A marker precursor and probe for bone metastasis and its preparation method and application

Abstract

The present invention relates to the field of imaging technology, and in particular to a marker precursor, a probe, and a preparation method and application thereof for bone metastasis. In the present invention, a marker precursor for bone metastasis is synthesized by modifying alendronic acid with Boc-β-alanine and phenylalanine to adjust its hydrophilicity and lipophilicity, and using DOTA-NHS as a chelating agent. 68 The probe was labeled with Ga and constructed. This probe not only enhances bone affinity, but also reduces radioactive uptake in non-target organs such as kidney and liver, and improves the ratio of bones to major organs such as bone / kidney.

Description

Technical Field

[0001] The invention relates to the field of imaging technology, and in particular to a marker precursor and probe of bone metastasis and a preparation method and application thereof. Background Art

[0002] The information disclosed in this background technology section is only intended to enhance the understanding of the overall background of the invention, and should not necessarily be regarded as an admission or any form of suggestion that the information constitutes the prior art already known to a person skilled in the art.

[0003] The incidence of malignant tumors is increasing year by year, and bones are a common site of late metastasis of malignant tumors. Approximately 65-75% of patients with prostate cancer and breast cancer, 30-40% of patients with lung cancer, and 15-30% of patients with colorectal cancer will develop bone metastases. Bone metastases usually have no symptoms in the early stages, but when related symptoms such as cancerous bone pain, pathological fractures, and hypercalcemia appear, the best time for treatment has been missed and the prognosis is poor. Single photon emission tomography (SPECT) and positron emission tomography (PET) are two commonly used nuclear medicine detection methods in clinical practice. Although SPECT imaging is the standard diagnostic method for nuclear medicine bone imaging, PET imaging has become an important auxiliary examination method for diagnosing bone metastases in recent years due to its advantages such as high sensitivity and quantitative analysis.

[0004] Radioactive tracers used to diagnose bone metastases need to meet the following requirements: (1) excellent affinity for bone; (2) higher selectivity for bone metastases relative to other tissues; (3) high stability in vivo; and (4) long retention time in vivo. However, the radioactive tracers reported so far for bone metastases all have certain limitations and cannot be transformed into clinical practice. Summary of the invention

[0005] In order to overcome the above problems, the present invention provides a marker precursor and probe for bone metastasis and a preparation method and application thereof.

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

[0007] In the first aspect of the present invention, a marker precursor for bone metastasis is provided, the structural formula of which is shown in formula (I):

[0008]

[0009] Formula (I).

[0010] The second aspect of the present invention provides a method for preparing the marker precursor of bone metastasis described in the first aspect, comprising:

[0011] Boc-β-alanine reacts with phenylalanine to obtain intermediate 1;

[0012] Intermediate 1 reacts with alendronic acid to obtain intermediate 2;

[0013] Intermediate 2 reacts with the chelating agent tetraazacyclododecane tetraacetic acid-succinimidyl ester (DOTA-NHS) to obtain a labeled precursor of bone metastasis;

[0014] Wherein, the structural formula of intermediate 1 is shown in formula (II);

[0015]

[0016] Formula (II);

[0017] The structural formula of intermediate 2 is shown in formula (III);

[0018]

[0019] Formula (III).

[0020] The third aspect of the present invention provides a probe comprising the labeled precursor of bone metastasis described in the first aspect and / or the labeled precursor of bone metastasis prepared by the preparation method described in the second aspect and a radionuclide.

[0021] A fourth aspect of the present invention provides a method for preparing the probe according to the third aspect, comprising:

[0022] After the radioactive nuclide is mixed and reacted with the labeling precursor of the bone metastasis, a probe is obtained.

[0023] The fifth aspect of the present invention provides the use of the bone metastasis marker precursor described in the first aspect and / or the bone metastasis marker precursor prepared by the preparation method described in the second aspect and / or the probe of the third aspect and / or the probe prepared by the preparation method described in the fourth aspect in the preparation of products for detecting bone metastasis.

[0024] The sixth aspect of the present invention provides a product for detecting bone metastases, comprising the labeled precursor of bone metastases described in the first aspect and / or the labeled precursor of bone metastases prepared by the preparation method described in the second aspect and / or the probe of the third aspect and / or the probe prepared by the preparation method described in the fourth aspect.

[0025] The beneficial effects of the present invention are:

[0026] (1) In the present invention, alendronic acid is modified with Boc-β-alanine and phenylalanine to adjust its hydrophilicity and lipophilicity, and DOTA-NHS is used as a chelating agent to synthesize a marker precursor for bone metastasis. 68The probe was labeled with Ga and constructed. This probe not only enhances bone affinity, but also reduces radioactive uptake in non-target organs such as kidney and liver, and improves the bone to major organ ratio (TNT) such as bone / kidney (T / K).

[0027] (2) The high radiochemical purity of the probe was verified through in vitro radiochemical property experiments. The good stability of the probe in vitro was verified through in vitro stability studies. The good hydrophilicity of the probe was verified through hydrophilicity and lipophilicity studies. The high affinity of the probe to hydroxyapatite was verified through in vitro hydroxyapatite binding experiments, which laid the foundation for its bone affinity in vivo. Subsequently, the in vivo stability, biosafety and biodistribution experiments were conducted to verify that the probe has good stability, good bone affinity and long residence time in vivo. The tumor imaging effect of the probe was investigated through small animal PET / CT, and it was found that the probe can be used for in vivo imaging of bone metastases, and therefore has good clinical application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The accompanying drawings in the specification, which constitute a part of the present invention, are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0029] Figure 1 The reaction route of the bone metastasis marker precursor represented by formula (I);

[0030] Figure 2 is the ESI-MS mass spectrum of the labeled precursor AABP3;

[0031] Figure 3 is the H NMR spectrum of the labeled precursor AABP3;

[0032] Figure 4 For the synthesis in Example 2 68 Radiochemical purity test diagram of Ga-AABP3;

[0033] Figure 5 for 68 In vitro stability test results of Ga-AABP3, where A is the stability test result of PBS buffer solution and B is the stability test result of serum;

[0034] Figure 6 for 68 In vivo stability test results of Ga-AABP3, where A, B, C and D are the stability test results in blood, urine, kidney and liver, respectively;

[0035] Figure 7 for 68 Blood clearance curve of Ga-AABP3;

[0036] Figure 8for 68 Body weight monitoring curve of mice after Ga-AABP3 injection;

[0037] Fig. 9 for 68 HE staining of important organs of Ga-AABP3 (blank control group); A, B, C, D, E, F, G, H, I and J refer to heart, liver, spleen, lung, kidney, stomach, small intestine, muscle, femur and brain respectively;

[0038] Fig.10 for 68 HE staining of important organs of Ga-AABP3 (low-dose group); A, B, C, D, E, F, G, H, I and J refer to heart, liver, spleen, lung, kidney, stomach, small intestine, muscle, femur and brain respectively;

[0039] Fig.11 for 68 HE staining of important organs of Ga-AABP3 (medium dose group); A, B, C, D, E, F, G, H, I and J refer to heart, liver, spleen, lung, kidney, stomach, small intestine, muscle, femur and brain respectively;

[0040] Fig.12 for 68 HE staining of important organs of Ga-AABP3 (high-dose group); A, B, C, D, E, F, G, H, I and J refer to heart, liver, spleen, lung, kidney, stomach, small intestine, muscle, femur and brain respectively;

[0041] Fig.13 for 68 In vivo biodistribution profile of Ga-AABP3;

[0042] Fig.14 for 68 TNT plot of in vivo biodistribution of Ga-AABP3;

[0043] Fig.15 for 68 PET / CT imaging of Ga-AABP3 in healthy mice;

[0044] Fig.16 for 68 PET / CT imaging of Ga-AABP3 in tumor-bearing mice. DETAILED DESCRIPTION

[0045] It should be noted that the following detailed descriptions are exemplary and are intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used in the present invention have the same meanings as those commonly understood by those skilled in the art to which the present invention belongs.

[0046] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0047] The first typical embodiment of the present invention provides a marker precursor for bone metastasis, the structural formula of which is shown in formula (I):

[0048]

[0049] Formula (I).

[0050] A second typical embodiment of the present invention provides a method for preparing a marker precursor of bone metastasis described in the first aspect, comprising:

[0051] Boc-β-alanine reacts with phenylalanine to obtain intermediate 1;

[0052] Intermediate 1 reacts with alendronic acid to obtain intermediate 2;

[0053] Intermediate 2 reacts with the chelating agent tetraazacyclododecane tetraacetic acid-succinimidyl ester (DOTA-NHS) to obtain a labeled precursor of bone metastasis;

[0054] Wherein, the structural formula of intermediate 1 is shown in formula (II);

[0055]

[0056] Formula (II);

[0057] The structural formula of intermediate 2 is shown in formula (III);

[0058]

[0059] Formula (III).

[0060] In one or more embodiments, Boc-β-alanine and phenylalanine are dispersed in an organic solvent, and N,N,N',N'-tetramethyl-O-(N-succinimidyl) uronium tetrafluoroborate (TSTU) and N,N-diisopropylethylamine (DIEA) are added to carry out a condensation reaction to obtain intermediate 1.

[0061] Preferably, the organic solvent comprises N,N-dimethylformamide (DMF).

[0062] Preferably, the molar ratio of Boc-β-alanine, phenylalanine, N,N,N',N'-tetramethyl-O-(N-succinimidyl)uronium tetrafluoroborate and N,N-diisopropylethylamine is (0.8-1.2):(0.8-1.2):(0.8-1.2):(1.3-1.8), preferably 1:1:1:1.5.

[0063] Preferably, the condensation reaction is carried out with stirring at room temperature, and the reaction time is 2 to 4 h, preferably 3 h.

[0064] In one or more embodiments, intermediate 1 and alendronic acid are dispersed in an organic solvent, N,N,N',N'-tetramethyl-O-(N-succinimidyl) uronium tetrafluoroborate (TSTU) and N,N-diisopropylethylamine (DIEA) are added for condensation reaction, and then trifluoroacetic acid (TFA) is used to remove Boc protection to obtain intermediate 2.

[0065] Preferably, the organic solvent comprises N,N-dimethylformamide (DMF).

[0066] Preferably, the molar ratio of intermediate 1, alendronic acid, N,N,N',N'-tetramethyl-O-(N-succinimidyl) uronium tetrafluoroborate and N,N-diisopropylethylamine is (1-1.2):(0.8-1.2):(1.3-1.8):(1.8-2.2), preferably 1.1:1:1.5:2.

[0067] Preferably, the condensation reaction is carried out with stirring at room temperature, and the reaction time is 1.5 to 2.5 h, preferably 2 h.

[0068] In one or more embodiments, the intermediate 2 and the chelating agent DOTA-NHS are dispersed in an organic solvent, and N,N-diisopropylethylamine (DIEA) is added to carry out a condensation reaction to obtain a marker precursor for bone metastasis.

[0069] Preferably, the organic solvent comprises N,N-dimethylformamide (DMF).

[0070] Preferably, the molar ratio of intermediate 2, DOTA-NHS and N,N-diisopropylethylamine is (1-1.2):(1-1.5):(5-10), preferably 1:1.3:8.

[0071] Preferably, the condensation reaction is carried out with stirring at room temperature, and the reaction time is 15 to 20 h, preferably 16 h.

[0072] A third typical embodiment of the present invention provides a probe comprising the labeled precursor of bone metastasis described in the first aspect and / or the labeled precursor of bone metastasis prepared by the preparation method described in the second aspect and a radionuclide.

[0073] In one or more embodiments, the radionuclide comprises 18 F. 94 Tc, 99m Tc, 90 In, 111 In, 67 Ga, 68 Ga, 86 Y. 90 Y. 177 Lu, 151 Tb, 186 Re, 188 Re, 64 Cu, 67 Cu, 55 Co. 57 Co. 43 Sc, 44 Sc, 47 Sc, 225 Ac, 213 Bi, 212 Bi, 212 Pb, 227 Th, 153 Sm, 166 Ho, 152 Gd, 153 Gd, 157 Gd or 166 One of Dy; preferably 68 Ga.

[0074] More preferably, the structural formula of the probe is as shown in formula (IV),

[0075]

[0076] Formula (IV).

[0077] A fourth typical embodiment of the present invention provides a method for preparing the probe according to the third aspect, comprising:

[0078] After the radioactive nuclide is mixed and reacted with the labeling precursor of the bone metastasis, a probe is obtained.

[0079] A fifth typical embodiment of the present invention provides the use of the bone metastasis marker precursor described in the first aspect and / or the bone metastasis marker precursor prepared by the preparation method described in the second aspect and / or the probe of the third aspect and / or the probe prepared by the preparation method described in the fourth aspect in the preparation of products for detecting bone metastases.

[0080] A sixth typical embodiment of the present invention provides a product for detecting bone metastases, comprising the labeled precursor of bone metastases described in the first aspect and / or the labeled precursor of bone metastases prepared by the preparation method described in the second aspect and / or the probe of the third aspect and / or the probe prepared by the preparation method described in the fourth aspect.

[0081] In one or more embodiments, the product includes one or more of a reagent, a kit, a drug, and an imaging agent.

[0082] In order to enable those skilled in the art to more clearly understand the technical solution of the present invention, the technical solution of the present invention will be described in detail below in conjunction with specific embodiments.

[0083] Example 1

[0084] Figure 1 For the reaction route of the marker precursor of bone metastasis, refer to Figure 1 , a marker precursor for synthetic bone metastases.

[0085] Boc-β-alanine (75.684 mg, 1 eq, 0.4 mmol) and phenylalanine (66.076 mg, 1 eq, 0.4 mmol) were dispersed in N,N-dimethylformamide (DMF) (20 mL), and N,N,N',N'-tetramethyl-O-(N-succinimidyl) uronium tetrafluoroborate (TSTU) (120.42 mg, 1 eq, 0.4 mmol) and N,N-diisopropylethylamine (DIEA) (77.550 mg, 1.5 eq, 0.6 mmol) were added for condensation reaction (normal temperature, 3 h) to obtain intermediate 1 (119.351 mg, yield 88.7%).

[0086] Intermediate 1 (19.107 mg, 1.1 eq, 0.0568 mmol) and alendronic acid (12.854 mg, 1 eq, 0.0516 mmol) were dispersed in N,N-dimethylformamide (DMF) (20 mL), and N,N,N',N'-tetramethyl-O-(N-succinimidyl) uronium tetrafluoroborate (TSTU) (22.880 mg, 1.5 eq, 0.076 mmol) and N,N-diisopropylethylamine (DIEA) (13.339 mg, 2 eq, 0.1032 mmol) were added for condensation reaction (room temperature, 2 h), and then TFA was used for de-Boc protection (2 mL, room temperature, overnight) to obtain intermediate 2 (16.230 mg, yield 67.3%).

[0087] Intermediate 2 (4.674 mg, 1 eq, 0.010 mmol) and chelating agent DOTA-NHS (6.519 mg, 1.3 eq, 0.013 mmol) were dispersed in N,N-dimethylformamide (DMF) (5 mL), and N,N-diisopropylethylamine (DIEA) (10.340 mg, 8 eq, 0.08 mmol) was added for condensation reaction (normal temperature, 16 h) to obtain the final product of bone metastasis labeled precursor represented by formula (I) (5.934 mg, yield 69.5%). The bone metastasis labeled precursor represented by formula (I) is referred to as AABP3.

[0088] The ESI-MS mass spectrum of the labeled precursor AABP3 is shown in Figure 2 As shown, the experimental results show that the molecular weight of the labeled precursor AABP3 is consistent with the theoretical value, and its purity is higher than 98%.

[0089] The H NMR spectrum of the labeled precursor AABP3 is shown in Figure 3 shown.

[0090] Example 2

[0091] The labeled precursor AABP3 (10 nmol) was dissolved in 100 μL of NaOAc buffer (concentration: 0.25 M, pH: 4.0-4.6), and then 400 μL of 68 GaCl3 solution (2 mCi) was reacted at 95°C for 20 min to obtain the probe. 68 Ga-AABP3.

[0092] Radio-iTLC was used to characterize the probe 68 The radiochemical purity of Ga-AABP3 was tested, and the iTLC developing solvent was 0.1 M sodium citrate solution. Figure 4 As shown, the probe 68 The radiochemical purity of Ga-AABP3 is greater than 98%.

[0093] Example 3

[0094] In vitro stability studies:

[0095] 15 μL of the 68 Ga-AABP3 was added to 185 µL of PBS buffer (pH = 7.4) or human serum and incubated at 37 °C for 1.5 h. After incubation, PBS samples or blood samples were detected by Radio-iTLC.

[0096] The experimental results are as follows Figure 5 As shown, the experimental results show that in PBS samples or blood samples, 68The radiochemical purity of Ga-AABP3 did not change significantly and was greater than 95%, indicating 68 Ga-AABP3 has good stability in vitro.

[0097] Example 4

[0098] Hydrophilicity and lipophilicity study:

[0099] 5 µL (about 0.1 MBq) of the 68 Ga-AABP3 was diluted to 500 µL with HEPES buffer at pH = 7.4, and then 500 µL of n-octanol was added and shaken vigorously. Centrifuge thoroughly, take out equal volumes of liquid from the aqueous phase and the organic phase, continue shaking and centrifugation, and repeat 3 times. Finally, 100 µL of liquid was taken out from the aqueous phase and the organic phase, and the radioactivity counts were measured using a gamma counter. The lipid-water partition coefficient was calculated using the formula Log D = [Log (radioactivity counts in the organic phase / radioactivity counts in the aqueous phase)].

[0100] The experimental results show that 68 The Log D of Ga-AABP3 is 3.43 ± 0.20, which has good hydrophilicity.

[0101] Example 5

[0102] In vitro hydroxyapatite (HAP) binding assay:

[0103] 250 mg of HAP was divided into 5 groups, and each group was incubated in 1 mL of saline at room temperature for 24 hours. 68 Ga-AABP3 was added to the HAP suspension, vortexed thoroughly, incubated at room temperature for 10 minutes, and centrifuged for 3 minutes (12100×g). The supernatant and precipitate HAP were separated, and the precipitate HAP was washed twice with saline. The radioactivity counts in the supernatant and precipitate HAP were measured by a gamma counter. In vitro HAP binding rate = precipitate radioactivity count × 100% / (precipitate radioactivity count + supernatant radioactivity count).

[0104] The experimental results show that 68 The in vitro HAP binding rate of Ga-AABP3 = 93.84 ± 1.19%, indicating high in vitro HAP affinity.

[0105] Example 6

[0106] In vivo stability studies:

[0107] Five healthy female BALB / c mice aged 6 to 8 weeks were used to evaluate the 68The metabolic stability of Ga-AABP3 in vivo. Each mouse was injected with about 37.0 MBq of 68 Ga-AABP3, 1.5 h after injection, urine, blood, liver, and kidney samples were collected. Liver and kidney samples were fully ground, ethanol precipitated, and centrifuged for 10 min (12100×g) to obtain a clear supernatant. Blood samples were centrifuged for 10 min (12100×g) to obtain clear plasma. Radio-iTLC was used for detection and observation. 68 The radiochemical purity of Ga-AABP3 in different samples is shown in Figure 6 .

[0108] The experimental results show that after 1.5 h, 68 The stability of Ga-AABP3 in urine, blood, liver and kidney is higher than 95%, indicating 68 Ga-AABP3 has strong in vivo stability.

[0109] Example 7

[0110] Blood clearance experiment:

[0111] Five healthy female BALB / c mice aged 6 to 8 weeks were used to evaluate the 68 Blood metabolic characteristics of Ga-AABP3 in vivo. Each mouse was injected with about 3.7 MBq of Ga-AABP3 prepared in Example 2 via the tail vein. 68 Ga-AABP3, blood samples were collected at 1, 3, 5, 10, 15, 30, 60, 90, and 120 minutes after injection. The blood samples were weighed and their activity was measured using a gamma counter. The percentage of injected dose per gram of tissue (%ID / g) = radioactive counts of tissue / (total radioactive counts injected * mass of tissue). Simulated by DAS software 68 The distribution phase half-life and elimination phase half-life of Ga-AABP3. Figure 7 .

[0112] The drug concentration changes obtained by DAS software fitting reflect the summary of the distribution phase (α phase) and the elimination phase (β phase). The blood drug concentration in the distribution phase (α phase) drops rapidly after administration, which is the fast elimination phase. The drug concentration in the elimination phase (β phase) decreases proportionally according to the dynamic equilibrium law, which is the slow elimination phase. 68 The blood clearance curve of Ga-AABP3 conforms to the two-compartment model, and the half-life of the distribution phase (T 1 / 2α ) was 4.57 ± 2.69 minutes, and the elimination phase half-life (T 1 / 2β ) was 65.25 ± 7.04 minutes, and the blood metabolism time was moderate.

[0113] Example 8

[0114] In vivo toxicity test:

[0115] Twenty healthy female BALB / c mice aged 6 to 8 weeks were used to evaluate the 68 Blood metabolic characteristics of Ga-AABP3 in vivo. Twenty healthy female BALB / c mice aged 6 to 8 weeks were randomly divided into 4 groups, namely, control group, low-dose group, medium-dose group and high-dose group. The control group was injected with 0.2 mL of normal saline, and the low-dose group, medium-dose group and high-dose group were injected with 3.7, 18.5 and 37.0 MBq of Ga-AABP3 prepared in Example 2, respectively. 68 Ga-AABP3. The weight and general condition of the mice were monitored for 4 weeks. After 4 weeks of observation, blood routine, liver and kidney function tests were performed in each group, and then the mice were euthanized and the main tissues and organs were obtained for hematoxylin-eosin staining (HE staining). Figure 8 The HE staining results of different groups are shown in Figures 9 to 12 shown.

[0116] The results showed that all mice survived during the 4-week observation, and there were no abnormalities in mental and dietary conditions. No significant differences were found between the groups in body weight monitoring for 4 consecutive weeks, and HE pathological sections confirmed that there was no organ toxicity in all groups. The above results show that 68 Ga-AABP3 has no in vivo drug toxicity within the commonly used injection dose range (0-37.0 MBq).

[0117] Example 9

[0118] In vivo biodistribution studies:

[0119] Ten healthy female BALB / c mice aged 6 to 8 weeks were used to evaluate the 68 In vivo biodistribution characteristics of Ga-AABP3. Each mouse was injected with about 7.4 MBq of Ga-AABP3 via the tail vein. 68 Ga-AABP3. injection 68 Five mice were killed 0.5 h and 1.5 h after Ga-AABP3, and the tibia, femur, blood and other major organs and tissues were collected, weighed and the radioactivity count was measured. The %ID / g was calculated after correction for radioactive decay. The results are shown in Tables 1 and Fig.13 shown.

[0120] The %ID / g ratio (TNT) of femur to major organs was calculated, where T / L, T / K, T / M, and T / B refer to bone / liver, bone / kidney, bone / muscle, and bone / blood, respectively. The results are shown in Table 2 and Fig.14 shown.

[0121] Table 1 Injection into tibia, femur, blood and other major organs and tissues68 Radioactivity counting results of Ga-AABP3 after 0.5 h and 1.5 h

[0122]

[0123] The experimental results showed that the injection 68 After 0.5 h and 1.5 h of Ga-AABP3, the radioactive uptake in the tibia and femur was the highest, and the radioactive uptake increased with time. 68 Ga-AABP3 is mainly metabolized by the kidney. The radioactive uptake in other organs or tissues is relatively low. The above results show that 68 Ga-AABP3 has excellent bone affinity, is mainly metabolized by the kidney, and has low nonspecific uptake in other organs or tissues.

[0124] Table 2 %ID / g ratio of femur and major organs

[0125]

[0126] The experimental results showed that the injection 68 Compared with the TNT ratio of Ga-AABP3 0.5 h after injection 68 After 1.5h, T / K and T / M of Ga-AABP3 increased significantly, and T / L and T / B also increased to a certain extent. 68 Ga-AABP3 showed excellent bone affinity, low nonspecific uptake, and increased over time, with the TNT ratio further improved than before.

[0127] Example 10

[0128] 68 PET / CT imaging of Ga-AABP3 in healthy mice

[0129] Five healthy female BALB / c mice aged 6 to 8 weeks were taken, and each mouse was injected with about 7.4 MBq of the 68 Ga-AABP3. injection 68 After 0.5 h and 1.5 h of Ga-AABP3, the mice were anesthetized and small animal PET / CT imaging was performed. The PET / CT image data were reconstructed by Mediso Nucline NanoScan 3.00 software, and the maximum standard uptake value (SUVmax) in the region of interest was analyzed using Mediso InterViewFUSION 3.0 software to evaluate its osteophilicity. Fig.15 shown.

[0130] PET / CT imaging results showed a significant increase in bone uptake (especially in the joints and spine), and knee SUV max The uptake increased with time, reaching 2.11 ± 0.13 and 2.24 ± 0.16 at 0.5 h and 1.5 h, respectively. In addition to bones, significant uptake was also observed in the bladder, suggesting 68 Ga-AABP3 is metabolized through the urinary system. No significant uptake was observed in other organs or tissues.

[0131] Embodiment 11

[0132] 68 PET / CT imaging of Ga-AABP3 in tumor-bearing mice

[0133] Cell culture: A549 non-small cell lung cancer cell line was cultured in DMEM medium containing 10% calf serum in a 5% CO2, 37°C cell culture incubator.

[0134] Establishment of a mouse model of left tibial metastasis of non-small cell lung cancer: A549 non-small cell lung cancer cells were cultured in vitro, washed and centrifuged with serum-free medium, and 5×10 6 / mL cell concentration of serum-free suspension. 6-8 week-old BALB / c female nude mice were anesthetized and placed in supine position. The skin around the tibia was disinfected with iodine alcohol. A small incision was made perpendicular to the left tibia at the left knee joint, the patella was carefully exposed, and the puncture needle was used to puncture along the long axis of the left tibia. A549 cells (5×10 6 / mL). After injection, the needle hole was sealed with bone wax. The incision was carefully handled, the skin was sutured and disinfected. Tumor growth was monitored every day until three-dimensional CT confirmed that the tumor-bearing mouse model was successfully established.

[0135] Five tumor-bearing mice were selected and each mouse was injected with approximately 7.4 MBq of 68 Ga-AABP3. injection 68 After 30.5 h and 1.5 h of Ga-AABP, the mice were anesthetized and small animal PET / CT imaging was performed. The PET / CT image data were reconstructed by Mediso Nucline NanoScan 3.00 software, and the SUV in the region of interest was analyzed using Mediso InterView FUSION 3.0 software. max , and evaluate its bone affinity. Fig.16 shown.

[0136] The experimental results showed that the injection 68 After 0.5 h of Ga-AABP3, there was obvious radioactive uptake in the lesion, and SUV maxwas 2.64 ± 0.08. 1.5 h after injection, SUV max Increased to 2.67 ± 0.10, while uptake by other organs / tissues remained relatively low SUV max . 68 Ga-AABP3 has good bone affinity and low nonspecific uptake, and can be used for imaging of bone metastases.

[0137] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A marker precursor for bone metastasis, characterized in that: Its structural formula is shown in formula (I). Formula (I).

2. The method for preparing a marker precursor of bone metastasis according to claim 1, characterized in that: include: Boc-β-alanine reacts with phenylalanine to obtain intermediate 1; Intermediate 1 reacts with alendronic acid to obtain intermediate 2; Intermediate 2 reacts with the chelating agent tetraazacyclododecane tetraacetic acid-succinimidyl ester to obtain a labeled precursor of bone metastasis; Wherein, the structural formula of intermediate 1 is shown in formula (II); Formula (II); The structural formula of intermediate 2 is shown in formula (III); Formula (III).

3. The preparation method according to claim 2, characterized in that: Boc-β-alanine and phenylalanine are dispersed in an organic solvent, and N,N,N',N'-tetramethyl-O-(N-succinimidyl) uronium tetrafluoroborate and N,N-diisopropylethylamine are added to carry out a condensation reaction to obtain an intermediate 1; Intermediate 1 and alendronic acid are dispersed in an organic solvent, and N,N,N',N'-tetramethyl-O-(N-succinimidyl) uronium tetrafluoroborate and N,N-diisopropylethylamine are added for condensation reaction, and then trifluoroacetic acid is used for deprotection of Boc to obtain intermediate 2; The intermediate 2 and the chelating agent tetraazacyclododecane tetraacetic acid-succinimide ester are dispersed in an organic solvent, and N,N-diisopropylethylamine is added to carry out a condensation reaction to obtain a marker precursor of bone metastasis.

4. A probe, characterized in that: The method comprises the bone metastasis labeled precursor of claim 1 and / or the bone metastasis labeled precursor prepared by the preparation method of claim 2 or 3 and a radionuclide; the radionuclide is selected from 111 In, 67 Ga, 68 Ga, 86 Y. 90 Y. 177 Lu, 64 Cu, 67 Cu, 55 Co. 57 Co. 43 Sc, 44 Sc, 47 Sc, 225 Ac, 213 Bi, 212 Bi, 212 Pb, 153 Sm, 166 Ho, 153 Gd or 157 One of Gd.

5. The probe according to claim 4, characterized in that The radionuclide is 68 Ga.

6. The probe according to claim 5, characterized in that The structural formula of the probe is shown in formula (IV). Formula (IV).

7. The method for preparing a probe according to claim 5 or 6, characterized in that: include: After the radioactive nuclide is mixed and reacted with the labeling precursor of the bone metastasis, a probe is obtained.

8. Use of the labeled precursor of bone metastasis according to claim 1 and / or the labeled precursor of bone metastasis prepared by the preparation method according to claim 2 or 3 and / or the probe according to claim 5 or 6 and / or the probe prepared by the preparation method according to claim 7 in preparing products for detecting bone metastasis.

9. A product for detecting bone metastases, characterized in that: It comprises the bone metastasis marker precursor according to claim 1 and / or the bone metastasis marker precursor prepared by the preparation method according to claim 2 or 3 and / or the probe according to claim 5 or 6 and / or the probe prepared by the preparation method according to claim 7.

10. The product for detecting bone metastasis according to claim 9, characterized in that: The product includes: one or more of reagents, kits, drugs and imaging agents.

Images