Multi-metal ion coordinated hollow polydopamine nano material, synthetic method and application

Abstract

The invention belongs to the field of nano material preparation, and particularly relates to a multi-metal ion coordinated hollow polydopamine nano material, a synthesis method and application. The invention relates to a poly-dopamine composite material, which is poly-dopamine coordinated by Co / Fe / Ni-Zn multi-metal ions and has a hollow structure, and the particle size of the poly-dopamine coordinated by the Fe-Zn multi-metal ions is 238-272 nm; the particle size of the Co-Zn multi-metal ion coordinated polydopamine ranges from 45 nm to 56 nm; and the thickness of the poly-dopamine coordinated with Ni-Zn multi-metal ions is 58 to 70 nm. The hollow polydopamine nano-material with controllable size and multi-metal ion coordination is formed through an etching template method, the hollow polydopamine nano-material is different from a single polydopamine structure, and the prepared composite material is good in crystallinity and uniform and stable in dispersion, has higher nano-enzyme catalytic activity and can be applied to solar cells, solar cells, solar cells, solar cells, solar cells, solar cells, solar cells, solar cells, solar cells, solar cells and solar cells. Good application prospects are realized in the aspects of photo-thermal imaging and treatment of organisms and drug loading.

Description

Technical Field

[0001] The invention belongs to the field of nano material preparation, and more specifically, relates to a hollow polydopamine nano material coordinated by multiple metal ions, a synthesis method and an application thereof. Background Art

[0002] Polydopamine (PDA) is a polymer compound synthesized from dopamine molecules through oxidative polymerization. It has stable chemical properties and rich functional groups, such as hydroxyl, phenolic, aldehyde, etc. Nanozymes are a type of mimetic enzymes that have both the unique properties of nanomaterials and catalytic functions. They have the characteristics of high catalytic efficiency, stability, economy and large-scale preparation. They are widely used in medicine, chemical industry, food, agriculture and environment. Although there are many methods for the synthesis of PDA nanozymes, the catalytic activity of the synthesized PDA nanozymes is not high, and practical application is relatively difficult. Summary of the invention

[0003] In view of the above defects or improvement needs of the prior art, the object of the present invention is to provide a hollow polydopamine nanomaterial coordinated by multiple metal ions, a synthesis method and an application.

[0004] In order to achieve the above-mentioned invention object, the technical solution adopted by the present invention is:

[0005] The invention provides a hollow polydopamine nanomaterial coordinated by multiple metal ions, which is polydopamine coordinated by Co / Fe / Ni-Zn multiple metal ions and has a hollow structure. The particle size of the polydopamine coordinated by Fe-Zn multiple metal ions is 238-272nm; the particle size of the polydopamine coordinated by Co-Zn multiple metal ions is 45-56nm; and the particle size of the polydopamine coordinated by Ni-Zn multiple metal ions is 58-70nm.

[0006] The present invention also provides a method for synthesizing a hollow polydopamine nanomaterial coordinated by multiple metal ions, comprising the following steps:

[0007] (1) dissolving zinc nitrate and nickel nitrate / cobalt nitrate / ferric chloride in methanol to obtain solution A;

[0008] (2) dissolving dimethylimidazole in methanol solution to obtain solution B;

[0009] (3) at room temperature, solution A is quickly poured into the rapidly stirred solution B and stirred to form a Co / Fe / Ni-Zn multi-metal ion doped ZIF-8 structure;

[0010] (4) dissolving dopamine in methanol, adding ZIF-8 doped with multiple metal ions into the dopamine methanol solution, stirring, heating, condensing and refluxing, and forming a hollow polydopamine nanomaterial coordinated with multiple metal ions.

[0011] In the above scheme, the molar ratio of the nickel nitrate / cobalt nitrate / ferric chloride:zinc nitrate is 1:5-30.

[0012] In the above scheme, the concentration of zinc nitrate in the solution A is 10mM to 50mM.

[0013] In the above scheme, the concentration of dimethylimidazole in the solution B is 240mM to 360mM.

[0014] In the above scheme, the concentration of dopamine is 20mM to 60mM.

[0015] In the above scheme, the stirring time of step (2) is 0.5 to 3 hours.

[0016] In the above scheme, the stirring reaction time in step (4) is 10 to 15 hours.

[0017] In the above scheme, the heating condensation reflux temperature is 50-70°C.

[0018] The present invention also provides the use of hollow polydopamine nanomaterials coordinated by multiple metal ions as SOD and / or CAT enzymes.

[0019] The present invention also provides the use of hollow polydopamine nanomaterials coordinated by multiple metal ions in SOD and / or CAT enzyme catalysis reactions.

[0020] The present invention first prepares a Co / Fe / Ni-Zn multi-metal ion-doped ZIF-8 structure by an etching template method, then adds the structure to a dopamine methanol solution, stirs, heats, condenses and refluxes, and finally forms a hollow polydopamine structure coordinated by zinc and iron / cobalt / nickel multi-metal ions. The synthesized polydopamine nanoparticles coordinated by multi-metal ions can be stably dissolved in methanol and aqueous solutions and have lower toxicity. The size of the polydopamine can be accurately controlled by the size of the ZIF-8 template. After different multi-metal ions are coordinated with polydopamine, the activity of the nanoenzyme itself can be improved, including the activity of SOD and / or CAT enzymes. The method of the present invention is simple to operate, mild in reaction, and low in cost, and has good application prospects in solar cells, catalysis, photothermal imaging and treatment of organisms, and drug loading.

[0021] Beneficial effects of the present invention:

[0022] The hollow polydopamine nanomaterial coordinated by zinc and iron / cobalt / nickel multi-metal ions provided in the present application is different from a single polydopamine structure. Different multi-metal ions coordinated with polydopamine can significantly improve the activity of their own nanoenzymes, including SOD and / or CAT enzyme activity, etc.;

[0023] The method of the present invention is simple to operate, mild in reaction, and low in cost. The prepared composite material has good crystallinity, uniform and stable dispersion, and higher nanozyme catalytic activity. It has good application prospects in solar cells, catalysis, photothermal imaging and treatment of organisms, and drug loading. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a Zn / Co metal-doped organic framework ZIF-8 structure.

[0025] Figure 2 It is a polydopamine structure coordinated by Zn / Co metal ions.

[0026] Figure 3 Comparison of SOD enzyme activities of polydopamine coordinated with Zn / Co metal ions.

[0027] Figure 4 It is a Zn / Fe metal-doped organic framework ZIF-8 structure.

[0028] Figure 5 It is a polydopamine structure coordinated by Zn / Fe metal ions.

[0029] Figure 6 Comparison of CAT enzyme activities of polydopamine coordinated with Zn / Fe metal ions.

[0030] Figure 7 It is a Zn / Ni metal doped organic framework ZIF-8 structure.

[0031] Figure 8 It is a polydopamine structure coordinated with Zn / Ni metal ions.

[0032] Fig. 9 Comparison of SOD enzyme activities of polydopamine coordinated with Zn / Ni metal ions. DETAILED DESCRIPTION

[0033] In order to better understand the present invention, the content of the present invention is further explained below in conjunction with the embodiments, but the content of the present invention is not limited to the following embodiments.

[0034] Example 1

[0035] Preparation process of hollow polydopamine nanomaterials coordinated by zinc ions and cobalt ions: Add 12mL, 300mM dimethylimidazole methanol solution to a 25mL round-bottom flask, add 3mL, 8mM cobalt nitrate and 40mM zinc nitrate methanol solution while stirring rapidly, stir and react for 30min, centrifuge and resuspend, then add to 2.5mL, 40mM dopamine methanol solution and mix evenly, heat in a 60°C water bath, condense and reflux for 12h, and centrifuge to collect hollow structure polydopamine nanozymes coordinated by zinc ions and cobalt ions. The transmission electron microscopy (TEM) spectrum of the zinc ion and cobalt ion doped ZIF-8 structure prepared in this example is shown in Figure 1 ,from Figure 1 It can be seen that the particle size of the nanomaterial is 52.2 nm; Figure 2 Polydopamine nanozymes coordinated to zinc and cobalt ions Figure 2 It can be seen that the nanomaterial has a hollow structure and a particle size of 80.6 nm;

[0036] The SOD enzyme activity was detected using a superoxide dismutase detection kit. Specifically, the SOD enzyme activity of the nanozyme was detected by removing superoxide anions. The results were as follows: Figure 3 By comparing the SOD enzyme activity of polydopamine nanozymes coordinated by Zn / Co metal ions, it can be found that the addition of cobalt ions significantly enhanced the SOD enzyme activity of polydopamine. Compared with polydopamine HPDA, the SOD enzyme activity increased by about 6 times, and compared with Zn-HPDA, the SOD enzyme activity increased by about 2 times.

[0037] Example 2

[0038] Preparation process of polydopamine nanomaterial coordinated by zinc ions and iron ions: Add 120mL, 300mM dimethylimidazole methanol solution to a 250mL round-bottom flask, add 30mL, 6mM ferric chloride and 40mM zinc nitrate methanol solution while stirring rapidly, stir and react for 2h, centrifuge and resuspend, then add to 10mL, 40mM dopamine methanol solution and mix evenly, heat in a 60°C water bath, condense and reflux for 12h, and centrifuge to collect the hollow structure of zinc ions and iron ion coordinated polydopamine nanozymes. The transmission electron microscopy (TEM) spectrum of the zinc ion and iron ion doped ZIF-8 structure prepared in this example is shown in Figure 4 ,from Figure 4 It can be seen that the particle size of the nanomaterial is 258.1 nm; Figure 5 Polydopamine nanozymes that coordinate zinc and iron ions Figure 5 It can be seen that the nanomaterial has a hollow structure and a particle size of 478.3 nm;

[0039] The CAT enzyme activity was detected using a peroxidase enzyme detection kit. Figure 6By comparing the CAT enzyme activity of polydopamine coordinated by Zn / Fe metal ions, it can be found that the addition of iron ions significantly enhanced the CAT enzyme activity of polydopamine. Compared with polydopamine HPDA and Zn-HPDA, the CAT enzyme activity increased by about 4 times.

[0040] Example 3

[0041] Preparation process of polydopamine nanomaterial coordinated by zinc ions and nickel ions: Add 12mL, 300mM dimethylimidazole methanol solution to a 25mL round-bottom flask, add 3mL, 8mM nickel nitrate and 40mM zinc nitrate methanol solution while stirring rapidly, stir the reaction for 0.5h, centrifuge and resuspend, then add to 10mL, 40mM dopamine methanol solution and mix evenly, heat in a 60°C water bath, condense and reflux for 12h, and centrifuge to collect polydopamine nanozymes coordinated by zinc ions and nickel ions. The transmission electron microscopy (TEM) spectrum of the zinc ion and nickel ion doped ZIF-8 structure prepared in this example is shown in Figure 7 ,from Figure 7 It can be seen that the particle size of the nanomaterial is 63.5 nm; Figure 8 Polydopamine nanozymes coordinated to zinc and nickel ions Figure 8 It can be seen that the nanomaterial has a hollow structure and a particle size of 128.5 nm;

[0042] The SOD enzyme activity was detected using a superoxide dismutase detection kit. Specifically, the SOD enzyme activity of the nanozyme was detected by removing superoxide anions. The results were as follows: Fig. 9 By comparing the SOD enzyme activity of polydopamine coordinated by n / Ni metal ions, it can be found that the addition of iron ions significantly enhanced the SOD enzyme activity of polydopamine. Compared with polydopamine HPDA, the SOD enzyme activity increased by about 3 times, and compared with Zn-HPDA, the SOD enzyme activity increased by 1 times.

[0043] Zn-HPDA: Add 40 mL of 25 mM dimethylimidazole methanol solution to a 100 mL round-bottom flask, add 40 mL of 25 mM zinc nitrate methanol solution while stirring rapidly, stir for 4 hours, centrifuge and resuspend, then add to 10 mL of 5 mM dopamine methanol solution and mix evenly, condense and reflux in a 60°C water bath for 12 hours, and collect polydopamine containing zinc ions by centrifugation.

[0044] HPDA: 0.2g dopamine (PDA) was dissolved in 100mL Tris-HCL buffer (pH 8.5, 10mM) to prepare a dopamine solution (2mg / mL). 0.1g polystyrene powder (PS) was dispersed in the dopamine solution by ultrasound and stirred magnetically for 24h at room temperature. Then, a PS / PDA composite nanosphere core-shell structure was formed. These nanospheres were centrifuged at 10000rpm for 15min at room temperature, washed with ethanol several times, and then dried in a vacuum oven at room temperature for 24 hours. Finally, PS / PDA powder was added to chloroform and stirred for 6h to remove the PS template to form a hollow PDA nanosphere (HPDA). Centrifuged at 10000rpm for 15 minutes at room temperature, and HPDA was collected by washing with ethanol several times.

Claims

1. Hollow polydopamine nanomaterial coordinated by multiple metal ions, characterized in that: It is polydopamine coordinated by Co / Fe / Ni-Zn multi-metal ions and has a hollow structure. The particle size of the polydopamine coordinated by Fe-Zn multi-metal ions is 238-272nm; the particle size of the polydopamine coordinated by Co-Zn multi-metal ions is 45-56nm; and the particle size of the polydopamine coordinated by Ni-Zn multi-metal ions is 58-70nm.

2. The method for synthesizing the hollow polydopamine nanomaterial coordinated by multiple metal ions according to claim 1, characterized in that: The following steps are involved: (1) dissolving zinc nitrate and nickel nitrate / cobalt nitrate / ferric chloride in methanol to obtain solution A; (2) dissolving dimethylimidazole in methanol solution to obtain solution B; (3) at room temperature, solution A is quickly poured into the rapidly stirred solution B and stirred to form a Co / Fe / Ni-Zn multi-metal ion doped ZIF-8 structure; (4) dissolving dopamine in methanol, adding ZIF-8 doped with multiple metal ions into the dopamine methanol solution, stirring, heating, condensing and refluxing, and forming a hollow polydopamine nanomaterial coordinated with multiple metal ions.

3. The synthesis method according to claim 2, characterized in that: The molar ratio of the nickel nitrate / cobalt nitrate / ferric chloride:zinc nitrate is 1:5-30.

4. The synthesis method according to claim 2, characterized in that: The concentration of zinc nitrate in the solution A is 10 mM to 50 mM; the concentration of dimethylimidazole in the solution B is 240 mM to 360 mM.

5. The synthesis method according to claim 2, characterized in that: The concentration of dopamine is 20 mM to 60 mM.

6. The synthesis method according to claim 2, characterized in that: The stirring time in step (2) is 0.5 to 3 hours.

7. The synthesis method according to claim 2, characterized in that: The stirring reaction time of step (4) is 10 to 15 hours.

8. The synthesis method according to claim 2, characterized in that: The heating condensation reflux temperature is 50-70°C.

9. Use of the hollow polydopamine nanomaterial coordinated by multiple metal ions according to claim 1 as SOD and / or CAT enzymes.

10. Use of the hollow polydopamine nanomaterial coordinated by multiple metal ions according to claim 1 in SOD and / or CAT enzyme catalysis reactions.

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