Method for detecting pesticides, heavy metals and effective components of traditional Chinese medicinal materials

Abstract

The invention discloses a method for detecting pesticides, heavy metals and active ingredients of traditional Chinese medicinal materials, and relates to the technical field of traditional Chinese medicinal material detection. The method comprises the steps of pretreatment of the traditional Chinese medicinal materials, preparation of liquid medicine, detection of the liquid medicine and post-treatment of medicine residues of the liquid medicine. A self-made multifunctional solid-phase extraction column is combined for purification treatment, and the multifunctional solid-phase extraction column can effectively remove impurities in supernate through reasonable silica gel, Flory silica and activated carbon filling combination and filling amount setting, so that the enrichment and selective separation effects on target pesticide components are improved; meanwhile, accurate detection of various pesticide residues in the traditional Chinese medicinal materials can be achieved, especially the trace pesticide residues can also reach a low detection limit, the increasingly strict pesticide residue limit standard requirement is effectively met, and the problem that an existing detection method is insufficient in sensitivity is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of Chinese medicinal material detection, in particular to a method for detecting pesticides, heavy metals and effective ingredients of Chinese medicinal materials. Background Art

[0002] Chinese herbal medicines play a vital role in the field of traditional Chinese medicine. Their quality is directly related to the clinical efficacy of Chinese medicine and the safety and effectiveness of Chinese medicine-related products. However, with the development of modern industry and agriculture and the influence of many factors such as ecological environment changes, Chinese herbal medicines are facing quality and safety risks such as pesticide residues and excessive heavy metals. At the same time, accurate determination of the content of their active ingredients is also extremely critical to controlling the quality of herbal medicines.

[0003] In the past, the commonly used methods for detecting pesticide residues in traditional Chinese medicines include gas chromatography (GC) and high performance liquid chromatography (HPLC). Gas chromatography can achieve good separation and detection for pesticides with volatility and good thermal stability, but the detection effect is poor for some thermally unstable and highly polar pesticides. Although high performance liquid chromatography can make up for the shortcomings of gas chromatography in this regard, it is sometimes difficult to meet the increasingly stringent pesticide residue limit standards in terms of detection sensitivity, especially when detecting trace pesticide residues.

[0004] At present, the detection of heavy metals in Chinese medicinal materials mainly adopts atomic absorption spectrometry (AAS), inductively coupled plasma mass spectrometry (ICP-MS), etc. Atomic absorption spectrometry has good accuracy and precision for the detection of single heavy metal elements, but when it is necessary to detect multiple heavy metal elements at the same time, the operation is cumbersome and the efficiency is low, and each element needs to be analyzed. Although inductively coupled plasma mass spectrometry can realize simultaneous rapid detection of multiple elements with high sensitivity, the instrument cost is expensive and the operation and maintenance requirements are high, which limits its widespread application in some grassroots detection units. In the sample pretreatment stage of heavy metal detection, different digestion methods will have a great impact on the results. There are many kinds of effective ingredients in Chinese medicinal materials, with complex structures and great differences in properties. Commonly used detection techniques such as ultraviolet spectrophotometry are more convenient for detecting effective ingredients with relatively simple ingredients and characteristic ultraviolet absorption. However, for Chinese medicinal materials with complex ingredients, the ultraviolet absorption peaks of multiple ingredients are easy to interfere with each other, resulting in inaccurate detection results. Although high performance liquid chromatography is one of the most widely used methods for quantitative detection of effective ingredients, the separation conditions of different effective ingredients on the chromatographic column need to be carefully optimized, and there are still challenges in separating and detecting some trace effective ingredients with extremely small polarity differences. For this reason, we propose a method for detecting pesticides, heavy metals and effective ingredients in Chinese medicinal materials. Summary of the invention

[0005] The purpose of the present invention is to provide a method for detecting pesticides, heavy metals and effective ingredients in Chinese medicinal materials.

[0006] In order to solve the problems raised in the above background technology, the present invention provides the following technical solutions: a method for detecting pesticides, heavy metals and active ingredients of Chinese medicinal materials, comprising pretreatment of Chinese medicinal materials, preparation of medicinal solution, detection of medicinal solution and post-treatment of medicinal solution and residues. The specific operation steps of the method for detecting pesticides, heavy metals and active ingredients of Chinese medicinal materials are as follows:

[0007] Step 1: Select Chinese herbal medicines, dry them, crush them for later use, mix them with water and catalyst, add composite extraction solvent in proportion after mixing, perform ultrasonic extraction and low-temperature centrifugation, and take the supernatant for later use;

[0008] Step 2: adding half of the volume of the supernatant to an extraction column for purification, performing an elution operation on the supernatant after purification, and collecting the eluate after elution for liquid chromatography detection of pesticide residues;

[0009] Step 3: Take out the precipitate after centrifugation in step 1, transfer it into a container, add diluent, use a microwave digestion instrument to digest it, drive acid to dry it, and use plasma emission spectroscopy to detect the heavy metal content;

[0010] Step 4: taking half the volume of the supernatant in step 1, passing it through a polymer column for separation, and adding an eluent for elution. After completion, the eluent is collected and the effective components are detected by liquid chromatography;

[0011] Step 5: The waste liquid after centrifugation and the waste liquid after testing are treated harmlessly, incinerated at high temperature and landfilled after stable solidification.

[0012] As a further scheme of the present invention: in the step 1, after the Chinese medicinal materials are air-dried at room temperature, they are crushed to a particle size of 80-100 mesh and mixed evenly, acetonitrile, ethyl acetate and water are mixed in a volume ratio of 3:2:1 to prepare a composite extraction solvent, and the composite solvent is mixed with the Chinese medicinal powder in a ratio of 10:1 to prepare a composite solution, the composite solution is transferred to an ultrasonic device, extracted for 30 minutes under the condition of an ultrasonic power of 300 W, and after the completion of the ultrasound, it is transferred to a centrifuge, centrifuged at a speed of 4000r / min-4500r / min for 10min-15min, and the supernatant and precipitate are taken out separately for use.

[0013] As a further scheme of the present invention: in the step 2, a multifunctional solid phase extraction column is prepared, which is filled with silica gel, Florisil and activated carbon from top to bottom in sequence, with filling amounts of 1g, 0.5g and 0.2g respectively, and each layer is separated by glass wool. During the purification process of the supernatant, 5mL-10mL of n-hexane is used for elution, and then 10mL-15mL of ethyl acetate solution containing 5% acetone is used to elute the pesticide components in the supernatant, the eluate is collected and blown dry under a nitrogen blow dryer, and after drying, 1mL-3mL of methanol is used for re-dissolution, and methanol is slowly added to the dried sample container. After adding methanol, the container is vortexed using a vortex mixer to fully contact and mix the methanol with the residue in the sample container, and vortexed for 2min-3min. After the methanol and the residue are fully mixed, the column is taken out for use.

[0014] As a further scheme of the present invention: in the step 2, ultra high performance liquid chromatography-tandem mass spectrometry is used for detection, the liquid chromatography conditions are controlled, a C18 reverse phase chromatographic column (2.1 mm×100 mm, 1.8 um) is used, the column temperature is set to 40°C-45°C, the mobile phase A is 0.1% formic acid aqueous solution, the mobile phase B is acetonitrile, and the elution operation is performed according to the set gradient elution program, the flow rate is set to 0.3 mL / min, the injection volume is 5 uL, the mass spectrometry conditions are controlled, an electrospray ion source (ESI) is used, and the positive ion mode is used for scanning, the capillary voltage is 3.5 kV, the cone voltage is 30 V, the drying gas temperature is 350°C, the drying gas flow rate is 10 L / min, and the atomization gas pressure is set to 40 psi.

[0015] As a further solution of the present invention: in the step 3, the remaining precipitate produced by centrifugation in step 1 is taken, and it is transferred into a polytetrafluoroethylene digestion tank dedicated to microwave digestion using a spoon, 5 mL of nitric acid-hydrogen peroxide mixed solution (wherein the volume ratio of nitric acid to hydrogen peroxide is maintained at 4:1) is measured, and slowly added into the digestion tank, and the mixed solution and the precipitate are mixed evenly. After completion, the digestion tank is sealed and placed in a digestion chamber of a microwave digestion instrument, and a digestion operation is performed on it according to the set power. After the digestion is completed, the temperature in the microwave digestion instrument cavity is naturally cooled to below 60°C, the digestion tank is taken out from the digestion cavity, and the internal digestion solution is transferred into a polytetrafluoroethylene crucible, and the inner wall of the digestion tank is cleaned 2-3 times with deionized water, and the cleaning solution is transferred to the crucible together, and the polytetrafluoroethylene crucible is placed in the digestion chamber. Heat the tetrafluoroethylene crucible to 120℃-150℃, and slowly add acid to drive out the operation. During the process, use a glass rod to gently stir the digestion solution to make the acid evaporate evenly until the digestion solution is close to dry (the remaining volume is about 0.5mL-1mL). After the acid is driven out, wait for the crucible to cool to room temperature, use a pipette to accurately measure 1% nitric acid solution, and slowly add it along the inner wall of the crucible. Stir with a glass rod while adding to fully dissolve the residue at the bottom of the crucible, and then transfer the solution to a 25mL volumetric flask, rinse the crucible and glass rod with 1% nitric acid solution 3-4 times, transfer the rinse solution to a volumetric flask, and then use 1% nitric acid solution to make up to the scale line, shake the volumetric flask gently, mix the solution evenly, and prepare the heavy metal digestion solution sample to be tested.

[0016] As a further scheme of the present invention: in the step three, the heavy metal content of the sample after volume adjustment is detected by inductively coupled plasma optical emission spectrometry (ICP-OES), and the specific working parameters of the instrument are set, the radio frequency power is set to 1300W, the cooling gas flow rate is maintained at 15L / min, the cooling gas is usually argon, the auxiliary gas flow rate is set to 0.5L / min-0.7L / min, the atomizing gas pressure is controlled at 200kPa, and the observation height is set to 15mm-20mm. When performing the detection, the instrument needs to be calibrated first, and a multi-element standard solution of common heavy metal elements in traditional Chinese medicine containing lead, cadmium, mercury, arsenic and copper is selected. The samples are injected in sequence according to the instrument operating procedures, and the standard curve of each element is drawn. Then, the sample solution with a certain volume is injected into the instrument injection system for detection, and the content of the corresponding heavy metal element in the sample is calculated in combination with the standard curve according to the characteristic spectral wavelength and intensity corresponding to each heavy metal element.

[0017] As a further solution of the present invention: in the step 4, a novel molecular imprinting-magnetic composite polymer column is selected for separation of effective components, one-half volume of the supernatant in step 1 is taken and slowly added to the molecular imprinting-magnetic composite polymer column, and the loading flow rate is controlled to be 0.5 mL / min-1 mL / min. After the loading is completed, 5 mL-8 mL of methanol-water (volume ratio is 1:1) solution is used as eluent, and elution is performed at the same flow rate to further remove weakly bound impurities adsorbed on the polymer column, and then 5 mL-8 mL of methanol is selected as eluent to elute the target effective components adsorbed on the composite polymer column, and then the eluent is slowly passed through the composite polymer column at a flow rate of 0.5 mL / min-1 mL / min, and the eluent is collected in a clean glass collection tube for standby use.

[0018] As a further scheme of the present invention: in the step four, high performance liquid chromatography is used to detect the effective ingredients of the collected eluate, and the specific operating parameter settings include chromatographic column selection, mobile phase setting, detector selection and parameter setting. The chromatographic column is a silica gel column (specification: 4.6mm×250mm, particle size: 5um), the mobile phase is set to methanol-water, the volume ratio is 50-70:30-50, the flow rate is set to 1mL / min, the column temperature is maintained at 30℃-35℃, the injection volume is 20uL, the detector is a UV detector, and the detection wavelength is set according to its maximum absorption wavelength.

[0019] As a further scheme of the present invention: in the step five, the waste liquids generated in each link of pesticide residue detection, heavy metal detection and effective ingredient detection are classified and collected according to the characteristics of the components, and then the corresponding pretreatment means of reduced pressure distillation, activated carbon adsorption and neutralization reaction are respectively used to reduce the pollution and treatment difficulty, the pesticide residue is detected, the qualified organic solvents in the detection waste liquid are recycled, and the rest are discharged after deep treatment to meet the standards, the heavy metal detection waste liquid is treated with an ion exchange resin adsorption column and then discharged to meet the standards, and the effective ingredient detection waste liquid is recycled after meeting the recycling standards.

[0020] By adopting the above technical solution, compared with the prior art, the beneficial effects of the present invention are:

[0021] 1. The present invention uses ultra-high performance liquid chromatography-tandem mass spectrometry technology and combines it with a self-made multifunctional solid phase extraction column for purification. The multifunctional solid phase extraction column can effectively remove impurities in the supernatant through a reasonable silica gel, Florisil and activated carbon filling combination and filling amount setting, improve the enrichment and selective separation effect of the target pesticide components, and at the same time, can achieve accurate detection of multiple pesticide residues in traditional Chinese medicines, especially for trace pesticide residues. It can also achieve a lower detection limit, effectively meet the increasingly stringent pesticide residue limit standard requirements, and solve the problem of insufficient sensitivity of existing detection methods. By using inductively coupled plasma emission spectrometry, under reasonable instrument working parameter settings, it can not only achieve simultaneous rapid detection of multiple common heavy metal elements such as lead, cadmium, mercury, arsenic, copper, etc. in traditional Chinese medicines, but also Compared with inductively coupled plasma mass spectrometry, inductively coupled plasma emission spectrometry has lower instrument cost and operation and maintenance cost, and is more convenient for widespread application in grassroots detection units. It solves the problem of the existing heavy metal detection methods that are difficult to balance between detection efficiency and cost, and improves the practicality and popularity of heavy metal detection. By using a new molecular imprinting-magnetic composite polymer column to separate and process the effective ingredients, and utilizing the specific recognition ability of molecular imprinting polymers for target effective ingredients and the characteristics of magnetic nanoparticles for rapid separation and recovery, it can efficiently and specifically enrich the target effective ingredients from complex supernatants, remove impurity interference, and then combine with optimized high-performance liquid chromatography detection, it can more accurately perform quantitative detection of effective ingredients in traditional Chinese medicines, thereby improving the accuracy and reliability of effective ingredient detection.

[0022] 2. The present invention can effectively separate and detect pesticides of different properties (including thermal instability, large polarity difference, etc.) through optimized liquid chromatography conditions and mass spectrometry technology, broaden the scope of detectable pesticides, and enable various pesticide residues in Chinese medicinal materials to be more comprehensively understood, making up for the limitations of traditional gas chromatography in this regard. Through a specific nitric acid-hydrogen peroxide mixture (the volume ratio is controlled to be 4:1) and an optimized microwave digestion program, the heavy metal elements in the Chinese medicinal material samples can be fully and stably digested out, avoiding the shortcomings of traditional digestion methods, ensuring the accuracy of the digested samples for detection, and laying the foundation for the subsequent accurate determination of heavy metal content. By adjusting the ratio of methanol-water in the mobile phase of high-performance liquid chromatography detection, it can adapt to the detection of effective ingredients of Chinese medicinal materials with various properties and structures, enhance the versatility and adaptability of the detection of effective ingredients of different Chinese medicinal materials, and overcome the defect of limited detection ability of existing methods for complex effective ingredient systems. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a schematic diagram of the process of Chinese medicinal material detection in an embodiment of the present invention;

[0024] Figure 2 A schematic diagram of setting a gradient elution program in an embodiment of the present invention;

[0025] Figure 3 Schematic diagram of microwave digestion program setting in an embodiment of the present invention. DETAILED DESCRIPTION

[0026] The specific embodiments of the present invention are further described below in conjunction with the accompanying drawings. It should be noted that the description of these embodiments is used to help understand the present invention, but does not constitute a limitation of the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0027] The present invention discloses a method for detecting pesticides, heavy metals and active ingredients of Chinese medicinal materials, which comprises pretreatment of Chinese medicinal materials, preparation of medicinal solution, detection of medicinal solution and post-treatment of medicinal solution and medicinal residue. The specific operation steps of the method for detecting pesticides, heavy metals and active ingredients of Chinese medicinal materials are as follows:

[0028] Step 1: Select Chinese herbal medicines, dry them, crush them for later use, mix them with water and catalyst, add composite extraction solvent in proportion after mixing, perform ultrasonic extraction and low-temperature centrifugation, and take the supernatant for later use;

[0029] Step 2: adding half of the volume of the supernatant to an extraction column for purification, performing an elution operation on the supernatant after purification, and collecting the eluate after elution for liquid chromatography detection of pesticide residues;

[0030] Step 3: Take out the precipitate after centrifugation in step 1, transfer it into a container, add diluent, use a microwave digestion instrument to digest it, drive acid to dry it, and use plasma emission spectroscopy to detect the heavy metal content;

[0031] Step 4: taking half the volume of the supernatant in step 1, passing it through a polymer column for separation, and adding an eluent for elution. After completion, the eluent is collected and the effective components are detected by liquid chromatography;

[0032] Step 5: The waste liquid after centrifugation and the waste liquid after testing are treated harmlessly, incinerated at high temperature and landfilled after stable solidification.

[0033] In one embodiment of the present invention: in step 1, after drying the Chinese medicinal materials at room temperature, they are crushed to a particle size of 80-100 mesh and mixed evenly, acetonitrile, ethyl acetate and water are mixed in a volume ratio of 3:2:1 to prepare a composite extraction solvent, and the composite solvent is mixed with the Chinese medicinal powder in a ratio of 10:1 to prepare a composite solution, the composite solution is transferred to an ultrasonic device, extracted for 30 minutes under an ultrasonic power of 300 W, and after the completion of the ultrasound, it is transferred to a centrifuge and centrifuged at a speed of 4000r / min-4500r / min for 10min-15min, and the supernatant and precipitate are taken out separately for use.

[0034] In one embodiment of the present invention: in step 2, a multifunctional solid phase extraction column is prepared, which is filled with silica gel, Florisil and activated carbon in sequence from top to bottom, with filling amounts of 1g, 0.5g and 0.2g respectively, and each layer is separated by glass wool. During the purification process of the supernatant, 5mL-10mL of n-hexane is used for elution, and then 10mL-15mL of ethyl acetate solution containing 5% acetone is used to elute the pesticide components in the supernatant, the eluate is collected and blown dry under a nitrogen blow dryer, and after drying, 1mL-3mL of methanol is used for re-dissolution, and methanol is slowly added to the dried sample container. After adding methanol, the container is vortexed using a vortex mixer to fully contact and mix the methanol with the residue in the sample container, and vortexed for 2min-3min. After the methanol and the residue are fully mixed, they are taken out for use.

[0035] In one embodiment of the present invention: in step 2, ultra high performance liquid chromatography-tandem mass spectrometry is used for detection, the liquid chromatography conditions are controlled, a C18 reverse phase chromatographic column (2.1 mm×100 mm, 1.8 um) is used, the column temperature is set to 40°C-45°C, the mobile phase A is 0.1% formic acid aqueous solution, the mobile phase B is acetonitrile, the elution operation is performed according to the set gradient elution program, the flow rate is set to 0.3 mL / min, the injection volume is 5 uL, the mass spectrometry conditions are controlled, an electrospray ion source (ESI) is used, and the positive ion mode is used for scanning, the capillary voltage is 3.5 kV, the cone voltage is 30 V, the drying gas temperature is 350°C, the drying gas flow rate is 10 L / min, and the atomization pressure is set to 40 psi.

[0036] In one embodiment of the present invention: in step three, the remaining precipitate produced by centrifugation in step one is taken, and it is transferred into a polytetrafluoroethylene digestion tank dedicated to microwave digestion using a spoon, 5 mL of nitric acid-hydrogen peroxide mixed solution (wherein the volume ratio of nitric acid to hydrogen peroxide is maintained at 4:1) is measured, and slowly added to the digestion tank, and the mixed solution and the precipitate are mixed evenly. After completion, the digestion tank is sealed and placed in a digestion chamber of a microwave digestion instrument, and a digestion operation is performed on it according to the set power. After the digestion is completed, the temperature in the microwave digestion instrument cavity is naturally cooled to below 60°C, the digestion tank is taken out from the digestion cavity, and the internal digestion solution is transferred into a polytetrafluoroethylene crucible, and the inner wall of the digestion tank is cleaned 2-3 times with deionized water, and the cleaning solution is transferred to the crucible together, and the polytetrafluoroethylene crucible is placed in the digestion chamber of the microwave digestion instrument. Heat the tetrafluoroethylene crucible to 120℃-150℃, and slowly add acid to drive out the operation. During the process, use a glass rod to gently stir the digestion solution to make the acid evaporate evenly until the digestion solution is close to dry (the remaining volume is about 0.5mL-1mL). After the acid is driven out, wait for the crucible to cool to room temperature, use a pipette to accurately measure 1% nitric acid solution, and slowly add it along the inner wall of the crucible. Stir with a glass rod while adding to fully dissolve the residue at the bottom of the crucible, and then transfer the solution to a 25mL volumetric flask, rinse the crucible and glass rod with 1% nitric acid solution 3-4 times, transfer the rinse solution to a volumetric flask, and then use 1% nitric acid solution to make up to the scale line, shake the volumetric flask gently, mix the solution evenly, and prepare the heavy metal digestion solution sample to be tested.

[0037] In one embodiment of the present invention: in step three, inductively coupled plasma optical emission spectrometry (ICP-OES) is used to detect the heavy metal content of the sample after volume adjustment, and the specific working parameters of the instrument are set, the radio frequency power is set to 1300W, the cooling gas flow rate is maintained at 15L / min, the cooling gas is usually argon, the auxiliary gas flow rate is set to 0.5L / min-0.7L / min, the atomizing gas pressure is controlled at 200kPa, and the observation height is set to 15mm-20mm. When performing the detection, the instrument needs to be calibrated first, and a multi-element standard solution containing common heavy metal elements in traditional Chinese medicines such as lead, cadmium, mercury, arsenic and copper is selected. The samples are injected in sequence according to the instrument operating procedures, and the standard curve of each element is drawn. Then, the sample solution with a certain volume is injected into the instrument injection system for detection, and the content of the corresponding heavy metal element in the sample is calculated in combination with the standard curve according to the characteristic spectral wavelength and intensity corresponding to each heavy metal element.

[0038] In one embodiment of the present invention: in step 4, a novel molecular imprinting-magnetic composite polymer column is selected for separation of effective components, one-half volume of the supernatant in step 1 is taken and slowly added to the molecular imprinting-magnetic composite polymer column, and the loading flow rate is controlled to be 0.5 mL / min-1 mL / min. After the loading is completed, 5 mL-8 mL of methanol-water (volume ratio is 1:1) solution is used as eluent, and elution is performed at the same flow rate to further remove weakly bound impurities adsorbed on the polymer column, and then 5 mL-8 mL of methanol is selected as eluent to elute the target effective components adsorbed on the composite polymer column, and then the eluent is slowly passed through the composite polymer column at a flow rate of 0.5 mL / min-1 mL / min, and the eluent is collected in a clean glass collection tube for standby use.

[0039] In one embodiment of the present invention: in step four, high performance liquid chromatography is used to detect the effective ingredients of the collected eluate, and the specific operating parameter settings include chromatographic column selection, mobile phase setting, detector selection and parameter setting. The chromatographic column is a silica gel column (specification: 4.6mm×250mm, particle size: 5um), the mobile phase is set to methanol-water, the volume ratio is 50-70:30-50, the flow rate is set to 1mL / min, the column temperature is maintained at 30℃-35℃, the injection volume is 20uL, the detector is a UV detector, and the detection wavelength is set according to its maximum absorption wavelength.

[0040] In one embodiment of the present invention: in step five, the waste liquids generated in each link of pesticide residue detection, heavy metal detection and effective ingredient detection are classified and collected according to the characteristics of the components, and then the corresponding pretreatment means of reduced pressure distillation, activated carbon adsorption and neutralization reaction are used to reduce the pollution and treatment difficulty, the pesticide residue is detected, the qualified organic solvents in the detection waste liquid are recycled, and the rest are discharged after deep treatment to meet the standards, the heavy metal detection waste liquid is treated with an ion exchange resin adsorption column and then discharged to meet the standards, and the effective ingredient detection waste liquid is recycled after meeting the recycling standards.

[0041] In one embodiment of the present invention: in step 2, the ultra-high performance liquid chromatography operation step includes a liquid chromatography part operation and a mass spectrometry part operation, wherein the liquid chromatography part operation is as follows:

[0042] Mobile phase preparation: 0.1% formic acid aqueous solution, use ultrapure water (resistivity generally needs to reach 18.2MΩ·cm), accurately measure an appropriate amount of ultrapure water with a measuring cylinder, pour it into a suitable glass bottle, and then use a pipette or micro-syringe to accurately absorb the corresponding amount of formic acid. According to 1L of solution, absorb 1mL of formic acid and slowly add it to the ultrapure water, stirring gently while adding to make it fully mixed. Use a pH meter to test the pH value of the solution. After ensuring that it meets the requirements, filter it through a 0.22um or 0.45um filter membrane to remove possible tiny particle impurities. Transfer the filtered mobile phase A to the mobile phase storage bottle dedicated to the liquid chromatograph and mark it;

[0043] Acetonitrile: Choose chromatographically pure acetonitrile. Filter an appropriate amount of acetonitrile through a 0.22um or 0.45um filter membrane to remove impurities, then transfer it to the corresponding mobile phase storage bottle and mark it as mobile phase B.

[0044] Check the chromatographic column and connecting pipes, take out the C18 reverse phase chromatographic column (2.1mm×100mm, 1.8um), check whether the appearance of the chromatographic column is damaged, whether the seals at both ends are in good condition, and correctly install the chromatographic column in the corresponding slot position in the column oven of the liquid chromatograph according to the markings on the instrument to ensure that the connection is firm to prevent leakage. At the same time, check whether the connecting pipes from the mobile phase storage bottle to the injector, from the injector to the chromatographic column, and from the chromatographic column to the detector are tightly connected and have no bends or blockages. If necessary, clean the pipes appropriately. After maintenance, reconnect them, turn on the power of the liquid chromatograph host, column oven, detector, etc. in turn, start the corresponding liquid chromatography control software on the computer, and wait for the instrument to perform self-test. During the self-test, the software will display the status information of each component. Confirm that each part has passed the self-test without any error prompts. In the software interface, set the column oven temperature to 40°C and wait for the column temperature to stabilize at the set value (the column temperature change can be monitored in real time through the software. Generally, it is considered to be stable when it is stable within the range of ±0.5°C of the set temperature. This process may take 10min-15min);

[0045] Before injection, set the flow rate and gradient for elution. In the parameter setting interface of the liquid chromatography control software, set the flow rate to 0.3 mL / min, and then set the gradient elution program according to the detection target and method requirements, as shown in the attached figure. Figure 2 As shown, the ratio of mobile phase A and mobile phase B corresponding to each time node is input into the software, and the instrument is operated for elution according to the set program, so that the pesticide components with different retention properties can be eluted at the appropriate time, thus achieving a better separation effect;

[0046] The operation steps of the mass spectrometry part are as follows: set the mass spectrometry parameters. In the parameter setting interface of the mass spectrometry control software, select the electrospray ion source (ESI) and set it to the positive ion mode scan. Then, as required, set the capillary voltage to 3.5 kV, the cone voltage to 30 V, the drying gas temperature to 350 ° C, the drying gas flow rate to 10 L / min, and the nebulizer gas pressure to 40 psi. At the same time, according to the range of pesticide types to be detected and the required resolution, sensitivity and other requirements, set the mass scan range to m / z 50-1000, that is, detect ion signals with a mass-to-charge ratio between 50 and 1000. The scan time is set to 0 min-40 min, which is synchronized with the liquid chromatography acquisition time. The data acquisition mode selects the full scan mode or the ion monitoring mode, which is determined according to the actual situation. The full scan mode can obtain more comprehensive ion information, and the selected ion monitoring mode monitors specific ions with higher sensitivity, ensuring that the mass spectrometer can accurately detect and analyze the pesticide components eluted and ionized from the liquid chromatography column;

[0047] When the liquid chromatography starts to inject samples for elution, pay attention to the operating status of the mass spectrometer on the mass spectrometer control software interface, observe the spray of the ion source, whether the vacuum degree remains stable, whether the intensity of the detected ion signal is within a reasonable range, etc., to ensure that the mass spectrometer works normally and can effectively detect the ion signals of the pesticide components in the sample;

[0048] According to the above operations, the pesticide components in the collected samples are accurately detected and analyzed, and the pesticide residues in the samples are judged based on the obtained data. In the actual operation process, appropriate optimization and adjustment are carried out according to factors such as sample characteristics to obtain the best detection effect.

[0049] In one embodiment of the present invention: in step three, as shown in the attached Figure 2 As shown in the figure, in the digestion procedure, the method of gradually heating up and maintaining the temperature in multiple stages is adopted. Compared with the traditional program of single heating rate and temperature maintenance, the digestion reaction can be more gentle and complete, and the problems of solution boiling, sample splashing and incomplete digestion caused by too fast heating can be avoided. Especially for the heavy metal elements bound in the complex matrix of Chinese medicinal materials, their chemical bonds can be better destroyed, so that they can be completely converted into ions and enter the solution, thereby improving the digestion efficiency and recovery rate.

[0050] In one embodiment of the present invention: In step 4, before the detection, the high performance liquid chromatograph also needs to be calibrated, and a standard solution containing the target active ingredient is prepared (the concentration range is reasonably configured according to the actual detection requirements and the instrument detection limit, such as 0ug / mL-100ug / mL), and the samples are injected in sequence according to the instrument operating procedures, and the standard curves of each active ingredient are drawn to ensure that the correlation coefficient (R 2) reaches above 0.999 to ensure the accuracy of quantitative analysis, and then the collected eluate samples are injected into the instrument injection system for detection. According to the chromatographic peak retention time, peak area and other information corresponding to each active ingredient, the content of the corresponding active ingredient in the sample is calculated in combination with the standard curve. For the setting of the mobile phase, when detecting ginsenoside active ingredients, the volume ratio of mobile phase methanol-water is 70:30, and when detecting flavonoid active ingredients, the volume ratio of mobile phase methanol-water is 50:50.

[0051] Example

[0052] Taking ginseng as an example,

[0053] Select an appropriate amount of ginseng Chinese medicinal materials with complete appearance and no obvious mildew and insect damage, spread them evenly on a clean, ventilated and dust-proof drying platform, and dry them naturally at room temperature of 20°C and 50% humidity. During the period, turn the ginseng Chinese medicinal materials from time to time until the water content of the ginseng Chinese medicinal materials is reduced to about 9%, and then put the dried ginseng into a Chinese medicine grinder, set the speed to 1800r / min for crushing, sieve after crushing, collect ginseng powder with a particle size of 80-100 mesh, and mix it thoroughly to obtain 10g ginseng powder for use, accurately measure acetonitrile, ethyl acetate and water, mix them in a separating funnel at a volume ratio of 3:2:1, and prepare a composite extraction solvent, put the above 10g ginseng powder in a glass container, and mix them at a solid-liquid ratio of 10:1 (g / mL ) add 100mL of composite extraction solvent, then add 10mL of deionized water and 0.05g of food-grade enzyme as a catalyst, use a magnetic stirrer to stir at a stirring speed of 400r / min for 12min to fully mix the components to obtain a composite solution, transfer the composite solution to an ultrasonic device with an ultrasonic power of 300W, a frequency of 40kHz and a constant temperature function, set the temperature to 32°C, and perform ultrasonic extraction for 30min. After the ultrasonication, immediately transfer the solution to a high-speed refrigerated centrifuge precooled to 6°C, centrifuge at a speed of 4200r / min for 12min, collect the supernatant and precipitate into different clean centrifuge tubes, the supernatant volume is about 90mL, and store the precipitate for subsequent heavy metal detection;

[0054] A self-made multifunctional solid phase extraction column was prepared. 1 g of silica gel, 0.5 g of Florisil and 0.2 g of activated carbon were sequentially filled from bottom to top. Each layer was separated by glass wool. 45 mL of supernatant was accurately measured and slowly added to the above extraction column. The loading flow rate was controlled to be 1.5 mL / min. After the loading was completed, 8 mL of n-hexane was used for elution. Then, 12 mL of ethyl acetate solution containing 5% acetone was used to elute the pesticide components in the supernatant. The eluate was collected in a glass collection bottle. The collected eluate was placed under a nitrogen blow dryer and dried. Then, 2 mL of methanol was used for re-dissolution. The operation was slow when adding methanol. After adding, a vortex mixer was used to vortex and oscillate for 2.5 min at a speed of 2000 r / min to fully mix the methanol and the residue and then take it out for use.

[0055] For mobile phase A (0.1% formic acid aqueous solution), use a measuring cylinder to accurately measure 1000 mL of ultrapure water with a resistivity of 18.2 MΩ·cm and pour it into a glass bottle. Use a pipette to accurately absorb 1 mL of formic acid and slowly add it into the ultrapure water. Stir gently while adding to make it fully mixed. After using a pH meter to test the pH value of the solution to meet the requirements, filter it through a 0.22 um filter membrane, transfer the filtered mobile phase A to a mobile phase storage bottle dedicated to the liquid chromatograph and mark it. For mobile phase B (acetonitrile), use chromatographically pure acetonitrile, directly filter it through a 0.22 um filter membrane to remove impurities, transfer it to the corresponding mobile phase storage bottle and mark it. Note: Take out the C18 reverse phase chromatographic column, check that the appearance is not damaged and the two ends are well sealed, then correctly install it in the corresponding slot position in the column oven of the liquid chromatograph to ensure that the connection is firm. Check that each connecting pipe is tight and has no bends or blockages. Then turn on the power of the liquid chromatograph host, the column oven, and the detector in turn, start the corresponding liquid chromatography control software on the computer and wait for the instrument to pass the self-test. Set the column oven temperature to 42°C in the software interface, wait until the column temperature stabilizes at the set value (stable within the range of 42°C±0.5°C, which takes about 12 minutes), then set the flow rate to 0.3mL / min in the parameter setting interface of the software, and follow the instructions as shown in the attached Figure 2 The gradient elution program was set as shown in the figure. In the parameter setting interface of the mass spectrometry control software, the electrospray ion source was selected and set to the positive ion mode scan, the capillary voltage was set to 3.5 kV, the cone voltage was set to 30 V, the drying gas temperature was set to 350 ° C, the drying gas flow rate was set to 10 L / min, the nebulizer gas pressure was set to 40 psi, the mass scan range was set to m / z 50-1000, the scan time was set to 0 min-40 min, and the data acquisition mode was selected as the full scan mode;

[0056] 5uL of the reconstituted sample was injected into the liquid chromatography injection system for elution. At the same time, the mass spectrometer operation status was monitored in the mass spectrometer control software interface to ensure that it was working properly and could effectively detect the ion signals of the pesticide components in the sample. The pesticide residues in the ginseng sample were determined based on the obtained data. The common pesticide residues detected were:

[0057] The content of chlorpyrifos is 0.02mg / kg, and the content of carbendazim is 0.015mg / kg;

[0058] Use a clean plastic spoon to transfer all the precipitate obtained by centrifugation to a polytetrafluoroethylene digestion tank dedicated for microwave digestion. Measure 5 mL of nitric acid-hydrogen peroxide mixture and slowly add it to the digestion tank. Gently shake the digestion tank while adding to mix the mixture and the precipitate. Seal the digestion tank and place it in the digestion chamber of the microwave digestion instrument. Figure 3 Digestion was performed using the microwave digestion program shown in the figure. After digestion was completed, the temperature in the microwave digestion instrument cavity naturally cooled to about 50°C, the digestion tank was taken out from the digestion chamber, the lid was slowly opened, and the internal digestion solution was transferred to a polytetrafluoroethylene crucible. The inner wall of the digestion tank was cleaned 3 times with 5 mL of deionized water, and the cleaning solution was transferred to the crucible. The polytetrafluoroethylene crucible was placed on a hot plate, the hot plate temperature was set to 130°C, and it was slowly heated to drive out the acid. During the process, a glass rod was used to gently stir the digestion solution to make the acid evaporate evenly until the digestion solution The residual volume is about 0.8mL. After the acid is driven out, wait for the crucible to cool to room temperature, use a pipette to accurately measure 1% nitric acid solution, slowly add it along the inner wall of the crucible, stir with a glass rod while adding, so that the residue at the bottom of the crucible is fully dissolved, and then transfer the solution to a 25mL volumetric flask, and then rinse the crucible and glass rod with 3mL of 1% nitric acid solution 3 times, and the rinse solution is also transferred to the volumetric flask, and finally use 1% nitric acid solution to make it up to the scale line, and gently shake the volumetric flask to mix the solution evenly to obtain the heavy metal digestion solution sample to be detected;

[0059] Inductively coupled plasma emission spectrometry was used to detect the heavy metal content of the sample after volume adjustment, and the working parameters of the instrument were set as follows:

[0060] The RF power was set to 1300W, the cooling gas flow rate was maintained at 15L / min, the auxiliary gas flow rate was set to 0.6L / min, the atomizing gas pressure was controlled at 200kPa, and the observation height was set to 18mm. Before the test, a multi-element standard solution containing lead (Pb), cadmium (Cd), mercury (Hg), arsenic (As) and copper (Cu) (concentration range of 0ug / mL-100ug / mL) was selected, and the samples were injected in sequence according to the instrument operating procedures. The standard curve of each element was drawn, and the correlation coefficient (R 2) all reached above 0.999, and then the fixed volume sample solution was injected into the instrument sampling system for detection. After detection, the lead content in the ginseng sample was 0.5mg / kg, the cadmium content was 0.05mg / kg, the mercury content was 0.01mg / kg, the arsenic content was 0.2mg / kg, and the copper content was 2mg / kg;

[0061] Take the remaining 45mL of supernatant and slowly add it to the novel molecular imprinting-magnetic composite polymer column, control the loading flow rate to 0.8mL / min, after the loading is completed, use 6mL of methanol-water (volume ratio of 1:1) solution as eluent, elute at the same flow rate to further remove the weakly bound impurities adsorbed on the polymer column, and then use 6mL of methanol as eluent to elute the target active ingredients (taking ginsenosides as an example) adsorbed on the composite polymer column, and slowly pass the eluent through the composite polymer column at a flow rate of 0.8mL / min. Combine polymer column, collect eluent into clean glass collection tube for later use, select silica gel column (specification 4.6mm×250mm, particle size 5um) and install it on high performance liquid chromatograph, check the instrument connection and the status of each component is normal, turn on the instrument power and start the control software, set the mobile phase to methanol-water (volume ratio of 70:30), the flow rate is set to 1mL / min, the column temperature is maintained at 32℃, the detector is selected as ultraviolet detector, the detection wavelength is set to 203nm according to the maximum absorption wavelength of ginsenosides, and the injection volume is 20uL;

[0062] Before testing, prepare a standard solution containing ginsenosides (concentration range 0ug / mL-100ug / mL), inject samples in sequence according to the instrument operating procedures, draw a standard curve, and ensure the correlation coefficient (R 2 ) reaches above 0.999, and then the collected eluate sample is injected into the instrument sampling system for detection, and the content of ginsenoside in the sample is calculated to be 5% based on the chromatographic peak retention time, peak area and other information combined with the standard curve;

[0063] Waste liquids (rinsing waste liquid, elution waste liquid, liquid chromatography mobile phase waste liquid, etc.) generated in each link of pesticide residue detection are collected and classified according to their component characteristics. Digestion and cleaning wastewater, acid removal waste liquid, and waste liquid containing nitric acid and trace heavy metal ions generated by heavy metal detection are collected separately. Rinsing waste liquid and liquid chromatography detection waste liquid generated by effective component detection are stored in different categories.

[0064] Wastewater pretreatment and final treatment,

[0065] Pesticide residue detection waste liquid:

[0066] For waste liquid containing organic solvents, vacuum distillation is used, and the recovered organic solvents are collected and kept as laboratory reagents after passing the test. The remaining waste liquid containing acid and trace pesticides is adsorbed with activated carbon (15g of activated carbon is added to each liter of waste liquid, stirred for 45 minutes and then filtered), and then transferred to a professional institution for deep treatment using a combination of advanced oxidation and biological treatment, and discharged after meeting the test standards;

[0067] Heavy metal detection waste liquid:

[0068] The pH value of "digestion and cleaning wastewater" is adjusted to neutral, and then initially treated by sand filtration and activated carbon adsorption. After testing to meet the standards, it is discharged routinely. "Acid-dripping wastewater" and "wastewater containing nitric acid and trace heavy metals" are neutralized and filtered by adding calcium hydroxide powder. The filtrate is deeply treated with ion exchange resin adsorption columns until it meets the discharge standards, and the resulting precipitate is properly stored as hazardous waste;

[0069] Active ingredient detection waste liquid:

[0070] The combined leaching waste liquid and liquid chromatography detection waste liquid are firstly recovered through reverse osmosis membrane separation technology, and 150mL / L of 30% hydrogen peroxide solution is added to the concentrated organic waste liquid, and after oxidation treatment at 55°C and stirring speed of 400r / min, the water quality index is tested. If it meets the recycling standard, it will be recycled after further treatment. If it does not meet the standard, it will be treated by activated carbon adsorption, biodegradation and other means until it meets the discharge standard;

[0071] Drug residue treatment:

[0072] The ginseng residue after testing is determined to be general solid waste. After composting, it is used as organic fertilizer for soil improvement in gardens and green spaces.

[0073] Through the above embodiments, the specific application of a method for detecting pesticides, heavy metals and active ingredients in Chinese medicinal materials in the detection of ginseng Chinese medicinal materials is demonstrated, and the feasibility and effectiveness of the detection method are verified from various aspects, which can provide a reliable detection means for quality control of ginseng and other Chinese medicinal materials.

[0074] The embodiments of the present invention are described in detail above with reference to the accompanying drawings, but the present invention is not limited to the described embodiments. For those skilled in the art, various changes, modifications, substitutions and variations of these embodiments are made without departing from the principles and spirit of the present invention, and still fall within the scope of protection of the present invention.

[0075] In the description of the specification, the description with reference to the terms "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0076] The above contents are merely examples and explanations of the present invention. Various modifications or additions to the specific embodiments described or replacements in similar ways by technicians in the technical field shall fall within the protection scope of the present invention as long as they do not deviate from the invention or exceed the scope defined by the claims.

[0077] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A method for detecting pesticides, heavy metals and active ingredients in Chinese medicinal materials, comprising pretreatment of Chinese medicinal materials, preparation of medicinal solution, detection of medicinal solution and post-treatment of medicinal solution and residue, characterized in that: The specific operation steps of the method for detecting pesticides, heavy metals and active ingredients of Chinese medicinal materials are as follows: Step 1: Select Chinese herbal medicines, dry them, crush them for later use, mix them with water and catalyst, add composite extraction solvent in proportion after mixing, perform ultrasonic extraction and low-temperature centrifugation, and take the supernatant for later use; Step 2: adding half of the volume of the supernatant to an extraction column for purification, performing an elution operation on the supernatant after purification, and using the eluent to perform liquid chromatography to detect pesticide residues; Step 3: Take out the precipitate after centrifugation in step 1, transfer it into a container, add diluent, use a microwave digestion instrument to digest it, drive acid to dry it, and use plasma emission spectroscopy to detect the heavy metal content; Step 4: taking half the volume of the supernatant in step 1, passing it through a polymer column for separation, and adding an eluent for elution. After completion, the eluent is collected and the effective components are detected by liquid chromatography; Step 5: The waste liquid after centrifugation and the waste liquid after testing are treated harmlessly, incinerated at high temperature and landfilled after stable solidification.

2. The method for detecting pesticides, heavy metals and active ingredients in Chinese medicinal materials according to claim 1, characterized in that: In the step 1, after the Chinese medicinal materials are air-dried at room temperature, they are crushed to a particle size of 80-100 mesh and mixed evenly, acetonitrile, ethyl acetate and water are mixed in a volume ratio of 3:2:1 to prepare a composite extraction solvent, and the composite solvent is mixed with the Chinese medicinal powder in a ratio of 10:1 to prepare a composite solution, the composite solution is transferred to an ultrasonic device, extracted for 30 minutes under the condition of an ultrasonic power of 300 W, and after the completion of the ultrasound, it is transferred to a centrifuge, centrifuged at a speed of 4000r / min-4500r / min for 10min-15min, and the supernatant and precipitate are respectively taken out for use.

3. The method for detecting pesticides, heavy metals and active ingredients in Chinese medicinal materials according to claim 1, characterized in that: In the step 2, a multifunctional solid phase extraction column is prepared, which is filled with silica gel, Florisil and activated carbon from top to bottom in sequence, with filling amounts of 1g, 0.5g and 0.2g respectively, and each layer is separated by glass wool. During the purification process of the supernatant, 5mL-10mL of n-hexane is used for elution, and then 10mL-15mL of ethyl acetate solution containing 5% acetone is used to elute the pesticide components in the supernatant, the eluate is collected and blown dry under a nitrogen blow dryer, and after drying, 1mL-3mL of methanol is used for re-dissolution, and methanol is slowly added to the dried sample container. After adding methanol, the container is vortexed using a vortex mixer to fully contact and mix the methanol with the residue in the sample container, and vortexed for 2min-3min. After the methanol and the residue are fully mixed, the mixture is taken out for use.

4. The method for detecting pesticides, heavy metals and active ingredients in a Chinese medicinal material according to claim 1, characterized in that: In the step 2, ultra high performance liquid chromatography-tandem mass spectrometry is used for detection, and the liquid chromatography conditions are controlled, a C18 reverse phase chromatographic column (2.1 mm×100 mm, 1.8 um) is used, the column temperature is set to 40°C-45°C, mobile phase A is 0.1% formic acid aqueous solution, mobile phase B is acetonitrile, and elution operation is performed according to the set gradient elution program, the flow rate is set to 0.3 mL / min, the injection volume is 5 uL, and the mass spectrometry conditions are controlled, an electrospray ion source (ESI) is used, and scanning is performed in positive ion mode, the capillary voltage is 3.5 kV, the cone voltage is 30 V, the drying gas temperature is 350°C, the drying gas flow rate is 10 L / min, and the atomization pressure is set to 40 psi.

5. The method for detecting pesticides, heavy metals and active ingredients in Chinese medicinal materials according to claim 1, characterized in that: In the step 3, the remaining precipitate produced by centrifugation in step 1 is taken, and it is transferred into a polytetrafluoroethylene digestion tank dedicated to microwave digestion using a spoon, 5 mL of nitric acid-hydrogen peroxide mixed solution (wherein the volume ratio of nitric acid to hydrogen peroxide is maintained at 4:1) is measured, and slowly added into the digestion tank, and the mixed solution and the precipitate are evenly mixed, and after completion, the digestion tank is sealed and placed in a digestion chamber of a microwave digestion instrument, and a digestion operation is performed on it according to the set power. After the digestion is completed, the temperature in the microwave digestion instrument cavity is naturally cooled to below 60° C., the digestion tank is taken out from the digestion cavity, and the internal digestion solution is transferred into a polytetrafluoroethylene crucible, and the inner wall of the digestion tank is cleaned 2-3 times with deionized water, and the cleaning solution is transferred to the crucible together, and the polytetrafluoroethylene crucible is placed in the crucible. Heat to 120°C-150°C, slowly add to drive out the acid, use a glass rod to gently stir the digestion solution during the process to make the acid evaporate evenly, until the digestion solution is close to dry state (the remaining volume is about 0.5mL-1mL), after the acid is driven out, wait for the crucible to cool to room temperature, use a pipette to accurately measure 1% nitric acid solution, slowly add it along the inner wall of the crucible, stir with a glass rod while adding, fully dissolve the residue at the bottom of the crucible, and then transfer the solution to a 25mL volumetric flask, rinse the crucible and the glass rod with 1% nitric acid solution 3-4 times, transfer the rinse solution to the volumetric flask, and then use 1% nitric acid solution to make up to the scale line, gently shake the volumetric flask, mix the solution evenly, and obtain the heavy metal digestion solution sample to be detected.

6. The method for detecting pesticides, heavy metals and active ingredients in Chinese medicinal materials according to claim 1, characterized in that: In the step three, inductively coupled plasma optical emission spectrometry (ICP-OES) is used to detect the heavy metal content of the sample after volume adjustment, and the specific working parameters of the instrument are set, the radio frequency power is set to 1300W, the cooling gas flow rate is maintained at 15L / min, the cooling gas is usually argon, the auxiliary gas flow rate is set to 0.5L / min-0.7L / min, the atomizing gas pressure is controlled at 200kPa, and the observation height is set to 15mm-20mm. When performing the detection, the instrument needs to be calibrated first, and a multi-element standard solution of common heavy metal elements in traditional Chinese medicine containing lead, cadmium, mercury, arsenic and copper is selected. The samples are injected in sequence according to the instrument operating procedures, and the standard curve of each element is drawn. Then, the sample solution with a certain volume is injected into the instrument sampling system for detection, and the content of the corresponding heavy metal element in the sample is calculated in combination with the standard curve according to the characteristic spectral wavelength and intensity corresponding to each heavy metal element.

7. The method for detecting pesticides, heavy metals and active ingredients in Chinese medicinal materials according to claim 1, characterized in that: In the step 4, a novel molecular imprinting-magnetic composite polymer column is selected for separation of effective components. One-half volume of the supernatant in step 1 is taken and slowly added to the molecular imprinting-magnetic composite polymer column. The loading flow rate is controlled to be 0.5 mL / min-1 mL / min. After the loading is completed, 5 mL-8 mL of methanol-water (volume ratio is 1:1) solution is used as eluent, and elution is performed at the same flow rate to further remove weakly bound impurities adsorbed on the polymer column. Then 5 mL-8 mL of methanol is selected as eluent to elute the target effective components adsorbed on the composite polymer column. The eluent is then slowly passed through the composite polymer column at a flow rate of 0.5 mL / min-1 mL / min, and the eluent is collected in a clean glass collection tube for standby use.

8. The method for detecting pesticides, heavy metals and active ingredients in Chinese medicinal materials according to claim 1, characterized in that: In the step 4, high performance liquid chromatography is used to detect the effective ingredients in the collected eluate. The specific operating parameter settings include chromatographic column selection, mobile phase setting, detector selection and parameter setting. The chromatographic column is a silica gel column (specification: 4.6 mm×250 mm, particle size: 5 um), the mobile phase is set to methanol-water, the volume ratio is 50-70:30-50, the flow rate is set to 1 mL / min, the column temperature is maintained at 30°C-35°C, the injection volume is 20 uL, the detector is a UV detector, and the detection wavelength is set according to its maximum absorption wavelength.

9. The method for detecting pesticides, heavy metals and active ingredients in Chinese medicinal materials according to claim 1, characterized in that: In the step five, the waste liquids generated in each link of pesticide residue detection, heavy metal detection and effective ingredient detection are classified and collected according to the characteristics of the components, and then the corresponding pretreatment means of reduced pressure distillation, activated carbon adsorption and neutralization reaction are used to reduce the pollution and treatment difficulty, detect pesticide residues, and recycle qualified organic solvents in the detection waste liquid. The rest are discharged after deep treatment to meet the standards. The heavy metal detection waste liquid is treated with an ion exchange resin adsorption column and then meets the discharge standards. The effective ingredient detection waste liquid is recycled after meeting the recycling standards.

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