A kind of preparation method of the fluorescence aqueous two-phase based on carbon quantum dot
Technical field
The present invention relates to a kind of preparation of the carbon quantum dot with ionic liquid as presoma, and fluorescence aqueous two-phase is built, it is applied to while realizing medicine efficiently concentrating and high-sensitivity detection.
Background technology
Liquid-liquid extraction (LLE) is the isolation technics commonly used in chemical industry and analytical chemistry, is widely used in the separation, preparation and sample pre-treatments in the field such as biology, medicine, food.Traditional liquid-liquid extraction system is mainly the two-phase system that organic solvent and aqueous solution are formed.However, as organic solvent has the shortcomings that volatility, flammable and toxicity, with increasingly attention of the international community to environmental problem, the use of organic solvent receives different degrees of restriction.In recent years, used as a kind of new isolation technics, because of its small volume, disposal ability is strong for aqueous two-phase extraction (ATPE) technology, during do not use poisonous organic solvent so as to get more and more people's extensive concerning in Green Chemistry field.Aqueous two-phase system (ATPS) referred between some Organic substances, or between Organic substance and inorganic salt, forming mutual exclusive two-phase or multiphase system after appropriate concentration dissolving in water.The principle that ATPE is extracted to organic solvent is similar, material is in accordance with two alternate selectivity distribution, after material enters ATPS, due to the impact of electrostatic interaction, hydrophobic interaction and interfacial tension, make its it is upper and lower it is biphase in concentration it is different, so as to reach the purpose of extraction.
The distinctive skin effect of nano material, small-size effect, macro quanta tunnel effect and quantum confined effect so as to show the performance of uniqueness at aspects such as light, electricity, thermal and magnetic, machinery, mechanics, become the focus of material science research.Carbon quantum dot is the nearest a kind of emerging carbon nanomaterial for finding, general particle diameter is less than 10nm, but as the difference of synthetic method also has exception.This is a kind of fluorescent nano material with conventional semiconductors quantum dot with similar optical performance and nano-scale, its toxicity is low, good biocompatibility, be readily synthesized and functional modification, preparing raw material are easily obtained, preparation cost is cheap, reaction kit is common and preparation condition is gentle etc. be conventional semiconductors quantum dot it is incomparable.The features such as good isotropism of carbon quantum dot, ultra-fine dimension, synthetic method multiformity, makes it have and is widely applied value, and carbon quantum dot can be used as the substitute of other carbon nanomaterials (fullerene, nanometer diamond, CNT) in numerous applications.
From in terms of synthetic method angle, high-performance and multi-functional carbon quantum dot are further studied, mainly has the work of following several respects:(1) as far as possible from green non-poisonous, the carbon source presoma of low cost, streamline operation;(2) optical property of existing carbon quantum dot is improved, makes the technique that its appearance depressed area is able to fill and lead up or improve cladding synthesis increase surface light emitting group etc. by adding passivator;(3) more new carbon quantum dots are developed, including its fluorescence emission spectral limit is expanded as far as possible, prepares that quantum yield is higher, the more preferable carbon quantum dot of light stability.
From in terms of synthetic raw material angle, ionic liquid has good physical and chemical stability, almost no vapour pressure,
Pollution problem of the volatile organic solvent to environment is eliminated, is the ideal substitute of traditional volatile organic solvent, is had broad application prospects.
This patent proposes to prepare carbon quantum dot with phosphorus pentoxide reaction as presoma using ionic liquid, and to its fluorescent characteristic and form aqueous two-phase and carry out systematic study into phase condition, then the fluorescence aqueous two-phase system of foundation is applied to while realizing the efficient fast enriching and high-sensitivity detection of medicine.
The content of the invention
Technical problem:
The technical problem to be solved in the present invention is the shortcoming for traditional quantum dot, for example, synthetic material is all that noble metal or heavy metal, synthetic method be complicated, synthetic instrument costly etc., therefore selecting green solvent --- ionic liquid prepares carbon quantum dot by wet chemistry method as presoma and phosphorus pentoxide, preparation flow is simple, while have also obtained higher quantum yield and preferable light stability.It is then based on the carbon quantum dot and sets up fluorescence aqueous two-phase, the various factors of phase condition is affected into by integrated survey, finally obtains optimal fluorescence aqueous two-phase and be applied to the enrichment and detection of medicine.
Technical scheme:
1st, technical solution of the invention is:
A, phosphorus pentoxide wet chemistry method prepare carbon quantum dot:A certain amount of ionic liquid is added in a certain amount of distilled water, is stirred, mixed solution is put into into heating a period of time in the round-bottomed flask for have phosphorus pentoxide, solution is changed into yellow from colourless, is cooled to room temperature, obtains carbon quantum dot;
The foundation of b, fluorescence aqueous two-phase:The carbon quantum dot prepared in a certain amount of a is added in a certain amount of distilled water, a certain amount of sodium dihydrogen phosphate is added, is stood after low speed shaking a period of time under the conditions of uniform temperature, is obtained fluorescence aqueous two-phase.
2nd, preparation method according to claim 1, it is characterised in that:In step a, the amount of ionic liquid used is 0.08~0.4g, and the amount of phosphorus pentoxide is 1.0~10.0g, and the amount of distilled water is 1~10mL, and the response time is 1~10min.
3rd, preparation method according to claim 1, it is characterised in that:In step b, the amount of carbon quantum dot is 10~200 μ L, and the addition of distilled water is 1~10mL, and the amount of sodium dihydrogen phosphate is 0.4~4g, stands or the shaking time is 5~60min, be 0~50 DEG C into phase temperature.
4th, preparation method according to claim 1, it is characterised in that:In step a, ionic liquid is 1- butyl -3- methyl imidazolium tetrafluoroborates ([Bmim] BF4), 1- ethyl-3-methylimidazole trifluoromethyl sulfonic acids ([Emim] OTF), 1- hexyl -3- methylimidazole villaumites ([Hmim] Cl), 1- butyl-pyridinium tetrafluoroborates ([BPy] BF4), 1- dodecyl -3- Methylimidazole. bromide ([C12Mim] Br), 1- butyl -1- methyl piperidine villaumites ([BMPi] Cl), N- ethylpyridine tetrafluoroborates
([EPy]BF4), 1- cetyl -3- methyl imidazolium tetrafluoroborate ([C16mim]BF4)。
5th, application of the fluorescence aqueous two-phase of the invention in drug detection, be dissolved in using above-mentioned carbon quantum dot-quantitative distilled water is subsequently adding a certain amount of sodium dihydrogen phosphate and sets up fluorescence aqueous two-phase and the fluorescence aqueous two-phase is applied to the method for drug detection through the following steps that carrying out:At a certain temperature, in some 10mL color comparison tubes, sequentially add the carbon quantum dot of a certain amount of preparation, a certain amount of distilled water and a certain amount of sodium dihydrogen phosphate, the flavonoid medicine Quercetin of variable concentrations, scale is diluted to the B-R buffer solution of pH 2.0, then stand after low speed shaking a period of time, fluorescence intensity after the upper Quercetin solution that addition variable concentrations are determined under certain excitation wavelength (λ ex=370nm) of fluorescence aqueous two-phase is taken finally, the addition of Quercetin is characterized using fluorescent quenching degree finally so as to reach the purpose of detection Quercetin.
Description of the drawings
Fig. 1 is the synthetic route schematic diagram that phosphorus pentoxide wet chemistry method of the present invention prepares carbon quantum dot.
Fig. 2 is the infared spectrum of carbon quantum dot obtained in the present invention.
Fig. 3 is fluorescence aqueous two-phase phasor obtained in the present invention.
Fig. 4 is the upper and lower phase fluorescence intensity comparison diagram of fluorescence aqueous two-phase obtained in the present invention.
Fig. 5 is the upper phase fluorescence pattern measured after fluorescence aqueous two-phase and the Quercetin of variable concentrations prepared by the present invention is acted on, λ ex=370nm;The volume of carbon quantum dot is 120 μ L;Distilled water volume is 5mL;B-R buffer solution is 4mL;Sodium dihydrogen phosphate is 0.95g;The concentration of Quercetin:10-9, 10-8, 10-7, 5 × 10-6, 10-6, 7 × 10-5, 10-5, 6 × 10-4, 10-4, 10-3mol L-1。
Specific embodiment
Prepare example
Following examples are some citings of the present invention, should not be seen as limitation of the invention.
Embodiment 1
A, phosphorus pentoxide wet chemistry method prepare carbon quantum dot:By 0.08g 1- butyl -3- methyl imidazolium tetrafluoroborates ([Bmim] BF4) add 4mL distilled water in, stir, mixed solution be put in having the round-bottomed flask of 5g phosphorus pentoxides and heat 5min, solution is changed into yellow from colourless, is cooled to room temperature, obtains carbon quantum dot;
The application of the fluorescence aqueous two-phase in drug detection of b, the present invention, is dissolved in 5mL amount distilled water using above-mentioned 120 μ L carbon quantum dots and is subsequently adding the sodium dihydrogen phosphate of 1.5g and set up fluorescence aqueous two-phase and the fluorescence aqueous two-phase is applied to the method for drug detection through the following steps that carrying out:At room temperature, in some 10mL color comparison tubes, sequentially add carbon quantum dot, 5mL distilled water and the 1.5g sodium dihydrogen phosphate of 120 μ L preparations, the flavonoid medicine Quercetin of variable concentrations, scale is diluted to the B-R buffer solution of pH 2.0, then low speed stands 10min after the shaking 30min times, finally takes the upper fluorescence intensity that the flavonoid medicine Quercetin for adding variable concentrations is determined under certain excitation wavelength (λ ex=370nm) of fluorescence aqueous two-phase.
Embodiment 2
A, phosphorus pentoxide wet chemistry method prepare carbon quantum dot:0.40g 1- ethyl-3-methylimidazole trifluoromethyl sulfonic acids ([Emim] OTF) are added in 6mL distilled water, stir, mixed solution is put in having the round-bottomed flask of 4.5g phosphorus pentoxides and heats 6min, solution is changed into yellow from colourless, room temperature is cooled to, carbon quantum dot is obtained;
The application of the fluorescence aqueous two-phase in drug detection of b, the present invention, is dissolved in 4mL amount distilled water using above-mentioned 180 μ L carbon quantum dots and is subsequently adding the sodium dihydrogen phosphate of 3.6g and set up fluorescence aqueous two-phase and the fluorescence aqueous two-phase is applied to the method for drug detection through the following steps that carrying out:At room temperature, in some 10mL color comparison tubes, sequentially add carbon quantum dot, 4mL distilled water and the 3.6g sodium dihydrogen phosphate of 180 μ L preparations, the flavonoid medicine Quercetin of variable concentrations, scale is diluted to the B-R buffer solution of pH 2.0, then low speed stands 20min after the shaking 40min times, finally takes the upper fluorescence intensity that the flavonoid medicine Quercetin for adding variable concentrations is determined under certain excitation wavelength (λ ex=370nm) of fluorescence aqueous two-phase.
Embodiment 3
A, phosphorus pentoxide wet chemistry method prepare carbon quantum dot:0.30g 1- hexyl -3- methylimidazole villaumites ([Hmim] Cl) is added in 1mL distilled water, stir, mixed solution is put in having the round-bottomed flask of 5.5g phosphorus pentoxides and heats 5min, solution is changed into yellow from colourless, room temperature is cooled to, carbon quantum dot is obtained;
The application of the fluorescence aqueous two-phase in drug detection of b, the present invention, is dissolved in 8mL amount distilled water using above-mentioned 140 μ L carbon quantum dots and is subsequently adding the sodium dihydrogen phosphate of 3.8g and set up fluorescence aqueous two-phase and the fluorescence aqueous two-phase is applied to the method for drug detection through the following steps that carrying out:At room temperature, in some 10mL color comparison tubes, sequentially add carbon quantum dot, 8mL distilled water and the 3.8g sodium dihydrogen phosphate of 140 μ L preparations, the flavonoid medicine Quercetin of variable concentrations, scale is diluted to the B-R buffer solution of pH 2.0, then low speed stands 30min after the shaking 30min times, finally takes the upper fluorescence intensity that the flavonoid medicine Quercetin for adding variable concentrations is determined under certain excitation wavelength (λ ex=370nm) of fluorescence aqueous two-phase.
Embodiment 4
A, phosphorus pentoxide wet chemistry method prepare carbon quantum dot:0.25g 1- butyl-pyridinium tetrafluoroborates ([BPy] BF4) are added in 3mL distilled water, stir, mixed solution is put in having the round-bottomed flask of 4.5g phosphorus pentoxides and heats 2min, solution is changed into yellow from colourless, room temperature is cooled to, carbon quantum dot is obtained;
The application of the fluorescence aqueous two-phase in drug detection of b, the present invention, is dissolved in 6mL amount distilled water using above-mentioned 100 μ L carbon quantum dots and is subsequently adding the sodium dihydrogen phosphate of 4.6g and set up fluorescence aqueous two-phase and the fluorescence aqueous two-phase is applied to the method for drug detection through the following steps that carrying out:At room temperature, in some 10mL color comparison tubes, sequentially add carbon quantum dot, 6mL distilled water and the 4.6g sodium dihydrogen phosphate of 100 μ L preparations, the flavonoid medicine Quercetin of variable concentrations, scale is diluted to the B-R buffer solution of pH 2.0, then low speed stands 10min after the shaking 50min times, finally takes the upper fluorescence intensity that the flavonoid medicine Quercetin for adding variable concentrations is determined under certain excitation wavelength (λ ex=370nm) of fluorescence aqueous two-phase.
Embodiment 5
A, phosphorus pentoxide wet chemistry method prepare carbon quantum dot:By 0.35g 1- dodecyl -3- Methylimidazole. bromide ([C12Mim] Br) add 4mL distilled water in, stir, mixed solution be put in having the round-bottomed flask of 3.5g phosphorus pentoxides and heat 4min, solution is changed into yellow from colourless, is cooled to room temperature, obtains carbon quantum dot;
The application of the fluorescence aqueous two-phase in drug detection of b, the present invention, is dissolved in 6mL amount distilled water using above-mentioned 190 μ L carbon quantum dots and is subsequently adding the sodium dihydrogen phosphate of 5.9g and set up fluorescence aqueous two-phase and the fluorescence aqueous two-phase is applied to the method for drug detection through the following steps that carrying out:At room temperature, in some 10mL color comparison tubes, sequentially add carbon quantum dot, 6mL distilled water and the 5.9g sodium dihydrogen phosphate of 190 μ L preparations, the flavonoid medicine Quercetin of variable concentrations, scale is diluted to the B-R buffer solution of pH 2.0, then low speed stands 40min after the shaking 30min times, finally takes the upper fluorescence intensity that the flavonoid medicine Quercetin for adding variable concentrations is determined under certain excitation wavelength (λ ex=370nm) of fluorescence aqueous two-phase.
Embodiment 6
A, phosphorus pentoxide wet chemistry method prepare carbon quantum dot:0.38g 1- butyl -1- methyl piperidine villaumites ([BMPi] Cl) is added in 5mL distilled water, stir, mixed solution is put in having the round-bottomed flask of 5.5g phosphorus pentoxides and heats 6min, solution is changed into yellow from colourless, room temperature is cooled to, carbon quantum dot is obtained;
The application of the fluorescence aqueous two-phase in drug detection of b, the present invention, is dissolved in 5mL amount distilled water using above-mentioned 180 μ L carbon quantum dots and is subsequently adding the sodium dihydrogen phosphate of 6.9g and set up fluorescence aqueous two-phase and the fluorescence aqueous two-phase is applied to the method for drug detection through the following steps that carrying out:At room temperature, in some 10mL color comparison tubes, sequentially add carbon quantum dot, 5mL distilled water and the 6.9g sodium dihydrogen phosphate of 180 μ L preparations, the flavonoid medicine Quercetin of variable concentrations, scale is diluted to the B-R buffer solution of pH 2.0, then low speed stands 40min after the shaking 20min times, finally takes the upper fluorescence intensity that the flavonoid medicine Quercetin for adding variable concentrations is determined under certain excitation wavelength (λ ex=370nm) of fluorescence aqueous two-phase.
Embodiment 7
A, phosphorus pentoxide wet chemistry method prepare carbon quantum dot:By 0.30g N- ethylpyridine tetrafluoroborates ([EPy] BF4) add 4mL distilled water in, stir, mixed solution be put in having the round-bottomed flask of 6.5g phosphorus pentoxides and heat 6min, solution is changed into yellow from colourless, is cooled to room temperature, obtains carbon quantum dot;
The application of the fluorescence aqueous two-phase in drug detection of b, the present invention, is dissolved in 6mL amount distilled water using above-mentioned 150 μ L carbon quantum dots and is subsequently adding the sodium dihydrogen phosphate of 5.7g and set up fluorescence aqueous two-phase and the fluorescence aqueous two-phase is applied to the method for drug detection through the following steps that carrying out:At room temperature, in some 10mL color comparison tubes, sequentially add carbon quantum dot, 6mL distilled water and the 5.7g sodium dihydrogen phosphate of 150 μ L preparations, the flavonoid medicine Quercetin of variable concentrations, scale is diluted to the B-R buffer solution of pH 2.0, then low speed stands 5min after the shaking 50min times, finally takes the upper fluorescence intensity that the flavonoid medicine Quercetin for adding variable concentrations is determined under certain excitation wavelength (λ ex=370nm) of fluorescence aqueous two-phase.
Embodiment 8
A, phosphorus pentoxide wet chemistry method prepare carbon quantum dot:By 0.40g 1- cetyl -3- methyl imidazolium tetrafluoroborate ([C16mim]BF4) add 5mL distilled water in, stir, mixed solution be put in having the round-bottomed flask of 3.5g phosphorus pentoxides and heat 3min, solution is changed into yellow from colourless, is cooled to room temperature, obtains carbon quantum dot;
The application of the fluorescence aqueous two-phase in drug detection of b, the present invention, is dissolved in 5mL amount distilled water using above-mentioned 120 μ L carbon quantum dots and is subsequently adding the sodium dihydrogen phosphate of 5.8g and set up fluorescence aqueous two-phase and the fluorescence aqueous two-phase is applied to the method for drug detection through the following steps that carrying out:At room temperature, in some 10mL color comparison tubes, sequentially add carbon quantum dot, 5mL distilled water and the 5.8g sodium dihydrogen phosphate of 120 μ L preparations, the flavonoid medicine Quercetin of variable concentrations, scale is diluted to the B-R buffer solution of pH 2.0, then low speed stands 30min after the shaking 40min times, finally takes the upper fluorescence intensity that the flavonoid medicine Quercetin for adding variable concentrations is determined under certain excitation wavelength (λ ex=370nm) of fluorescence aqueous two-phase.