecules to obtain MHHD nanomaterials; Step 4, 131 Preparation of I-MHHD nanocarriers: Na 131 I. MHHD and chloramine T solution were stirred and mixed at room temperature, and the unlabeled 131 I, get 131 I-MHHD nanocarrier.

5. The method for preparing a tumor microenvironment responsive precise delivery nanocarrier according to claim 4, characterized in that: The mass ratio of the MIL-100(Fe), HA and HSA is 10:1:

1.

6. The method for preparing a tumor microenvironment responsive precise delivery nanocarrier according to claim 4, characterized in that: The mass ratio of doxorubicin DOX to MHH nanomaterial is 1:

1.

7. The method for preparing a tumor microenvironment responsive precise delivery nanocarrier according to claim 4, characterized in that: The Na 131 I, the reaction ratio of MHHD and chloramine T solution is 1mCi:1mg:2mg.

8. The use of the tumor microenvironment responsive precise delivery nanocarrier according to claim 1, characterized in that: As a co-delivery vehicle for radionuclides and anticancer drugs.

9. The use of the tumor microenvironment responsive precise delivery nanocarrier according to claim 1, characterized in that: As a tumor-targeted delivery vehicle.

10. Use of the tumor microenvironment responsive precision delivery nanocarrier according to claim 1 in the preparation of tumor therapeutic drugs.

Images