Supramolecular nano self-assembly, preparation method and application thereof
By preparing supramolecular nano-self-assembled structures with a particle size of <10nm, the problems of instability and slow response in the detection of electrochemically active bacteria in the prior art have been solved, and rapid visualization screening and stability improvement of electrochemically active bacteria have been achieved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- SANQUAN COLLEGE OF XINXIANG MEDICAL COLLEGE
- Filing Date
- 2026-02-12
- Publication Date
- 2026-06-05
AI Technical Summary
Existing WO3-based electrochromic materials suffer from heterogeneous instability and slow response when used for the detection of electrochemically active bacteria, making it difficult to achieve rapid visual screening.
Supramolecular nano-self-assembled structures containing 70%–90% carbon dots and 10%–30% methylene blue, with a particle size <10 nm, were prepared. These structures exhibited good water solubility and intracellular and extracellular electron transfer capabilities. They were prepared via hydrothermal reaction and self-assembly methods, enabling rapid and visual screening.
It enables rapid and visual screening of electrochemically active bacteria, improves response rate and stability, and enhances intracellular and extracellular electron transfer capabilities.
Smart Images
Figure CN122146838A_ABST
Abstract
Description
Technical Field
[0002] This invention belongs to the field of preparation of supramolecular nanomaterials and rapid visual screening of electrochemically active bacteria, specifically relating to a supramolecular nano self-assembled body, its preparation method and application. Background Technology
[0004] Electrochemically active bacteria are a type of bacteria that can exchange electrons with extracellular acceptors. They are widely present in various natural and artificial environments and play an important role in biogeochemical cycles, biosensing, environmental remediation, and bioenergy recovery.
[0005] Currently, WO3-based electrochromic methods have been widely used for the visual detection of electrochemically active bacteria. However, these electrochromic materials are in a heterogeneous and unstable state during application and mainly rely on the extracellular electron transfer ability of electrochemically active bacteria, resulting in a slow response. Summary of the Invention
[0007] To address the shortcomings of existing technologies, the present invention aims to provide a supramolecular nano-self-assembled structure, its preparation method, and its applications. The supramolecular nano-self-assembled structure provided by this invention exhibits good water solubility and combines the intracellular and extracellular electron transfer capabilities of carbon dots with the redox color-changing ability of methylene blue, enabling rapid and visual screening of electrochemically active bacteria.
[0008] To achieve the above objectives, the present invention adopts the following technical solution:
[0009] The first aspect of this invention provides a supramolecular nano-self-assembled structure, wherein the mass percentage of carbon dots in the supramolecular nano-self-assembled structure is 70%~90%, and the mass percentage of methylene blue is 10%~30%; the particle size of the supramolecular nano-self-assembled structure is <10nm, it has good water solubility, and its characteristic absorption peak is at 665nm. The supramolecular nano-self-assembled structure combines the electron transfer capability of carbon dots with the redox color-changing capability of methylene blue, which can simultaneously accelerate the intracellular and extracellular electron transfer process of electrochemically active bacteria, thereby achieving rapid and visual screening of electrochemically active bacteria; the carbon dots are prepared by hydrothermal reaction of amine compounds and citric acid at 150~230℃.
[0010] The second aspect of this invention provides a method for preparing supramolecular nano-self-assembled structures, the specific preparation steps of which are as follows: amine compounds and citric acid are dissolved in ultrapure water and subjected to a hydrothermal reaction at 150~230℃ for 8~20h. After the reaction is completed, the reaction solution is purified and freeze-dried to obtain carbon dot powder. Then, methylene blue and carbon dot powder are added to ultrapure water to carry out a self-assembly reaction. After the reaction is completed, the mixture is purified and freeze-dried to obtain supramolecular nano-self-assembled structures.
[0011] Furthermore, the amine compound is one or more of ethylenediamine, triethylamine, diethylenetriamine, and urea.
[0012] Furthermore, the mass ratio of the amine compound to citric acid is 1:3 to 1:10; the mass ratio of methylene blue to carbon dot powder is 1:2 to 1:8.
[0013] Furthermore, the reaction temperature of the self-assembly reaction process is 10~40℃, and the reaction time is 0.5~2h.
[0014] Furthermore, the purification process involves first filtering through a 0.1~0.45μm aqueous microporous membrane, and then dialysis through a 500~3000Da dialysis bag for 5~20 hours.
[0015] The third aspect of this invention provides an application of supramolecular nano-self-assembled organisms in the rapid visual screening of electrochemically active bacteria. The specific process is as follows: a reaction system is formed by mixing supramolecular nano-self-assembled organisms, microorganisms, electron donors, KH2PO4, K2HPO4 and ultrapure water. The pH value of the reaction system is 6-9. When the microorganisms are electrochemically active bacteria, the reaction temperature is 20-35℃. Within 20 minutes of reaction time, the reaction system exhibits a visual color change, and the absorbance in the 665nm visible light region decreases significantly.
[0016] Furthermore, the microbial density of the reaction system is 1×10⁻⁶. 5 ~1×10 10 CFU / mL.
[0017] Furthermore, the electron donor is glucose, sodium lactate, or yeast extract, more preferably nutrient-rich yeast extract, with a concentration preferably of 0.1~0.5 g / L.
[0018] Furthermore, the microorganism is the electrochemically active bacterium Shewanella sp.
[0019] Compared with existing technologies, the beneficial effects of this invention are as follows: the supramolecular nano-self-assembled particles prepared by this invention have a particle size of <10nm, possessing both the excellent electron transfer capability of carbon dots and the color-changing ability of methylene blue, and exhibiting good water solubility and stability. When used for screening electrochemically active bacteria, it can enter the interior of microorganisms, simultaneously accelerating the intracellular and extracellular electron transfer capability of microorganisms and improving the electrochromic response rate. Attached Figure Description
[0021] Figure 1 The images show transmission electron microscopy (TEM) images of supramolecular nano-assemblies (A) and their water solubility stability (B).
[0022] Figure 2 These are characteristic absorption peaks of the supramolecular nano-self-assembled organisms prepared in Example 2.
[0023] Figure 3 This is a visualization of the supramolecular nano-self-assembled structure prepared in Example 2 responding to different microorganisms.
[0024] Figure 4 This is the visible absorption peak response diagram of the supramolecular nano-self-assembled organism prepared in Example 2 to the electrochemically active bacteria Shewanella sp. Detailed Implementation
[0026] The technical solution and its effects of the present invention will be described in detail below with reference to specific embodiments. These embodiments are implemented based on the technical solution of the present invention, providing detailed implementation methods and specific operating procedures; however, the scope of protection of the present invention is not limited to the following embodiments.
[0027] Example 1
[0028] 0.1 g of diethylenetriamine and 1 g of citric acid were dissolved in 30 mL of ultrapure water and subjected to hydrothermal reaction at 200 °C for 15 h. After the reaction was completed, the reaction solution was filtered through a 0.22 μm aqueous microporous membrane and dialyzed through a 1000 Da dialysis bag for 8 h to obtain a carbon dot solution. After freeze-drying, carbon dot powder was obtained. 0.1 g of methylene blue and 0.4 g of carbon dot powder were added to 50 mL of ultrapure water and subjected to self-assembly reaction at 25 °C for 1.5 h. After the reaction was completed, the reaction solution was filtered through a 0.22 μm aqueous microporous membrane and dialyzed through a 1000 Da dialysis bag for 5 h to obtain a supramolecular nano-self-assembled solution. Finally, supramolecular nano-self-assembled powder was obtained by freeze-drying.
[0029] Example 2
[0030] 0.25 g of diethylenetriamine and 1 g of citric acid were dissolved in 30 mL of ultrapure water and subjected to hydrothermal reaction at 200 °C for 15 h. After the reaction was completed, the reaction solution was filtered through a 0.22 μm aqueous microporous membrane and dialyzed through a 1000 Da dialysis bag for 8 h to obtain a carbon dot solution. The carbon dot powder was obtained by freeze-drying. 0.1 g of methylene blue and 0.4 g of carbon dot powder were added to 50 mL of ultrapure water and subjected to self-assembly reaction at 25 °C for 1.5 h. After the reaction was completed, the reaction solution was filtered through a 0.22 μm aqueous microporous membrane and dialyzed through a 500 Da dialysis bag for 5 h to obtain a supramolecular nano-self-assembled solution. Finally, the supramolecular nano-self-assembled powder was obtained by freeze-drying.
[0031] Example 3
[0032] 0.1 g of ethylenediamine and 1 g of citric acid were dissolved in 30 mL of ultrapure water and subjected to hydrothermal reaction at 210 °C for 15 h. After the reaction was completed, the reaction solution was filtered through a 0.22 μm aqueous microporous membrane and dialyzed through a 1000 Da dialysis bag for 8 h to obtain a carbon dot solution. The carbon dot powder was obtained by freeze-drying. 0.1 g of methylene blue and 0.4 g of carbon dot powder were added to 50 mL of ultrapure water and subjected to self-assembly reaction at 25 °C for 1.5 h. After the reaction was completed, the reaction solution was filtered through a 0.22 μm aqueous microporous membrane and dialyzed through a 500 Da dialysis bag for 5 h to obtain a supramolecular nano-self-assembled solution. Finally, the supramolecular nano-self-assembled powder was obtained by freeze-drying.
[0033] Example 4
[0034] 0.25 g of ethylenediamine and 1 g of citric acid were dissolved in 30 mL of ultrapure water and subjected to hydrothermal reaction at 220 °C for 15 h. After the reaction was completed, the reaction solution was filtered through a 0.22 μm aqueous microporous membrane and dialyzed through a 1000 Da dialysis bag for 8 h to obtain a carbon dot solution. The carbon dot powder was obtained by freeze-drying. 0.1 g of methylene blue and 0.4 g of carbon dot powder were added to 50 mL of ultrapure water and subjected to self-assembly reaction at 25 °C for 1.5 h. After the reaction was completed, the reaction solution was filtered through a 0.22 μm aqueous microporous membrane and dialyzed through a 500 Da dialysis bag for 5 h to obtain a supramolecular nano-self-assembled solution. Finally, the supramolecular nano-self-assembled powder was obtained by freeze-drying.
[0035] Example 5
[0036] 0.25 g of triethylamine and 1 g of citric acid were dissolved in 30 mL of ultrapure water and subjected to hydrothermal reaction at 220 °C for 10 h. After the reaction was completed, the reaction solution was filtered through a 0.22 μm aqueous microporous membrane and dialyzed through a 1000 Da dialysis bag for 12 h to obtain a carbon dot solution. The carbon dot powder was obtained by freeze-drying. 0.1 g of methylene blue and 0.5 g of carbon dot powder were added to 50 mL of ultrapure water and subjected to self-assembly reaction at 25 °C for 2 h. After the reaction was completed, the reaction solution was filtered through a 0.22 μm aqueous microporous membrane and dialyzed through a 500 Da dialysis bag for 5 h to obtain a supramolecular nano-self-assembled solution. Finally, the supramolecular nano-self-assembled powder was obtained by freeze-drying.
[0037] Example 6
[0038] 0.25 g of urea and 1 g of citric acid were dissolved in 30 mL of ultrapure water and subjected to a hydrothermal reaction at 220 °C for 15 h. After the reaction was completed, the reaction solution was filtered through a 0.22 μm aqueous microporous membrane and dialyzed through a 500 Da dialysis bag for 12 h to obtain a carbon dot solution. The carbon dot powder was obtained by freeze-drying. 0.1 g of methylene blue and 0.5 g of carbon dot powder were added to 50 mL of ultrapure water and subjected to a self-assembly reaction at 25 °C for 2 h. After the reaction was completed, the reaction solution was filtered through a 0.22 μm aqueous microporous membrane and dialyzed through a 500 Da dialysis bag for 5 h to obtain a supramolecular nano-self-assembled body solution. Finally, the supramolecular nano-self-assembled body powder was obtained by freeze-drying.
[0039] The morphology of the supramolecular nano-assemblies prepared in Example 2 was analyzed. From the transmission electron microscopy (TEM) images (… Figure 1 As can be seen from A), this supramolecular nano-assembly has a relatively uniform particle size, with an average particle size of about 4 nm, which gives it good stability in aqueous solution. Figure 1 (B)
[0040] The characteristic absorption peaks of the supramolecular nano-assemblies prepared in Example 2 were analyzed. From the UV-Vis absorption spectrum ( Figure 2 It can be seen that the supramolecular nano-self-assembled structure retains the characteristic absorption peak of methylene blue in the visible region (665 nm), which enables its visualization in the screening of electrochemically active bacteria.
[0041] A reaction solution containing 7.22 g / L K₂HPO₄, 1.16 g / L KH₂PO₄, 0.1 g / L yeast extract, and 0.1 g / L supramolecular nano-assemblies was prepared. The solution was then purified by purging with N₂ and sterilizing using a 0.22 μm filter. 1.9 mL of the reaction solution was transferred to a 2 mL anaerobic flask, and 100 μL of bacterial culture was added (the final bacterial density of the reaction system was 1 × 10⁻⁶). 8 After sealing (CFU / mL), the anaerobic bottles were used as control group 1 (without microorganisms but with supramolecular nano-assemblies) and control group 2 (with microorganisms but without supramolecular nano-assemblies). The anaerobic bottles were incubated in a 25°C incubator for 5 minutes.
[0042] The test results of the supramolecular nano-self-assembled organisms prepared in Example 2 showed that, in the microbial tests of Shewanella sp., Rhodococcus pyridinivorans sp., Escherichia coli sp., Proteus vulgaris sp., and pseudomonas sp., only the typical electrochemically active bacterium Shewanella sp. exhibited rapid and visible color change. Figure 3 The absorbance in the visible region at 664 nm decreased significantly. Figure 4 ).
[0043] The results of the color change response time of supramolecular nano-self-assembled structures prepared in different embodiments to Shewanella sp. are shown in Table 1.
[0044] Table 1. Color-changing response of supramolecular nano-assemblies to Shewanella sp.
[0045] Project Examples Change in absorbance at 665 nm within 5 minutes Complete color change time (min) Example 1 1.1 10 Example 2 2.0 5 Example 3 0.8 13 Example 4 1.9 6 Example 5 1.1 10 Example 6 0.8 13 Control group 1 0 — Control group 2 0 —
[0046] As can be seen from the experimental results in Table 1, the supramolecular nano-self-assembled bodies prepared in each embodiment of the present invention have good rapid visual recognition ability for electrochemically active bacteria.
[0047] The foregoing has shown and described the basic principles, main features and advantages of the present invention. Various changes and modifications can be made to the present invention without departing from the spirit and scope thereof, and all such changes and modifications fall within the scope of the present invention as claimed.
Claims
1. A supramolecular nano-self-assembled structure, characterized in that: The supramolecular nano-assemblies contain 70%–90% carbon dots and 10%–30% methylene blue by mass. The supramolecular nano-assemblies have a particle size <10 nm, good water solubility, and a characteristic absorption peak at 665 nm. They combine the electron transfer capabilities of carbon dots with the redox color-changing ability of methylene blue, simultaneously accelerating the intracellular and extracellular electron transfer process of electrochemically active bacteria, thus enabling rapid and visual screening of these bacteria. The carbon dots are prepared by a hydrothermal reaction of amine compounds and citric acid at 150–230 °C.
2. A method for preparing the supramolecular nano-self-assembled structure according to claim 1, characterized in that... The specific preparation steps are as follows: amine compounds and citric acid are dissolved in ultrapure water and hydrothermally reacted at 150~230℃ for 8~20h. After the reaction is completed, the reaction solution is purified and freeze-dried to obtain carbon dot powder. Then, methylene blue and carbon dot powder are added to ultrapure water to carry out a self-assembly reaction. After the reaction is completed, supramolecular nano self-assembled bodies are obtained after purification and freeze-drying.
3. The method for preparing supramolecular nano-self-assembled structures according to claim 2, characterized in that: The amine compound is one or more of ethylenediamine, triethylamine, diethylenetriamine, and urea.
4. The method for preparing supramolecular nano-self-assembled structures according to claim 2, characterized in that: The mass ratio of the amine compound to citric acid is 1:3 to 1:10; the mass ratio of methylene blue to carbon dot powder is 1:2 to 1:
8.
5. The method for preparing supramolecular nano-self-assembled structures according to claim 2, characterized in that: The self-assembly reaction process is carried out at a temperature of 10~40℃ and for a time of 0.5~2h.
6. The method for preparing supramolecular nano-self-assembled structures according to claim 2, characterized in that: The purification process involves first filtering through a 0.1~0.45μm aqueous microporous membrane, followed by dialysis through a 500~3000Da dialysis bag for 5~20 hours.
7. The application of the supramolecular nano-self-assembled structure according to claim 1 in the rapid visual screening of electrochemically active bacteria.
8. The application according to claim 7, characterized in that... The specific process is as follows: a reaction system is formed by mixing supramolecular nano-self-assembled bodies, microorganisms, electron donors, KH2PO4, K2HPO4 and ultrapure water. The pH value of the reaction system is 6~9. When the microorganisms are electrochemically active bacteria, the reaction temperature is 20~35℃. Within 20 minutes of reaction time, the reaction system shows a visible color change, and the absorbance in the 665nm visible light region decreases significantly.
9. The application according to claim 8, characterized in that: The microbial density of the reaction system is 1×10⁻⁶. 5 ~1×10 10 CFU / mL; the electron donor is glucose, sodium lactate or yeast extract, with a concentration of 0.1~0.5 g / L.
10. The application according to claim 7 or 8, characterized in that: The microorganism in question is the electrochemically active bacterium Shewanella sp.