A fluorescent nucleic acid material with humidity indication function and preparation method thereof

Abstract

The present invention relates to the technical field of biomaterials and humidity-responsive materials, and primarily to a fluorescent nucleic acid material with a humidity indication function and a method for preparing the same. The fluorescent nucleic acid material with a humidity indication function described in the present invention is an ionic nucleic acid complex material obtained by synthesizing single-stranded deoxyribonucleic acid, didodecyldimethylammonium bromide, and a quaternary ammonium salt compound containing a tetraphenylethylene structure in an aqueous phase, and combining them with electrostatic forces as the primary force. The fluorescent nucleic acid material with a humidity indication function prepared by the present invention can produce phase changes and fluorescence signal changes under humidity stimulation. The fluorescent nucleic acid material with a humidity indication function prepared by the present invention can be applied to humidity monitoring and other related fields.

Description

Technical Field

[0001] The present invention relates to the technical field of biomaterials and humidity-responsive materials, and mainly relates to a fluorescent nucleic acid material with a humidity indication function and a preparation method thereof. Background Art

[0002] Humidity monitoring has important applications in many areas, including our daily lives. For example, the production and storage of pharmaceuticals, food, chemicals, and precision instruments require accurate and real-time humidity monitoring. Materials used for humidity monitoring are stimuli-responsive functional materials that produce a detectable signal in response to humidity stimuli. Research in fields such as biology and biomedicine also requires humidity indicator materials to be flexible, biocompatible, and biodegradable.

[0003] Biomaterials based on biomolecules possess inherent advantages in terms of biocompatibility and biodegradability. DNA molecules are one of the most important natural biological resources and have been developed into a variety of functional materials. By functionalizing DNA molecules, DNA-functional materials can respond to various external stimuli, such as changes in the double helix structure of nucleic acid molecules caused by light stimulation. However, most current DNA-based stimulus-responsive materials can only be used in aqueous environments and are difficult to stimulate in solvent-free environments. This is mainly due to the conditions required for the existence and working environment of DNA molecules.

[0004] In recent years, a new class of thermotropic liquid crystal materials composed of DNA molecules and quaternary ammonium surfactants has been developed. These materials, in the absence of solvents, can exhibit distinct changes in physical and chemical properties in response to a variety of external stimuli. Currently, by designing different surfactant molecules, various stimulus-responsive properties have been achieved for these solvent-free DNA thermotropic liquid crystals, including thermochromic, electrochromic, magnetoresponsive, photochromic, and photophase transitions. However, solvent-free DNA thermotropic liquid crystal materials capable of producing fluorescence signal changes in response to humidity stimulation have yet to be reported, limiting the application of these materials in humidity indication and detection. Therefore, the development of fluorescent DNA materials with humidity indication capabilities is of great significance for expanding the application of nucleic acid materials in basic research and technology. Summary of the Invention

[0005] In view of this, an object of the present invention is to provide a fluorescent nucleic acid material with humidity indication function and a preparation method thereof.

[0006] The technical solutions of the present invention are as follows:

[0007] The invention provides a fluorescent nucleic acid material with a humidity indication function. The raw materials for preparing the fluorescent nucleic acid material include single-stranded deoxyribonucleic acid, didodecyldimethylammonium bromide and a quaternary ammonium salt compound containing a tetraphenylethylene structure.

[0008] In the present invention, the number of bases in the single-stranded deoxyribonucleic acid is 20 to 100.

[0009] In the present invention, the quaternary ammonium salt compound containing a tetraphenylethylene structure is N,N,N-trimethyl-8-(4-(2-(4-octyloxyphenyl)-1,2-diphenylvinyl)phenoxy)octylammonium bromide.

[0010] In the present invention, the method for preparing the fluorescent nucleic acid material with humidity indication function comprises:

[0011] First, didodecyldimethylammonium bromide and a quaternary ammonium salt compound containing a tetraphenylethylene structure are dissolved in water to prepare an aqueous solution containing the two surfactants. The aqueous solution containing the two surfactants is then mixed with an aqueous solution of single-stranded deoxyribonucleic acid. The resulting mixture is shaken and centrifuged, the supernatant is discarded, and the resulting precipitated complex is collected. The resulting precipitated complex is freeze-dried to produce a fluorescent nucleic acid material with a humidity indication function.

[0012] In the present invention, the method for preparing the fluorescent nucleic acid material with a humidity indication function comprises the following steps: the concentration of the single-stranded deoxyribonucleic acid in the aqueous solution of the single-stranded deoxyribonucleic acid is 2-3 mmol / L; the concentration of didodecyldimethylammonium bromide in the aqueous solution containing two surfactants is 20-30 mmol / L; and the molar concentration of the quaternary ammonium salt compound containing a tetraphenylethylene structure in the aqueous solution containing the two surfactants is 2-3% of the molar concentration of didodecyldimethylammonium bromide.

[0013] In the present invention, in the method for preparing the fluorescent nucleic acid material with humidity indication function, in the mixed solution, the molar ratio of the single-stranded deoxyribonucleic acid to didodecyldimethylammonium bromide, calculated in terms of the number of bases, is 1:1 to 1:5.

[0014] In the present invention, in the method for preparing the fluorescent nucleic acid material with humidity indication function, the shaking time is 15 minutes, and the freeze-drying time is 1 to 3 hours.

[0015] The present invention provides a fluorescent nucleic acid material with a humidity indication function and a preparation method thereof. The fluorescent nucleic acid material with a humidity indication function and the preparation method thereof have the following characteristics:

[0016] 1. The fluorescent nucleic acid material with humidity indication function obtained in the present invention is an ion complex formed by deoxyribonucleic acid, didodecyldimethylammonium bromide and a quaternary ammonium salt compound containing a tetraphenylethylene structure through electrostatic force.

[0017] 2. The fluorescent nucleic acid material with humidity indication function obtained by the present invention can produce a phase change from an ordered crystal structure to a disordered fluid structure under humidity stimulation, and this phase change simultaneously induces a change in the fluorescent properties of the material.

[0018] 3. The fluorescent nucleic acid material with humidity indication function obtained by the present invention uses 300nm ultraviolet light as the excitation light source, and the fluorescence intensity generated at 390nm is linearly related to the relative humidity value. Using this linear relationship, the fluorescent nucleic acid material with humidity indication function obtained by the present invention can indicate the relative humidity value.

[0019] 4. The fluorescent nucleic acid material with humidity indication function obtained by the present invention can indicate the relative humidity of the environment within 4 minutes.

[0020] 5. The fluorescent nucleic acid material with humidity indication function obtained in the present invention can be used as a humidity indicator material. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a comparison of the X-ray small-angle scattering patterns of the fluorescent nucleic acid material with humidity indication function described in Example 1 before and after humidity stimulation.

[0022] Figure 2 The fluorescent nucleic acid material with humidity indication function described in Example 1 changes in fluorescence signal within 5 minutes under the condition of relative humidity of 80% and with 300nm ultraviolet light as the excitation light source.

[0023] Figure 3 The fluorescent nucleic acid material with a humidity indication function described in Example 1 was left to stand for 4 minutes at a relative humidity of 40-100%, with 300 nm ultraviolet light as the excitation light source. The relationship between the fluorescence intensity of the fluorescent nucleic acid material with a humidity indication function at 390 nm and the relative humidity described in Example 1 was obtained. DETAILED DESCRIPTION

[0024] The present invention provides a fluorescent nucleic acid material with a humidity indication function and a method for preparing the same. Those skilled in the art can refer to the content of this article and appropriately improve the process parameters to achieve this. It should be noted that all similar substitutions and modifications are obvious to those skilled in the art and are considered to be included in the present invention. The methods and applications of the present invention have been described through preferred embodiments. Relevant personnel can obviously modify or appropriately change and combine the methods and applications herein without departing from the content, spirit and scope of the present invention to implement and apply the technology of the present invention.

[0025] The present invention will be further described below in conjunction with the embodiments:

[0026] Example 1:

[0027] Didodecyldimethylammonium bromide and N,N,N-trimethyl-8-(4-(2-(4-octyloxyphenyl)-1,2-diphenylvinyl)phenoxy)octylammonium bromide were prepared into an aqueous solution containing two surfactants, wherein the concentrations of didodecyldimethylammonium bromide and N,N,N-trimethyl-8-(4-(2-(4-octyloxyphenyl)-1,2-diphenylvinyl)phenoxy)octylammonium bromide were 20 mmol / L and 600 μmol / L, respectively. 880 μL of the aqueous solution containing the two surfactants and 200 μL of a 2 mmol / L aqueous solution of single-stranded deoxyribonucleic acid (22 base units) were mixed in a centrifuge tube and shaken for 15 minutes. The mixture was then centrifuged at a relative centrifugal force of 6124 g for 10 minutes. The supernatant was discarded, the resulting precipitate was collected, and the resulting precipitate was freeze-dried for 2 hours to produce the fluorescent nucleic acid material with humidity indication function of the present invention. After testing, it was found that the fluorescent nucleic acid material with humidity indication function prepared in the present invention is a thermotropic liquid crystal material.

[0028] The prepared fluorescent nucleic acid material with humidity indication function has an X-ray small-angle scattering test spectrum before being treated in a humid environment and an X-ray small-angle scattering test spectrum after being left in an environment with a relative humidity of 100% for 1 hour. Figure 1 As shown, according to Figure 1 , it was concluded that the prepared fluorescent nucleic acid material with humidity indication function can be transformed into a disordered fluid under the stimulation of humidity conditions.

[0029] The prepared fluorescent nucleic acid material with humidity indication function was placed under 80% relative humidity and used 300nm ultraviolet light as the excitation light source. The fluorescence spectrum of the prepared fluorescent nucleic acid material with humidity indication function changed within 5 minutes as shown in the following figure: Figure 2 As shown, according to Figure 2, it was concluded that the prepared fluorescent nucleic acid material with humidity indication function can complete the change of fluorescence signal within 4 minutes and reach a stable state.

[0030] The prepared fluorescent nucleic acid material with humidity indication function takes 40% relative humidity as the starting condition, increases the relative humidity to 100%, and uses 300nm ultraviolet light as the excitation light source. The relationship between the fluorescence intensity at 390nm and the relative humidity of the fluorescent nucleic acid material with humidity indication function after standing for 4 minutes under each humidity condition is as follows: Figure 3 As shown, according to Figure 3 It was concluded that the fluorescence intensity of the prepared fluorescent nucleic acid material with humidity indication function at 390nm showed a linear relationship with the relative humidity within the relative humidity range of 40% to 100%, indicating that the prepared fluorescent nucleic acid material with humidity indication function can be used as a relative humidity indicator material.

[0031] Example 2:

[0032] Didodecyldimethylammonium bromide and N,N,N-trimethyl-8-(4-(2-(4-octyloxyphenyl)-1,2-diphenylvinyl)phenoxy)octylammonium bromide were prepared into an aqueous solution containing two surfactants, wherein the concentrations of didodecyldimethylammonium bromide and N,N,N-trimethyl-8-(4-(2-(4-octyloxyphenyl)-1,2-diphenylvinyl)phenoxy)octylammonium bromide were 30 mmol / L and 600 μmol / L, respectively. 2 mL of the aqueous solution containing the two surfactants and 200 μL of a 2 mmol / L aqueous solution of single-stranded deoxyribonucleic acid (50 base units) were mixed in a centrifuge tube and shaken for 15 minutes. The mixture was then centrifuged at a relative centrifugal force of 6124 g for 10 minutes. The supernatant was discarded, the resulting precipitate was collected, and the resulting precipitate was freeze-dried for 2 hours to produce the fluorescent nucleic acid material with humidity indication function of the present invention. After testing, it was found that the fluorescent nucleic acid material with humidity indication function prepared in the present invention is a thermotropic liquid crystal material.

[0033] The prepared fluorescent nucleic acid material with a humidity indication function takes 40% relative humidity as the starting condition, increases the relative humidity to 100%, and uses 300nm ultraviolet light as the excitation light source. After the fluorescent nucleic acid material with a humidity indication function is allowed to stand for 4 minutes under each humidity condition, the relationship between the fluorescence intensity at 390nm and the change in relative humidity shows a linear relationship, indicating that the fluorescent nucleic acid material with a humidity indication function prepared by the present invention can be used as a relative humidity indicator material.

[0034] Comparative Example 1:

[0035] Didodecyldimethylammonium bromide and N,N,N-trimethyl-8-(4-(2-(4-octyloxyphenyl)-1,2-diphenylvinyl)phenoxy)octylammonium bromide were prepared into an aqueous solution containing two surfactants, wherein the concentrations of didodecyldimethylammonium bromide and N,N,N-trimethyl-8-(4-(2-(4-octyloxyphenyl)-1,2-diphenylvinyl)phenoxy)octylammonium bromide were 20 mmol / L and 100 μmol / L, respectively. 880 μL of the aqueous solution containing the two surfactants and 200 μL of a 2 mmol / L single-stranded deoxyribonucleic acid (22 base units) aqueous solution were mixed in a centrifuge tube and shaken for 15 minutes. The mixture was then centrifuged at a relative centrifugal force of 6124 g for 10 minutes. The supernatant was discarded and the resulting precipitate was collected. The resulting precipitate was freeze-dried for 2 hours to prepare a solvent-free nucleic acid ion complex material. After testing, it was found that the solvent-free nucleic acid ion complex material prepared in Comparative Example 1 was a thermotropic liquid crystal material, but did not have the humidity monitoring function using fluorescence changes as an indication signal.

[0036] Comparative Example 2:

[0037] Didodecyldimethylammonium bromide and N,N,N-trimethyl-8-(4-(2-(4-octyloxyphenyl)-1,2-diphenylvinyl)phenoxy)octylammonium bromide were prepared into an aqueous solution containing two surfactants, wherein the concentrations of didodecyldimethylammonium bromide and N,N,N-trimethyl-8-(4-(2-(4-octyloxyphenyl)-1,2-diphenylvinyl)phenoxy)octylammonium bromide were 20 mmol / L and 2 mmol / L, respectively. 880 μL of the aqueous solution containing the two surfactants and 200 μL of a 2 mmol / L single-stranded deoxyribonucleic acid (22 base units) aqueous solution were mixed in a centrifuge tube and shaken for 15 minutes. The mixture was then centrifuged at a relative centrifugal force of 6124 g for 10 minutes. The supernatant was discarded and the resulting precipitate was collected. The resulting precipitate was freeze-dried for 2 hours to prepare a solvent-free nucleic acid ion complex material. After testing, it was found that the solvent-free nucleic acid ion complex material prepared in Comparative Example 2 was a thermotropic liquid crystal material, but did not have the humidity monitoring function using fluorescence changes as an indication signal.

[0038] Comparative Example 3:

[0039] Hexadecyltrimethylammonium bromide and N,N,N-trimethyl-8-(4-(2-(4-octyloxyphenyl)-1,2-diphenylvinyl)phenoxy)octylammonium bromide were prepared into an aqueous solution containing two surfactants, wherein the concentrations of hexadecyltrimethylammonium bromide and N,N,N-trimethyl-8-(4-(2-(4-octyloxyphenyl)-1,2-diphenylvinyl)phenoxy)octylammonium bromide were 20 mmol / L and 600 μmol / L, respectively. 880 μL of the aqueous solution containing the two surfactants and 200 μL of a 2 mmol / L single-stranded deoxyribonucleic acid (22 base units) aqueous solution were mixed in a centrifuge tube and shaken for 15 minutes. The mixture was then centrifuged at a relative centrifugal force of 6124 g for 10 minutes. The supernatant was discarded and the resulting precipitate was collected. The resulting precipitate was freeze-dried for 2 hours to prepare a solvent-free nucleic acid ion complex material. After testing, it was found that the solvent-free nucleic acid ion complex material prepared in Comparative Example 3 did not have the humidity monitoring function using fluorescence changes as an indication signal.

[0040] The above are only preferred embodiments of the present invention. It should be pointed out that those skilled in the art can make several improvements without departing from the principles of the present invention, and these improvements should also be considered as within the scope of protection of the present invention.

Claims

1. A method for preparing a fluorescent nucleic acid material with humidity indication function, characterized in that: include: First, didodecyldimethylammonium bromide and a quaternary ammonium salt compound containing a tetraphenylethylene structure are dissolved in water to prepare an aqueous solution containing two surfactants, and then the aqueous solution containing the two surfactants is mixed with an aqueous solution of single-stranded deoxyribonucleic acid, the obtained mixed solution is shaken and centrifuged, the supernatant is discarded and the obtained precipitated complex is collected, and the obtained precipitated complex is freeze-dried to prepare a fluorescent nucleic acid material with a humidity indication function; the quaternary ammonium salt compound containing a tetraphenylethylene structure is N,N,N -trimethyl-8-(4-(2-(4-octyloxyphenyl)-1,2-diphenylvinyl)phenoxy)octylammonium bromide, in the mixed solution, the single-stranded deoxyribonucleic acid, calculated in terms of the number of bases, the molar ratio of the single-stranded deoxyribonucleic acid to didodecyldimethylammonium bromide is 1:1 to 1:5, and the molar concentration of the quaternary ammonium salt compound containing a tetraphenylethylene structure in the aqueous solution containing the two surfactants is 2 to 3% of the molar concentration of didodecyldimethylammonium bromide.

2. The method for preparing the fluorescent nucleic acid material with humidity indication function according to claim 1, characterized in that: In the mixed solution, the concentration of single-stranded deoxyribonucleic acid in the aqueous solution of single-stranded deoxyribonucleic acid is 2-3 mmol / L, and the concentration of didodecyldimethylammonium bromide in the aqueous solution containing the two surfactants is 20-30 mmol / L.

3. The method for preparing the fluorescent nucleic acid material with humidity indication function according to claim 1, characterized in that: The shaking time is 15 minutes, and the freeze-drying time is 1 to 3 hours.

4. The nucleic acid material prepared according to claims 1 to 3 is a fluorescent nucleic acid material with humidity indication function.

5. The fluorescent nucleic acid material with humidity indication function according to claim 4, characterized in that: The contained deoxyribonucleic acid is a single-stranded deoxyribonucleic acid with a base number of 20 to 100.

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