CN110824030A - Method for extracting pesticide from curcuma wenyujin - Google Patents
Method for extracting pesticide from curcuma wenyujin Download PDFInfo
- Publication number
- CN110824030A CN110824030A CN201910796496.0A CN201910796496A CN110824030A CN 110824030 A CN110824030 A CN 110824030A CN 201910796496 A CN201910796496 A CN 201910796496A CN 110824030 A CN110824030 A CN 110824030A
- Authority
- CN
- China
- Prior art keywords
- eutectic solvent
- graphene
- curcuma wenyujin
- pesticide
- curcuma
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N30/00—Investigating or analysing materials by separation into components using adsorption, absorption or similar phenomena or using ion-exchange, e.g. chromatography or field flow fractionation
- G01N30/02—Column chromatography
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N30/00—Investigating or analysing materials by separation into components using adsorption, absorption or similar phenomena or using ion-exchange, e.g. chromatography or field flow fractionation
- G01N30/02—Column chromatography
- G01N30/04—Preparation or injection of sample to be analysed
- G01N30/06—Preparation
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N30/00—Investigating or analysing materials by separation into components using adsorption, absorption or similar phenomena or using ion-exchange, e.g. chromatography or field flow fractionation
- G01N30/02—Column chromatography
- G01N30/04—Preparation or injection of sample to be analysed
- G01N30/06—Preparation
- G01N2030/062—Preparation extracting sample from raw material
Landscapes
- Physics & Mathematics (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Carbon And Carbon Compounds (AREA)
Abstract
The invention relates to the field of pharmaceutical analysis, and discloses a method for extracting pesticides from curcuma wenyujin, which comprises the following steps: pretreating Curcuma wenyujin medicinal material to obtain Curcuma wenyujin test solution; preparing a eutectic solvent; preparing the eutectic solvent functionalized graphene by using the prepared eutectic solvent; carrying out dispersive micro-solid phase extraction on the curcuma wenyujin test solution by taking the eutectic solvent functionalized graphene as an adsorbent, centrifuging, filtering eluent, and carrying out sample analysis to represent the pesticide enrichment effect. According to the invention, the eutectic solvent functionalized graphene is used as an adsorbent, is used for an enrichment technology of dispersive micro-solid phase extraction, and is applied to the fields of enrichment and detection of pesticide residues in traditional Chinese medicinal materials, and the eutectic solvent has the advantages of low melting point, low toxicity, easiness in synthesis and easiness in biodegradation; the graphene has a large surface area, is easy to adsorb and desorb various compounds, and has good dispersibility and stability in an aqueous solution, and the reliability of the method is guaranteed.
Description
Technical Field
The invention relates to the field of drug analysis, in particular to a method for extracting pesticides from curcuma wenyujin.
Background
Curcuma wenyujin (Curcuma wenyujin) is a plant of Curcuma of Zingiberaceae, the root tuber and rhizome of Curcuma wenyujin are used as medicines, the Curcuma wenyujin processed from root tuber is one of the famous and famous medicinal materials of Zhejiang province, Zhe Ba Wei, and has the efficacies of anti-tumor, anti-virus and anti-thrombus, etc., and the market value is very high. In recent years, with the increase of the demand of traditional Chinese medicines, wild traditional Chinese medicine resources are gradually lacked, and artificial planting has become the mainstream of traditional Chinese medicine sources. The large-scale planting of Chinese medicinal materials can not avoid plant diseases and insect pests, and pesticides such as organochlorine pesticides, organophosphorus pesticides and pyrethroid pesticides are widely applied. However, airborne pesticides can accumulate on the surface of crops and flow into the food chain, causing serious damage to other species. Especially, pyrethroid insecticides are more toxic to mammals due to low water solubility, high lipid solubility, easy passage through biological membranes. Therefore, it is necessary to detect the pesticide content in the traditional Chinese medicine.
However, it is often difficult to directly measure target analytes in complex sample matrices, and the amount of pesticide residues is low and not easily detectable, so sample pretreatment and enrichment are essential to extract target compounds from various complex samples and to improve their detection sensitivity. In recent years, solid phase extraction, acetonitrile extraction, homogeneous liquid-liquid microextraction, and the like have been used for extracting pyrethroid pesticides in complex matrices. For example, the publication "a membrane extraction method of pyrethroid pesticide residue in a complex sample" in the Chinese patent literature, the publication No. CN104297043B, includes the following steps: placing a low-density polyethylene film bag with the surface grafted with the molecularly imprinted material in a normal hexane solution for pretreatment; adding a proper amount of acetonitrile into a sample to be detected: homogenizing with water (1: 9, v/v), centrifuging, and placing appropriate amount of supernatant into a headspace sampling bottle; further placing the pretreated membrane bag into a headspace sample injection bottle, adding an extraction solvent, and carrying out treatments such as oscillation and the like to obtain an extraction solution; the method has the advantages that the method can be applied to separation, purification and enrichment of pyrethroid pesticide residues in complex biological samples, has higher separation and purification capacity, and has higher separation and purification efficiency compared with conventional liquid-liquid extraction and solid-phase extraction.
However, these methods have disadvantages such as low sensitivity, large consumption of organic solvents, and cumbersome process. Therefore, it is necessary to develop a simple, green and highly sensitive pre-concentration extraction method for detecting pesticides in complex matrix.
Disclosure of Invention
The invention aims to overcome the defects of low sensitivity, large consumption of organic solvent, complicated method and the like of the existing detection method of pesticide in complex matrix and is not beneficial to practical application, and provides a method for extracting pesticide in curcuma wenyujin, which can stably, reliably, quickly and sensitively extract and detect pesticide components in traditional Chinese medicinal materials by using the interaction of eutectic solvent and graphene powder as an adsorbent in a dispersive micro solid phase extraction technology, has low consumption of organic solvent, does not need large-scale instruments for assistance, and has simple sample pretreatment operation.
In order to achieve the purpose, the invention adopts the following technical scheme:
a method for extracting pesticides from Curcuma wenyujin comprises the following steps:
(1) pretreating Curcuma wenyujin medicinal material to obtain Curcuma wenyujin test solution;
(2) preparing a eutectic solvent: the eutectic solvent is choline chloride in a molar ratio of: propylene glycol: 1:1:1, choline chloride: glycerol ═ 1:2, choline chloride: urea 1:2, betaine: glycerol ═ 1:2, betaine: glycerol: propylene glycol 1:1:1, wherein choline chloride and betaine are hydrogen bond acceptors, and the other reagents are hydrogen bond donors;
(3) preparing the eutectic solvent functionalized graphene by using the prepared eutectic solvent;
(4) carrying out dispersive micro-solid phase extraction on the curcuma wenyujin test solution by taking the eutectic solvent functionalized graphene as an adsorbent, centrifuging, filtering eluent, and carrying out sample analysis to represent the pesticide enrichment effect.
The method takes the eutectic solvent functionalized graphene as an adsorbent, and adopts a dispersive micro-solid phase extraction method to extract the pesticide to be analyzed from the curcuma wenyujin medicinal material. The dispersive micro-solid phase extraction is an extraction method based on the adsorption of a compound on an adsorbent and the desorption of a target analyte by an eluent under the mu L level, and the method is adopted to enrich the pesticide in the curcuma wenyujin medicinal material, has good enrichment effect, can greatly improve the detection sensitivity, has low consumption of organic solvent, does not need large-scale instruments for assistance, and has simple sample pretreatment operation.
The core of the dispersive micro-solid phase extraction is the selection of an adsorbent, the invention prepares the eutectic solvent functionalized graphene as the adsorbent, the graphene is a novel carbon nano material and comprises a two-dimensional single-layer carbon sheet structure formed by stacking hexagonal honeycomb lattices, and the graphene is easy to adsorb and desorb NO-containing carbon sheets2，NH3，K+And OH-The compound has large surface area, is easy to synthesize clean materials, and is used as an adsorbent. However, the main disadvantage of the tendency of graphene to agglomerate leads to its instability in the aqueous phase and limits its wider application. The tendency of easy agglomeration is caused by the influence of pi-conjugation and van der waals force in the microstructure of graphene, so that functional modification of graphene is required to improve the problem of easy agglomeration.
The eutectic solvent is a two-or three-component eutectic mixture consisting of a hydrogen bond acceptor and a hydrogen bond donor in a suitable stoichiometric ratio, choline chloride and betaine are commonly used as the hydrogen bond acceptor of the eutectic solvent, and urea, polyol and sugar are commonly used as the hydrogen bond donor. The eutectic solvent has low melting point, low toxicity, easy synthesis and easy biodegradation, and graphene obtained by functional modification of the eutectic solvent has good dispersibility and stability in aqueous solution, has good adsorbability on residual pesticide in Curcuma wenyujin medicinal materials, and can realize effective enrichment on pesticide by the adsorbent used in dispersive micro-solid phase extraction.
Preferably, the preparation method of the medium-temperature curcuma aromatica test solution in the step (1) comprises the following steps:
A) pulverizing radix Curcumae and sieving to obtain medicinal powder;
B) adding the medicinal powder into the medicinal powder in a ratio of (5-6) mL: 1g of 1% glacial acetic acid solution until the medicinal material powder is completely soaked, standing, adding acetonitrile with the same volume as the glacial acetic acid, and uniformly mixing by oscillation;
C) adding the raw materials in a mass ratio of (2-3): 1, wherein the mass ratio of the anhydrous magnesium sulfate to the anhydrous sodium sulfate is 4: 1;
D) and oscillating uniformly, cooling in an ice bath, performing centrifugal separation, taking supernatant, placing the supernatant into a centrifugal tube filled with a purifying material, oscillating, purifying, performing centrifugal separation, and diluting the supernatant to obtain the curcuma wenyujin test solution.
By adopting the method, acetonitrile is taken as an extraction solvent, so that the effective components in the curcuma wenyujin medicinal material can be successfully extracted to prepare the curcuma wenyujin medicinal material extracting solution, and solid-phase extraction small columns are used for removing impurities to obtain the curcuma wenyujin test solution.
Preferably, the purifying material in the step D) and the dosage in the centrifuge tube are as follows: 900mg/50mL of anhydrous magnesium sulfate, 300mg/50mL of N-propylethylenediamine, C18300mg/50mL, 300mg/50mL silica gel, 90mg/50mL graphitized carbon black. By adopting the purification material and the dosage, impurities in the curcuma wenyujin extracting solution can be effectively removed, and the influence on subsequent enrichment and determination results is avoided.
Preferably, the preparation method of the low eutectic solvent in the step (2) comprises the following steps: and drying the hydrogen bond acceptor, mixing the hydrogen bond acceptor and the hydrogen bond donor in proportion, stirring and heating at 60-80 ℃ until the mixture becomes uniform transparent liquid, and cooling to room temperature to obtain the eutectic solvent. Because choline chloride and betaine which are used as hydrogen bond acceptors have hygroscopicity, the eutectic solvent can be obtained by drying before use, mixing with a hydrogen bond donor and heating.
Preferably, the preparation method of the low eutectic solvent functionalized graphene in the step (3) comprises the following steps: weighing (3-4) mL in proportion: and mixing and uniformly stirring 100mg of eutectic solvent and graphene, sealing, performing ultrasonic treatment at 55-65 ℃ for 2-4 hours, and then performing vacuum drying at 90-110 ℃ to obtain the eutectic solvent functionalized graphene. By adopting the method, the eutectic solvent can effectively react with the graphene, the graphene is modified, the van der Waals force of graphene molecules is changed, and the problem that the graphene is easy to agglomerate is solved.
Preferably, the graphene is any one of single-layer graphene oxide, aminated graphene and carboxylated graphene. These graphene species can effectively react with the eutectic solvent, improve the problem of agglomeration, and have a good adsorption effect when used as an adsorbent in dispersed micro-solid phase extraction.
Preferably, the method for dispersive micro-solid phase extraction in the step (4) comprises the following steps: mixing the curcuma wenyujin test solution and the eutectic solvent functionalized graphene, filtering the mixed solution after oscillation adsorption, eluting with an organic solvent, centrifugally separating the eluent, and taking the supernatant for UHPLC analysis. The Curcuma wenyujin test solution is subjected to dispersive micro solid phase extraction by using the eutectic solvent functionalized graphene as an adsorbent, so that the pesticide in the Curcuma wenyujin test solution can be effectively enriched.
Preferably, the organic solvent is any one of methanol, acetonitrile, ethyl acetate, chloroform, petroleum ether, and acetone. And a proper organic solvent is used as an eluent, so that the component to be detected can be effectively eluted, and the aim of enrichment is fulfilled.
Preferably, the oscillating adsorption time in the dispersed micro solid phase extraction in the step (4) is 1.0 to 2.5 min. By adopting the oscillation time in the invention, the effective enrichment of pesticide can be realized, the oscillation time is too short, the target analyte cannot be effectively adsorbed, the oscillation time is too long, the interaction between the analyte and graphene is too strong, and the analyte is difficult to be eluted by the eluent, thereby causing the loss and the response reduction of the analyte.
Preferably, a 0.22 μm filter is used for the filtration in step (4). The filter membrane with the pore size can effectively retain the eutectic solvent functionalized graphene.
Therefore, the invention has the following beneficial effects:
(1) the method adopts the eutectic solvent functionalized graphene as an adsorbent, is used for an enrichment technology of dispersive micro-solid phase extraction, and is applied to the field of enrichment and detection of pesticide residues in the traditional Chinese medicinal materials, and the adopted eutectic solvent is a new green solvent, has low melting point and toxicity, is easy to synthesize and biodegrade; the graphene is a novel carbon nano material, has large surface area, is easy to adsorb and desorb various compounds, and has good dispersibility and stability in an aqueous solution, so that the reliability of the method is guaranteed;
(2) after being treated by a dispersive micro solid phase extraction enrichment method, the detection sensitivity is greatly improved, and the enrichment multiple of the pyrethroid pesticide in the method is as high as 46-59 times;
(3) the experimental enrichment effect provided by the invention is high-efficiency and obvious, the operation steps are simple and clear, the operation environment is safe, few organic reagents are used, and the environment is not polluted.
Drawings
Fig. 1 is an infrared spectrum of a eutectic solvent, graphene and functionalized graphene; in the figure: DES refers to the prepared eutectic solvent, G refers to graphene, DES-G refers to the eutectic solvent functionalized graphene;
fig. 2 is a scanning and transmission electron microscope image of a eutectic solvent, graphene and functionalized graphene; in the figure: a is a scanning electron microscope image of single-layer graphene oxide (a1), aminated graphene (b1), carboxylated graphene (c1), eutectic solvent functional single-layer graphene oxide (a2), eutectic solvent functional aminated graphene (b2) and eutectic solvent functional carboxylated graphene (c 2); b is a transmission electron microscope image of single-layer graphene oxide (a3), aminated graphene (B3), carboxylated graphene (c3), eutectic solvent functional single-layer graphene oxide (a4), eutectic solvent functional aminated graphene (B4) and eutectic solvent functional carboxylated graphene (c 4);
FIG. 3 shows the dispersion of different types of eutectic solvent functionalized graphene in distilled water;
FIG. 4 is a bar graph of the enrichment effect of different types of eutectic solvent types on single-layer graphene oxide;
FIG. 5 shows the dispersion of different kinds of graphene functionalized by the same eutectic solvent in distilled water; in the figure: 1 single-layer graphene oxide, 2 aminated graphene and 3 carboxylated graphene;
FIG. 6 is a bar graph of the enrichment effect of different kinds of graphene treated by the same eutectic solvent; in the figure: monolayer GO, rGO-TEPA and GO-COOH respectively represent single-layer graphene oxide, aminated graphene and carboxylated graphene which are processed by DES 5;
fig. 7 is a line graph of enrichment effect for different functionalized graphene concentrations;
FIG. 8 is a graph of enrichment effect curves for different oscillation times;
FIG. 9 is a bar graph of the enrichment effect of different elution solvent species;
FIG. 10 is a liquid chromatogram of Curcuma wenyujin Y.H.Chen et C.Ling extract; in the figure: a. turmeric root tuber extract, b, turmeric root tuber extract plus standard 0.05 mu g/mL, c, turmeric root tuber extract plus standard 0.5 mu g/mL.
In fig. 4 and fig. 6-10: 1. fenpropathrin; 2. ethofenprox; 3. bifenthrin; 4. fenvalerate; 5. cyhalothrin.
Detailed Description
The invention is further described with reference to the following detailed description and accompanying drawings.
The eutectic solvent functionalized graphene provided by the invention is prepared by the following method: drying choline chloride and betaine at 60 deg.C under vacuum for 6 hr before use, mixing choline chloride or betaine and hydrogen bond donor at a certain proportion, adding the mixture into a clean beaker, heating on a heating plate at 70 deg.C at 300r until the mixture becomes uniform transparent liquid, and cooling to room temperature to obtain eutectic solvent. Respectively weighing 7mL of newly prepared eutectic solvent and 200mg of graphene, placing the mixture in a beaker, fully stirring the mixture until the eutectic solvent and the graphene are completely and uniformly mixed, sealing, carrying out ultrasonic treatment at 60 ℃ for 3 hours, and then carrying out vacuum drying at 100 ℃ for 3 hours to obtain the eutectic solvent functionalized graphene. An appropriate amount of functionalized graphene was weighed and diluted with water to prepare a stock solution of 1000 μ g/mL, which was diluted with water to obtain a graphene dispersion of the desired concentration before use.
The pesticide sample solution is prepared by the following method: taking 1mg of fenpropathrin, ethofenprox, bifenthrin, fenvalerate and lambda-cyhalothrin standard samples respectively, precisely weighing, and dissolving with methanol ultrasonic wave to prepare stock solutions of 1000 mug/mL respectively. On the day of use, 10. mu.L of each of the 5 stock solutions was pipetted into a 1mL centrifuge tube, 950. mu.L of methanol was added, and 100. mu.g/mL of the mixture was mixed well and ready for use.
The UHPLC chromatographic conditions in the invention are as follows: a chromatographic column: agilent SB-C18(100mm × 2.1mm i.d., 1.8 μm), detection wavelength: 210nm, column temperature: 35 ℃, sample introduction: 2.0. mu.L, flow rate 0.4mL/min, mobile phase: a: water, B: and (3) acetonitrile. Gradient elution: 0-5 min, 70% -90% B; 5-7 min, 90-100% B.
Firstly, the influence of the eutectic solvent type on the enrichment effect is inspected:
1. taking 6 clean 100mL narrow-mouth transparent glass bottles with the numbers of DES1, DES2, DES3, DES4, DES5 and DES6, respectively adding corresponding hydrogen bond acceptors and hydrogen bond donors according to a certain molar ratio according to the table 1, fully mixing uniformly, adding magnetons, heating on a heating plate at 70 ℃, rotating at 300r until the mixture becomes uniform transparent liquid, and cooling to room temperature to obtain the eutectic solvent.
Table 1: and (4) eutectic solvent formula.
2. Taking 5 clean 50mL beakers, numbering 1, 2, 3, 4 and 5, weighing 7mL of 5 newly prepared eutectic solvents (DES1 is solidified after cooling and discarded) in sequence, placing the 5 newly prepared eutectic solvents in the beakers, respectively adding 200mg of single-layer graphene oxide, fully stirring the mixture until the eutectic solvents and the graphene are completely and uniformly mixed, sealing, performing ultrasonic treatment at 60 ℃ for 3 hours, and then performing vacuum drying at 100 ℃ for 3 hours to obtain the 5 eutectic solvent functionalized graphene.
3. And taking 5 clean 100mL narrow-mouth transparent glass bottles with numbers Gr1, Gr2, Gr3, Gr4 and Gr5, weighing a proper amount of eutectic solvent functionalized graphene, diluting with water to prepare a stock solution of 1000 mu g/mL, standing, and observing the dispersion condition of the eutectic solvent functionalized graphene. On the day of use, the stock solution was diluted with water to make 100. mu.g/mL of graphene dispersion.
4. 50. mu.L of 100. mu.g/mL pesticide sample solution and 4950. mu.L of ultrapure water were placed in a 15mL centrifuge tube, and 2.5. mu.g/mL graphene (Gr4, Gr5) dispersion was added. Shaking at 500r for 2 minutes to allow sufficient adsorption of the target analyte to the eutectic solvent functionalized graphene. The mixed solution was filtered through a 0.22 μm disposable nylon filter, 100 μ L of methanol was aspirated and injected into a filter head, the target analyte was eluted by applying pressure manually, and 13000r eluate was centrifuged for 5 minutes, and the sample was loaded and subjected to UHPLC analysis.
The results are shown in FIGS. 3 and 4. As can be seen from fig. 3, the functionalized graphene with the eutectic solvent immediately after the ultrasonic treatment is uniformly dispersed in water. However, Gr1 and Gr2 aggregated only in 5 minutes, and Gr3 gradually aggregated in 10 minutes. After standing for 48 hours, Gr1, Gr2 and Gr3 were completely coagulated, and a clear water layer appeared. However, Gr4 and Gr5 exhibit long-term stability. The possible reason is that the hydrogen bond donor and hydrogen bond acceptor have different forces, the eutectic solvent-treated graphene prepared from different mixtures has different dispersibility, and the carboxyl functional group of betaine provides more oxygen atoms to form hydrogen bonds with the hydrogen bond acceptor. Therefore, the selection of the eutectic solvent treated Gr4 and Gr5 prepared from betaine was used to further investigate the enrichment effect of graphene treated with different eutectic solvent species. As can be seen from fig. 4, Gr4 has the best extraction efficiency. This result is attributed to the high solubility of water-insoluble graphene in the polyol-based eutectic solvent. Therefore, subsequent experiments selected DES5(Gr 4).
Secondly, investigating the influence of the graphene variety on the enrichment effect:
1. taking 3 clean 50mL beakers, numbering 1, 2 and 3, weighing 7mL DES5 prepared by the method in sequence, placing in the beakers, respectively adding 200mg of single-layer graphene oxide, aminated graphene and carboxylated graphene, and fully stirring the mixture until the eutectic solvent and the graphene are completely and uniformly mixed. Sealing, performing ultrasonic treatment at 60 ℃ for 3 hours, and then performing vacuum drying at 100 ℃ for 3 hours to obtain 3 types of eutectic solvent functionalized graphene.
2. Taking 3 clean 100mL narrow-mouth transparent glass bottles with numbers 1, 2 and 3, weighing a proper amount of eutectic solvent functionalized graphene, diluting with water to prepare a stock solution of 1000 mu g/mL, standing, and observing the dispersion condition of the eutectic solvent functionalization. On the day of use, the stock solution was diluted with water to make 100. mu.g/mL of graphene dispersion.
3. 50 mu L of pesticide sample solution with the concentration of 100 mu g/mL and 4950 mu L of ultrapure water are placed in a 15mL centrifuge tube, and 2.5 mu g/mL graphene (monolayer graphene oxide, aminated graphene and carboxylated graphene) dispersion liquid is added. Shaking at 500r for 2 minutes to allow sufficient adsorption of the target analyte to the eutectic solvent functionalized graphene. The mixed solution was filtered through a 0.22 μm disposable nylon filter, 100 μ L of methanol was aspirated and injected into a filter head, the target analyte was eluted by applying pressure manually, and 13000r eluate was centrifuged for 5 minutes, and the sample was loaded and subjected to UHPLC analysis.
As shown in fig. 5 and 6, it can be seen from fig. 6 that the aminated graphene treated with DES5 has the highest extraction efficiency for target analytes compared to the monolayer graphene oxide treated with DES5 and the carboxylated graphene, because the basal plane of the monolayer graphene oxide mainly contains oxygen-containing functional groups, changing the van der waals force of the graphite molecules and affecting their state in aqueous solution. However, as can be seen from fig. 5, the functionalized aminated graphene starts to agglomerate at 30 minutes and shows visible delamination at 60 minutes. This phenomenon may competitively inhibit the interaction of graphene with the eutectic solvent due to the formation of intramolecular hydrogen bonds in the aminated graphene, resulting in its instability in water. Therefore, a single layer of graphene oxide is selected in consideration of dispersion stability and extraction efficiency.
Thirdly, investigating the influence of the concentration of the functionalized graphene on the enrichment effect:
50 mu L of pesticide sample solution with the concentration of 100 mu g/mL and 4950 mu L of ultrapure water are put into a 15mL centrifuge tube, and the concentrations are as follows: 0.5, 1.5, 2.5, 3.5 μ g/mL graphene dispersion (eutectic solvents are betaine and glycerol in a molar ratio of 1:2, graphene is a monolayer of graphene oxide), was shaken at 500r for 2 minutes to allow sufficient adsorption of the target analyte to the eutectic solvent functionalized graphene. The mixed solution was filtered through a 0.22 μm disposable nylon filter, 100 μ L of methanol was aspirated and injected into a filter head, the target analyte was eluted by applying pressure manually, and 13000r eluate was centrifuged for 5 minutes, and the sample was loaded and subjected to UHPLC analysis.
As shown in FIG. 7, it can be seen that the peak areas of the five pesticides reached the highest peak area at a concentration of 1.5. mu.g/mL, and were significantly reduced when the concentration exceeded 1.5. mu.g/mL. The result is related to the adsorption saturation of the porous surface of graphene, and the high concentration of graphene provides a large surface area and a large number of adsorption sites for adsorbing a target analyte, thereby improving the enrichment efficiency. However, too high concentration of graphene generates strong adsorption capacity to the target compound, and is difficult to elute by the eluent, resulting in poor enrichment efficiency. Therefore, 1.5. mu.g/mL was selected as the optimum concentration.
Fourthly, investigating the influence of the oscillation time on the enrichment effect:
50 mu L of pesticide sample solution of 100 mu g/mL and 4950 mu L of ultrapure water are placed in a 15mL centrifuge tube, 1.5 mu g/mL of graphene dispersion liquid (eutectic solvent is betaine and glycerol with a molar ratio of 1:2, and graphene is single-layer graphene oxide) is added, and the mixture is respectively oscillated for 1, 1.5, 2 and 2.5min at 500r to enable the target analyte and the eutectic solvent functionalized graphene to be fully adsorbed. The mixed solution was filtered through a 0.22 μm disposable nylon filter, 100 μ L of methanol was aspirated and injected into a filter head, the target analyte was eluted by applying pressure manually, and 13000r eluate was centrifuged for 5 minutes, and the sample was loaded and subjected to UHPLC analysis.
The results are shown in fig. 8, from which it can be seen that the peak areas of the five pyrethroid insecticides increased to the maximum when the mixture was shaken for 1.5 minutes. Sufficient extraction time ensures that the target analyte is fully contacted with the surface of the graphene, and the adsorption efficiency of the graphene to the target analyte is improved. However, the peak area gradually decreased as the oscillation time increased from 1.5 minutes to 2.5 minutes. This is probably because the oscillation time is too long, the interaction between the analyte and graphene is stronger, and the analyte is difficult to elute by the eluent, resulting in loss of the analyte and a decrease in response. Therefore, 1.5 minutes was selected as the optimum time.
Fifthly, investigating the influence of the eluent type on the enrichment effect:
50 mu L of pesticide sample solution of 100 mu g/mL and 4950 mu L of ultrapure water are placed in a 15mL centrifuge tube, 1.5 mu g/mL of graphene dispersion liquid (eutectic solvent is betaine and glycerol with a molar ratio of 1:2, and graphene is single-layer graphene oxide) is added, and the mixture is respectively oscillated for 1.5min at 500r to enable the target analyte and the eutectic solvent functionalized graphene to be fully adsorbed. Filtering the mixed solution with 0.22 μm disposable nylon filter, respectively sucking 100 μ L methanol, acetonitrile, ethyl acetate, chloroform, petroleum ether, and acetone, pumping into filter head, manually pressurizing to elute target analyte, centrifuging the eluate for 13000r for 5min, loading, and performing UHPLC analysis.
As a result, as shown in fig. 9, it can be observed that acetonitrile has the best elution effect on five pyrethroid pesticides, followed by acetone, ethyl acetate and methanol, whereas chloroform and petroleum ether give eluents with very poor and almost undetectable response to the pesticides. This phenomenon may be due to the strong elution ability of acetonitrile, while chloroform and petroleum ether have poor solubility for the target pesticide. Therefore, acetonitrile was chosen as the optimal elution solvent.
Example (b):
(1) crushing a curcuma wenyujin medicinal material (wenzhou), sieving the curcuma wenyujin medicinal material by a third sieve, precisely weighing 3g of powder, placing the powder into a 50mL centrifuge tube, precisely adding 15mL of 1% glacial acetic acid solution, swirling the mixture until the medicine powder is completely soaked, standing the mixture for 30min, adding 15mL of acetonitrile, and swirling the mixture to uniformly mix the acetonitrile; placing the mixture on an oscillator to shake for 5 minutes in a violent mode (500 r); adding 7.5g of mixed powder (4:1) of anhydrous magnesium sulfate and anhydrous sodium sulfate, immediately shaking up and placing on a shaker to shake violently (500r) for 3 minutes, cooling on an ice bath for about 10 minutes, and centrifuging for 5 minutes at 4000 rpm; collecting supernatant 9mL, and placing in a container with purification material (anhydrous magnesium sulfate 900mg, N-propyl ethylenediamine (PSA)300mg, C)18300mg of silica gel, 300mg of silica gel and 90mg of graphitized carbon black) in a 50mL centrifuge tube, whirling to fully mix, placing on an oscillator to violently shake for 5 minutes (500r) to completely purify, and centrifuging for 5 minutes at 4000 rpm; precisely sucking 5mL of supernatant, placing the supernatant in a 50mL volumetric flask, and adding ultrapure waterMeasuring the scale marks, and mixing to obtain Curcuma wenyujin test solution.
(2) Preparing a eutectic solvent: drying betaine at 60 deg.C under vacuum for 6 hr before use, adding mixture of betaine and glycerol at a molar ratio of 1:2 into a clean beaker, mixing well, adding magnetons, heating on a heating plate at 70 deg.C at rotation speed of 300r until the mixture becomes uniform transparent liquid, and cooling to room temperature to obtain eutectic solvent.
(3) Respectively weighing 7mL of newly prepared eutectic solvent and 200mg of single-layer graphene oxide, placing the mixture in a beaker, fully stirring the mixture until the eutectic solvent and the graphene are completely and uniformly mixed, sealing, carrying out ultrasonic treatment at 60 ℃ for 3 hours, and then carrying out vacuum drying at 100 ℃ for 3 hours to obtain the eutectic solvent functionalized graphene. Weighing a proper amount of functionalized graphene, diluting the functionalized graphene with water to prepare a stock solution of 1000 mug/mL, and diluting the stock solution with water to obtain a graphene dispersion liquid of 1.5 mug/mL before use; (4) placing 5mL of the radix curcumae sample solution into a 15mL centrifuge tube, adding the graphene dispersion solution, oscillating for 2 minutes at 500r to fully adsorb a target analyte and graphene, filtering the mixed solution by using a 0.22 mu m disposable nylon filter, sucking 100 mu L of acetonitrile, pumping into a filter head, manually pressurizing to elute the target analyte, centrifuging the eluent at 13000r for 5 minutes, loading, and carrying out UHPLC analysis.
The chromatogram is shown in FIG. 10, which shows that the Curcuma wenyujin Y.H.Chen et C.Ling of this batch contains trace etofenprox residue. Preparing reference substance solutions with different concentrations by using a standard substance of fenpropathrin pesticide, and carrying out UHPLC detection according to the same chromatographic conditions to obtain a chromatogram of the fenpropathrin reference substance. And (3) taking the concentration of the fenpropathrin reference substance as an abscissa and taking the peak area of a chromatographic peak in the chromatogram as an ordinate to prepare a standard curve of fenpropathrin. The standard curves of ethofenprox, bifenthrin, fenvalerate and lambda-cyhalothrin are made according to the same method. The linear equation is shown in table 2. According to the standard curve and the peak area of the chromatographic peak of the curcuma wenyujin medicinal material extract, the ethofenprox contained in the curcuma wenyujin medicinal material is calculated to be about 0.00157 mg/g.
In order to further verify the feasibility of the method, the in-day precision, the every-day precision, the repeatability and the sample recovery rate are also examined.
Table 2: linear equations for each pesticide component.
| Pyrethroid pesticide | Linear Range (μ g/mL) | Linear equation of equations | Coefficient of correlation (R)2) |
| Fenpropathrin | 0.01-1 | y＝3493.5x-87.577 | 0.9985 |
| Ether chrysanthester | 0.01-1 | y＝3664.2x-2.166 | 0.9970 |
| Biphenthrin | 0.01-1 | y＝3444.0x+15.584 | 0.9948 |
| Fenvalerate | 0.01-1 | y＝3111.2x-50.736 | 0.9979 |
| Efficient cyhalothrin | 0.01-1 | y＝4790.3x+35.660 | 0.9956 |
Precision in the day:
50 mu L of pesticide sample solution of 100 mu g/mL and 4950 mu L of ultrapure water are placed in a 15mL centrifuge tube, 1.5 mu g/mL of graphene dispersion liquid (eutectic solvent is betaine and glycerol with a molar ratio of 1:2, and graphene is single-layer graphene oxide) is added, and the mixture is respectively oscillated for 1.5min at 500r to enable the target analyte and the eutectic solvent functionalized graphene to be fully adsorbed. The mixed solution was filtered through a 0.22 μm disposable nylon filter, 100 μ L of acetonitrile was sucked and pumped into a filter head, the target analyte was eluted by manually applying pressure, and 13000r eluate was centrifuged for 5 minutes, and the sample was loaded and subjected to UHPLC analysis.
Samples were taken for analysis 6 times at different time periods on the same day.
Precision in the daytime:
50 mu L of pesticide sample solution of 100 mu g/mL and 4950 mu L of ultrapure water are placed in a 15mL centrifuge tube, 1.5 mu g/mL of graphene dispersion liquid (eutectic solvent is betaine and glycerol with a molar ratio of 1:2, and graphene is single-layer graphene oxide) is added, and the mixture is respectively oscillated for 1.5min at 500r to enable the target analyte and the eutectic solvent functionalized graphene to be fully adsorbed. The mixed solution was filtered through a 0.22 μm disposable nylon filter, 100 μ L of acetonitrile was sucked and pumped into a filter head, the target analyte was eluted by manually applying pressure, and 13000r eluate was centrifuged for 5 minutes, and the sample was loaded and subjected to UHPLC analysis.
Samples were injected for analysis at the same time points over three days, 2 times per day.
Repeatability:
for a survey, 3 groups were made in parallel with reference to the following experimental procedure:
50 mu L of pesticide sample solution of 100 mu g/mL and 4950 mu L of ultrapure water are placed in a 15mL centrifuge tube, 1.5 mu g/mL of graphene dispersion liquid (eutectic solvent is betaine and glycerol with a molar ratio of 1:2, and graphene is single-layer graphene oxide) is added, and the mixture is respectively oscillated for 1.5min at 500r to enable the target analyte and the eutectic solvent functionalized graphene to be fully adsorbed. The mixed solution was filtered through a 0.22 μm disposable nylon filter, 100 μ L of acetonitrile was sucked and pumped into a filter head, the target analyte was eluted by manually applying pressure, and 13000r eluate was centrifuged for 5 minutes, and the sample was loaded and subjected to UHPLC analysis. The results are shown in Table 3.
Table 3: the precision in the day, the precision in the day and the repeatability of the experimental results.
And (3) sample recovery rate:
each concentration was run in parallel as 3 groups with reference to the following experimental procedure:
taking 2 wide-mouth bottles with stoppers of 30mL specifications, numbering 1 and 2, respectively adding 5mL of curcuma wenyujin test solution, adding 0.05 mu g/mL of pesticide sample solution and 1.5 mu g/mL of graphene dispersion solution into the No. 1 bottle; and adding 0.5 mu g/mL pesticide sample solution and 1.5 mu g/mL graphene dispersion liquid into a No. 2 bottle, and oscillating at 500r for 1.5 minutes to ensure that the target analyte is fully adsorbed with the eutectic solvent functionalized graphene. The mixed solution was filtered through a 0.22 μm disposable nylon filter, 100 μ L of acetonitrile was sucked and pumped into a filter head, the target analyte was eluted by manually applying pressure, and 13000r eluate was centrifuged for 5 minutes, and the sample was loaded and subjected to UHPLC analysis. The results are shown in Table 4.
Table 4: and (5) sample adding recovery rate experiment results.
The result shows that the method has the advantages of good repeatability, high precision, high detection accuracy and sensitive and reliable method.
Claims (10)
1. A method for extracting pesticides from Curcuma wenyujin is characterized by comprising the following steps:
(1) pretreating Curcuma wenyujin medicinal material to obtain Curcuma wenyujin test solution;
(2) preparing a eutectic solvent: the eutectic solvent is choline chloride in a molar ratio of: propylene glycol: water =1:1:1, choline chloride: glycerol =1:2, choline chloride: urea =1:2, betaine: glycerol =1:2, betaine: glycerol: propylene glycol =1:1:1, wherein choline chloride and betaine are hydrogen bond acceptors and the remaining reagents are hydrogen bond donors;
(3) preparing the eutectic solvent functionalized graphene by using the prepared eutectic solvent;
(4) carrying out dispersive micro-solid phase extraction on the curcuma wenyujin test solution by taking the eutectic solvent functionalized graphene as an adsorbent, centrifuging, filtering eluent, and carrying out sample analysis to represent the pesticide enrichment effect.
2. The method for extracting pesticide from curcuma aromatica as claimed in claim 1, wherein the preparation method of test solution of curcuma aromatica in step (1) is:
A) pulverizing radix Curcumae and sieving to obtain medicinal powder;
B) adding the medicinal powder into the medicinal powder in a ratio of (5-6) mL: 1g of 1% glacial acetic acid solution until the medicinal material powder is completely soaked, standing, adding acetonitrile with the same volume as the glacial acetic acid, and uniformly mixing by oscillation;
C) adding the raw materials in a mass ratio of (2-3): 1, wherein the mass ratio of the anhydrous magnesium sulfate to the anhydrous sodium sulfate is 4: 1;
D) and oscillating uniformly, cooling in an ice bath, performing centrifugal separation, taking supernatant, placing the supernatant into a centrifugal tube filled with a purifying material, oscillating, purifying, performing centrifugal separation, and diluting the supernatant to obtain the curcuma wenyujin test solution.
3. The method for extracting pesticide from curcuma aromatica as claimed in claim 1, wherein the amount of the purification material and the amount of the purification material in the centrifuge tube in step D) are as follows: 900mg/50mL of anhydrous magnesium sulfate, 300mg/50mL of N-propylethylenediamine, C18300mg/50mL, 300mg/50mL silica gel, 90mg/50mL graphitized carbon black.
4. The method for extracting pesticide from curcuma wenyujin as claimed in claim 1, wherein the preparation method of low eutectic solvent in step (2) is: and drying the hydrogen bond acceptor, mixing the hydrogen bond acceptor and the hydrogen bond donor in proportion, stirring and heating at 60-80 ℃ until the mixture becomes uniform transparent liquid, and cooling to room temperature to obtain the eutectic solvent.
5. The method for extracting pesticide from curcuma wenyujin as claimed in claim 1, wherein the preparation method of the low eutectic solvent functionalized graphene in the step (3) is as follows: weighing (3-4) mL in proportion: and mixing and uniformly stirring 100mg of eutectic solvent and graphene, sealing, performing ultrasonic treatment at 55-65 ℃ for 2-4 hours, and then performing vacuum drying at 90-110 ℃ to obtain the eutectic solvent functionalized graphene.
6. The method for extracting pesticide from curcuma aromatica as claimed in claim 5, wherein said graphene is any one of single-layer graphene oxide, aminated graphene and carboxylated graphene.
7. The method for extracting pesticide from curcuma wenyujin as claimed in claim 1, wherein the method for dispersive micro solid phase extraction in step (4) comprises: mixing the curcuma wenyujin test solution and the eutectic solvent functionalized graphene, filtering the mixed solution after oscillation adsorption, eluting with an organic solvent, centrifugally separating the eluent, and taking the supernatant for UHPLC analysis.
8. The method for extracting pesticide from curcuma wenyujin as claimed in claim 7, wherein said organic solvent is any one of methanol, acetonitrile, ethyl acetate, chloroform, petroleum ether and acetone.
9. The method for extracting pesticide from curcuma wenyujin according to claim 7, wherein the time of oscillation adsorption in the step (4) of dispersive micro-solid phase extraction is 1.0-2.5 min.
10. The method for extracting pesticide from Curcuma wenyujin Y.H. Chen et C.Ling as claimed in claim 7, wherein the filtration in step (4) is performed with 0.22 μm filter membrane.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910796496.0A CN110824030A (en) | 2019-08-27 | 2019-08-27 | Method for extracting pesticide from curcuma wenyujin |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910796496.0A CN110824030A (en) | 2019-08-27 | 2019-08-27 | Method for extracting pesticide from curcuma wenyujin |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN110824030A true CN110824030A (en) | 2020-02-21 |
Family
ID=69547872
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910796496.0A Pending CN110824030A (en) | 2019-08-27 | 2019-08-27 | Method for extracting pesticide from curcuma wenyujin |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110824030A (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113125482A (en) * | 2021-04-20 | 2021-07-16 | 浙江科技学院 | Eutectic solvent for sample preparation of cryoelectron microscope and preparation method thereof |
| CN113567578A (en) * | 2021-07-15 | 2021-10-29 | 山西大学 | SPE-DES-HPLC method for simultaneously determining two flavanol substances in Shanxi mature vinegar |
| CN113740472A (en) * | 2021-08-13 | 2021-12-03 | 杭州师范大学 | Micro-extraction method of acaricide in curcuma wenyujin |
| CN113740461A (en) * | 2021-09-08 | 2021-12-03 | 河北北方学院 | Method for detecting pesticide residue of eutectic solvent magnetic carbon nanotube dispersed solid phase extraction bactericide |
| CN115403037A (en) * | 2022-08-31 | 2022-11-29 | 西南交通大学 | Modified graphene oxide and preparation method thereof, and lubricating oil and preparation method thereof |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105203685A (en) * | 2015-09-17 | 2015-12-30 | 中国农业科学院茶叶研究所 | Pretreatment method for analyzing nicotine pesticide in tea infusion based on mesoporous silica and graphene oxide |
| CN108088943A (en) * | 2018-02-13 | 2018-05-29 | 沈阳药科大学 | Extractant-eutectic is dissolved in the application during effective component of chinese medicine measures |
| CN109557222A (en) * | 2019-01-28 | 2019-04-02 | 浙江工业大学 | A kind of Extraction and enrichment method of Sesquiterpene Polyesterss in RADIX CURCUMAE |
| US20200095400A1 (en) * | 2017-03-16 | 2020-03-26 | Oren A. Scherman | Deep Eutectic Solvent Compositions |
-
2019
- 2019-08-27 CN CN201910796496.0A patent/CN110824030A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105203685A (en) * | 2015-09-17 | 2015-12-30 | 中国农业科学院茶叶研究所 | Pretreatment method for analyzing nicotine pesticide in tea infusion based on mesoporous silica and graphene oxide |
| US20200095400A1 (en) * | 2017-03-16 | 2020-03-26 | Oren A. Scherman | Deep Eutectic Solvent Compositions |
| CN108088943A (en) * | 2018-02-13 | 2018-05-29 | 沈阳药科大学 | Extractant-eutectic is dissolved in the application during effective component of chinese medicine measures |
| CN109557222A (en) * | 2019-01-28 | 2019-04-02 | 浙江工业大学 | A kind of Extraction and enrichment method of Sesquiterpene Polyesterss in RADIX CURCUMAE |
Non-Patent Citations (1)
| Title |
|---|
| XIAOYU SONG 等: "Deep Eutectic Solvent Micro-Functionalized Graphene Assisted Dispersive Micro Solid-Phase Extraction of Pyrethroid Insecticides in Natural Products", 《FRONTIERS IN CHEMISTRY》 * |
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113125482A (en) * | 2021-04-20 | 2021-07-16 | 浙江科技学院 | Eutectic solvent for sample preparation of cryoelectron microscope and preparation method thereof |
| CN113567578A (en) * | 2021-07-15 | 2021-10-29 | 山西大学 | SPE-DES-HPLC method for simultaneously determining two flavanol substances in Shanxi mature vinegar |
| CN113567578B (en) * | 2021-07-15 | 2022-09-23 | 山西大学 | SPE-DES-HPLC method for simultaneously determining two flavanol substances in Shanxi mature vinegar |
| CN113740472A (en) * | 2021-08-13 | 2021-12-03 | 杭州师范大学 | Micro-extraction method of acaricide in curcuma wenyujin |
| CN113740461A (en) * | 2021-09-08 | 2021-12-03 | 河北北方学院 | Method for detecting pesticide residue of eutectic solvent magnetic carbon nanotube dispersed solid phase extraction bactericide |
| CN113740461B (en) * | 2021-09-08 | 2024-04-09 | 河北北方学院 | Method for detecting pesticide residues of eutectic solvent magnetic carbon nanotube dispersed solid phase extraction bactericide |
| CN115403037A (en) * | 2022-08-31 | 2022-11-29 | 西南交通大学 | Modified graphene oxide and preparation method thereof, and lubricating oil and preparation method thereof |
| CN115403037B (en) * | 2022-08-31 | 2023-08-22 | 西南交通大学 | Modified graphene oxide and preparation method thereof, lubricating oil and preparation method thereof |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110824030A (en) | Method for extracting pesticide from curcuma wenyujin | |
| CN107216228B (en) | Eutectic solvent and method for extracting anthraquinone in rheum officinale | |
| CN108802255B (en) | Method for determining content of ganoderma lucidum triterpene component in compound preparation | |
| CN101995353A (en) | Ultrafiltration membrane-solid phase extraction combined device for sample pretreatment and application thereof | |
| CN104826359A (en) | Impurity adsorption-type purification column for pre-treatment of detection of clenbuterol residue in animal urine and preparation method thereof | |
| CN107199012A (en) | A kind of magnetic fullerene nanomaterial and its application in SPE | |
| CN110794060B (en) | Method for determining spermidine content in safflower medicinal material and method for enriching spermidine | |
| CN103217498B (en) | Method for detecting dicyandiamide in milk powder with LC-MS (liquid chromatography/mass spectrometry) and sample preparation method | |
| CN113176356A (en) | Pretreatment method for detecting soil odor substances in aquaculture water | |
| CN109265494B (en) | Method for extracting kaempferol glucoside compounds from camellia reticulata | |
| CN111393470A (en) | Egg yolk lecithin and preparation method thereof | |
| CN101766667A (en) | Echinacea purpurea extract and preparing method and phenols ingredient detection method thereof | |
| CN103142474B (en) | With the composition and method of making the same that high purity bilobalide B is active component | |
| CN110922439A (en) | Method for separating and preparing gram-grade high-purity natural product | |
| CN111440184B (en) | Method for preparing high-purity carnosol | |
| CN110333301A (en) | Method that is a kind of while measuring 9 kinds of sulfa antibiotics on suspended particulate substance in water | |
| CN110028531B (en) | Method for extracting and separating flavonoid substances from soil | |
| CN110687224B (en) | Method for measuring triptolide A in tripterygium wilfordii medicinal material and tripterygium wilfordii multi-glycoside tablet prepared from tripterygium wilfordii medicinal material | |
| CN107300599A (en) | A kind of method of acidic drug in SPE liquid chromatogram combination examination liquid medicine | |
| CN110376321B (en) | Polymer continuous bed for online enriching and purifying ursolic acid and method for online enriching and purifying ursolic acid | |
| CN109212108B (en) | Gas chromatography-mass spectrometry combined method for simultaneously determining three trace quinoline herbicides in rice and soybean | |
| Kumoro et al. | Modelling of andrographolide extraction from Andrographis paniculata leaves in a soxhlet extractor | |
| CN113740472B (en) | Micro-extraction method of acaricide in curcuma wenyujin | |
| CN115343390B (en) | Method for extracting effective and harmful components in traditional Chinese medicine by matrix solid-phase dispersion | |
| CN105675773B (en) | A kind of method of prealbumin in solid extracting agent enrichment human plasma |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20200221 |