A dual-emission silicon quantum dot, its preparation method and application
The dual-emission silicon quantum dots prepared by a one-step hydrothermal method and dialysis drying process solve the problem of insufficient dual-emission wavelength in the prior art, realize dual-emission characteristics under the same excitation light source, improve the accuracy and sensitivity of fluorescent probes, and are suitable for cell imaging.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2023-11-03
- Publication Date
- 2026-03-06
AI Technical Summary
There are few silicon quantum dots with dual emission wavelengths in existing technologies, which makes fluorescent probes susceptible to interference from environmental factors, affecting detection accuracy and sensitivity.
Dual-emission silicon quantum dots were prepared by using 3-aminopropyltrimethoxysilane and orthocyanin as reaction precursors and through a one-step hydrothermal process combined with dialysis and drying.
The prepared dual-emission silicon quantum dots exhibit fluorescence emission peaks in both blue and green regions under the same excitation light source. They are stable, have low biotoxicity, and are suitable for cell imaging, thus improving the accuracy and sensitivity of detection.
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Figure CN117701276B_ABST
Abstract
Description
Technical Field
[0001] This application relates to the fields of chemistry and nanomaterials science and technology, and more specifically, to a dual-emission silicon quantum dot, its preparation method, and its applications. Background Technology
[0002] Silicon quantum dots (SiQDs) are zero-dimensional silicon-based fluorescent nanomaterials with excellent photostability, tunable optical properties, good chemical stability, low biotoxicity, and biodegradability (generating orthosilicic acid that can be cleared by the kidneys). In recent years, they have attracted widespread attention in photocatalysis, biochemical analysis, and bioimaging. Furthermore, research on methods for directly synthesizing stable silicon quantum dots in the liquid phase (such as hydrothermal methods) has effectively improved the water solubility of silicon quantum dots. Researchers have developed methods for preparing silicon quantum dots emitting various colors of fluorescence by controlling the synthesis methods, reactants, and reaction conditions, with blue and green fluorescence being the most widely observed. Currently, most research focuses on the preparation of monochromatic fluorescent silicon quantum dots, while methods for synthesizing silicon quantum dots with dual emission properties are rarely reported.
[0003] Fluorescent probes based on monochromatic fluorescent silicon quantum dots primarily detect targets by utilizing changes in fluorescence intensity at a single emission wavelength. However, they are susceptible to interference from environmental factors such as probe concentration and excitation source fluctuations. In contrast, dual-emission silicon quantum dots possess two fluorescence emission peaks. As fluorescent probes, they can detect targets by utilizing changes in the ratio of the fluorescence intensities of the two signals, effectively eliminating interference from environmental factors and improving accuracy and sensitivity. In conclusion, the fabrication of dual-emission silicon quantum dots holds significant fundamental research value and broad application prospects in biochemical analysis and bioimaging. Summary of the Invention
[0004] Based on this, and in view of the shortcomings of existing silicon quantum dot technology, this application proposes a method for preparing and applying dual-emission silicon quantum dots to solve the technical bottleneck that there are few dual-emission wavelength fluorescent silicon quantum dots in the existing technology.
[0005] To achieve the above objectives, one of the technical solutions adopted by this invention is a method for preparing dual-emission silicon quantum dots. This preparation method includes:
[0006] Using 3-aminopropyltrimethoxysilane and orthocyanin as reaction precursors;
[0007] The reaction precursor was subjected to a one-step hydrothermal treatment to obtain silicon quantum dots;
[0008] The silicon quantum dots were subjected to dialysis and drying to obtain dual-emission silicon quantum dots.
[0009] This method for preparing dual-emission silicon quantum dots is simple to operate and the synthesis method is easy to implement.
[0010] Preferably, the preparation method further includes:
[0011] 1) Weigh out 3-aminopropyltrimethoxysilane and orthocyanin, dissolve them in deionized water, and mix well;
[0012] 2) Transfer the mixture obtained in step 1) to a stainless steel autoclave lined with polytetrafluoroethylene and heat at 160-200℃ for 4-12 hours.
[0013] 3) Fluorescent material is obtained when the autoclave is cooled to room temperature;
[0014] 4) Dialysis was performed using a dialysis membrane, and the resulting solution was dried to obtain dual-emission silicon quantum dots.
[0015] Preferably, the amounts of 3-aminopropyltrimethoxysilane, cinnamic acid, and deionized water added are 1 mL, 10-30 mg, and 5 mL, respectively.
[0016] Preferably, the dialysis membrane used has a molecular weight cutoff of 100-500 Da, and the drying is performed by baking or freeze drying.
[0017] A dual-emission fluorescent silicon quantum dot prepared by the aforementioned dual-emission silicon quantum dot preparation method.
[0018] The second technical solution of the present invention is an application of dual-emission silicon quantum dots in the field of cell imaging;
[0019] The dual-emission silicon quantum dots prepared by the method of this invention have low biotoxicity, can enter cells smoothly, and emit fluorescence, which can be used in the development of cell imaging.
[0020] This dual-emission silicon quantum dot exhibits dual-channel fluorescence in MC F-7 cells, showing potential applications in cell imaging.
[0021] Preferably, dual-emission silicon quantum dots are co-incubated with cells, and the cell imaging effect is detected using a fluorescence microscope.
[0022] More preferably, the cells are MCF-7 cells.
[0023] Compared with the prior art, the advantages of the present invention are:
[0024] 1. Dual-emission silicon quantum dots can be prepared in a single hydrothermal step. The synthesis method is simple, the raw materials are readily available, and the cost is low.
[0025] 2. Using the same excitation source, it has two fluorescence emission peaks in the blue and green light regions, which is a significant advantage compared with traditional monochromatic fluorescent silicon quantum dots, and can meet the needs of in vivo and in vitro bioimaging at the same time;
[0026] 3. The silicon quantum dots of the present invention have good stability and low biotoxicity, and have been successfully used in cell imaging, expanding the range of applicable fluorescent labeling material systems. Attached Figure Description
[0027] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0028] in:
[0029] Figure 1 The fluorescence spectrum of the dual-emission silicon quantum dot in Example 1 of this invention;
[0030] Figure 2 This is a transmission electron microscope image of the dual-emission silicon quantum dots in Embodiment 3 of the present invention;
[0031] Figure 3 This is the X-ray photoelectron spectrum of the dual-emission silicon quantum dot in Embodiment 3 of the present invention;
[0032] Figure 4 The fluorescence spectrum of the dual-emission silicon quantum dots in Example 3 of this invention;
[0033] Figure 5 This is a line graph showing the fluorescence intensity ratio of the dual-emission silicon quantum dots in Example 3 of the present invention as the pH changes from 5 to 9 at an excitation wavelength of 360 nm.
[0034] Figure 6 The fluorescence spectrum of the dual-emission silicon quantum dot in Example 5 of this invention;
[0035] Figure 7 This is a graph showing the cytotoxicity test results of the dual-emission silicon quantum dots in Example 3 of the present invention;
[0036] Figure 8 This is a cell imaging image of the dual-emission silicon quantum dots in Embodiment 3 of the present invention. Detailed Implementation
[0037] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Unless otherwise specified, the equipment and reagents used in each embodiment and experimental example can be obtained commercially. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0038] According to a typical embodiment of the present invention, a method for preparing dual-emission silicon quantum dots is provided.
[0039] Silicon quantum dots were prepared via a one-step hydrothermal method using 3-aminopropyltrimethoxysilane and oreganoic acid as precursors. The silicon quantum dots were then dialyzed and dried to obtain dual-emission fluorescent silicon quantum dots. Detailed explanation follows:
[0040] Example 1
[0041] This embodiment provides a method for preparing dual-emission silicon quantum dots, including the following steps:
[0042] 1) Weigh 1 mL of 3-aminopropyltrimethoxysilane and 20 mg of orthocyanin, dissolve them in 5 mL of water, and mix well;
[0043] 2) Transfer the mixture to a 25 mL PTFE-lined stainless steel high-pressure reactor and heat at 160 °C for 10 hours;
[0044] 3) The autoclave is cooled to room temperature to obtain the fluorescent material;
[0045] 4) Dialysis was performed using a dialysis membrane with a molecular weight cutoff of 100 Da. The resulting solution was then freeze-dried to obtain dual-emission silicon quantum dots.
[0046] See Figure 1 The fluorescence spectrum of the dual-emission silicon quantum dots prepared in Example 1 of this invention shows that the prepared dual-emission silicon quantum dots have maximum emission wavelengths of 440nm and 520nm respectively when the excitation wavelength is in the range of 300-400nm, and have clear dual emission wavelengths.
[0047] Example 2
[0048] This embodiment provides a method for preparing dual-emission silicon quantum dots, including the following steps:
[0049] 1) Weigh 1 mL of 3-aminopropyltrimethoxysilane and 10 mg of orthocyanin and dissolve them in 5 mL of water. Mix well.
[0050] 2) Transfer the mixture to a 25 mL PTFE-lined stainless steel high-pressure reactor and heat at 180 °C for 10 hours;
[0051] 3) The autoclave is cooled to room temperature to obtain the fluorescent material;
[0052] 4) Dialysis was performed using a dialysis membrane with a molecular weight cutoff of 200 Da. The resulting solution was then freeze-dried to obtain dual-emission silicon quantum dots.
[0053] Example 3
[0054] This embodiment provides a method for preparing dual-emission silicon quantum dots, including the following steps:
[0055] 1) Weigh 1 mL of 3-aminopropyltrimethoxysilane and 20 mg of orthocyanin and dissolve them in 5 mL of water. Mix well.
[0056] 2) Transfer the mixture to a 25 mL PTFE-lined stainless steel high-pressure reactor and heat at 180 °C for 10 hours;
[0057] 3) The autoclave is cooled to room temperature to obtain the fluorescent material;
[0058] 4) Dialysis was performed using a dialysis membrane with a molecular weight cutoff of 100 Da. The resulting solution was then freeze-dried to obtain dual-emission silicon quantum dots.
[0059] Figure 2 The image shows a transmission electron microscope (TEM) image of the dual-emission silicon quantum dots prepared in Example 3 of this invention. As can be seen from the image, the average diameter of the silicon quantum dots is 9.4 nm, and they are uniformly distributed.
[0060] Figure 3 The X-ray photoelectron spectroscopy characterization of the dual-emission silicon quantum dots prepared in this embodiment shows that the silicon quantum dots are composed of four elements: carbon (63.4%), oxygen (18.42%), nitrogen (6.96%), and silicon (11.22%).
[0061] Figure 4 The fluorescence spectrum of the dual-emission silicon quantum dots prepared in this embodiment is shown below. Figure 4 It can be seen that the dual-emission silicon quantum dot has two distinct emission peaks at 440nm and 520nm, while exhibiting almost no excitation dependence.
[0062] Figure 5 The graph shows the fluorescence intensity ratio of the dual-emission silicon quantum dots prepared in this embodiment as the pH changes from 5 to 9 at an excitation wavelength of 360 nm. As can be seen from the graph, the dual-emission silicon quantum dots are sensitive to pH.
[0063] Example 4
[0064] This embodiment provides a method for preparing dual-emission silicon quantum dots, including the following steps:
[0065] 1) Weigh 1 mL of 3-aminopropyltrimethoxysilane and 10 mg of orthocyanin and dissolve them in 5 mL of water. Mix well.
[0066] 2) Transfer the mixture to a 25 mL PTFE-lined stainless steel high-pressure reactor and heat at 200 °C for 10 hours;
[0067] 3) The autoclave is cooled to room temperature to obtain the fluorescent material;
[0068] 4) Dialysis was performed using a dialysis membrane with a molecular weight cutoff of 100 Da. The resulting solution was then freeze-dried to obtain dual-emission silicon quantum dots.
[0069] Example 5
[0070] This embodiment provides a method for preparing dual-emission silicon quantum dots, including the following steps:
[0071] 1) Weigh 1 mL of 3-aminopropyltrimethoxysilane and 20 mg of orthocyanin and dissolve them in 5 mL of water. Mix well.
[0072] 2) Transfer the mixture to a 25 mL PTFE-lined stainless steel high-pressure reactor and heat at 200 °C for 10 hours;
[0073] 3) The autoclave is cooled to room temperature to obtain the fluorescent material;
[0074] 4) Dialysis was performed using a dialysis membrane with a molecular weight cutoff of 100 Da. The resulting solution was then freeze-dried to obtain dual-emission silicon quantum dots.
[0075] Figure 6 The fluorescence spectrum of the dual-emission silicon quantum dots prepared in Example 5 of this invention is shown below. Figure 6 It can be seen that the prepared dual-emission silicon quantum dots have two obvious emission peaks at 440nm and 520nm, with clear dual emission wavelengths.
[0076] II. Specific embodiments of the application of the dual-emission fluorescent silicon quantum dots of the present invention.
[0077] Example 6
[0078] This embodiment demonstrates the application of dual-emission fluorescent silicon quantum dots in cell imaging. The dual-emission fluorescent silicon quantum dots prepared in Example 3 were used to test cell proliferation and toxicity. The specific implementation steps are as follows:
[0079] 1. Cell proliferation and toxicity test of dual-emission silicon quantum dots
[0080] MCF-7 cells were first cultured in 5 mL of DMEM medium containing 10% fetal bovine serum (FBS) at 37°C with 5% CO2 until the cells reached confluence. Then, the cells were seeded into 96-well plates (0.8 x 10⁻⁶ wells). 4 (Symptoms / well), after 12 hours, 100 μL of culture medium containing different concentrations of SiQDs (0.1, 0.2, ...) was added to each well.
[0081] Incubate the cells with 0.4, 0.6, 0.8, 1, 1.2, 1.5, and 2 mg / mL solutions for 24 hours. Finally, add 10 μL of CCK-8 solution and incubate for another 2 hours. Read the absorbance of each well at 450 nm using a microplate reader.
[0082] Depend on Figure 7 It can be seen that when different concentrations of silicon quantum dots are added, the cell survival rate remains above 95%, proving that the prepared dual-emission silicon quantum dots have low cytotoxicity and good biocompatibility.
[0083] 2. MCF-7 cell imaging
[0084] To evaluate the effect of SiQDs on cell imaging, MCF-7 cells were seeded in 20 mm glass-bottomed culture dishes and cultured at 37°C and 5% CO2. After 24 hours of incubation, the initial culture medium was removed, and 1 mL of fresh culture medium containing SiQDs (1 mg / mL) was added, followed by another 4 hours of incubation. The culture medium was then removed, and the cells were washed three times with PBS, fixed with 2% paraformaldehyde, and washed three times with PBS. Cell imaging was performed using confocal fluorescence microscopy.
[0085] Depend on Figure 8 It can be seen that dual-emission silicon quantum dots exhibit blue and green dual-channel fluorescence in MCF-7 cells, proving that the preparation of dual-emission silicon quantum dots can effectively enter MCF-7 cells and can image MCF-7 cells.
[0086] In summary, the dual-emission silicon quantum dots prepared using the method of this invention exhibit two distinct emission peaks near 440 nm and 520 nm, with almost no excitation wavelength dependence. The prepared dual-emission silicon quantum dots show low cytotoxicity and high biocompatibility, allowing them to enter MCF-7 cells smoothly. Furthermore, due to their dual-emission properties, they enable interference-free and more accurate intracellular fluorescence imaging, showing broad application prospects in cell imaging and providing a novel fluorescent probe for cell fluorescence imaging.
Claims
1. A method for preparing a double-emission silicon quantum dot, characterized in that, The method comprises: taking 3-aminopropyltrimethoxysilane and rhodanic acid as reaction precursors, and obtaining double-emission silicon quantum dots through hydrothermal treatment, dialysis and drying treatment, the addition amounts of the 3-aminopropyltrimethoxysilane, the rhodanic acid and deionized water are 1 mL, 10-30 mg and 5 mL, the hydrothermal temperature is 160-200 DEG C, the reaction time is 4-12 hours, the molecular weight cut-off of the dialysis membrane is 100-500 Da, the drying is baking or freeze drying, the maximum emission wavelengths of the silicon quantum dots under an excitation wavelength of 300-400 nm are 440 nm and 520 nm respectively, and the silicon quantum dots have pH responsiveness.
2. A double-emitter silicon quantum dot, characterized by: The pH-sensitive double-emission silicon quantum dots are prepared by using the preparation method of the double-emission silicon quantum dots in claim 1.
3. Application of the double-emission silicon quantum dots in claim 2 to the field of cell imaging.
4. Use according to claim 3, wherein: The double-emission silicon quantum dots are incubated with cells, blue and green double-channel fluorescence signals are collected by using a fluorescence microscope, and ratio cell imaging effect is realized through the ratio of the fluorescence intensities of the two channels.