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WO2023019978A1 - 一种MOFs包被心肌细胞核壳结构的制备方法 - Google Patents

一种MOFs包被心肌细胞核壳结构的制备方法 Download PDF

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WO2023019978A1
WO2023019978A1 PCT/CN2022/085998 CN2022085998W WO2023019978A1 WO 2023019978 A1 WO2023019978 A1 WO 2023019978A1 CN 2022085998 W CN2022085998 W CN 2022085998W WO 2023019978 A1 WO2023019978 A1 WO 2023019978A1
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mofs
cardiomyocyte
coated
shell structure
core
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李晓琳
陈伟
张亮
龚涛
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Shenzhen Polytechnic
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Shenzhen Polytechnic
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    • C—CHEMISTRY; METALLURGY
    • C12—BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
    • C12N—MICROORGANISMS OR ENZYMES; COMPOSITIONS THEREOF; PROPAGATING, PRESERVING, OR MAINTAINING MICROORGANISMS; MUTATION OR GENETIC ENGINEERING; CULTURE MEDIA
    • C12N5/00—Undifferentiated human, animal or plant cells, e.g. cell lines; Tissues; Cultivation or maintenance thereof; Culture media therefor
    • C12N5/0012—Cell encapsulation
    • C—CHEMISTRY; METALLURGY
    • C12—BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
    • C12N—MICROORGANISMS OR ENZYMES; COMPOSITIONS THEREOF; PROPAGATING, PRESERVING, OR MAINTAINING MICROORGANISMS; MUTATION OR GENETIC ENGINEERING; CULTURE MEDIA
    • C12N5/00—Undifferentiated human, animal or plant cells, e.g. cell lines; Tissues; Cultivation or maintenance thereof; Culture media therefor
    • C12N5/06—Animal cells or tissues; Human cells or tissues
    • C12N5/0602—Vertebrate cells
    • C12N5/0652—Cells of skeletal and connective tissues; Mesenchyme
    • C12N5/0657—Cardiomyocytes; Heart cells
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J13/00—Colloid chemistry, e.g. the production of colloidal materials or their solutions, not otherwise provided for; Making microcapsules or microballoons
    • B01J13/02—Making microcapsules or microballoons
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J13/00—Colloid chemistry, e.g. the production of colloidal materials or their solutions, not otherwise provided for; Making microcapsules or microballoons
    • B01J13/02—Making microcapsules or microballoons
    • B01J13/04—Making microcapsules or microballoons by physical processes, e.g. drying, spraying
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J13/00—Colloid chemistry, e.g. the production of colloidal materials or their solutions, not otherwise provided for; Making microcapsules or microballoons
    • B01J13/02—Making microcapsules or microballoons
    • B01J13/20—After-treatment of capsule walls, e.g. hardening
    • C—CHEMISTRY; METALLURGY
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    • C12N2500/00—Specific components of cell culture medium
    • C12N2500/05—Inorganic components
    • C12N2500/10—Metals; Metal chelators
    • C12N2500/20—Transition metals
    • C12N2500/22—Zinc; Zn chelators
    • C—CHEMISTRY; METALLURGY
    • C12—BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
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    • C12N2533/00—Supports or coatings for cell culture, characterised by material
    • C12N2533/30—Synthetic polymers

Definitions

  • the invention relates to a method for coating cardiomyocytes.
  • Cardiomyocytes can generate spontaneous, rhythmic contraction without any external assistance, so it is relatively easy to use cardiomyocytes to fabricate biohybrid microrobots. Given that the size of a single cardiomyocyte is about 100 ⁇ m and its ability to contract autonomously, a single cardiomyocyte can be used as a driver for a microrobot on the scale of hundreds of microns. This will provide new ideas for solving the energy supply and nutrition supply problems of micro-robots in special working environments (such as human body).
  • the purpose of the present invention is to solve the problems of lack of physical protection, nutrient supply channel and short life cycle of existing bio-hybrid micro-robots, and provide a preparation method of MOFs-coated cardiomyocyte core-shell structure.
  • a preparation method of MOFs coated cardiomyocyte core-shell structure is completed according to the following steps:
  • step 2 Put the cell culture flask or cell culture dish in step 2 into a CO2 incubator with a temperature of 37°C for digestion, then add medium to terminate the digestion, and obtain a cell suspension;
  • the cell suspension is centrifuged, and the supernatant is discarded to obtain a cell pellet
  • the suspension cells obtained in step 5 are centrifuged, and the cell pellet is collected; the cell pellet is resuspended using fresh medium, and then transferred to a new cell culture bottle or cell culture dish for passage, and the passage ratio is 1:(2 ⁇ 8);
  • the concentration of the Zn(NO 3 ) 2 ⁇ 6H 2 O aqueous solution in step 7 is 1-10 g/L;
  • the concentration of the 2-methylimidazole aqueous solution described in step 7 is 5 ⁇ 20g/L;
  • step 6 Add the Zn(NO 3 ) 2 .6H 2 O aqueous solution and 2-methylimidazole aqueous solution to the cell culture bottle or cell culture dish obtained in step 6, then transfer the cell culture bottle or cell culture dish to Cultivate in a CO 2 incubator at 37°C for 1 to 7 days to obtain the MOFs-coated cardiomyocyte core-shell structure.
  • the present invention has prepared long-lived bio-hybrid micro-robots.
  • the physical protective layer of MOFs selectively permeates the nutrients and gases necessary for the survival of biological materials, and realizes the life support of biological materials.
  • the MOFs physical protection layer can selectively permeate the nutrients and gases necessary for the survival of biological materials, thereby maximally avoiding the influence of cytotoxic substances in the environment on the lifespan of cells and effectively prolonging the lifespan of cardiomyocytes.
  • the cell density of cardiomyocytes with MOFs shell was significantly higher than that of cardiomyocytes.
  • the invention can obtain a MOFs-coated cardiomyocyte core-shell structure.
  • Fig. 1 is a microscope photo enlarged by 100 times
  • a and b in Fig. 1 are micrographs of cardiomyocytes in different directions after passage in step six of embodiment one
  • c and d are MOFs coated cardiomyocyte nuclei obtained in step eight of embodiment one Microscopic pictures of the shell structure;
  • Figure 2 is a microscopic photo of cardiomyocytes.
  • a is a 40-fold microscopic photo of HL-1 mouse cardiomyocytes cultured for 7 days
  • b is the MOFs obtained in step 8 of Example 1 after being cultured for 7 days with the core-shell structure of cardiomyocytes Microscope picture at 40X magnification.
  • Embodiment 1 In this embodiment, a method for preparing a MOFs-coated cardiomyocyte core-shell structure is completed according to the following steps:
  • step 2 Put the cell culture flask or cell culture dish in step 2 into a CO2 incubator with a temperature of 37°C for digestion, then add medium to terminate the digestion, and obtain a cell suspension;
  • the cell suspension is centrifuged, and the supernatant is discarded to obtain a cell pellet
  • the suspension cells obtained in step 5 are centrifuged, and the cell pellet is collected; the cell pellet is resuspended using fresh medium, and then transferred to a new cell culture bottle or cell culture dish for passage, and the passage ratio is 1:(2 ⁇ 8);
  • the concentration of the Zn(NO 3 ) 2 ⁇ 6H 2 O aqueous solution in step 7 is 1-10 g/L;
  • the concentration of the 2-methylimidazole aqueous solution described in step 7 is 5 ⁇ 20g/L;
  • the HL-1 mouse cardiomyocyte culture medium described in Step 1 of this embodiment was purchased from Hunan Fenghui Biotechnology Co., Ltd.
  • Embodiment 2 This embodiment differs from Embodiment 1 in that: the number of cleanings described in step 1 is 1 to 2 times. Other steps are the same as in the first embodiment.
  • Specific embodiment three the difference between this embodiment and specific embodiment one or two is: the volume fraction of CO in the CO incubator described in step three is 5%; the culture medium described in step three is The mass fraction consists of: 90% DMEM high glucose, 9% fetal bovine serum and 1% double antibody; the concentration of the double antibody is 100U/mL. Other steps are the same as those in Embodiment 1 or 2.
  • Embodiment 5 The difference between this embodiment and Embodiment 1 to Embodiment 4 is that the digestion time in step 3 is 0.5 min to 2 min. Other steps are the same as those in Embodiments 1 to 4.
  • Embodiment 6 This embodiment differs from Embodiment 1 to Embodiment 5 in that: the centrifugation speed described in step 4 is 500r/min-2000r/min, and the centrifugation time is 3min-6min. Other steps are the same as those in Embodiments 1 to 5.
  • Specific embodiment seven the difference between this embodiment and one of specific embodiments one to six is: the volume fraction of CO in the CO incubator described in step five is 5%; The fraction composition is: 90% DMEM high glucose, 9% fetal bovine serum and 1% double antibody; the concentration of the double antibody is 100U/mL. Other steps are the same as those in Embodiments 1 to 6.
  • Embodiment 8 The difference between this embodiment and Embodiments 1 to 7 is that the culture medium described in step 6 consists of 90% DMEM high glucose, 9% fetal bovine serum and 1% double antibody by mass fraction. Composition; the concentration of the double antibody is 100U/mL; the centrifugation speed in step 6 is 500r/min-2000r/min, and the centrifugation time is 3min-6min. Other steps are the same as those in Embodiments 1 to 7.
  • Specific embodiment nine the difference between this embodiment and specific embodiment one to eight is: the volume fraction of CO in the CO incubator described in step eight is 5%; the Zn( NO3 described in step eight ) 2 ⁇ The volume ratio of 6H 2 O aqueous solution to cell culture medium is 6.25 ⁇ 10 -5 to 1.67 ⁇ 10 -3 .
  • Other steps are the same as those in Embodiments 1 to 8.
  • Embodiment 10 The difference between this embodiment and Embodiments 1 to 9 is that the volume ratio of the 2-methylimidazole aqueous solution to the cell culture medium in Step 8 is 6.25 ⁇ 10 -5 to 1.67 ⁇ 10 - 3 . Other steps are the same as those in Embodiments 1 to 9.
  • Embodiment 1 A kind of preparation method of MOFs coated cardiomyocyte core-shell structure is completed according to the following steps:
  • the HL-1 mouse cardiomyocyte culture medium described in step 1 was purchased from Hunan Fenghui Biotechnology Co., Ltd.;
  • step 3 Put the cell culture flask in step 2 into a CO 2 incubator at 37°C for 0.5 min to digest, then add 6 mL of medium to stop the digestion, and obtain a cell suspension;
  • the volume fraction of CO in the CO incubator described in step 3 is 5%;
  • the medium described in step 3 is composed by mass fraction: 90% DMEM high glucose, 9% fetal bovine serum and 1% double antibody; the concentration of the double antibody is 100U/mL;
  • the centrifugal speed described in step 4 is 1000r/min, and the centrifugal time is 4min;
  • the volume fraction of CO in the CO incubator described in step five is 5%;
  • the fresh medium described in step 5 is composed by mass fraction: 90% DMEM high glucose, 9% fetal bovine serum and 1% double antibody; the concentration of the double antibody is 100U/mL;
  • step 6 Centrifuge the suspended cells obtained in step 5, and collect the cell pellet; resuspend the cell pellet with 1 mL of fresh medium, and then transfer to a new T25 cell culture flask for passaging, with a passaging ratio of 1:2;
  • the fresh medium described in step 6 is composed by mass fraction: 90% DMEM high glucose, 9% fetal bovine serum and 1% double antibody; the concentration of the double antibody is 100U/mL;
  • the centrifugal speed described in step 6 is 1000r/min, and the centrifugal time is 4min;
  • the concentration of the Zn(NO 3 ) 2 ⁇ 6H 2 O aqueous solution described in step 7 is 5g/L;
  • the concentration of the 2-methylimidazole aqueous solution described in step 7 is 10g/L;
  • the volume fraction of CO 2 in the CO 2 incubator described in step eight is 5%.
  • Embodiment 2 A kind of preparation method of MOFs coated cardiomyocyte core-shell structure is completed according to the following steps:
  • the HL-1 mouse cardiomyocyte culture medium described in step 1 was purchased from Hunan Fenghui Biotechnology Co., Ltd.;
  • step 3 Put the cell culture flask in step 2 into a CO 2 incubator at 37°C for 1 min for digestion, then add 6 mL of medium to stop the digestion, and obtain a cell suspension;
  • the volume fraction of CO in the CO incubator described in step 3 is 5%;
  • the medium described in step 3 is composed by mass fraction: 90% DMEM high glucose, 9% fetal bovine serum and 1% double antibody; the concentration of the double antibody is 100U/mL;
  • the centrifugal speed described in step 4 is 2000r/min, and the centrifugal time is 4min;
  • the volume fraction of CO in the CO incubator described in step five is 5%;
  • the fresh medium described in step 5 is composed by mass fraction: 90% DMEM high glucose, 9% fetal bovine serum and 1% double antibody; the concentration of the double antibody is 100U/mL;
  • step 6 Centrifuge the suspended cells obtained in step 5, and collect the cell pellet; resuspend the cell pellet with 1 mL of fresh medium, and then transfer to a new T25 cell culture flask for passaging, with a passaging ratio of 1:4;
  • the fresh medium described in step 6 is composed by mass fraction: 90% DMEM high glucose, 9% fetal bovine serum and 1% double antibody; the concentration of the double antibody is 100U/mL;
  • the centrifugal speed described in step 6 is 2000r/min, and the centrifugal time is 4min;
  • the concentration of the Zn(NO 3 ) 2 ⁇ 6H 2 O aqueous solution described in step 7 is 10 g/L;
  • the concentration of the 2-methylimidazole aqueous solution described in step 7 is 20g/L;
  • the volume fraction of CO 2 in the CO 2 incubator described in step eight is 5%.
  • Fig. 1 is a microscopic photo enlarged by 100 times, a and b in the figure are microscopic photos of cardiomyocytes in different directions after passage in step 6 of embodiment 1, and c and d are MOFs obtained in step 8 of embodiment 1 coated with cardiomyocyte core shell Microscopic pictures of the structure;
  • FIG. 1 It can be seen from Figure 1 that through the in vitro culture of cardiomyocytes ( Figures a and b), it was found that the thickness of cardiomyocytes decreased with the progress of the culture process, while the spreading area gradually increased, and the two ends of cardiomyocytes would be in contact with the surrounding myocardium. The cell conducts membrane potential. It can be seen that cardiomyocytes can also complete periodic contraction in the culture medium environment in vitro.
  • Figures c and d are micrographs of cardiomyocytes co-cultured with MOFs precursors (metal ions and ligands) for 2 days. Compared with Figure a and Figure b, Figure d has significantly more crystal grains.
  • MOFs precursor solution is soluble in water, it shows that under the culture conditions of cardiomyocytes, the MOFs precursors can form MOFs particles on the surface of the cardiomyocyte membrane without affecting the morphology and biological activity of the cells. This study shows that the mineralization synthesis of MOFs particles is feasible.
  • Fig. 2 is the microscopic photograph of cardiomyocyte, among the figure a is the microscopic photograph enlarged 40 times after HL-1 mouse cardiomyocyte cultured for 7 days, and b is the MOFs coated cardiomyocyte core-shell structure obtained in step 8 of embodiment 1 magnified 40 times microscope photo.

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Abstract

本发明提供了一种MOFs包被心肌细胞核壳结构的制备方法，它涉及一种包被心肌细胞的方法。本发明的目的是要解决现有生物混合微机器人缺乏物理保护、养分供给通道和生命周期短的问题。方法：一、清洗；二、加入胰酶PBS溶液；三、消化；四、离心；五、培养；六、传代；七、配制Zn(NO 3) 2·6H 2O水溶液和2-甲基咪唑水溶液；八、加入Zn(NO 3) 2·6H 2O水溶液和2-甲基咪唑水溶液培养，得到MOFs包被心肌细胞核壳结构。在同样的培养条件下培养7天后，带有MOFs壳层的心肌细胞的细胞密度明显高于心肌细胞。本发明可获得一种MOFs包被心肌细胞核壳结构。

Description

一种MOFs包被心肌细胞核壳结构的制备方法
本申请要求于2021年8月18日提交中国专利局、申请号为202110948712.6、发明名称为“一种MOFs包被心肌细胞核壳结构的制备方法”的中国专利申请的优先权，其全部内容通过引用结合在本申请中。
技术领域
本发明涉及一种包被心肌细胞的方法。
背景技术
心肌细胞可以在没有任何外界辅助的情况下产生自发、有节律的收缩运动，因此利用心肌细胞制造生物混合微机器人是相对容易的。鉴于单个心肌细胞的尺寸为100μm左右，以及其具有可自主收缩的特性，单个心肌细胞可作为百微米级尺度微型机器人的驱动器。这将为解决微机器人在特殊工作环境中(如人体)的能量供给和营养供给问题提供新的思路。
然而，生物混合微机器人中的活体生物驱动材料往往生命周期短、环境鲁棒性差，且与人工微纳结构之间缺少适当的偶联机制，一直是限制生物混合微机器人生物医药应用的瓶颈问题。这主要是由于缺乏必要的养分供给和物理保护，以及有效的制备方法和理论，现有制备过程大多是先通过物理和化学的方法制备出特定结构的非生物机器人本体结构，然后利用特异亲和作用将生物材料黏附在非生物材料的表面，研究尺度受限于生物材料和非生物材料的尺寸，不利于从分子水平上理解并指导材料的优化设计。
发明内容
本发明的目的是要解决现有生物混合微机器人缺乏物理保护、养分供给通道和生命周期短的问题，而提供一种MOFs包被心肌细胞核壳结构的制备方法。
一种MOFs包被心肌细胞核壳结构的制备方法，是按以下步骤完成的：
一、弃去HL-1小鼠心肌细胞培养基的上清液，使用PBS缓冲液或生理盐水对HL-1小鼠心肌细胞进行清洗；
二、将清洗后的HL-1小鼠心肌细胞加入到细胞培养瓶或细胞培养皿 中，再加入质量分数为0.25％的胰酶PBS溶液，使质量分数为0.25％的胰酶PBS溶液覆盖在HL-1小鼠心肌细胞上面；
三、将步骤二中的细胞培养瓶或细胞培养皿放入温度为37℃的CO 2培养箱中消化，再加入培养基终止消化，得到细胞悬液；
四、将所述细胞悬液进行离心，弃上清液，得到细胞沉淀；
五、使用新鲜培养基对细胞沉淀进行重悬，再加入到细胞培养瓶或细胞培养皿中，将细胞培养瓶或细胞培养皿放入温度为37℃的CO 2培养箱中培养1天～7天，得到悬浮细胞；
六、步骤五得到悬浮细胞进行离心，收集细胞沉淀；使用新鲜培养基对所述细胞沉淀进行重悬，再转移到新的细胞培养瓶或细胞培养皿中传代，传代比例为1:(2～8)；
七、配制Zn(NO 3) 2·6H 2O水溶液和2-甲基咪唑水溶液；
步骤七中所述的Zn(NO 3) 2·6H 2O水溶液的浓度为1～10g/L；
步骤七中所述的2-甲基咪唑水溶液的浓度为5～20g/L；
八、向步骤六中得到的细胞培养瓶或细胞培养皿中分别加入所述Zn(NO 3) 2·6H 2O水溶液和2-甲基咪唑水溶液，再将细胞培养瓶或细胞培养皿转移到温度为37℃的CO 2培养箱中培养1天～7天，得到MOFs包被心肌细胞核壳结构。
本发明的原理：
本发明为了克服生物混合微机器人缺乏物理保护、养分供给通道和优化设计方法的固有困难，制备了长寿命的生物混合微机器人，本发明旨在通过仿生矿化的方法在生物材料表面原位构筑MOFs物理保护层，选择性透过生物材料存活必需的营养和气体，实现生物材料的生命维持。
本发明的优点：MOFs物理保护层可选择性透过生物材料存活必需的营养和气体，从而最大程度避免环境中的细胞毒性物质对细胞寿命的影响，有效延长心肌细胞的使用寿命。在同样的培养条件下培养7天后，带有MOFs壳层的心肌细胞的细胞密度明显高于心肌细胞。
本发明可获得一种MOFs包被心肌细胞核壳结构。
附图说明
图1为放大100倍的显微镜照片，图1中a和b为实施例一步骤六中 传代后不同方向上心肌细胞的显微镜照片，c和d为实施例一步骤八得到的MOFs包被心肌细胞核壳结构的显微镜照片；
图2为心肌细胞的显微镜照片，图2中a为HL-1小鼠心肌细胞培养7天后放大40倍的显微镜照片，b为实施例一步骤八得到的MOFs包被心肌细胞核壳结构培养7天后放大40倍的显微镜照片。
具体实施方式
以下实施例进一步说明本发明的内容，但不应理解为对本发明的限制。在不背离本发明实质的情况下，对本发明方法、步骤或条件所作的修改和替换，均属于本发明的范围。
具体实施方式一：本实施方式中一种MOFs包被心肌细胞核壳结构的制备方法，是按以下步骤完成的：
一、弃去HL-1小鼠心肌细胞培养基的上清液，使用PBS缓冲液或生理盐水对HL-1小鼠心肌细胞进行清洗；
二、将清洗后的HL-1小鼠心肌细胞加入到细胞培养瓶或细胞培养皿中，再加入质量分数为0.25％的胰酶PBS溶液，使质量分数为0.25％的胰酶PBS溶液覆盖在HL-1小鼠心肌细胞上面；
三、将步骤二中的细胞培养瓶或细胞培养皿放入温度为37℃的CO 2培养箱中消化，再加入培养基终止消化，得到细胞悬液；
四、将所述细胞悬液进行离心，弃上清液，得到细胞沉淀；
五、使用新鲜培养基对所述细胞沉淀进行重悬，再加入到细胞培养瓶或细胞培养皿中，将细胞培养瓶或细胞培养皿放入温度为37℃的CO 2培养箱中培养1天～7天，得到悬浮细胞；
六、步骤五得到悬浮细胞进行离心，收集细胞沉淀；使用新鲜培养基对所述细胞沉淀进行重悬，再转移到新的细胞培养瓶或细胞培养皿中传代，传代比例为1:(2～8)；
七、配制Zn(NO 3) 2·6H 2O水溶液和2-甲基咪唑水溶液；
步骤七中所述的Zn(NO 3) 2·6H 2O水溶液的浓度为1～10g/L；
步骤七中所述的2-甲基咪唑水溶液的浓度为5～20g/L；
八、向步骤六中得到的细胞培养瓶或细胞培养皿中分别加入所述Zn(NO 3) 2·6H 2O水溶液和2-甲基咪唑水溶液，再将细胞培养瓶或细胞培养 皿转移到温度为37℃的CO 2培养箱中培养1天～7天，得到MOFs包被心肌细胞核壳结构。
本实施方式步骤一中所述的HL-1小鼠心肌细胞培养基购买自湖南丰晖生物科技有限公司。
具体实施方式二：本实施方式与具体实施方式一不同点是：步骤一中所述的清洗次数为1次～2次。其它步骤与具体实施方式一相同。
具体实施方式三：本实施方式与具体实施方式一或二之一不同点是：步骤三中所述的CO 2培养箱中CO 2的体积分数为5％；步骤三中所述的培养基按质量分数组成为：90％DMEM高糖、9％胎牛血清和1％双抗；所述的双抗的浓度为100U/mL。其它步骤与具体实施方式一或二相同。
具体实施方式四：本实施方式与具体实施方式一至三之一不同点是：步骤三中所述的培养基与细胞培养瓶或细胞培养皿中HL-1小鼠心肌细胞的体积比为(6～8):1。其它步骤与具体实施方式一至三相同。
具体实施方式五：本实施方式与具体实施方式一至四之一不同点是：步骤三中所述的消化时间为0.5min～2min。其它步骤与具体实施方式一至四相同。
具体实施方式六：本实施方式与具体实施方式一至五之一不同点是：步骤四中所述的离心的速度为500r/min～2000r/min，离心的时间为3min～6min。其它步骤与具体实施方式一至五相同。
具体实施方式七：本实施方式与具体实施方式一至六之一不同点是：步骤五中所述的CO 2培养箱中CO 2的体积分数为5％；步骤五中所述的培养基按质量分数组成为：90％DMEM高糖、9％胎牛血清和1％双抗；所述的双抗的浓度为100U/mL。其它步骤与具体实施方式一至六相同。
具体实施方式八：本实施方式与具体实施方式一至七之一不同点是：步骤六中所述的培养基按质量分数组成为：90％DMEM高糖、9％胎牛血清和1％双抗组成；所述的双抗的浓度为100U/mL；步骤六中所述的离心的速度为500r/min～2000r/min，离心的时间为3min～6min。其它步骤与具体实施方式一至七相同。
具体实施方式九：本实施方式与具体实施方式一至八之一不同点是：步骤八中所述的CO 2培养箱中CO 2的体积分数为5％；步骤八中所述的 Zn(NO 3) 2·6H 2O水溶液与细胞培养基的体积比为6.25×10 -5～1.67×10 -3。其它步骤与具体实施方式一至八相同。
具体实施方式十：本实施方式与具体实施方式一至九之一不同点是：步骤八中所述的2-甲基咪唑水溶液与细胞培养基的体积比为6.25×10 -5～1.67×10 -3。其它步骤与具体实施方式一至九相同。
下面结合附图和实施例对本发明进行详细的说明。
实施例一：一种MOFs包被心肌细胞核壳结构的制备方法，是按以下步骤完成的：
一、弃去HL-1小鼠心肌细胞培养基的上清液，使用PBS缓冲液对HL-1小鼠心肌细胞进行清洗1次；
步骤一中所述的HL-1小鼠心肌细胞培养基购买自湖南丰晖生物科技有限公司；
二、将1mL清洗后的HL-1小鼠心肌细胞加入到T25细胞培养瓶中，再加入1mL质量分数为0.25％的胰酶PBS溶液，使质量分数为0.25％的胰酶PBS溶液覆盖在HL-1小鼠心肌细胞上面；
三、将步骤二中的细胞培养瓶放入温度为37℃的CO 2培养箱中消化0.5min，再加入6mL培养基终止消化，得到细胞悬液；
步骤三中所述的CO 2培养箱中CO 2的体积分数为5％；
步骤三中所述的培养基按质量分数组成为：90％DMEM高糖、9％胎牛血清和1％双抗；所述的双抗的浓度为100U/mL；
四、将细胞悬液进行离心，弃上清液，得到细胞沉淀；
步骤四中所述的离心的速度为1000r/min，离心的时间为4min；
五、使用6mL新鲜培养基对细胞沉淀进行重悬，再加到T25细胞培养瓶中，将细胞培养瓶放入温度为37℃的CO 2培养箱中培养2天；
步骤五中所述的CO 2培养箱中CO 2的体积分数为5％；
步骤五中所述的新鲜培养基按质量分数组成为：90％DMEM高糖、9％胎牛血清和1％双抗；所述的双抗的浓度为100U/mL；
六、步骤五得到悬浮细胞进行离心，收集细胞沉淀；使用1mL新鲜培养基对细胞沉淀进行重悬，再转移到新的T25细胞培养瓶中传代，传代比例为1:2；
步骤六中所述的新鲜培养基按质量分数组成为：90％DMEM高糖、9％胎牛血清和1％双抗；所述的双抗的浓度为100U/mL；
步骤六中所述的离心的速度为1000r/min，离心的时间为4min；
七、配制Zn(NO 3) 2·6H 2O水溶液和2-甲基咪唑水溶液；
步骤七中所述的Zn(NO 3) 2·6H 2O水溶液的浓度为5g/L；
步骤七中所述的2-甲基咪唑水溶液的浓度为10g/L；
八、向步骤六中得到的细胞培养瓶中分别加入1μL Zn(NO 3) 2·6H 2O水溶液和1μL 2-甲基咪唑水溶液，再将细胞培养瓶转移到温度为37℃的CO 2培养箱中培养2天，得到MOFs包被心肌细胞核壳结构；
步骤八中所述的CO 2培养箱中CO 2的体积分数为5％。
实施例二：一种MOFs包被心肌细胞核壳结构的制备方法，是按以下步骤完成的：
一、弃去HL-1小鼠心肌细胞培养基的上清液，使用PBS缓冲液对HL-1小鼠心肌细胞进行清洗1次；
步骤一中所述的HL-1小鼠心肌细胞培养基购买自湖南丰晖生物科技有限公司；
二、将1mL清洗后的HL-1小鼠心肌细胞加入到T25细胞培养瓶中，再加入0.5mL质量分数为0.25％的胰酶PBS溶液，使质量分数为0.25％的胰酶PBS溶液覆盖在HL-1小鼠心肌细胞上面；
三、将步骤二中的细胞培养瓶放入温度为37℃的CO 2培养箱中消化1min，再加入6mL培养基终止消化，得到细胞悬液；
步骤三中所述的CO 2培养箱中CO 2的体积分数为5％；
步骤三中所述的培养基按质量分数组成为：90％DMEM高糖、9％胎牛血清和1％双抗；所述的双抗的浓度为100U/mL；
四、将细胞悬液进行离心，弃上清液，得到细胞沉淀；
步骤四中所述的离心的速度为2000r/min，离心的时间为4min；
五、使用8mL新鲜培养基对细胞沉淀进行重悬，再加到T25细胞培养瓶中，将细胞培养瓶放入温度为37℃的CO 2培养箱中培养2天；
步骤五中所述的CO 2培养箱中CO 2的体积分数为5％；
步骤五中所述的新鲜培养基按质量分数组成为：90％DMEM高糖、 9％胎牛血清和1％双抗；所述的双抗的浓度为100U/mL；
六、步骤五得到悬浮细胞进行离心，收集细胞沉淀；使用1mL新鲜培养基对细胞沉淀进行重悬，再转移到新的T25细胞培养瓶中传代，传代比例为1:4；
步骤六中所述的新鲜培养基按质量分数组成为：90％DMEM高糖、9％胎牛血清和1％双抗；所述的双抗的浓度为100U/mL；
步骤六中所述的离心的速度为2000r/min，离心的时间为4min；
七、配制Zn(NO 3) 2·6H 2O水溶液和2-甲基咪唑水溶液；
步骤七中所述的Zn(NO 3) 2·6H 2O水溶液的浓度为10g/L；
步骤七中所述的2-甲基咪唑水溶液的浓度为20g/L；
八、向步骤六中得到的细胞培养瓶中分别加入5μL Zn(NO 3) 2·6H 2O水溶液和5μL 2-甲基咪唑水溶液，再将细胞培养瓶转移到温度为37℃的CO 2培养箱中培养2天，得到MOFs包被心肌细胞核壳结构；
步骤八中所述的CO 2培养箱中CO 2的体积分数为5％。
图1为放大100倍的显微镜照片，图中a和b为实施例一步骤六中传代后不同方向上心肌细胞的显微镜照片，c和d为实施例一步骤八得到的MOFs包被心肌细胞核壳结构的显微镜照片；
从图1可知，通过心肌细胞的体外培养(图a和b)，发现心肌细胞的厚度随着培养过程的进行而降低，而其铺展面积逐渐增大，并且心肌细胞的两端会与周围心肌细胞发生膜电位传导。可见心肌细胞在体外培养基环境中，也可以完整的周期性收缩运动。图c和d为心肌细胞与MOFs前驱体(金属离子和配体)共培养2天后，心肌细胞的显微镜照片。与图a和图b相比，图d明显多了许多晶体颗粒。由于MOFs前驱体溶液是溶于水的，说明在心肌细胞的培养条件下，MOFs前驱体可在心肌细胞膜表面形成MOFs颗粒，且不影响细胞的形态和生物活性。这一研究说明，MOFs颗粒的矿化合成是可行的。
图2为心肌细胞的显微镜照片，图中a为HL-1小鼠心肌细胞培养7天后放大40倍的显微镜照片，b为实施例一步骤八得到的MOFs包被心肌细胞核壳结构放大40倍的显微镜照片。
由图2可知，由同一批细胞传代得到的心肌细胞，分别培养7天后， MOFs包被心肌细胞的细胞密度明显高于未包被MOFs的心肌细胞，说明MOFs壳层有利于心肌细胞的生长。在相同的培养时间内，能够最大限度地保证细胞的存活。
以上所述实施例仅表达了本申请的几种实施方式，其描述较为具体和详细，但并不能因此而理解为对发明专利范围的限制。应当指出的是，对于本领域的普通技术人员来说，在不脱离本申请构思的前提下，还可以做出若干变形和改进，这些都属于本申请的保护范围。因此，本申请专利的保护范围应以所附权利要求为准。

Claims (16)

  1. 一种MOFs包被心肌细胞核壳结构的制备方法，其特征在于，是按以下步骤完成的：
    将Zn(NO 3) 2·6H 2O水溶液和2-甲基咪唑水溶液加入到传代培养的HL-1小鼠心肌细胞中，在温度为37℃的CO 2培养箱中培养1天～7天，得到MOFs包被心肌细胞核壳结构；
    所述传代比例为1:(2～8)；
    所述Zn(NO 3) 2·6H 2O水溶液的浓度为1～10g/L；
    所述2-甲基咪唑水溶液的浓度为5～20g/L。
  2. 一种MOFs包被心肌细胞核壳结构的制备方法，其特征在于，是按以下步骤完成的：
    一、弃去HL-1小鼠心肌细胞培养基的上清液，使用PBS缓冲液或生理盐水对HL-1小鼠心肌细胞进行清洗；
    二、将清洗后的HL-1小鼠心肌细胞加入到细胞培养瓶或细胞培养皿中，再加入质量分数为0.25％的胰酶PBS溶液，使质量分数为0.25％的胰酶PBS溶液覆盖在HL-1小鼠心肌细胞上面；
    三、将步骤二中的细胞培养瓶或细胞培养皿放入温度为37℃的CO 2培养箱中消化，再加入培养基终止消化，得到细胞悬液；
    四、将所述细胞悬液进行离心，弃上清液，得到细胞沉淀；
    五、使用新鲜培养基对所述细胞沉淀进行重悬，再加入到细胞培养瓶或细胞培养皿中，将所述细胞培养瓶或细胞培养皿放入温度为37℃的CO 2培养箱中培养1天～7天，得到悬浮细胞；
    六、步骤五得到悬浮细胞进行离心，收集细胞沉淀；使用新鲜培养基对所述细胞沉淀进行重悬，再转移到新的细胞培养瓶或细胞培养皿中传代，传代比例为1:(2～8)；
    七、配制Zn(NO 3) 2·6H 2O水溶液和2-甲基咪唑水溶液；
    所述的Zn(NO 3) 2·6H 2O水溶液的浓度为1～10g/L；
    所述的2-甲基咪唑水溶液的浓度为5～20g/L；
    八、向步骤六中得到的细胞培养瓶或细胞培养皿中分别加入所述Zn(NO 3) 2·6H 2O水溶液和2-甲基咪唑水溶液，再将细胞培养瓶或细胞培养 皿转移到温度为37℃的CO 2培养箱中培养1天～7天，得到MOFs包被心肌细胞核壳结构。
  3. 根据权利要求2所述的一种MOFs包被心肌细胞核壳结构的制备方法，其特征在于步骤一中所述的清洗次数为1次～2次。
  4. 根据权利要求2所述的一种MOFs包被心肌细胞核壳结构的制备方法，其特征在于步骤三中所述的CO 2培养箱中CO 2的体积分数为5％。
  5. 根据权利要求2或4所述的一种MOFs包被心肌细胞核壳结构的制备方法，其特征在于步骤三中所述的培养基按质量分数组成为：90％DMEM高糖、9％胎牛血清和1％双抗；所述的双抗的浓度为100U/mL。
  6. 根据权利要求2所述的一种MOFs包被心肌细胞核壳结构的制备方法，其特征在于步骤三中所述的培养基与细胞培养瓶或细胞培养皿中HL-1小鼠心肌细胞的体积比为(6～8):1。
  7. 根据权利要求2所述的一种MOFs包被心肌细胞核壳结构的制备方法，其特征在于步骤三中所述的消化时间为0.5min～2min。
  8. 根据权利要求2所述的一种MOFs包被心肌细胞核壳结构的制备方法，其特征在于步骤四中所述的离心的速度为500r/min～2000r/min，离心的时间为3min～6min。
  9. 根据权利要求2所述的一种MOFs包被心肌细胞核壳结构的制备方法，其特征在于步骤五中所述的CO 2培养箱中CO 2的体积分数为5％。
  10. 根据权利要求2或9所述的一种MOFs包被心肌细胞核壳结构的制备方法，其特征在于步骤五中所述的新鲜培养基按质量分数组成为：90％DMEM高糖、9％胎牛血清和1％双抗；所述的双抗的浓度为100U/mL。
  11. 根据权利要求2所述的一种MOFs包被心肌细胞核壳结构的制备方法，其特征在于步骤六中所述的新鲜培养基按质量分数组成为：90％DMEM高糖、9％胎牛血清和1％双抗组成；所述的双抗的浓度为100U/mL。
  12. 根据权利要求2或11所述的一种MOFs包被心肌细胞核壳结构的制备方法，其特征在于步骤六中所述的离心的速度为500r/min～2000r/min，离心的时间为3min～6min。
  13. 根据权利要求2所述的一种MOFs包被心肌细胞核壳结构的制备 方法，其特征在于步骤八中所述的CO 2培养箱中CO 2的体积分数为5％；步骤八中所述的Zn(NO 3) 2·6H 2O水溶液与细胞培养基的体积比为6.25×10 -5～1.67×10 -3。
  14. 根据权利要求2所述的一种MOFs包被心肌细胞核壳结构的制备方法，其特征在于步骤八中所述的2-甲基咪唑水溶液与细胞培养基的体积比为6.25×10 -5～1.67×10 -3。
  15. 权利要求1～14任意一项所述制备方法制备得到的MOFs包被心肌细胞核壳结构，由心肌细胞和包被所述心肌细胞的MOFs物理保护层组成。
  16. 权利要求15所述的MOFs包被心肌细胞核壳结构在制备生物混合微机器人中的应用。
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