A mitochondrion-imitated implantable magnesium-oxygen bio-battery and a preparation method thereof

Abstract

The application discloses a kind of mitochondrial implantable magnesium-oxygen bio-battery and preparation method thereof, belong to in-vivo energy device technical field.It includes the following steps: preparation inner membrane modified battery negative electrode;Preparation outer membrane modified battery positive electrode;Preparation electrolyte precursor solution;Preparation magnesium-oxygen bio-battery: inner membrane modified battery negative electrode is immersed in electrolyte precursor solution, take out and dry, make electrolyte precursor solution in-situ gelation on inner membrane modified battery negative electrode;Outer membrane modified battery positive electrode is wrapped in battery negative electrode-inner membrane-electrolyte outside treated by above steps, obtain mitochondrial implantable magnesium-oxygen bio-battery.Compared with prior art, the advantages of the present application are that: the double-layer membrane structure design of the present application is adopted, which can not only effectively prevent the corrosion of magnesium negative electrode, but also resist biological pollution, ensure the continuous transmission of oxygen, further improve the energy density, and reduce the foreign body reaction.

Description

Technical Field

[0001] This invention relates to the field of in vivo energy device technology, and more specifically, to a mitochondrial-inspired implantable magnesium-oxygen bio-battery and its preparation method. Background Technology

[0002] Over the past decade, implantable bioelectronic devices such as pacemakers, implantable biosensors, intelligent drug delivery systems, and artificial organs for disease treatment, physiological monitoring, and human enhancement have experienced rapid development. Simultaneously, developing in vivo energy devices that match the size of these devices is crucial; ideal in vivo energy devices should simultaneously possess high energy density, safety, and small size. The primary power source for implantable electronic devices is lithium-ion batteries, such as lithium-iodine batteries and lithium-carbon fluoride batteries. However, the low energy density and large size of these batteries hinder the miniaturization of implantable electronic devices. Furthermore, the presence of toxic substances in the electrodes and electrolytes necessitates stringent packaging, further increasing battery size and posing safety risks during implantation. Therefore, attention has been paid to other implantable batteries, such as primary batteries, sodium-ion batteries, and supercapacitors. However, the energy density of these batteries remains far below the requirements for practical applications.

[0003] Magnesium-oxygen bio-batteries are aqueous batteries with high theoretical energy density, capable of generating electricity from oxygen in bodily fluids. Although numerous studies have attempted to develop magnesium-oxygen bio-batteries and successfully achieved in vitro discharge in simulated bodily fluid environments (such as phosphate-buffered saline solutions), in vivo application remains challenging. On one hand, bodily fluids contain a large number of cells and proteins, which readily adsorb and adhere to the implanted bio-battery surface, forming a biofouling layer that hinders oxygen transport; the reactive magnesium anode is also easily corroded by water in the bodily fluids, leading to significant capacity loss. These factors result in a significant reduction in the performance of the bio-battery after implantation. On the other hand, implanting magnesium-oxygen bio-batteries into a living organism may trigger foreign body reactions, and the exchange of substances between the battery and the organism during discharge may also raise safety concerns.

[0004] In related technologies, such as patent document CN110099716B, an implantable medical device comprising a battery cell is disclosed. The battery cell includes: an anode; a cathode containing fluorinated carbon particles; a spacer between the anode and cathode; and an electrolyte in contact with the anode, cathode, and spacer. More than 50% by volume of the fluorinated carbon particles have a particle size ranging from 2 micrometers to 10 micrometers, and more than 50% by quantity of the fluorinated carbon particles have an aspect ratio of 1:1.2 to 1:8. However, this solution does not provide any technical guidance on how to achieve high energy density and good biocompatibility of batteries in vivo, a problem present in related technologies.

[0005] In summary, how to develop implantable batteries with high energy density and good biocompatibility is a problem that needs to be solved by existing technologies. Summary of the Invention

[0006] 1. Technical problems to be solved To address the challenge of developing implantable batteries with high energy density and good biocompatibility in existing technologies, this invention provides a mitochondrial-inspired implantable magnesium-oxygen bio-battery and its preparation method. This not only effectively prevents corrosion of the magnesium anode but also resists biocontamination, ensuring continuous oxygen transport and further improving energy density. Simultaneously, it reduces foreign body reactions, opening up a new direction for the development of high-performance implantable energy devices in biomedical applications.

[0007] 2. Technical Solution The objective of this invention is achieved through the following technical solutions.

[0008] A method for preparing a mitochondrial-inspired implantable magnesium-oxygen bio-battery, comprising the following steps: Preparation of inner membrane modified battery anode; Preparation of a battery cathode with an outer film modification; Preparation of electrolyte precursor solution; Preparation of magnesium-oxygen bio-batteries: The inner membrane modified battery negative electrode is immersed in an electrolyte precursor solution, removed and dried, so that the electrolyte precursor solution is gelled in situ on the inner membrane modified battery negative electrode; the outer membrane modified battery positive electrode is wrapped around the treated battery negative electrode-inner membrane-electrolyte to obtain a mitochondrial-inspired implantable magnesium-oxygen bio-battery.

[0009] Furthermore, the specific steps for preparing the inner film-modified battery anode are as follows: Mix 3 mL to 7 mL of acetone with 1 mL to 5 mL of methanol to obtain an acetone-methanol solvent. Add 0.5g~2g of polyvinyl acetate, 0.01g~0.05g of sodium chloride and 0.1g~1g of hydrophobic fumed silica nanoparticles to acetone-methanol solvent and stir for 30 min~90 min to obtain a viscous inner membrane precursor solution.

[0010] Furthermore, the polished magnesium wire is cleaned with anhydrous ethanol, then immersed in an inner membrane precursor solution to coat the electrode surface. The solution is then dried at 50℃~80℃ for 5min~20min to remove residual solvent and form a uniform inner membrane, thus obtaining an inner membrane modified battery negative electrode.

[0011] Furthermore, the specific steps for preparing the outer film-modified battery cathode are as follows: Dissolve 0.5g~1g of potassium chloride and 30mg~60mg of potassium chloroplatinate in 50mL~200mL of deionized water to obtain potassium chloride-potassium chloroplatinate precipitation solution; A carbon nanotube film was used as the working electrode, a platinum electrode as the counter electrode, and a silver-silver chloride electrode as the reference electrode. A voltage of 0.5V was applied to the working electrode. A constant potential step wave of 0.7V was applied for 10 seconds, and the cycle was repeated 50 to 400 times to obtain the positive electrode of a platinum-loaded carbon nanotube battery.

[0012] Furthermore, 0.05 g to 0.2 g of Tris-HCl was dissolved in 50 mL to 150 mL of deionized water, and a Tris-HCl buffer solution with a pH of 8 to 9 was prepared by adjusting the solution with concentrated hydrochloric acid. Dissolve 0.1g~0.5g of dopamine in 50mL~200mL of Tris-HCl buffer solution to obtain a Tris-HCl buffer solution containing dopamine. Platinum-loaded carbon nanotube battery cathode was immersed in a Tris-HCl buffer solution containing dopamine and shaken at room temperature for 18-30 hours to obtain polydopamine-modified platinum-loaded carbon nanotube battery cathode.

[0013] Furthermore, chloroform with a volume of 50 mL to 150 mL and ethanol with a volume of 0.5 mL to 2 mL are mixed to obtain a chloroform-ethanol solvent; Add 50 mg to 150 mg of phosphatidylethanolamine and 0.5 mg to 2 mg of sodium hydroxide to chloroform-ethanol solvent to obtain a phosphatidylethanolamine solution; The positive electrode of a platinum-loaded carbon nanotube battery modified with polydopamine was immersed in a phosphatidylethanolamine solution at room temperature and shaken for 36-60 hours, and then dried at room temperature to obtain the positive electrode of a platinum-loaded carbon nanotube battery modified with phosphatidylethanolamine.

[0014] Furthermore, 50 mg to 150 mg of phosphatidylcholine is dissolved in 50 mL to 150 mL of chloroform to obtain a phosphatidylcholine solution. A 50µL–200µL phosphatidylcholine solution was drop-coated onto the outer surface of the film, with an outer surface area of ​​0.25cm². 2 The carbon nanotube battery cathode with platinum loading and outer film modified was soaked in deionized water at room temperature for 36-60 hours and then dried at room temperature to obtain the cathode.

[0015] Furthermore, the specific steps for preparing the electrolyte precursor solution are as follows: Under conditions of 90°C to 100°C, 0.1 g to 1 g of polyvinyl alcohol is dissolved in 1 mL to 10 mL of deionized water to obtain a polyvinyl alcohol solution; Dissolve 0.05 g to 0.2 g of sodium gluconate in 0.5 mL to 1.5 mL of deionized water to obtain a sodium gluconate solution; Under continuous stirring, 0.5 mL to 2 mL of sodium gluconate solution was added to 2 mL to 10 mL of polyvinyl alcohol solution to obtain an electrolyte precursor solution.

[0016] Furthermore, the specific steps for preparing a magnesium-oxygen bio-battery are as follows: The inner membrane-modified battery negative electrode was immersed in an electrolyte precursor solution, and then dried at 50℃~80℃ for 20min~50min to allow the electrolyte precursor solution to gel in situ on the inner membrane-modified battery negative electrode. By wrapping the outer membrane-modified platinum-loaded carbon nanotube battery positive electrode around the treated battery negative electrode-inner membrane-electrolyte, a high-energy-density implantable magnesium-oxygen bio-battery mimicking mitochondria is obtained.

[0017] The mitochondrial-inspired implantable magnesium-oxygen bio-battery prepared according to the above-described method comprises an inner membrane-modified negative electrode, an electrolyte, and an outer membrane-modified positive electrode. The inner membrane-modified negative electrode, the electrolyte, and the outer membrane-modified positive electrode are arranged from the inside out, and are coaxially arranged.

[0018] 3. Beneficial effects Compared to existing technologies, the advantages of this invention are as follows: It employs a mitochondrial-inspired double-membrane structure design, with a magnesium wire as the negative electrode, a polyvinyl alcohol-sodium gluconate gel as the electrolyte, and a platinum-loaded carbon nanotube film as the positive electrode. The inner membrane is composed of a highly hydrophobic polymer, which significantly reduces water permeability and effectively prevents corrosion of the magnesium negative electrode. The outer membrane is composed of a phospholipid layer with zwitterionic groups, exhibiting good biocompatibility and high oxygen permeability, resisting biofouling and ensuring continuous oxygen transport. This double-membrane design further improves energy density while reducing foreign body reactions, ultimately enabling the magnesium-oxygen bio-battery to exhibit high performance and good biocompatibility after implantation. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of a mitochondrial-inspired implantable magnesium-oxygen bio-battery in one embodiment of the present invention; Figure 2 This is a schematic diagram of the inner and outer membranes of a mitochondrial-inspired implantable magnesium-oxygen bio-battery in one embodiment of the present invention. Figure 3 This is a schematic diagram of the operation of the double membrane of the mitochondrial-inspired implantable magnesium-oxygen bio-battery in one embodiment of the present invention. Figure 4 This is a statistical diagram of the energy density of a mitochondrial-inspired implantable magnesium-oxygen bio-battery during in vivo discharge, according to one embodiment of the present invention. Figure 5 This is a comparison diagram of the in vivo performance of a mitochondrial-inspired implantable magnesium-oxygen bio-battery in one embodiment of the present invention and implantable energy devices in related technologies. Figure 6 This is a statistical chart showing the expression levels of pro-inflammatory cytokines (interleukin-1β and interleukin-6) in serum after implantation of a mitochondrial-inspired implantable magnesium-oxygen bio-battery in one embodiment of the present invention. Figure 7 This is a statistical chart of serum biochemical indicators after the mitochondrial-inspired implantable magnesium-oxygen bio-battery was implanted in vivo in one embodiment of the present invention.

[0020] The labels in the diagram are as follows: 100, positive electrode of the battery with outer film modification; 200, electrolyte; 300, negative electrode of the battery with inner film modification. Detailed Implementation

[0021] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0022] Example 1 like Figure 1 As shown, this solution provides a mitochondrial-inspired implantable magnesium-oxygen bio-battery, including an inner membrane-modified negative electrode 300, an electrolyte 200, and an outer membrane-modified positive electrode 100. The inner membrane-modified negative electrode 300, electrolyte 200, and outer membrane-modified positive electrode 100 are arranged from the inside out, and are coaxially arranged. The mitochondrial-inspired double-membrane structure of the magnesium-oxygen battery enables high energy density and good biocompatibility.

[0023] The negative electrode of the battery is a magnesium wire; the electrolyte is a polyvinyl alcohol-sodium gluconate gel; and the positive electrode is a carbon nanotube film loaded with platinum.

[0024] like Figure 2 As shown, the inner membrane is composed of polyvinyl acetate, sodium chloride, and hydrophobic fumed silica nanoparticles; the outer membrane is composed of a phospholipid layer containing polydopamine, phosphatidylcholine, and phosphatidylethanolamine.

[0025] like Figure 3 As shown, the inner membrane is rich in hydrophobic substances (polyvinyl acetate and hydrophobic fumed silica nanoparticles), thus exhibiting high hydrophobicity and significantly reducing water penetration, thereby effectively inhibiting the corrosion of the magnesium anode. The outer membrane is a phospholipid layer with zwitterionic groups, which can resist biological contamination from body fluids, has high oxygen permeability, ensures continuous oxygen transport, and reduces foreign body reactions.

[0026] This embodiment discloses a method for preparing a mitochondrial-inspired implantable magnesium-oxygen bio-battery, including the following steps: Preparation of inner membrane modified battery anode: Mix 3 mL of acetone with 1 mL of methanol to obtain a homogeneous acetone-methanol solvent. Add 0.5 g of polyvinyl acetate, 0.01 g of sodium chloride and 0.1 g of hydrophobic fumed silica nanoparticles to acetone-methanol solvent and stir for 30 min to obtain a uniform viscous inner membrane precursor solution. Magnesium wire is polished, cleaned with anhydrous ethanol, and then immersed in an inner membrane precursor solution to uniformly coat the electrode surface. It is then dried at 50 °C for 5 min to remove residual solvent and form a uniform inner membrane, thus obtaining an inner membrane modified battery negative electrode.

[0027] Preparation of battery cathode with outer film modification: Dissolve 0.5g of potassium chloride and 30mg of potassium chloroplatinate in 50mL of deionized water to obtain a potassium chloride-potassium chloroplatinate precipitate. A carbon nanotube film was used as the working electrode, a platinum electrode as the counter electrode, and a silver-silver chloride electrode as the reference electrode. A voltage of 0.5 V was applied to the working electrode. A constant potential step wave of 0.7 V was applied for 10 s and 50 cycles to obtain the positive electrode of a carbon nanotube battery loaded with platinum. Dissolve 0.05 g Tris-HCl in 50 mL of deionized water and adjust the pH of the solution to 8 using concentrated hydrochloric acid; wherein Tris-HCl is tris(hydroxymethyl)aminomethane hydrochloride. 0.1 g of dopamine was dissolved in 50 mL of Tris-HCl buffer solution to obtain a Tris-HCl buffer solution containing dopamine. Platinum-loaded carbon nanotube battery cathode was immersed in a Tris-HCl buffer solution containing dopamine and shaken at room temperature for 18 h to obtain polydopamine-modified platinum-loaded carbon nanotube battery cathode.

[0028] Mix 50 mL of chloroform and 0.5 mL of ethanol to obtain a chloroform-ethanol solvent; Add 50 mg of phosphatidylethanolamine and 0.5 mg of sodium hydroxide to chloroform-ethanol solvent to obtain a phosphatidylethanolamine solution; The positive electrode of a platinum-loaded carbon nanotube battery modified with polydopamine was immersed in a phosphatidylethanolamine solution at room temperature and shaken for 36 hours to perform phosphatidylethanolamine grafting. After drying at room temperature, the positive electrode of a platinum-loaded carbon nanotube battery modified with phosphatidylethanolamine was obtained. Dissolve 50 mg of phosphatidylcholine in 50 mL of chloroform to obtain a phosphatidylcholine solution. A 50 µL solution of phosphatidylcholine was drop-coated onto the outer surface of the platinum-loaded carbon nanotube cathode modified with phosphatidylethanolamine, resulting in an outer surface area of ​​0.25 cm². 2 The phospholipid layer was soaked in deionized water at room temperature for 36 h to allow for self-assembly of the phospholipid layer. After drying at room temperature, a platinum-loaded carbon nanotube battery cathode with an outer film modified was obtained.

[0029] Preparation of electrolyte precursor solution: At 90°C, 0.1 g of polyvinyl alcohol was dissolved in 1 mL of deionized water to obtain a polyvinyl alcohol solution. Dissolve 0.05 g sodium gluconate in 0.5 mL of deionized water to obtain a sodium gluconate solution; Under continuous stirring, 0.5 mL of sodium gluconate solution was added to 2 mL of polyvinyl alcohol solution to obtain an electrolyte precursor solution. Preparation of magnesium-oxygen bio-batteries: The inner membrane-modified battery negative electrode was immersed in an electrolyte precursor solution, and then dried at 50 °C for 20 min to allow the electrolyte precursor solution to gel in situ on the inner membrane-modified battery negative electrode. By wrapping the outer membrane-modified platinum-loaded carbon nanotube battery positive electrode around the battery negative electrode-inner membrane-electrolyte treated in the above steps, a high-energy-density implantable magnesium-oxygen bio-battery mimicking mitochondria is obtained.

[0030] This invention discloses a mitochondrial-inspired implantable magnesium-oxygen bio-battery and its preparation method. The negative electrode is a magnesium wire; the electrolyte is polyvinyl alcohol-sodium gluconate gel; the positive electrode is a carbon nanotube-platinum film; the inner membrane is composed of a highly hydrophobic polymer: the highly hydrophobic polymer significantly reduces water permeability, thereby effectively preventing corrosion of the magnesium negative electrode; the outer membrane is composed of a phospholipid layer: the phospholipid layer with zwitterionic groups has good biocompatibility and high oxygen permeability, ensuring continuous oxygen transport while reducing foreign body reactions. This results in a magnesium-oxygen bio-battery exhibiting high performance and good biocompatibility after implantation.

[0031] Example 2 Based on the mitochondrial-inspired implantable magnesium-oxygen bio-battery of Example 1, this example discloses a method for preparing a high-energy-density implantable magnesium-oxygen bio-battery in the mitochondrial-inspired manner, including the following steps. Preparation of inner membrane modified battery anode: Mix 5 mL of acetone with 2 mL of methanol to obtain a homogeneous acetone-methanol solvent. 1 g of polyvinyl acetate, 0.02 g of sodium chloride and 0.3 g of hydrophobic fumed silica nanoparticles were added to an acetone-methanol solvent and stirred for 50 min to obtain a uniform viscous inner membrane precursor solution. Magnesium wire is polished, cleaned with anhydrous ethanol, and then immersed in an inner membrane precursor solution to uniformly coat the electrode surface. It is then dried at 60 °C for 10 min to remove residual solvent and form a uniform inner membrane, thus obtaining an inner membrane modified battery negative electrode.

[0032] Preparation of battery cathode with outer film modification: Dissolve 0.7g potassium chloride and 40mg potassium chloroplatinate in 100mL of deionized water to obtain potassium chloride-potassium chloroplatinate precipitate; A carbon nanotube film was used as the working electrode, a platinum electrode as the counter electrode, and a silver-silver chloride electrode as the reference electrode. A voltage of 0.5 V was applied to the working electrode. A constant potential step wave of 0.7 V was applied for 10 seconds and cyclicated 100 times to obtain the positive electrode of a carbon nanotube battery loaded with platinum. Dissolve 0.1 g Tris-HCl in 80 mL of deionized water and adjust the pH of the solution to 8.3 using concentrated hydrochloric acid. 0.2 g of dopamine was dissolved in 100 mL of Tris-HCl buffer solution to obtain a Tris-HCl buffer solution containing dopamine. Platinum-loaded carbon nanotube battery cathode was immersed in a Tris-HCl buffer solution containing dopamine and shaken at room temperature for 21 h to obtain polydopamine-modified platinum-loaded carbon nanotube battery cathode.

[0033] Mix 85 mL of chloroform and 1 mL of ethanol to obtain a chloroform-ethanol solvent; Add 90 mg of phosphatidylethanolamine and 1 mg of sodium hydroxide to a chloroform-ethanol solvent to obtain a phosphatidylethanolamine solution; The positive electrode of a platinum-loaded carbon nanotube battery modified with polydopamine was immersed in a phosphatidylethanolamine solution at room temperature and shaken for 45 h to perform phosphatidylethanolamine grafting. After drying at room temperature, the positive electrode of a platinum-loaded carbon nanotube battery modified with phosphatidylethanolamine was obtained. Dissolve 85 mg of phosphatidylcholine in 90 mL of chloroform to obtain a phosphatidylcholine solution; A 100 µL solution of phosphatidylcholine was drop-coated onto the outer surface of the platinum-loaded carbon nanotube cathode modified with phosphatidylethanolamine, resulting in an outer surface area of ​​0.25 cm². 2The phospholipid layer was soaked in deionized water at room temperature for 45 hours to allow for self-assembly of the phospholipid layer. After drying at room temperature, a platinum-loaded carbon nanotube battery cathode with an outer film modified was obtained.

[0034] Preparation of electrolyte precursor solution: At 93°C, 0.4 g of polyvinyl alcohol was dissolved in 3 mL of deionized water to obtain a polyvinyl alcohol solution. Dissolve 0.1 g of sodium gluconate in 0.8 mL of deionized water to obtain a sodium gluconate solution; Under continuous stirring, 1 mL of sodium gluconate solution was added to 5 mL of polyvinyl alcohol solution to obtain an electrolyte precursor solution. Preparation of magnesium-oxygen bio-batteries: The inner membrane-modified battery negative electrode was immersed in an electrolyte precursor solution and dried at 60 °C for 30 min to allow the electrolyte precursor solution to gel in situ on the inner membrane-modified battery negative electrode. By wrapping the outer membrane-modified platinum-loaded carbon nanotube battery positive electrode around the battery negative electrode-inner membrane-electrolyte treated in the above steps, a high-energy-density implantable magnesium-oxygen bio-battery mimicking mitochondria is obtained.

[0035] Example 3 Based on the mitochondrial-inspired implantable magnesium-oxygen bio-battery of Example 1, this example discloses a method for preparing a high-energy-density implantable magnesium-oxygen bio-battery in the mitochondrial-inspired manner, including the following steps. Preparation of inner membrane modified battery anode: Mix 6 mL of acetone with 4 mL of methanol to obtain a homogeneous acetone-methanol solvent. 1.5 g of polyvinyl acetate, 0.03 g of sodium chloride and 0.7 g of hydrophobic fumed silica nanoparticles were added to an acetone-methanol solvent and stirred for 70 min to obtain a uniform viscous inner membrane precursor solution. Magnesium wire is polished, cleaned with anhydrous ethanol, and then immersed in an inner membrane precursor solution to uniformly coat the electrode surface. It is then dried at 70 °C for 15 min to remove residual solvent and form a uniform inner membrane, thus obtaining an inner membrane modified battery negative electrode.

[0036] Preparation of battery cathode with outer film modification: Dissolve 0.9 g of potassium chloride and 50 mg of potassium chloroplatinate in 150 mL of deionized water to obtain a potassium chloride-potassium chloroplatinate precipitate. A carbon nanotube film was used as the working electrode, a platinum electrode as the counter electrode, and a silver-silver chloride electrode as the reference electrode. A voltage of 0.5 V was applied to the working electrode. A constant potential step wave of 0.7 V was applied for 10 s and 200 cycles to obtain the positive electrode of a carbon nanotube battery loaded with platinum. Dissolve 0.15 g Tris-HCl in 120 mL of deionized water and adjust the pH of the solution to 8.7 using concentrated hydrochloric acid. 0.3 g of dopamine was dissolved in 150 mL of Tris-HCl buffer solution to obtain a Tris-HCl buffer solution containing dopamine. Platinum-loaded carbon nanotube battery cathode was immersed in a Tris-HCl buffer solution containing dopamine and shaken at room temperature for 25 h to obtain polydopamine-modified platinum-loaded carbon nanotube battery cathode.

[0037] Mix 125 mL of chloroform and 1.5 mL of ethanol to obtain a chloroform-ethanol solvent; 120 mg of phosphatidylethanolamine and 1.5 mg of sodium hydroxide were added to a chloroform-ethanol solvent to obtain a phosphatidylethanolamine solution; The positive electrode of a platinum-loaded carbon nanotube battery modified with polydopamine was immersed in a phosphatidylethanolamine solution at room temperature and shaken for 55 h to perform phosphatidylethanolamine grafting. After drying at room temperature, the positive electrode of a platinum-loaded carbon nanotube battery modified with phosphatidylethanolamine was obtained. Dissolve 125 mg of phosphatidylcholine in 120 mL of chloroform to obtain a phosphatidylcholine solution; A 150 µL solution of phosphatidylcholine was drop-coated onto the outer surface of the platinum-loaded carbon nanotube cathode modified with phosphatidylethanolamine, resulting in an outer surface area of ​​0.25 cm². 2 The phospholipid layer was soaked in deionized water at room temperature for 55 hours to allow for self-assembly of the phospholipid layer. After drying at room temperature, a platinum-loaded carbon nanotube battery cathode with an outer film modified was obtained.

[0038] Preparation of electrolyte precursor solution: At 97°C, 0.7 g of polyvinyl alcohol was dissolved in 8 mL of deionized water to obtain a polyvinyl alcohol solution. Dissolve 0.15 g of sodium gluconate in 1.2 mL of deionized water to obtain a sodium gluconate solution; Under continuous stirring, 1.5 mL of sodium gluconate solution was added to 8 mL of polyvinyl alcohol solution to obtain an electrolyte precursor solution. Preparation of magnesium-oxygen bio-batteries: The inner membrane-modified battery negative electrode was immersed in an electrolyte precursor solution and dried at 70 °C for 40 min to allow the electrolyte precursor solution to gel in situ on the inner membrane-modified battery negative electrode. By wrapping the outer membrane-modified platinum-loaded carbon nanotube battery positive electrode around the battery negative electrode-inner membrane-electrolyte treated in the above steps, a high-energy-density implantable magnesium-oxygen bio-battery mimicking mitochondria is obtained.

[0039] Example 4 Based on the mitochondrial-inspired implantable magnesium-oxygen bio-battery of Example 1, this example discloses a method for preparing a high-energy-density implantable magnesium-oxygen bio-battery in the mitochondrial-inspired manner, including the following steps. Preparation of inner membrane modified battery anode: 7 mL of acetone and 5 mL of methanol were mixed to obtain a homogeneous acetone-methanol solvent. 2 g of polyvinyl acetate, 0.05 g of sodium chloride and 1 g of hydrophobic fumed silica nanoparticles were added to an acetone-methanol solvent and stirred for 90 min to obtain a uniform viscous inner membrane precursor solution. Magnesium wire is polished, cleaned with anhydrous ethanol, and then immersed in an inner membrane precursor solution to uniformly coat the electrode surface. It is then dried at 80°C for 20 min to remove residual solvent and form a uniform inner membrane, thus obtaining an inner membrane modified battery negative electrode.

[0040] Preparation of battery cathode with outer film modification: Dissolve 1g of potassium chloride and 60mg of potassium chloroplatinate in 200mL of deionized water to obtain a potassium chloride-potassium chloroplatinate precipitate. A carbon nanotube film was used as the working electrode, a platinum electrode as the counter electrode, and a silver-silver chloride electrode as the reference electrode. A voltage of 0.5 V was applied to the working electrode. A constant potential step wave of 0.7 V was applied for 10 s and cyclicated 400 times to obtain the positive electrode of a carbon nanotube battery loaded with platinum. Dissolve 0.2g Tris-HCl in 150mL of deionized water and adjust the pH of the solution to 9 using concentrated hydrochloric acid. Dissolve 0.5 g of dopamine in 200 mL of Tris-HCl buffer solution to obtain a Tris-HCl buffer solution containing dopamine. Platinum-loaded carbon nanotube battery cathode was immersed in a Tris-HCl buffer solution containing dopamine and shaken at room temperature for 30 h to obtain polydopamine-modified platinum-loaded carbon nanotube battery cathode.

[0041] Mix 150 mL of chloroform and 2 mL of ethanol to obtain a chloroform-ethanol solvent. 150 mg of phosphatidylethanolamine and 2 mg of sodium hydroxide were added to a chloroform-ethanol solvent to obtain a phosphatidylethanolamine solution; The positive electrode of a platinum-loaded carbon nanotube battery modified with polydopamine was immersed in a phosphatidylethanolamine solution at room temperature and shaken for 60 h to perform phosphatidylethanolamine grafting. After drying at room temperature, the positive electrode of a platinum-loaded carbon nanotube battery modified with phosphatidylethanolamine was obtained. Dissolve 150 mg of phosphatidylcholine in 150 mL of chloroform to obtain a phosphatidylcholine solution. A 200 µL solution of phosphatidylcholine was drop-coated onto the outer surface of the platinum-loaded carbon nanotube cathode modified with phosphatidylethanolamine, resulting in an outer surface area of ​​0.25 cm². 2 The phospholipid layer was soaked in deionized water at room temperature for 60 hours to allow for self-assembly of the phospholipid layer. After drying at room temperature, a platinum-loaded carbon nanotube battery cathode with an outer film modified was obtained.

[0042] Preparation of electrolyte precursor solution: At 100°C, 1 g of polyvinyl alcohol was dissolved in 10 mL of deionized water to obtain a polyvinyl alcohol solution. Dissolve 0.2 g sodium gluconate in 1.5 mL of deionized water to obtain a sodium gluconate solution; Under continuous stirring, 2 mL of sodium gluconate solution was added to 10 mL of polyvinyl alcohol solution to obtain an electrolyte precursor solution.

[0043] Preparation of magnesium-oxygen bio-batteries: The inner membrane-modified battery negative electrode was immersed in an electrolyte precursor solution and dried at 80 °C for 50 min to allow the electrolyte precursor solution to gel in situ on the inner membrane-modified battery negative electrode. By wrapping the outer membrane-modified platinum-loaded carbon nanotube battery positive electrode around the battery negative electrode-inner membrane-electrolyte treated in the above steps, a high-energy-density implantable magnesium-oxygen bio-battery mimicking mitochondria is obtained.

[0044] like Figure 4 As shown, the mitochondrial-inspired high-energy-density implantable magnesium-oxygen bio-battery exhibits extremely high energy density after implantation, with a maximum energy density of 2517 Wh·L. –1 Or 1491 Wh·kg –1 .

[0045] like Figure 5 As shown, compared with implantable energy devices in related technologies, the mitochondrial-inspired high-energy-density implantable magnesium-oxygen bio-battery has a maximum energy density of 2517 Wh·L⁻¹. –1 It is 2.5 times the highest performance reported in the literature to date.

[0046] like Figure 6As shown, the inflammatory response of the mitochondrial-inspired high-energy-density implantable magnesium-oxygen bio-battery with a double membrane was comparable to that of the control group within 1 to 7 days after implantation, indicating that the magnesium-oxygen bio-battery has good affinity with tissues and does not cause abnormal or chronic immune responses after implantation.

[0047] like Figure 7 As shown, within two months post-implantation, there were no significant differences in blood parameters between the magnesium-oxygen battery pack with the double-layer membrane and the control group, indicating that the battery has good biocompatibility and is safe for in vivo application. In contrast, some parameters of the magnesium-oxygen battery pack without the double-layer membrane showed abnormalities.

[0048] The double-layer membrane structure used in this design not only effectively protects the magnesium anode from corrosion, but also resists contamination from cells and proteins in body fluids, enhances the biocompatibility of the cathode in the biological environment, ensures continuous oxygen transport, and reduces foreign body reactions. This enables the mitochondrial-inspired implantable magnesium-oxygen bio-battery to achieve high energy density and good biocompatibility in vivo.

[0049] The invention and its embodiments have been described above illustratively. This description is not restrictive, and the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. The accompanying drawings are only one embodiment of the invention, and the actual structure is not limited thereto. No reference numerals in the claims should limit the scope of the claims. Therefore, if a person skilled in the art is inspired by this description and designs a similar structure and embodiment without departing from the spirit of the invention, such design should fall within the scope of protection of this patent. Furthermore, the word "comprising" does not exclude other elements or steps, and the word "a" preceding an element does not exclude the inclusion of "a plurality" of that element. Multiple elements stated in the product claims may also be implemented by a single element through software or hardware. The terms "first," "second," etc., are used to indicate names and do not indicate any specific order.

Claims

1. A method for preparing a mitochondrial-inspired implantable magnesium-oxygen bio-battery, characterized in that, Magnesium wire was used as the negative electrode, platinum-loaded carbon nanotube film was used as the positive electrode, and polyvinyl alcohol-sodium gluconate gel was used as the electrolyte. The specific steps are as follows: Preparation of inner membrane modified battery anode: Acetone and methanol are mixed to obtain acetone-methanol solvent; polyvinyl acetate, sodium chloride and hydrophobic fumed silica nanoparticles are added to acetone-methanol solvent and stirred to obtain viscous inner membrane precursor solution; magnesium wire is immersed in inner membrane precursor solution to coat the electrode surface with inner membrane precursor solution, and after drying, residual solvent is removed to form a uniform inner membrane, thus obtaining inner membrane modified battery anode; Preparation of the outer film modified battery cathode: Tris-HCl was dissolved in deionized water, and the Tris-HCl buffer solution was prepared by adjusting the solution with concentrated hydrochloric acid; dopamine was dissolved in the Tris-HCl buffer solution to obtain a dopamine-containing Tris-HCl buffer solution; the platinum-loaded carbon nanotube battery cathode was immersed in the dopamine-containing Tris-HCl buffer solution and shaken to obtain a polydopamine-modified platinum-loaded carbon nanotube battery cathode; Chloroform and ethanol were mixed to obtain a chloroform-ethanol solvent; phosphatidylethanolamine and sodium hydroxide were added to the chloroform-ethanol solvent to obtain a phosphatidylethanolamine solution; the polydopamine-modified platinum-loaded carbon nanotube battery cathode was immersed in the phosphatidylethanolamine solution, shaken, and dried to obtain a phosphatidylethanolamine-modified platinum-loaded carbon nanotube battery cathode. Phosphatidylcholine was dissolved in chloroform to obtain a phosphatidylcholine solution; the phosphatidylcholine solution was drop-coated onto the outer surface of the positive electrode of a phosphatidylethanolamine-modified platinum-loaded carbon nanotube battery, which was then soaked in deionized water and dried to obtain a platinum-loaded carbon nanotube battery positive electrode with an outer film modified; an electrolyte precursor solution was prepared. Preparation of magnesium-oxygen bio-batteries: The inner membrane modified battery negative electrode is immersed in an electrolyte precursor solution, removed and dried, so that the electrolyte precursor solution is gelled in situ on the inner membrane modified battery negative electrode; the outer membrane modified battery positive electrode is wrapped around the treated battery negative electrode-inner membrane-electrolyte to obtain a mitochondrial-inspired implantable magnesium-oxygen bio-battery.

2. The method for preparing the mitochondrial-inspired implantable magnesium-oxygen bio-battery according to claim 1, characterized in that, The specific steps for preparing the inner membrane modified battery negative electrode are as follows: Mix 3 mL to 7 mL of acetone with 1 mL to 5 mL of methanol to obtain an acetone-methanol solvent. Add 0.5g~2g of polyvinyl acetate, 0.01g~0.05g of sodium chloride and 0.1g~1g of hydrophobic fumed silica nanoparticles to acetone-methanol solvent and stir for 30min~90min to obtain a viscous inner membrane precursor solution.

3. The method for preparing the mitochondrial-inspired implantable magnesium-oxygen bio-battery according to claim 2, characterized in that, The polished magnesium wire was cleaned with anhydrous ethanol, then immersed in an inner membrane precursor solution to coat the electrode surface. The wire was then dried at 50℃~80℃ for 5min~20min to remove residual solvent and form a uniform inner membrane, thus obtaining an inner membrane modified battery negative electrode.

4. The method for preparing the mitochondrial-inspired implantable magnesium-oxygen bio-battery according to claim 1, characterized in that, The specific steps for preparing the outer film-modified battery cathode are as follows: Dissolve 0.5g~1g of potassium chloride and 30mg~60mg of potassium chloroplatinate in 50mL~200mL of deionized water to obtain potassium chloride-potassium chloroplatinate precipitation solution; Using a carbon nanotube film as the working electrode, a platinum electrode as the counter electrode, and a silver-silver chloride electrode as the reference electrode, constant potential step waves of 0.5V and -0.7V were applied to the working electrode for 10s each, and the cycle was repeated 50 to 400 times to obtain a platinum-loaded carbon nanotube battery cathode.

5. The method for preparing the mitochondrial-inspired implantable magnesium-oxygen bio-battery according to claim 4, characterized in that, Dissolve 0.05 g to 0.2 g of Tris-HCl in 50 mL to 150 mL of deionized water, and adjust the pH of the Tris-HCl buffer solution to 8 to 9 using concentrated hydrochloric acid. Dissolve 0.1g~0.5g of dopamine in 50mL~200mL of Tris-HCl buffer solution to obtain a Tris-HCl buffer solution containing dopamine. Platinum-loaded carbon nanotube battery cathode was immersed in a Tris-HCl buffer solution containing dopamine and shaken at room temperature for 18-30 hours to obtain polydopamine-modified platinum-loaded carbon nanotube battery cathode.

6. The method for preparing the mitochondrial-inspired implantable magnesium-oxygen bio-battery according to claim 5, characterized in that, Mix 50 mL to 150 mL of chloroform with 0.5 mL to 2 mL of ethanol to obtain a chloroform-ethanol solvent. Add 50 mg to 150 mg of phosphatidylethanolamine and 0.5 mg to 2 mg of sodium hydroxide to chloroform-ethanol solvent to obtain a phosphatidylethanolamine solution; The positive electrode of a platinum-loaded carbon nanotube battery modified with polydopamine was immersed in a phosphatidylethanolamine solution at room temperature and shaken for 36-60 hours, and then dried at room temperature to obtain the positive electrode of a platinum-loaded carbon nanotube battery modified with phosphatidylethanolamine.

7. The method for preparing the mitochondrial-inspired implantable magnesium-oxygen bio-battery according to claim 6, characterized in that, Dissolve 50 mg to 150 mg of phosphatidylcholine in 50 mL to 150 mL of chloroform to obtain a phosphatidylcholine solution. A 50µL–200µL solution of phosphatidylcholine was drop-coated onto the outer surface of the film, with an outer surface area of ​​0.25cm². 2 The carbon nanotube battery cathode with platinum loading and outer film modified was soaked in deionized water at room temperature for 36-60 hours and then dried at room temperature.

8. The method for preparing the mitochondrial-inspired implantable magnesium-oxygen bio-battery according to claim 1, characterized in that, The specific steps for preparing the electrolyte precursor solution are as follows: Under conditions of 90°C to 100°C, 0.1 g to 1 g of polyvinyl alcohol is dissolved in 1 mL to 10 mL of deionized water to obtain a polyvinyl alcohol solution; Dissolve 0.05 g to 0.2 g of sodium gluconate in 0.5 mL to 1.5 mL of deionized water to obtain a sodium gluconate solution; Under continuous stirring, 0.5 mL to 2 mL of sodium gluconate solution was added to 2 mL to 10 mL of polyvinyl alcohol solution to obtain an electrolyte precursor solution.

9. The method for preparing the mitochondrial-inspired implantable magnesium-oxygen bio-battery according to claim 1, characterized in that, The specific steps for preparing a magnesium-oxygen bio-battery are as follows: The inner membrane-modified battery negative electrode was immersed in an electrolyte precursor solution, and then dried at 50℃~80℃ for 20min~50min to allow the electrolyte precursor solution to gel in situ on the inner membrane-modified battery negative electrode. By wrapping the outer membrane-modified platinum-loaded carbon nanotube battery positive electrode around the treated battery negative electrode-inner membrane-electrolyte, a high-energy-density implantable magnesium-oxygen bio-battery mimicking mitochondria is obtained.

10. The mitochondrial-inspired implantable magnesium-oxygen bio-battery prepared by the method according to any one of claims 1-9, characterized in that, include, The battery comprises an inner-film modified negative electrode, an electrolyte, and an outer-film modified positive electrode, wherein the inner-film modified negative electrode, the electrolyte, and the outer-film modified positive electrode are arranged from the inside out, and the inner-film modified negative electrode, the electrolyte, and the outer-film modified positive electrode are coaxially arranged.

Images