Preparation method and application of bakuchiol carbon quantum dots
By preparing psoralen carbon quantum dots with uniform particle size and strong fluorescence, the problems of poor water solubility of psoralen and high cost and toxicity of traditional carbon quantum dots have been solved, achieving highly efficient and specific antibacterial effect and high bioavailability against Staphylococcus aureus.
Patent Information
- Application Number
- CN202511434412.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-10-09
- Publication Date
- 2026-01-27
AI Technical Summary
Existing psoralen has poor water solubility and low bioavailability, and its preparation process is complex and unstable. Traditional carbon quantum dots are costly, have high toxicity risks, and have poor specific antibacterial effects against Staphylococcus aureus.
Psoralen carbon quantum dots were prepared by a process involving dissolution, solvothermal reaction, and post-treatment. Ethyl acetate was used as the solvent, and carbon quantum dots were synthesized in a high-pressure reactor at a specific temperature and time. Post-treatment included filtration and vacuum drying, resulting in carbon quantum dots with uniform particle size and strong fluorescence.
This study achieved highly efficient and specific antibacterial effects of psoralen carbon quantum dots, which are effective against Staphylococcus aureus, while reducing preparation costs and toxicity risks, and improving bioavailability and fluorescence performance.
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Figure CN121406322A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The application belongs to the technical field of nanomaterials and antibacterial technology, and specifically discloses a preparation method and application of bakuchiol carbon quantum dots. BACKGROUND
[0002] Bakuchiol is a natural monoterpenoid phenolic active ingredient of Psoralea corylifolia Linn. of Leguminosae, has pharmacological activities such as anti-inflammatory, antioxidant and anti-acne, is praised as “plant retinol”, and has potential application value in skin care and biological medicine fields. However, bakuchiol has problems of poor water solubility (water solubility is 0.86 mg / L) and low bioavailability, and has limited effect when directly applied, is easily affected by environmental pH and enzymatic hydrolysis, and thus is limited in clinical application. At present, although some studies attempt to prepare bakuchiol into nano-suspension, liposome and other dosage forms, there are problems of complex preparation process, solvent residue (such as dimethyl sulfoxide) and poor stability, and it is difficult to meet the actual application requirements.
[0003] As a new type of nanomaterial, carbon quantum dots (CQDs) have excellent optical properties (fluorescent stability, anti-photobleaching), low biological toxicity and good biocompatibility, and show broad prospects in the fields of antibacterial and biological imaging. The existing preparation of carbon quantum dots mostly adopts “bottom-up method”, but has the following deficiencies: firstly, the carbon source is mostly chemical synthesis precursor (such as citric acid, o-phenylenediamine), which has high cost and toxicity risk; secondly, the pretreatment process of natural raw materials (such as chitosan, mango peel) is complex, and is affected by the production place and ingredient difference of raw materials, resulting in unstable performance of carbon quantum dots; thirdly, most of the antibacterial carbon quantum dots are broad-spectrum antibacterial type, which easily destroys the balance of bacterial flora, and there are few reports on specific antibacterial carbon quantum dots for Staphylococcus aureus (common gram-positive pathogenic bacteria, which easily causes skin infection and medical device related infection), and high concentration (>500 μg / mL) is needed to achieve effective inhibition, which increases the application cost and potential toxicity. SUMMARY
[0004] In view of the deficiencies of the prior art, the application provides a green and simple preparation method of bakuchiol carbon quantum dots, and application of the carbon quantum dots in specific inhibition of Staphylococcus aureus and fluorescence detection, so as to realize high-value utilization of bakuchiol and precise regulation of antibacterial performance of carbon quantum dots.
[0005] The preparation method of bakuchiol carbon quantum dots provided by the application comprises the following steps: (1) dissolving: dissolving bakuchiol in ethyl acetate, ultrasonic dispersion, and obtaining a light yellow transparent solution; (2) solvothermal reaction: transferring the light yellow transparent solution obtained in step (1) into a high-pressure reaction kettle for reaction, and obtaining a bakuchiol carbon quantum dot dispersion; (3) Post-processing: After the reaction in step (2) is completed, the dispersion liquid is naturally cooled to room temperature, and the psoralen phenol carbon quantum dots are filtered to obtain a psoralen phenol carbon quantum dot solution with a fluorescence effect. The carbon quantum dot solution is concentrated by rotary evaporation, and vacuum dried to obtain psoralen phenol carbon quantum dots.
[0006] As a preferred scheme of the preparation method of the psoralen phenol carbon quantum dots with antibacterial properties of the present application: (1) The dissolving is: 50-70 mg of psoralen phenol is accurately weighed and dissolved in 30 mL of ethyl acetate, preferably 60 mg of psoralen phenol is weighed and dissolved in 30 mL of ethyl acetate, and ultrasonic dispersion is performed for 5-10 min to obtain a psoralen phenol-ethyl acetate mixed solution with a concentration of 1667-2333 μg / mL, and preferably a mixed solution with a concentration of 2000 μg / mL.
[0007] (2) The solvothermal reaction is: the mixed solution obtained in step (1) is transferred to a polytetrafluoroethylene liner, sealed in a stainless steel high-pressure reaction kettle, the oven temperature is set to 120-180 ℃, and the reaction time is 9-15 h, preferably the oven temperature is 150 ℃, and the reaction time is 12 h.
[0008] (3) The post-processing is: after the reaction in step (2) is completed, the dispersion liquid is naturally cooled to room temperature, and the psoralen phenol carbon quantum dots are filtered to obtain a psoralen phenol carbon quantum dot solution with a fluorescence effect. The carbon quantum dot solution is concentrated by rotary evaporation, and vacuum dried to obtain psoralen phenol carbon quantum dots.
[0009] The psoralen phenol carbon quantum dots obtained by the above method have a particle size range of 2-16 nm; and are used in the fields of preparation of antibacterial materials, fluorescence detection, etc.
[0010] The psoralen phenol carbon quantum dots are used for antibacterial objects of Staphylococcus aureus; and the antibacterial use concentration of the psoralen phenol carbon quantum dots is ≥250 μg / mL.
[0011] The beneficial effects of the present application are as follows: (1) The psoralen phenol carbon quantum dots prepared by the present application have the characteristics of high fluorescence intensity, good dispersibility, and uniform particle size; and are suitable for various systems such as biological medicines.
[0012] (2) The psoralen phenol carbon quantum dots prepared by the present application have outstanding antibacterial specificity, are effective only for Staphylococcus aureus, have no effect on other strains, and avoid bacterial flora imbalance.
[0013] (3) The natural psoralen phenol is used as a carbon source to replace traditional chemical synthesis precursors (such as citric acid), thereby reducing the risk of toxicity; the ethyl acetate is a low-toxicity solvent, is easy to recover, conforms to the concept of green chemistry, and has high raw material utilization rate without complex pretreatment. BRIEF DESCRIPTION OF DRAWINGS
[0014] Figure 1 is a TEM image of the bakuchiol carbon quantum dots prepared in Example 1.
[0015] Figure 2 is a histogram of the particle size distribution of the bakuchiol carbon quantum dots prepared in Example 1, according to the TEM image.
[0016] Figure 3 is an infrared spectrum of the bakuchiol carbon quantum dots prepared in Example 1.
[0017] Figure 4 is an ultraviolet spectrum of the bakuchiol carbon quantum dots prepared in Example 1.
[0018] Figure 5 is a bacteriostatic effect diagram of the bakuchiol carbon quantum dots prepared in Example 1 on E. coli, C. albicans, A. niger and S. aureus.
[0019] Figure 6 is a fluorescence emission spectrum of the bakuchiol carbon quantum dots prepared in Example 1 under different excitation wavelengths.
[0020] Figure 7 is a fluorescence emission spectrum of the bakuchiol carbon quantum dots prepared in Example 2 under different excitation wavelengths.
[0021] Figure 8 is a fluorescence emission spectrum of the bakuchiol carbon quantum dots prepared in Example 3 under different excitation wavelengths.
[0022] Figure 9 is a fluorescence emission spectrum of the bakuchiol carbon quantum dots prepared in Example 4 under different excitation wavelengths.
[0023] Figure 10 is a fluorescence emission spectrum of the bakuchiol carbon quantum dots prepared in Example 5 under different excitation wavelengths.
[0024] Figure 11 is a fluorescence emission spectrum of the bakuchiol carbon quantum dots prepared in Example 6 under different excitation wavelengths.
[0025] Figure 12 is a fluorescence emission spectrum of the bakuchiol carbon quantum dots prepared in Example 7 under different excitation wavelengths.
[0026] Figure 13 is a light irradiation picture of the bakuchiol carbon quantum dots prepared in Example 1 and Comparative Examples 1 and 2.
[0027] Figure 14 is a ultraviolet light irradiation picture of the bakuchiol carbon quantum dots prepared in Example 1 and the apigenin carbon quantum dots prepared in Comparative Example 3. DETAILED DESCRIPTION
[0028] The present application will be further described in detail below with reference to specific examples. These examples are only intended to illustrate the present application and not to limit the scope of the present application in any way. Example 1
[0029] Take 60 mg of psoralen and dissolve it in 30 mL of ethyl acetate, the concentration of psoralen is 2000 μg / mL. It is observed that psoralen is easily soluble in ethyl acetate. The mixed solution is transferred to a polytetrafluoroethylene liner, sealed in a stainless steel autoclave, and the oven temperature is set to 150 ℃, and the reaction time is 12 h. After the reaction is completed, it is naturally cooled to room temperature, and the reaction solution is filtered with a 0.22 μm filter membrane to obtain a psoralen carbon quantum dot dispersion. The filtered carbon quantum dot dispersion is concentrated by rotary evaporation at 40-60 ℃, and then vacuum dried at 40 ℃ for 8 h to obtain a powdered psoralen carbon quantum dot.
[0030] Figure 1 is a TEM image of the psoralen carbon quantum dots prepared in Example 1, the size range is between 2.0-16.0 nm, and the average size is 7.0 nm.
[0031] Figure 2 is a histogram of the particle size distribution of the carbon quantum dots obtained by statistical analysis according to the TEM image of Example 1, in which the number of the 6-8 nm particle size segment is the most, showing that the particle size distribution of the carbon quantum dots in this system is relatively concentrated, and slightly biased towards smaller particle size. According to the fitting results of the distribution curve, it is approximately normally distributed, indicating that the particle size is well controllable in the synthesis system. These results show that the current preparation process can efficiently obtain carbon quantum dots with uniform particle size.
[0032] Figure 3 is an infrared spectrum of the psoralen carbon quantum dots prepared in Example 1, in which the stretching vibration peak of -OH (or -NH) appears at 3327.7 cm -1 , there are weak peaks at 2962.1 cm -1 and 2924.9 cm -1 , corresponding to the asymmetric and symmetric stretching vibrations of C-H, respectively, 1700.9 cm -1 and 1770.4 cm -1 are the stretching vibration peaks of the carbonyl (C=O) group, 1240.1 cm -1 , 1166.4 cm -1 , and 1058.30 cm -1 are the C-O-C and C-O stretching vibration peaks. It is proved that the carbon quantum dots are rich in hydroxyl (-OH), carboxyl (-COOH), and ether (C-O-C) groups on the surface.
[0033] Figure 4is the UV spectrum of the bakuchiol carbon quantum dots prepared in Example 1, there is an obvious main absorption peak at 290 nm, and the carbon quantum dot solution has a relatively wide and slow peak at 350-450 nm, which may be caused by the surface state luminescence or quantum confinement effect of the nanostructure of the carbon quantum dots.
[0034] Figure 5 is the antibacterial effect diagram of the bakuchiol carbon quantum dots prepared in Example 1 on Escherichia coli, Candida albicans, Aspergillus niger, and Staphylococcus aureus. There is no obvious antibacterial effect on Escherichia coli, Candida albicans, and Aspergillus niger, but there is an antibacterial effect on Staphylococcus aureus. When the concentration is 2000 μg / mL, the diameter of the antibacterial circle is 13 mm; when the concentration is 1000 μg / mL, the diameter of the antibacterial circle is 11 mm; when the concentration is 500 μg / mL, the diameter of the antibacterial circle is 10 mm; when the concentration is 250 μg / mL, the diameter of the antibacterial circle is 10 mm; and when the concentration is 125 μg / mL, the diameter of the antibacterial circle is not obvious. It can be seen that when the concentration of the bakuchiol carbon quantum dots is greater than 250 μg / mL, the bakuchiol carbon quantum dots have a good antibacterial effect on Staphylococcus aureus. Example 2
[0035] Take 70 mg of bakuchiol and dissolve it in 30 mL of ethyl acetate, at this time the concentration of the bakuchiol ethyl acetate solution is 2333 μg / mL. Transfer the mixed solution to a polytetrafluoroethylene liner, seal it in a stainless steel high-pressure reaction kettle, set the oven temperature to 150 ℃, and the reaction time to 12 h. After the reaction is completed, naturally cool to room temperature, filter the reaction liquid with a 0.22 μm filter membrane, and obtain a bakuchiol carbon quantum dot dispersion liquid. Example 3
[0036] Take 50 mg of bakuchiol and dissolve it in 30 mL of ethyl acetate, at this time the concentration of the bakuchiol ethyl acetate solution is 1667 μg / mL. Transfer the mixed solution to a polytetrafluoroethylene liner, seal it in a stainless steel high-pressure reaction kettle, set the oven temperature to 150 ℃, and the reaction time to 12 h. After the reaction is completed, naturally cool to room temperature, filter the reaction liquid with a 0.22 μm filter membrane, and obtain a bakuchiol carbon quantum dot dispersion liquid. Example 4
[0037] Take 60 mg of bakuchiol and dissolve it in 30 mL of ethyl acetate, at this time the concentration of the bakuchiol ethyl acetate solution is 2000 μg / mL. Transfer the mixed solution to a polytetrafluoroethylene liner, seal it in a stainless steel high-pressure reaction kettle, set the oven temperature to 180 ℃, and the reaction time to 12 h. After the reaction is completed, naturally cool to room temperature, filter the reaction liquid with a 0.22 μm filter membrane, and obtain a bakuchiol carbon quantum dot dispersion liquid. Example 5
[0038] Take 60 mg of psoralen dissolved in 30 mL of ethyl acetate, at this time the concentration of psoralen ethyl acetate solution is 2000 μg / mL. The mixed solution is transferred to a polytetrafluoroethylene liner, sealed in a stainless steel autoclave, the oven temperature is set to 120 ℃, and the reaction time is 12 h. After the reaction is completed, it is naturally cooled to room temperature, and the reaction liquid is filtered with a 0.22 μm filter membrane to obtain a psoralen carbon quantum dot dispersion. Example 6
[0039] Take 60 mg of psoralen dissolved in 30 mL of ethyl acetate, at this time the concentration of psoralen ethyl acetate solution is 2000 μg / mL. The mixed solution is transferred to a polytetrafluoroethylene liner, sealed in a stainless steel autoclave, the oven temperature is set to 150 ℃, and the reaction time is 9 h. After the reaction is completed, it is naturally cooled to room temperature, and the reaction liquid is filtered with a 0.22 μm filter membrane to obtain a psoralen carbon quantum dot dispersion. Example 7
[0040] Take 60 mg of psoralen dissolved in 30 mL of ethyl acetate, at this time the concentration of psoralen ethyl acetate solution is 2000 μg / mL. The mixed solution is transferred to a polytetrafluoroethylene liner, sealed in a stainless steel autoclave, the oven temperature is set to 150 ℃, and the reaction time is 15 h. After the reaction is completed, it is naturally cooled to room temperature, and the reaction liquid is filtered with a 0.22 μm filter membrane to obtain a psoralen carbon quantum dot dispersion.
[0041] Figures 6-8 Figure 8 is a fluorescence emission spectrum of psoralen carbon quantum dots prepared in Examples 1-3 at different concentrations. As the concentration of psoralen increases, the content of small molecule carbon precursors in the system gradually increases, and the fluorescence intensity of the carbon quantum dots shows a clear upward trend.
[0042] Figure 6 , 9 Figure 10 is a fluorescence emission spectrum of psoralen carbon quantum dots prepared in Examples 1, 4-5 at three different temperatures. When the reaction temperature is 150 ℃, the fluorescence intensity is the highest.
[0043] Figure 6 , 11 Figure 12 is a fluorescence emission spectrum of psoralen carbon quantum dots prepared in Examples 1, 6-7 at three different reaction times. As the reaction time increases, the fluorescence intensity of the carbon quantum dots shows a trend of first increasing and then decreasing. Comparative Example 1
[0044] Take 60 mg of psoralen and dissolve it in 30 mL of ethanol. At this time, the concentration of the psoralen ethanol solution is 2000 μg / mL. Transfer the mixed solution to a polytetrafluoroethylene liner, seal it in a stainless steel autoclave, set the oven temperature to 150°C, and react for 12 h. After the reaction is completed, naturally cool it to room temperature, filter the reaction liquid with a 0.22 μm filter membrane, and obtain a psoralen carbon quantum dot dispersion liquid. Under the irradiation of a 365 nm ultraviolet lamp, no obvious fluorescence phenomenon is observed. Comparative Example 2
[0045] Take 60 mg of psoralen and dissolve it in 30 mL of DMSO. At this time, the concentration of the psoralen DMSO solution is 2000 μg / mL. Transfer the mixed solution to a polytetrafluoroethylene liner, seal it in a stainless steel autoclave, set the oven temperature to 150°C, and react for 12 h. After the reaction is completed, naturally cool it to room temperature, filter the reaction liquid with a 0.22 μm filter membrane, and obtain a psoralen carbon quantum dot dispersion liquid. Under the irradiation of a 365 nm ultraviolet lamp, a weak fluorescence phenomenon is observed. Comparative Example 3
[0046] Take 60 mg of apigenin and dissolve it in 30 mL of ethyl acetate. Transfer the mixed solution to a polytetrafluoroethylene liner, seal it in a stainless steel autoclave, set the oven temperature to 150°C, and react for 12 h. After the reaction is completed, naturally cool it to room temperature, filter the reaction liquid with a 0.22 μm filter membrane, and obtain an apigenin carbon quantum dot dispersion liquid. Under the irradiation of a 365 nm ultraviolet lamp, a weak fluorescence phenomenon is observed.
[0047] Figure 13 The ultraviolet light irradiation picture of the psoralen carbon quantum dot solution prepared by different solvents in Example 1 and Comparative Examples 1-2 is shown. It is observed that the psoralen carbon quantum dots prepared by using ethyl acetate as the solvent have the best fluorescence performance, and psoralen is more easily dissolved in the ethyl acetate solution.
[0048] Figure 14 The ultraviolet light irradiation picture of the apigenin carbon quantum dot solution prepared in Comparative Example 3 is shown. It is observed that the carbon quantum dots prepared by using psoralen as the raw material have better fluorescence performance.
[0049] The specific conditions are not specified in the examples, and the conventional conditions are used. The reagents or instruments used are not specified by the manufacturer, and are all conventional products that can be purchased on the market. The methods used in the present application are conventional methods in the art, unless otherwise specified. The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modification made to the above examples in accordance with the technical essence of the present application is included within the scope of the present application.
Claims
1. A method for preparing psoralen carbon quantum dots, characterized in that, The preparation method of the carbon quantum dots is as follows: 1) Dissolve psoralen powder in ethyl acetate and disperse it by ultrasonication to obtain a psoralen-ethyl acetate mixed solution; 2) Transfer the mixed solution from step 1) to a high-pressure reactor with a polytetrafluoroethylene liner for solvothermal reaction; 3) After the reaction in step 2) is completed, the mixture is allowed to cool naturally to room temperature. The reaction solution is then filtered through a 0.22 μm organic phase filter membrane to obtain a psoralen carbon quantum dot solution. The solution is then concentrated by rotary evaporation and vacuum dried to obtain powdered psoralen carbon quantum dots.
2. The method for preparing psoralen carbon quantum dots according to claim 1, characterized in that, In step 1), the concentration of the psoralen-ethyl acetate mixed solution is 1667-2333 μg / mL; the ultrasonic dispersion power is 550 W, the frequency is 40 kHz, and the ultrasonic time is 5-10 min.
3. The method for preparing psoralen carbon quantum dots according to claim 1, characterized in that, In step 2), the temperature of the solvothermal reaction is 120-180℃, the reaction time is 9-15 h, and the volume of the high-pressure reactor is 50 mL.
4. The method for preparing psoralen carbon quantum dots according to claim 1, characterized in that, In step 3), the rotary evaporation concentration temperature is 40-60 ℃, and the vacuum drying is carried out at 40 ℃ for 8 h.
5. A psoralen carbon quantum dot prepared according to any one of claims 1-4, characterized in that, The particle size range of the carbon quantum dots is 2-16 nm.
6. An application of psoralen carbon quantum dots prepared according to any one of claims 1-4, characterized in that, The carbon quantum dots are used to prepare antibacterial materials and fluorescent detection reagents.
7. The application of psoralen carbon quantum dots according to claim 6, characterized in that, The target bacteria is Staphylococcus aureus.
8. The application of psoralen carbon quantum dots according to claim 6, characterized in that, The concentration of psoralen carbon quantum dots used for antibacterial purposes is ≥250 μg / mL.