阅读说明：本技术 一种载氧微球及其制备方法和应用 (Oxygen-carrying microsphere and preparation method and application thereof ) 是由 彭盛 张福君 于 2020-02-28 设计创作，主要内容包括：本发明公开了一种载氧微球,包括载体基质、放射性核素和产氧材料,载体基质包裹产氧材料,放射性核素由载体基质包裹或与载体基质表面螯合。本发明还公开了载氧微球的制备方法以及载氧微球在制备治疗肿瘤放射栓塞的药物中的应用。本发明的载氧微球具备自身供给氧气的能力,从而缓解或消除肿瘤放射栓塞治疗过程中栓塞效应造成肿瘤区域缺氧情况,最终提高治疗效果及减少由于缺氧造成的不良反应。(The invention discloses an oxygen-carrying microsphere, which comprises a carrier matrix, a radionuclide and an oxygen-producing material, wherein the oxygen-producing material is wrapped by the carrier matrix, and the radionuclide is wrapped by the carrier matrix or chelated with the surface of the carrier matrix. The invention also discloses a preparation method of the oxygen-carrying microsphere and application of the oxygen-carrying microsphere in preparing a medicament for treating tumor radio-embolism. The oxygen-carrying microsphere has the capability of supplying oxygen by itself, so that the condition of hypoxia in a tumor region caused by embolism effect in the tumor radioactive embolism treatment process is relieved or eliminated, the treatment effect is finally improved, and adverse reactions caused by hypoxia are reduced.)

1. an oxygen-carrying microsphere comprising a carrier matrix, a radionuclide and an oxygen generating material, said carrier matrix encapsulating said oxygen generating material, said radionuclide being encapsulated by said carrier matrix or chelated to a surface of said carrier matrix.

2. The oxygen-carrying microsphere of claim 1, wherein the oxygen-carrying microsphere comprises from 9 to 90 wt% of the carrier matrix, from 5 to 90 wt% of the radionuclide, and from 1 to 80 wt% of the oxygen generating material.

3. The oxygen-carrying microsphere of claim 1, wherein the carrier matrix is a high molecular polymer and/or a protein.

4. The oxygen-carrying microsphere of claim 1, wherein the oxygen generating material is at least one of oxygen, an inorganic peroxide and an organic polymeric material containing a peroxide bond.

5. The oxygen-carrying microsphere of claim 1, wherein the radionuclide is:

1) radioactive element⁹⁰Y、³²P、¹⁸F、¹⁴⁰La、¹⁵³Sm、¹⁶⁵Dy、¹⁶⁶Ho、¹⁶⁹Er、¹⁶⁹Yb、¹⁷⁷Lu、¹⁸⁶Re、¹⁸⁸Re、¹⁰³Pd、¹⁹⁸Au、¹⁹²Ir、⁹⁰Sr、¹¹¹In and⁶⁷at least one of Ga;

2) an inorganic salt of the radioactive element;

3) a metal oxide of the radioactive element; or

4) An organic complex of the radioactive element.

6. The oxygen-carrying microsphere of claim 1, wherein the oxygen generating material is a mixed gas of oxygen and a fluorine-containing gas, and the fluorine-containing gas accounts for 0.5-50% of the mixed gas by volume.

7. The oxygen-carrying microsphere of claim 6, wherein the fluorine-containing gas is at least one of sulfur hexafluoride, perfluoropropane, perfluorobutane, perfluoropentane, and perfluorohexane.

8. The method for preparing oxygen-carrying microspheres of any one of claims 1 to 7, wherein the oxygen-carrying microspheres are prepared by an emulsion solvent evaporation method, a chemical crosslinking method or a heated protein denaturation method.

9. Use of the oxygen-carrying microspheres of any one of claims 1 to 7 for the preparation of a medicament for the treatment of tumor radioembolism.

10. A medicament for the treatment of tumor radioembolism, which comprises the oxygen-carrying microspheres as claimed in any one of claims 1 to 7.

Technical Field

The invention relates to the technical field of tumor treatment, in particular to an oxygen-carrying microsphere and a preparation method and application thereof.

Background

Blood supply to normal liver is 75% from portal vein and 25% from hepatic artery. Whereas the blood supply for hepatocellular carcinoma (HCC) comes almost entirely from the hepatic artery. By using the unique blood supply mode, the radionuclide-labeled microspheres can selectively stay in hepatic artery supplying blood to liver cancer tissue, and the carried nuclide releases radioactive rays to cause the death of peripheral tumor cells, while the normal hepatic cells far away from the microspheres are hardly damaged.

Two types of radioactive microspheres, each developed by NORDION, Canada, are currently in clinical useDeveloped by Sirtex Medical in AustraliaThe physical properties and mode of production of the two microspheres are different, but they both use β radiation released by the radionuclide yttrium-90 to exert therapeutic effects.Is a glass microsphere containing non-radioactive yttrium-89, the yttrium-89 in the glass microsphere is activated into radioactive yttrium-90 by neutron activation before use, and the specific production process is disclosed in the patent US 4,789,501¹And US 5,011,677²。Activated yttrium-90 ions are adsorbed using ion exchange resin microspheres and immobilized at the adsorption sites in their phosphate form (US 20070253898 a1 and US 20100215571 a 1).

In radiotherapy, the permanent destruction of the DNA strands by radiation requires the presence of oxygen, and the radioactive microspheres need to be controlled to a size between 20-40 μm in diameter to avoid significant ischemic and embolic effects, but at the same time are sufficiently large to not pass through the capillary network into the venous circulation. Although the embolization effect of the radiomicrospheres was not expected to be significant by careful design of the size of the embolization microspheres, several studies have reported that the Vascular Endothelial Growth Factor (VEGF) associated with embolization effects increases rapidly and treatment results are poor after radioimmunoassay of tumors in patients^3-4. The embolization effect of the microspheres can cause local hypoxia of liver cancer tissues, thereby increasing the radioresistance of liver cancer cells. To kill tumor cells, the radiation dose has to be increased to increase the amount of microspheres injected. Furthermore, the embolization effect of the radio-embolization therapy induces the body to systemically release angiogenic factors that promote the growth of untreated lesions or extrahepatic (micro) metastases and may affect the survival of the patient.

To inhibit the angiogenic response due to embolic effects and to improve therapeutic efficacy, several studies have attempted to combine Sorafenib (Sorafenib) during the course of yttrium-90 radiotherapeutic embolization^4-5. Sorafenib is a multi-kinase inhibitor which targets a plurality of factors involved in angiogenesis and hepatoma cell proliferation, including VEGF receptors, PDGF, RAF-1 and the like, and is used to inhibit an angiogenic response caused by an embolic effect and to improve a therapeutic effect.

Conventional radio-embolic microspheres such asAnd

with only the radionuclide and its corresponding carrier matrix. The microspheres can stay in capillaries of a tumor part due to the designed physical size so as to be focused on the tumor part in a targeted manner, but the embolism effect caused by the microspheres can cause local hypoxia of tumor tissues, so that the radioresistance of tumor cells is increased. To kill the tumor cells, the radiation dose has to be increased. In addition, embolic effects induce the body to systemically release angiogenic factors. This factor promotes the growth of untreated lesions and/or extrahepatic (micro) metastases. The invention mainly solves the problems of poor curative effect and adverse reaction caused by local hypoxia of a tumor region in the traditional radio-embolism treatment process.

Disclosure of Invention

Based on the above problems, the present invention aims to overcome the defects of the prior art and provide an oxygen carrying microsphere for tumor radioimmunoassay, which has the ability of supplying oxygen by itself, so as to alleviate or eliminate the hypoxia condition of the tumor region caused by the embolization effect in the process of tumor radioimmunoassay, and finally improve the treatment effect and reduce the adverse reaction caused by hypoxia.

In order to achieve the purpose, the technical scheme adopted by the invention comprises the following aspects:

in a first aspect, the present invention provides an oxygen-carrying microsphere comprising a carrier matrix, a radionuclide, and an oxygen-generating material, the carrier matrix encapsulating the oxygen-generating material, the radionuclide being encapsulated by the carrier matrix or chelated to a surface of the carrier matrix. Preferably, the carrier matrix has a hollow cavity, which is filled with an oxygen generating material or/and a radionuclide. Wherein, the oxygen-producing material is used for slowing down or eliminating the local hypoxia condition of the tumor area caused by the embolism effect in the radioactive embolism treatment process, and improving the sensitivity of tumor cells to rays, thereby improving the radiotherapy effect.

Preferably, the content of the carrier matrix in the oxygen-carrying microspheres is 9-90 wt%, the content of the radionuclide is 5-90 wt%, and the content of the oxygen-generating material is 1-80 wt%. More preferably, the carrier matrix in the oxygen-carrying microsphere is poly (lactide-glycolide) copolymer (PLGA, molecular weight: 20,000), the content is about 20 wt%, and the radionuclide is¹⁷⁷Lu、¹⁶⁶Ho or⁹⁰The content of one of Y is 55 wt%, the oxygen generating material is calcium peroxide, and the mass ratio of the oxygen generating material to the microspheres is about 25 wt%. Particularly, when the content of the carrier matrix (PLGA) in the oxygen-carrying microsphere is 20 wt%, the content of the radionuclide is 55 wt%, and the content of the oxygen-generating material (calcium peroxide) is 25 wt%, the therapeutic effect is best when the oxygen-carrying microsphere is used for treating tumor radioactive embolism.

In one embodiment, the oxygen-carrying microspheres have a carrier matrix content of 16 wt%, a radionuclide content of 55 wt%, and a calcium peroxide content of 29 wt%.

In one embodiment, the oxygen-carrying microspheres have a carrier matrix content of 23 wt%, a radionuclide content of 55 wt%, and a calcium peroxide content of 22 wt%.

In one embodiment, the oxygen-carrying microspheres have a carrier matrix content of 25.7 wt%, a radionuclide content of 55 wt%, and a calcium peroxide content of 19.3 wt%.

Preferably, the carrier matrix is a high molecular polymer and/or a protein; more preferably, the carrier matrix is a biodegradable polymer, preferably an aliphatic polylactone, a binary or ternary random or block copolymer between lactones, a binary or ternary random or block copolymer between a lactone and a polyether; the protein is preferably human serum albumin or gelatin.

Preferably, the oxygen generating material is at least one of oxygen, an inorganic peroxide and an organic polymer material containing a peroxide bond. More preferably, the inorganic peroxides include, but are not limited to, Sodium Percarbonate (SPC), calcium peroxide (CaO)₂) Magnesium peroxide (MgO)₂) And hydrogen peroxide (H)₂O₂) And the like.

Preferably, the radionuclide is:

1) radioactive element⁹⁰Y、³²P、¹⁸F、¹⁴⁰La、¹⁵³Sm、¹⁶⁵Dy、¹⁶⁶Ho、¹⁶⁹Er、¹⁶⁹Yb、¹⁷⁷Lu、¹⁸⁶Re、¹⁸⁸Re、¹⁰³Pd、¹⁹⁸Au、¹⁹²Ir、⁹⁰Sr、¹¹¹In and⁶⁷at least one of Ga;

2) an inorganic salt of the radioactive element;

3) a metal oxide of the radioactive element; or

4) An organic complex of the radioactive element.

Preferably, the oxygen generating material is a mixed gas of oxygen and a fluorine-containing gas, and the fluorine-containing gas accounts for 0.5-50% of the mixed gas by volume. Alternatively, the oxygen generating material is preferably a perfluorocarbon having an oxygen adsorbing ability and a medium boiling point (60 to 160 ℃), such as perfluoropentane, perfluorohexane, perfluoroheptane, perfluorooctane, perfluorononane, perfluorooctane, perfluorobromooctane, perfluoro-15-crown-5-ether, or the like.

Preferably, the fluorine-containing gas is at least one of sulfur hexafluoride, perfluoropropane, perfluorobutane, perfluoropentane, and perfluorohexane.

In a second aspect, the invention provides a preparation method of the oxygen-carrying microsphere, which adopts an emulsion solvent evaporation method, a chemical crosslinking method or a heating protein denaturation method to prepare the oxygen-carrying microsphere.

In a third aspect, the invention provides the use of said oxygen-carrying microspheres in the preparation of a medicament for the treatment of tumor radioimmunoassay.

In a fourth aspect, the present invention provides a medicament for the treatment of tumor radioembolism, which comprises the oxygen carrying microsphere.

In conclusion, the beneficial effects of the invention are as follows:

the invention provides an oxygen-carrying microsphere for tumor radio-embolization treatment for the first time and a preparation method thereof, compared with the existing radio-embolization microsphere such as

Andthe novel embolism microsphere only has radionuclide and corresponding carrier matrix thereof, has the capability of supplying oxygen by itself, thereby relieving or eliminating the hypoxia condition of a tumor area caused by embolism effect in the tumor radio-embolism treatment process, finally improving the treatment effect and reducing the adverse reaction caused by hypoxia.

Drawings

FIG. 1 is a schematic illustration of the encapsulation of various oxygen generating materials, wherein (A) oxygen is filled in the hollow cavity of the microsphere; (B) the perfluorinated oil is wrapped in the middle of the carrier matrix to form microspheres with a core-shell structure; (C) the peroxide nanoparticles are embedded between carrier matrices;

FIG. 2 is a schematic diagram of the embedding of different nuclides, wherein (A) inorganic salts of the nuclides are embedded in the hollow cavities of the microspheres; (B) nuclide nanoparticles or organic complexes thereof are embedded between carrier matrices; (C) nuclides are chelated on the chelating groups on the surfaces of the microspheres;

FIG. 3(A) is a schematic view of a binding structure of a support matrix and a chelating group; (B) chemical structural formulas of different chelating groups;

FIG. 4 is a synthetic scheme of a carrier matrix PLGA-PEG-DOTA incorporating coordinating groups;

FIG. 5 is a drawing of the polymer PLGA-PEG-DOTA¹H NMR spectrum;

FIG. 6 is an optical image of an oxygen-carrying embolic microsphere;

FIG. 7 is the oxygen release curve of oxygen-implanted embolized microspheres in phosphate buffer.

Detailed Description

In some embodiments, the present invention provides an oxygen-carrying microsphere for tumor radioimmunoassay treatment, which comprises three components, namely an oxygen generating material, a radionuclide and a carrier matrix, wherein:

1) oxygen generating material

The oxygen generating material refers to a material which can provide oxygen directly or through some chemical reaction, such as oxygen, inorganic peroxide or organic polymer material containing peroxy bond, and the like, and the content of the oxygen generating material in the oxygen carrying microsphere is 1-80 wt%.

In some cases, the oxygen generating material may be oxygen directly, as shown in FIG. 1-A, stored in the interstices of hollow or porous radioactive microspheres, which then slowly releases its entrained oxygen to the tumor environment by physical diffusion. In order to control the release rate of oxygen, one or more fluorine-containing gases, such as sulfur hexafluoride, perfluoropropane, perfluorobutane, perfluoropentane, perfluorohexane, etc., may be mixed into the oxygen in a certain proportion (0.5% to 50%).

In some cases, the oxygen generating material is a perfluorocarbon having oxygen adsorbing capacity and a medium boiling point (60-160 ℃), such as perfluoropentane, perfluorohexane, perfluoroheptane, perfluorooctane, perfluorononane, perfluorooctane, perfluorobromooctane, perfluoro-15-crown-5-ether, and the like. As shown in FIG. 1-B, perfluorocarbons are wrapped in a carrier matrix to form microspheres with a core-shell structure.

In some cases, the oxygen generating material is an inorganic peroxy compound, including but not limited to Sodium Percarbonate (SPC), calcium peroxide (CaO)₂) Magnesium peroxide (MgO)₂) And hydrogen peroxide (H)₂O₂) And the like. Inorganic peroxidation as shown in FIG. 1-CThe substance is embedded between microsphere matrixes as solid nanoparticles (such as calcium peroxide nanoparticles) or filled in the cavities of the hollow microspheres as liquid state (such as hydrogen peroxide).

2) Radionuclides

Radionuclide refers to⁹⁰Y、³²P、¹⁸F、¹⁴⁰La、¹⁵³Sm、¹⁶⁵Dy、¹⁶⁶Ho、¹⁶⁹Er、¹⁶⁹Yb、¹⁷⁷Lu、¹⁸⁶Re、¹⁸⁸Re、¹⁰³Pd、¹⁹⁸Au、¹⁹²Ir、⁹⁰Sr、¹¹¹In and⁶⁷ga and the like, and the content of the Ga accounts for 5-90 wt% of the oxygen-carrying microspheres. The radionuclide may be encapsulated in the microsphere in the form of its inorganic salt, metal oxide or organic complex.

In some cases, as shown in FIGS. 2-A and 2-B, the nuclide is first encapsulated between the carrier matrices of the microspheres or in the hollow cavities formed by the carrier matrices in the form of its inorganic salts, metal oxides, or organic complexes. Before use, the nuclide carried in the microsphere is excited to be radioactive by neutron radiation treatment.

In some cases, the radionuclide ions are bound to chelating sites on the surface of the microspheres, such as DOTA, DATP, and the like.

3) Carrier matrix

The carrier matrix is used for wrapping or carrying radionuclide and oxygen-producing material, and is generally high molecular polymer (such as polymethyl methacrylate, polyvinyl alcohol, poly (lactide-glycolide) copolymer) or protein (such as human serum albumin, gelatin, etc.), and the content of the high molecular polymer in the oxygen-carrying microspheres is 10-90 wt%.

In some cases, the carrier matrix is a biodegradable polymer, which is an aliphatic polylactone, a binary or ternary random or block copolymer between lactones and polyethers (molecular weight 5000-500000), such as Polylactide (PLA), Polycaprolactone (PCL), poly (lactide-glycolide) copolymer (PLGA), poly (lactide-caprolactone) copolymer (PLC), and poly (lactide-glycolide-polyglycol ether) copolymer (PLGE), and the like.

In some cases, the polymer may require chemical modification to bind one or more chemical structures for chelating radionuclides, as shown in FIG. 3-A, typically with the addition of a spacer group between the chelating group and the polymer. The spacer group is typically polyethylene glycol (PEG) with a molecular weight of 300-500, and the chelating group is typically DOTA, DTAP or derivatives thereof, and the chemical structure thereof is shown in FIG. 3-B.

4) Preparation of embolizing microspheres

The oxygen carrying microsphere for treating embolism is prepared by emulsion solvent evaporation, chemical crosslinking, heating protein denaturation or other methods according to the chemical and physical characteristics of the material containing the nuclear substance, the oxygen generating material and the carrier matrix.

In some cases, the oxygen-carrying microspheres are prepared by an emulsion solvent evaporation process. Generally, the nuclear-containing material (nuclide organic complex or inorganic nanoparticles), the oxygen-generating material, and the carrier matrix are dissolved or uniformly dispersed in a water-insoluble organic solvent; then preparing the organic solution into microdroplets with the diameter of 10-200 mu m in an aqueous solution containing a surfactant by mechanical stirring, ultrasonic emulsification, membrane emulsification or microfluidization emulsification, and the like, and stirring the emulsion to evaporate the organic solvent to finally obtain the oxygen-carrying microspheres.

In some cases, the oxygen-carrying microspheres are prepared by evaporation of a W/O/W multiple emulsion solvent, the core-containing material (inorganic salt) is dissolved in an aqueous phase, emulsified in an organic solvent in which the carrier matrix or the oxygen-generating material is dissolved, and then the emulsion is emulsified a second time in an aqueous solution containing a surfactant to prepare droplets having a diameter of between 10 and 200 μm, and the emulsion is stirred to evaporate the solvent to obtain the oxygen-carrying microspheres.

In some cases, the oxygen-carrying microspheres are prepared by a chemical crosslinking method in which a core-containing material (nuclide organic complex, or inorganic nanoparticles), an oxygen-generating material, and a carrier matrix are dissolved or uniformly dispersed in a water-insoluble organic solvent, and a crosslinking agent is added to the solvent, and then emulsified into droplets in an aqueous solution containing a surfactant, and the droplets are cured to form the oxygen-carrying microspheres by heating or by adding a catalyst to the aqueous phase to trigger a reaction.

To better illustrate the objects, aspects and advantages of the present invention, the present invention will be further described with reference to the accompanying drawings and specific embodiments. Unless otherwise specified, the experimental methods in the present invention are all conventional methods.