KR101231565B1 - Preparation method of dna-carbon nanotube hydrogel fiber and dna-carbon nanotube hydrogel fiber thereof - Google Patents

Abstract

The present invention relates to a method for preparing a DNA-carbon nanotube hydrogel fiber and a DNA-carbon nanotube hydrogel fiber produced thereby. More specifically, the method for producing a DNA-carbon nanotube hydrogel fiber, characterized in that to control the physical properties of the DNA-carbon nanotube hydrogel fiber by immersing the DNA-carbon nanotube hydrogel fiber in a calcium salt solution will be. DNA-carbon nanotube hydrogel fiber prepared by controlling the physical properties according to the present invention can be utilized in artificial tissues, hydrogen peroxide sensor and actuator.

DNA-carbon nanotube hydrogel fiber, calcium ion, mechanical strength, swelling degree, modulus, artificial tissue, hydrogen peroxide sensor, actuator

Description

Method for producing DNA-carbon nanotube hydrogel fiber and DNA-carbon nanotube hydrogel fiber produced by the same

The present invention relates to a method for producing a DNA-carbon nanotube hydrogel fiber. More specifically, the present invention relates to a method of preparing a DNA-carbon nanotube hydrogel fiber by immersing a DNA-carbon nanotube hydrogel fiber in a calcium salt solution, and a DNA-carbon nanotube hydrogel fiber produced thereby.

Recently, in the field of biotechnology, tissue engineering for the treatment and regeneration of tissues has been developed. Tissue engineering is to collect the necessary tissue from the patient's body, separate the cells from the tissue pieces, and then cultivate the isolated cells to proliferate the cells as needed and plant them on a porous biodegradable polymer support. In this case, the hybrid cell / polymer construct is transplanted into the human body after in vitro culture. After transplantation, in most tissues and organs, oxygen and nutrients are supplied by the diffusion of body fluids until new blood vessels form. Then, when blood vessels in the human body grow and enter the cells, the blood is supplied, and the cells proliferate and differentiate to form new tissues and organs, and the polymer support is applied to a technique that is broken down and disappeared during that time.

Therefore, for such tissue engineering research, it is important to first prepare a biodegradable polymer support similar to biological tissue. The main requirement of the support material used for the regeneration of human tissue should be mechanical strength sufficient to serve as a substrate or support so that tissue cells can adhere to the material surface to form a three-dimensional structure of tissue. do. The scaffold should also serve as an intermediate barrier between the transplanted and host cells, which requires non-toxic biocompatibility without blood clotting or inflammatory reactions after transplantation. In addition, when transplanted cells function and function as new body tissues, the support must have biodegradability that can be completely degraded and disappeared in vivo.

Polymeric scaffolds for tissue engineering require high porosity in order to have a large surface area where high density cell adhesion can occur. In addition, after the support is implanted in vivo, it is necessary to have an open cell structure in which large pores and spaces are interconnected to allow formation of blood vessels and mass transfer of nutrient growth factors and hormones. And the support is required to adjust the porosity and the shape of the pores according to the characteristics of the tissue to be cultured.

Recently, various materials have been studied to mimic biological soft tissues such as tendons, muscles, arteries, skin and other organs. Biosoft tissue is very soft and mechanically strong. To date, it is difficult to simulate such biosoft tissues using synthetic materials.

However, research on the development of a composite support having a certain form and strength and a support for tissue engineering having elasticity and biological function of natural polymer using nanofiber, which is a synthetic material, has been made. However, in order to implement elastic tissue having high mechanical strength, it is necessary to implement a composite composite that can control mechanical strength. Research has been conducted to apply to artificial tissues or organs using synthetic materials such as reinforced hydrogel, but the actual porous soft material has a problem that the mechanical properties are very weak.

Indeed, many biological tissues have moderate or large mechanical ductility, so it is important to make the composites mechanically strong and robust. Creating materials with these properties is a major challenge to overcome in the study of artificial tissues and organs.

The present inventors continued to manufacture a support for tissue engineering that can solve the above problems. As a result, after preparing a carbon nanotube hydrogel fiber wrapped with DNA, and immersing the prepared DNA-carbon nanotube hydrogel fiber in a calcium salt solution, physical properties of the DNA-carbon nanotube hydrogel fiber It was found that can be controlled. Specifically, the present inventors have come to realize the present invention by controlling the concentration of calcium ions in the calcium salt solution to control the physical properties of DNA-wrapped carbon nanotube hydrogel fibers.

An object of the present invention is to provide a method for producing a DNA-carbon nanotube hydrogel fiber.

Another object of the present invention is to provide a method for preparing a DNA-carbon nanotube hydrogel fiber which can control physical properties.

Still another object of the present invention is to provide an artificial tissue having excellent softness and mechanical strength, which is prepared using a DNA-carbon nanotube hydrogel fiber with controlled physical properties.

Still another object of the present invention is to provide a hydrogen peroxide sensor manufactured using a DNA-carbon nanotube hydrogel fiber having excellent electrical conductivity.

In order to achieve the above object, the present invention comprises the steps of dissolving DNA in deionized water, and then adding a carbon nanotube to prepare a DNA-carbon nanotube hydrogel fiber (step 1); And depositing the DNA-carbon nanotube hydrogel fiber prepared in step 1 in a calcium salt solution (step 2).

Hereinafter, a method for preparing a DNA-carbon nanotube hydrogel fiber according to the present invention will be described in detail.

First, DNA is dissolved in deionized water, and carbon nanotubes are added to prepare DNA-carbon nanotube hydrogel fibers (step 1).

Typically, carbon nanotubes (CNTs) are carbon allotrope composed of carbon present in large quantities on earth. One carbon combines with other carbon atoms in a hexagonal honeycomb pattern to form a tube, and the diameter of the tube is nanometer (nm = 1 billionth of a meter).

Carbon nanotubes used in the present invention may be selected from single-walled carbon nanotubes (SWNT), multi-walled carbon nanotubes (MWNT) and mixtures thereof.

DNA is a large area of the phosphate backbone reacts with water, and many bases in the DNA bind to the carbon nanotubes so that the DNA can wrap the carbon nanotubes. The DNA-carbon nanotube hydrogel fiber made by the lapping may have a predetermined gap therein, thereby eliminating the bundling phenomenon of the carbon nanotubes.

DNA used in the present invention is preferably a DNA having a double helix structure of 1000 to 30,000 base pairs, but is not necessarily limited to the above numerical value. The DNA is not limited to any of the materials used, such as those extracted from natural organisms or those synthesized artificially. In the present invention, DNA obtained from salmon sperm was used, but is not necessarily limited thereto.

In one embodiment of the present invention, the DNA-carbon nanotube hydrogel fiber in step 1 is a step of dissolving DNA in deionized water, followed by sonication by adding carbon nanotubes; And adding the ultrasonicated DNA-carbon nanotube mixed solution to a coagulation bath containing an ionic liquid and ethanol, and rotating the coagulation bath to coagulate the DNA-carbon nanotube hydrogel fiber.

In the preparation of the DNA-carbon nanotube hydrogel fiber in step 1, the carbon nanotubes may be well dispersed in the solution by adding carbon nanotubes to deionized water in which DNA is dissolved, followed by sonication. In this case, the DNA may be dissolved in deionized water at 0.3 to 0.5% by weight, and the carbon nanotubes may be added at a concentration of 0.5 to 0.7% by weight for sonication. The sonication is preferably performed for 1 minute to 1 hour.

Thereafter, the ultrasonically treated DNA-carbon nanotube mixed solution is added to a coagulation bath containing an ionic liquid and ethanol, and then the coagulation bath is rotated to coagulate to prepare a DNA-carbon nanotube hydrogel fiber.

The ionic liquid may condense DNA as a hydrophilic ionic liquid to form an insoluble hydrogel, and may act as a coupling agent in the manufacture of carbon nanotubes wrapped with DNA by strongly interacting with carbon nanotubes. .

Examples of the ionic liquids include 1-ethyl-3-methyl imidazolium bromide, butylmethylimidazolium tetrafluoride, and ethyl. Imidazolium-based ionic liquids such as methylimidazolium bromide and the like can be used.

By using a coagulation solution containing the ionic liquid and the polar amphoteric ion solution in the ultrasonically treated DNA-carbon nanotube mixed solution, agglomeration of carbon nanotubes wrapped with DNA may be induced. The polar zwitterionic solution in the coagulation solution serves to assist the crosslinking reaction of DNA. Alcohol may be used as the polar amphoteric ion solution, and ethanol is preferably used. DNA cross-linked reactions can be made in DNA-wrapped carbon nanotubes, and the structure of dense carbon nanotubes can be made, and the agglomerated carbon nanotubes efficiently form a network to improve the performance of DNA-carbon nanotube hydrogel fibers. Can be improved.

The preparation of the DNA-carbon nanotube hydrogel fiber is as follows: When the coagulation bath is rotated after the ultrasonically treated DNA-carbon nanotube mixed solution is added to the coagulation bath through a small spinneret, the mixture is added to the coagulation bath. The solution is coagulated, and washing and drying may be further performed to prepare a DNA-carbon nanotube hydrogel fiber.

In the manufacturing process of the DNA-carbon nanotube hydrogel fiber, the coagulation bath is preferably rotated at 15 to 25 rpm, but is not limited thereto.

Next, the DNA-carbon nanotube hydrogel fiber prepared in step 1 may be immersed in a calcium salt solution to prepare a DNA-carbon nanotube hydrogel fiber according to the present invention (step 2).

By more specifically, form a DNA- CNT dihydro case of a gel of calcium ions fiber immersed in a solution dissolving the calcium salt, the calcium ions (Ca ^{2 +)} and the DNA cross-linked prepared in Step 1 as described above, DNA-wrapped carbon nanotubes are denser and more tightly linked.

 In step 2, an ion salt solution in which bivalent or more ions are capable of binding to DNA is used, without limitation, to form crosslinks with DNA, thereby more densely and strongly connecting the structure of the carbon nanotubes on which DNA is wrapped. Divalent or more ionic salt solutions capable of binding to DNA include calcium salt solutions or magnesium salt solutions, and calcium salt solutions are preferred.

The DNA-carbon nanotube hydrogel fiber according to the present invention thus prepared is formed in a porous sponge-like structure resembling a collagen fiber net in an extracellular matrix of an organism. That is, the DNA-carbon nanotube hydrogel sponge fiber according to the present invention has strong durability through DNA crosslinked by calcium ions and exhibits elasticity such as very soft biological tissue, and thus supports artificial tissues, tissue engineering supports, and the like. It has physical properties suitable for use as.

In addition, when the DNA-carbon nanotube hydrogel fiber is immersed in the calcium salt solution in step 2, by controlling the concentration of calcium ions in the calcium salt solution, the physical properties of the DNA-carbon nanotube hydrogel fiber, for example , Swelling degree, mechanical strength, modulus and the like can be changed.

Specifically, by changing the calcium ion concentration of the calcium salt solution within the range of 1 to 100 mM it can be controlled the physical properties of the finally prepared DNA-carbon nanotube hydrogel fiber.

As the concentration of calcium ions increases in the calcium salt solution used in step 2, the swelling degree of the prepared DNA-carbon nanotube hydrogel fiber may be lowered . Specifically, as the concentration of calcium ions in the calcium salt solution is higher than 1 mM in the range of 1 to 100 mM, the swelling degree of the prepared DNA-carbon nanotube hydrogel fiber may be lowered. Even within the concentration of the calcium ion is less than 1 mM, when the concentration of calcium ions increases, the swelling degree is lowered, the higher the concentration of more than 1 mM may be relatively greater swelling effect. Similarly, even in the range where the concentration of calcium ions is greater than 100 mM, as the concentration of calcium ions increases, the swelling degree is lowered. As the concentration is increased above 100 mM, the effect of lowering the swelling degree may be relatively insignificant.

In addition, as the concentration of calcium ions in the calcium salt solution increases, the mechanical strength of the prepared DNA-carbon nanotube hydrogel fiber may increase. Specifically, as the concentration of calcium ions in the calcium salt solution is higher than 1 mM in the range of 1 to 100 mM, the mechanical strength of the prepared DNA-carbon nanotube hydrogel fiber may be increased. Even within the concentration of the calcium ion is less than 1 mM, the increase in the concentration of calcium ions increases the mechanical strength, the higher the concentration of more than 1 mM may be relatively greater effect of increasing the mechanical strength. Similarly, even in the range where the concentration of calcium ions is greater than 100 mM, as the concentration of calcium ions increases, the mechanical strength is lowered. As the concentration increases above 100 mM, the effect of increasing the mechanical strength may be relatively insignificant.

The higher the concentration of calcium ions in the calcium salt solution, the higher the modulus of the prepared DNA-carbon nanotube hydrogel fiber. Specifically, as the concentration of calcium ions in the calcium salt solution is higher than 1 mM in the range of 1 to 100 mM, the modulus of the prepared DNA-carbon nanotube hydrogel fiber may be increased. Even within the range where the concentration of calcium ions is less than 1 mM, the modulus increases as the concentration of calcium ions increases. As the concentration increases above 1 mM, the modulus increase effect may be relatively greater. Similarly, even in the range where the concentration of calcium ions is greater than 100 mM, as the concentration of calcium ions increases, the modulus decreases. As the concentration increases above 100 mM, the modulus increase effect may be relatively insignificant.

The reason why the physical properties can be controlled as described above, when the DNA is wrapped carbon nanotubes wrapped in calcium salt solution, the DNA forms a cross-linking more tightly and more strongly connected. This is considered to be because an ionic bond between Ca ²⁺ ions and PO ₂ ⁻ (of DNA) is achieved (see Example 1 and FIG. 3 below). As such, as the crosslinking density of the DNA increases, the carbon nanotubes on which the DNA is wrapped can form a denser network. Densely networked, tightly coupled DNA-carbon nanotubes have less water penetration, resulting in lower swelling and increased mechanical strength and modulus. Therefore, an increase in the concentration of the calcium salt of calcium ions (Ca ^{2 +)} in the solution, DNA is therefore to form a cross-linked more densely stronger connection, the degree of swelling is dropping of the carbon nanotube with the DNA lapping, mechanical strength and modulus Will increase.

In the present invention, a solution in which divalent or more ions capable of binding to DNA may be used to control the physical properties of the carbon nanotubes in which DNA is wrapped. Specific examples include calcium salt solutions, and calcium chloride solution may be used as a solution in which calcium ions are dissolved.

The present invention provides an artificial tissue produced using a DNA-carbon nanotube hydrogel fiber that has strong durability and exhibits elasticity such as very soft biological tissue.

In another aspect, the present invention provides a hydrogen peroxide sensor manufactured using a DNA-carbon nanotube hydrogel fiber having excellent electrical conductivity.

In another aspect, the present invention provides an actuator prepared using a DNA-carbon nanotube hydrogel fiber that causes modification to electrical stimulation.

The present invention provides a method for preparing DNA-carbon nanotube hydrogel fibers whose physical properties can be controlled by immersing the DNA-carbon nanotube hydrogel fibers in a calcium salt solution. The DNA-carbon nanotube hydrogel fiber prepared by the above method may be utilized as an artificial tissue, a hydrogen peroxide sensor, an actuator, and the like.

Hereinafter, preferred examples are provided to aid the understanding of the present invention, but the following examples are merely illustrative of the present invention, and various changes and modifications can be made within the scope and spirit of the present invention. It is obvious to the skilled person, and it is natural that such variations and modifications fall within the scope of the appended claims.

< Example >

Example  One

After dissolving DNA obtained from salmon sperm in deionized water (ca. 20,000bp, purchased from Sigma-Aldrich, Inc., USA) at 2% w / w, single-walled carbon nanotubes (Carbon Nanotechnologies Co. , USA) was added to prepare a mixed solution in the form of a gel. To the mixed solution was added dropwise 1-ethyl-3-methyl imidazolium bromide (Solvent-Innovation Co., Cologne, Germany) to a final concentration of about 5% w / w. The mixed solution was injected into the coagulation bath containing 1-ethyl-3-methyl imidazolium bromide and ethanol in a 9: 1 weight ratio at a rate of 1.5 mLmin ^-1 through a needle having a diameter of 1 mm, and then the coagulation bath. Was spun at 15 rpm and solidified for 30 minutes. The coagulated fiber was washed with ethanol and deionized water and dried to prepare a DNA-carbon nanotube hydrogel fiber, which was photographed with a scanning electron microscope and shown in FIG. Thereafter, the DNA-carbon nanotube hydrogel fiber thus prepared is immersed in a calcium chloride solution (calcium ion concentration of 100 mM), then taken out, washed, and dried to prepare the DNA-carbon nanotube hydrogel fiber of the present invention. This was taken with a scanning electron microscope and shown in FIG.

As shown in (a) and (b) of FIG. 1, in the case of the DNA-carbon nanotube hydrogel fiber of the present invention treated with a solution containing calcium ions, the diameter of the nanofibers was reduced. It can be seen that the porosity is further improved. In addition, it can be seen that very similar to the structure of the collagen fibers present in the extracellular matrix of the living body.

In addition, the surface of the DNA-carbon nanotube hydrogel fiber prepared in Example 1 was photographed with a scanning electron microscope, and is shown in FIG. 2, and an electron energy loss spectrometer (EELS) was performed on the DNA-carbon nanotube hydrogel fiber. The elemental map measured by) is shown in FIG. 3. As shown in Figure 2 it can be seen that the DNA-carbon nanotube hydrogel fiber prepared according to the present invention has a porous network structure. Referring to Figure 3, the carbon nanotube DNA- calcium ion in the hydrogel fiber (Ca ^{2 +)} and phosphate ions (PO ₂ ^-) prepared in accordance with the present invention and the degree of dispersion of the found to be almost identical, these calcium it can be seen that the ionic cross-linking occurs by a combination of DNA and ^- ions (Ca ^{2 +)} and phosphate ions (PO _2).

FIG. 4 is a scanning electron micrograph of the DNA-carbon nanotube hydrogel fibers prepared in Example 1 of the present invention, each of which is prepared by tying, twisting, and weaving each other. As shown in FIG. 4, the DNA-carbon nanotube hydrogel fiber prepared according to the present invention is not only soft, but also improves mechanical strength, and can be manufactured without breaking, tying, twisting, and weaving together. Therefore, when the DNA-carbon nanotube hydrogel fibers of the present invention are bundled, twisted, and woven together, artificial tissues and tissue engineering scaffolds can be adjusted to nanoscale and microscale.

< Experimental Example  1> DNA Carbon Nanotubes Hydrogel  Experiment to measure the effect of calcium ion addition on fiber

The effect of addition of calcium ions (Ca ^{2 +)} for the carbon nanotube wrapped with DNA was assessed by a solution phase cryo-TEM. After preparing a mixed solution in which DNA and carbon nanotubes were dissolved as in Example 1, DNA-carbon finally prepared by adding a solution having calcium ions concentrations of 0, 20 μM and 1 mM, respectively, to the solution. The cryo-TEM was measured on the nanotube hydrogel fiber and is shown in FIG. 5. As shown in Figure 5, it can be seen that the diameter and density of the formed DNA-carbon nanotube hydrogel fiber bundles depend on the concentration of calcium ions added, the lower the concentration produced a larger diameter bundle. When processing the DNA- carbon nanotubes in a solution comprising a high concentration of calcium ions (Ca ^{2 +)} from the Experimental Example 1, increases the cross-linking density of the DNA- DNA CNT hydrogel fiber of the invention is the compactness It can be seen that a network is formed.

< Experimental Example  2> manufactured by controlling the concentration of calcium ions DNA Carbon Nanotubes Hydrogel  Measurement of Water Absorption of Fiber

The DNA-carbon nanotube hydrogel fibers were treated with calcium chloride solutions having calcium ion concentrations of 100 mM, 10 mM, and 1 mM, respectively, and then measured for water absorption (swelling ratio) for each, and are shown in FIG. 6. In FIG. 6, the water absorption rate is expressed by quantifying the increased weight before and after swelling for the DNA-carbon nanotube hydrogel fiber treated with the calcium chloride solution.

The assay circles, white circles and assay squares in FIG. 6 show the water absorption of DNA-carbon nanotube hydrogel fibers treated with calcium chloride solutions at 100 mM, 10 mM and 1 mM concentrations, respectively. As can be seen in Figure 6, it can be seen that the water absorption rate of the DNA-carbon nanotube hydrogel fiber treated with a high concentration of calcium ion solution is the lowest. This is because the DNA-carbon nanotube hydrogel fiber treated with a high concentration of calcium ion solution forms a more densely crosslinked network and has a low swelling degree. When the DNA-carbon nanotube hydrogel fiber is treated with a solution containing calcium ions from Experimental Example 2, the water absorption and swelling degree of the DNA-carbon nanotube hydrogel fiber is controlled by adjusting the calcium ion concentration of the solution used. It can be seen that.

< Experimental Example  3> manufactured by controlling the concentration of calcium ions DNA Carbon Nanotubes Hydrogel  Measurement of the mechanical strength of the fiber

In Experimental Example 3, the mechanical strength of the DNA-carbon nanotube hydrogel fiber prepared by controlling the concentration of calcium ions was measured, and the results are shown in Table 1 below. The mechanical strength of the prepared hydrogel fiber was measured using the Dual-Mode lever arm system of Aurora Scientific (Canada). After fixing one side of the hydrogel fiber, a stress was applied to the opposite hydrogel fiber connected to the lever arm system using the lever arm system to measure the strain of the hydrogel fiber relative to the applied stress. The Young's modulus of hydrogel fibers by mechanical strength test was calculated based on the slope of the strain versus the initial stress. In Experimental Example 3, mechanical strength means energy stored in a material, and toughness was calculated up to a break point (below the stress-strain curve). Since some of the stored energy is recovered by the elastic process, the toughness represents the energy dissipated during the fracture process. In Experimental Example 3, the stored energy (mechanical strength) was calculated as "toughness" and was chosen because this variable is very much related to the mechanical strength of the material. We found that the linear stress-strain relationship is U = 1 / 2σ.ε = 1 / 2E.ε ² = 1 / 2σ ² / E (where σ and ε are break stress and strain, respectively, and E is Young's modulus). Young's modulus), and toughness was calculated. The unit of toughness is kJ / m ³ . In addition, the unit of tensile strength which is the stress at break is kPa.

The mechanical properties of DNA-carbon nanotube hydrogel fibers treated with calcium salt solution according to the present invention and DNA gel fibers without using carbon nanotubes were measured and shown in Table 1 below.

Preparation of the DNA-carbon nanotube hydrogel fiber treated with the calcium salt solution was carried out in the same manner as in Example 1 except that only the concentration of calcium ions (1, 10 and 100 Mm) was changed. Preparation of DNA gel fibers without using carbon nanotubes of the comparative example was carried out in the same manner as in Example 1 except that carbon nanotubes were not used, and the concentration of calcium ions to be treated was 1, 10 and 100 Mm, respectively. It was set as.

As shown in Table 1, it can be seen that both the mechanical strength and modulus of the DNA-carbon nanotube hydrogel fiber of the present invention treated with an equivalent amount of calcium ion solution were significantly increased than the DNA gel fiber.

In addition, through Table 1, it can be seen that the DNA-carbon nanotube hydrogel fiber according to the present invention can control the physical properties of the finally prepared DNA-carbon nanotube hydrogel fiber by controlling the concentration of calcium ions. That is, using the DNA-carbon nanotube hydrogel fiber according to the present invention can be prepared for the support for tissue engineering to be used in artificial tissues or organs suitable for the desired biological tissue.

< Experimental Example  4> DNA Carbon Nanotubes Hydrogel  Electrical Conductivity Measurement of Fiber

In Experimental Example 4, the use of the DNA-carbon nanotube hydrogel fiber prepared according to Example 1 as a biosensor for H ₂ O ₂ detection was evaluated electrochemically.

Application of an anode potential to the peroxide solution results in H ₂ O ₂ oxidation according to Scheme 1 below:

H ₂ O ₂ → ^{_{O 2 + 2H + + 2e -}} .

The steady-state current was measured to select the working potential for sensor operation. FIG. 7 shows two current reactions of DNA-carbon nanotube hydrogel fibers, obtained at a predetermined potential with respect to an Ag / AgCl reference electrode. As shown in FIG. 7, a relatively large current was detected at increasing anode potential using DNA-carbon nanotube hydrogel fiber electrodes in 5 mM H ₂ O ₂ solution. From the above results, it can be seen that the DNA-carbon nanotube hydrogel fiber prepared according to the present invention can be used as a hydrogen peroxide sensor.

Hydrogen peroxide is a substance that plays an important role in normal heart function and is closely related to the development of heart disease. Therefore, it can be seen that the DNA-carbon nanotube hydrogel fiber according to the present invention can be used as a sensor that matches the response of the heart muscle.

As described above, the DNA-wrapped carbon nanotube, DNA-carbon nanotube hydrogel fiber according to the present invention can be used as an artificial tissue because it is very similar to the structure of collagen fibers present in the extracellular matrix of the biological breakfast. . Since the DNA-carbon nanotube hydrogel fiber according to the present invention has electrical conductivity, it can be used for hydrogen peroxide sensors, actuators and energy storage materials.

Figure 1 (a) is a photograph taken with a scanning electron microscope of the DNA-carbon nanotube hydrogel fiber before treatment with calcium chloride solution in Example 1 of the present invention, Figure 1 (b) is the DNA-carbon It is a photograph taken by scanning electron microscope of the DNA-carbon nanotube hydrogel fiber of the present invention prepared by immersing the nanotube hydrogel fiber in calcium chloride solution (100 mM), washed and dried.

Figure 2 is a scanning electron micrograph taken on the surface of the DNA-carbon nanotube hydrogel fiber prepared in Example 1 of the present invention.

3 is an elemental map measured by an electron energy loss spectrometer (EELS) for the DNA-carbon nanotube hydrogel fiber prepared in Example 1 of the present invention.

FIG. 4 is a scanning electron micrograph of the DNA-carbon nanotube hydrogel fibers prepared in Example 1 of the present invention, each of which is prepared by tying, twisting, and weaving each other.

FIG. 5 is a photograph illustrating cryo-TEM of DNA-carbon nanotube hydrogel fibers prepared by treating with calcium, respectively, solutions having concentrations of 0, 20 μM and 1 mM in Experimental Example 1 of the present invention. .

Figure 6 is a graph showing the results of measuring the water absorption after treating the DNA-carbon nanotube hydrogel fiber with 100 mM, 10 mM and 1 mM calcium chloride solution, respectively in Experimental Example 2 of the present invention.

7 is a graph showing two current reactions obtained by applying an anode current in two kinds of solutions to a DNA-carbon nanotube hydrogel fiber electrode in Experimental Example 4 of the present invention.

Claims (15)

Dissolving DNA in deionized water, and then adding carbon nanotubes to prepare DNA-carbon nanotube hydrogel fibers (step 1); And Immersing the DNA-carbon nanotube hydrogel fiber prepared in step 1 in a calcium salt solution (step 2); DNA-carbon nanotube hydrogel fiber production method comprising a. The method according to claim 1, When the DNA-carbon nanotube hydrogel fiber is immersed in the calcium salt solution in step 2, the swelling degree, mechanical strength or modulus of the DNA-carbon nanotube hydrogel fiber is adjusted by adjusting the concentration of calcium ions in the calcium salt solution. Method of producing a DNA-carbon nanotube hydrogel fiber, characterized in that the manufacturing by adjusting. The method according to claim 2, The higher the concentration of calcium ions, the swelling degree of the prepared DNA-carbon nanotube hydrogel fiber, characterized in that the method of producing a DNA-carbon nanotube hydrogel fiber. The method of claim 3, Method of producing a DNA-carbon nanotube hydrogel fiber, characterized in that the swelling degree of the prepared DNA-carbon nanotube hydrogel fiber is lowered as the concentration of the calcium ion is higher than 1 mM. The method according to claim 2, The higher the concentration of calcium ions, the higher the mechanical strength of the prepared DNA-carbon nanotube hydrogel fiber is characterized in that the method for producing a DNA-carbon nanotube hydrogel fiber. The method of claim 5, Method of producing a DNA-carbon nanotube hydrogel fiber, characterized in that the mechanical strength of the prepared DNA-carbon nanotube hydrogel fiber increases as the concentration of the calcium ion is higher than 1 mM. The method according to claim 2, The method of manufacturing a DNA-carbon nanotube hydrogel fiber, characterized in that the modulus of the prepared DNA-carbon nanotube hydrogel fiber increases as the concentration of calcium ions increases. The method of claim 7, The method of producing a DNA-carbon nanotube hydrogel fiber, characterized in that the modulus of the prepared DNA-carbon nanotube hydrogel fiber becomes higher as the concentration of the calcium ion is higher than 1 mM. The method according to claim 1, The method of producing a DNA-carbon nanotube hydrogel fiber, characterized in that the concentration of calcium ions in the calcium salt solution is 1 to 100 mM. The method according to claim 1, In step 1, the DNA-carbon nanotube hydrogel fiber dissolves DNA in deionized water, followed by sonication by adding carbon nanotubes; And rotating the coagulation bath by adding the ultrasonically treated DNA-carbon nanotube mixed solution to a coagulation bath containing an ionic liquid and ethanol, and coagulating the same to prepare a DNA-carbon nanotube hydrogel fiber. Method for producing a DNA-carbon nanotube hydrogel fiber, characterized in that it is prepared by. The method of claim 10, The ionic liquid is an imidazolium-based ionic liquid, characterized in that the manufacturing method of DNA-carbon nanotube hydrogel fiber. The method of claim 11, The imidazolium-based ionic liquid is DNA-carbon nanotube hydrogel fiber, characterized in that 1-ethyl-3-methyl imidazolium bromide, butylmethylimidazolium terafluoride or ethylmethylimidazolium bromide Manufacturing method. A DNA-carbon nanotube hydrogel fiber, wherein DNA is wrapped around a carbon nanotube, which is prepared by the method of any one of claims 1 to 12. Artificial tissue prepared using the DNA-carbon nanotube hydrogel fiber of claim 13. Hydrogen peroxide sensor prepared using the DNA-carbon nanotube hydrogel fiber of claim 13.

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