A method for simultaneously detecting 16 phthalate plasticizers and its application

Abstract

The present invention discloses a method for simultaneously detecting 16 phthalate plasticizers, comprising the following steps: S1 prepares a tertiary mother liquor of a standard substance; S2 prepares the tertiary mother liquor of the standard substance into a system adaptability solution and a blank spiked solution; S3 prepares a blank solution and a test solution; S4 adds the system adaptability solution, the blank spiked solution, the blank solution and the test solution to an ultra-high performance liquid chromatography-mass spectrometry device for detection. The present invention uses an HPLC-MS device to detect 16 phthalates, and can detect 16 phthalate plasticizers simultaneously, with a high detection signal-to-noise ratio and a high accuracy rate. Using four plasticizer extracts and four blank extracts for control detection reduces background interference, improves the signal-to-noise ratio, and further improves the sensitivity of detection, and the analytical method has good specificity for the determination of 16 plasticizers in the extract.

Description

Technical Field

[0001] The present invention relates to the field of detection methods, and in particular to a method for simultaneously detecting 16 phthalate plasticizers and an application thereof. Background Art

[0002] Plasticizers are additives used in polymers to increase their plasticity. They are widely used in plastic packaging. As people become more aware of their health, they are increasingly concerned about the safety of plastic packaging. Plastic packaging is not only used for food but also for pharmaceutical packaging. When packaging pharmaceuticals, the acidity, alkalinity, and contents of the packaging can affect the plastic packaging, leading to plasticizer dissolution and potentially compromising the safety of food and pharmaceuticals. Therefore, developing a method to rapidly detect plasticizer dissolution from plastic packaging under different conditions is crucial.

[0003] Chinese invention patent CN 113075344A discloses a method for detecting plasticizers by thermal desorption-gas chromatography, wherein four phthalate compounds are separated by thermal desorption-gas chromatography, and the external standard method is used for quantitative qualitative and quantitative detection. The instrument is relatively simple, and the carrier gas is nitrogen. The detection is fast and environmentally friendly, but only the detection of four plasticizers can be achieved at the same time, and the detection is not comprehensive. Chinese invention patent CN102520091B discloses a method for detecting the content of plasticizers in solid samples by headspace solid phase microextraction gas chromatography-tandem mass spectrometry. The solid sample is mixed with an isotope internal standard, subjected to headspace solid phase microextraction extraction, and subjected to GC-MS / MS analysis. The detection is fast, efficient, and sensitive. However, no extraction and separation detection is performed under different environments, and the dissolution results of the plasticizer in the actual application environment cannot be verified. Summary of the Invention

[0004] In order to develop a method for rapidly detecting the dissolution of plasticizers from plastic packaging materials under different conditions, the first aspect of the present invention provides a method for simultaneously detecting 16 phthalate plasticizers, comprising the following steps:

[0005] S1 is used to prepare the tertiary mother solution of the standard substance;

[0006] S2 prepares the system adaptability solution and blank spike solution from the tertiary stock solution of the standard substance;

[0007] S3 prepares blank solution and test solution;

[0008] S4: Add the system suitability solution, blank spiked solution, blank solution and test solution to the ultra-high performance liquid chromatography-mass spectrometry equipment for detection.

[0009] As a preferred embodiment, the 16 phthalate plasticizers include dimethyl phthalate, diethyl phthalate, butyl benzyl phthalate, dibutyl phthalate, diisobutyl phthalate, di(2-ethylhexyl) phthalate, di-n-octyl phthalate, dinonyl phthalate, dicyclohexyl phthalate, dihexyl phthalate, di-4-methyl-2-pentyl phthalate, dibutoxyethyl phthalate, diethoxyethyl phthalate, di(n-)pentyl phthalate, di(2-methoxyethyl) phthalate, and diphenyl phthalate.

[0010] As a preferred embodiment, the standard substance is a mixed standard solution of 16 phthalate plasticizers, and the preparation method of the tertiary mother solution of the standard substance is to mix 50-150 μL of the mixed standard solution of 16 phthalate plasticizers with a diluent and dilute to 10 mL.

[0011] As a preferred embodiment, the tertiary mother solution of the standard substance is prepared by mixing 100 μL of a mixed standard solution of 16 phthalate plasticizers with a diluent and fixing the volume to 10 mL.

[0012] As a preferred embodiment, the system adaptability solution is prepared by mixing 10-50 μL of the tertiary stock solution of the standard substance with a diluent and fixing the volume to 10 mL.

[0013] As a preferred embodiment, the system adaptability solution is prepared by mixing 20 μL of the tertiary stock solution of the standard substance with a diluent and fixing the volume to 10 mL.

[0014] As a preferred embodiment, the blank spiked solution is prepared by mixing 50-150 μL of the tertiary stock solution of the standard substance with a diluent and fixing the volume to 10 mL.

[0015] As a preferred embodiment, the blank spiked solution is prepared by mixing 100 μL of the tertiary stock solution of the standard substance with a diluent and fixing the volume to 10 mL.

[0016] In a preferred embodiment, the test solution comprises a plasticizer extract and a blank extract. Prior to testing, the test solution is filtered through a fluorine membrane having a pore size of 0.1-0.5 μm. Preferably, the pore size of the fluorine membrane is 0.2 μm. Furthermore, preferably, the fluorine membrane is a PTFE membrane.

[0017] As a preferred embodiment, the plasticizer extract includes a water-soluble acidic extract, a water-soluble alkaline extract, a content extract, and an alcohol-water extract; the blank extract includes a blank water-soluble acidic extract, a blank water-soluble alkaline extract, a blank content extract, and a blank alcohol-water extract.

[0018] As a preferred embodiment, the solvent of the water-soluble acidic extract is 0.2M KCl aqueous solution (pH 3.0±0.1), the solvent of the water-soluble alkaline extract is 0.1M Na2HPO4 aqueous solution (pH 10.0±0.1), the solvent of the content extract is a simulated content liquid, and the solvent of the alcohol-water extract is ethanol aqueous solution (the volume ratio of ethanol and water is 50:50).

[0019] As a preferred embodiment, the blank water-soluble acidic extract is a 0.2M KCl aqueous solution (pH 3.0±0.1), the blank water-soluble alkaline extract is a 0.1M Na2HPO4 aqueous solution (pH 10.0±0.1), the blank content extract is a simulated content solution, and the blank alcohol-water extract is an ethanol aqueous solution (the volume ratio of ethanol and water is 50:50).

[0020] As a preferred embodiment, the chromatographic column of the ultra-high performance liquid chromatography-mass spectrometry apparatus is ZORBAX SB-C18, 2.1 mm × 150 mm, 3.5-micron or POROSHELL 120EC-C18, 3.0 mm × 50 mm, 2.7 μm. The column temperature of the chromatographic column is 40°C.

[0021] During the experiment, the inventors found that the use of high-performance liquid chromatography-mass spectrometry equipment to detect 16 phthalates can improve the signal-to-noise ratio and significantly improve the detection accuracy. The possible reason is speculated to be: using a chromatographic column with a filler particle size of 2.7 μm, the 16 phthalate plasticizers can be well separated in the longer chromatographic column. Multiple adsorption and desorption in the chromatographic column increase the peak distance of the 16 phthalate plasticizers and reduce the peak interference between the 16 phthalate plasticizers. In addition, the detection after the drug solution matrix further avoids the peak interference of the plasticizer substances.

[0022] As a preferred embodiment, the flow rate of the mobile phase of the ultra-high performance liquid chromatography-mass spectrometry device is 0.3 mL / min. The injection volume of the ultra-high performance liquid chromatography-mass spectrometry device is 5 μL.

[0023] As a preferred embodiment, the mobile phase of the ultra-high performance liquid chromatography in the ultra-high performance liquid chromatography-mass spectrometry apparatus comprises an aqueous ammonium acetate solution in phase A and methanol in phase B, wherein the molar concentration of the aqueous ammonium acetate solution is 3-8 mM. Preferably, the molar concentration of the aqueous ammonium acetate solution is 5 mM.

[0024] As a preferred embodiment, the mobile phase of the ultra high performance liquid chromatography in the ultra high performance liquid chromatography-mass spectrometry equipment adopts gradient elution, specifically 0 min: phase A 75 vol%, phase B 25 vol%; 2 min: phase A 50 vol%, phase B 50 vol%; 5 min: phase A 50 vol%, phase B 50 vol%; 6 min: phase A 20 vol%, phase B 80 vol%; 10 min: phase A 20 vol%, phase B 80 vol%; 10.1 min: phase A 10 vol%, phase B 90 vol%; 17 min: phase A 0 vol%, phase B 100 vol%; 21 min: phase A 0 vol%, phase B 100 vol%; 21.1 min: phase A 75 vol%, phase B 25 vol%; 25 min: phase A 75 vol%, phase B 25 vol%.

[0025] During the experiment, the inventors found that using ammonium acetate aqueous solution as mobile phase A and methanol as mobile phase B in liquid chromatography can improve the separation efficiency of liquid chromatography, achieve clear peak separation, and have high detection efficiency. The inventors speculated that the possible reason is that ammonium acetate and methanol use a gradient elution procedure to regulate the polarity of the mobile phase. Since the polarity of the 16 phthalates is not much different, a multi-level gradient elution procedure can be used to achieve clear separation of the 16 phthalates. In addition, the combination of mobile phases A and B achieves precise control of the mobile phase, improves peak elution efficiency, and enables liquid chromatography detection to be completed within 25 minutes, thereby improving detection efficiency.

[0026] As a preferred embodiment, the ion source of the mass spectrometer in the ultra-high performance liquid chromatography-mass spectrometry device is EIS, and the scanning ion mode of the mass spectrometer is MRM.

[0027] As a preferred embodiment, the mass spectrometry parameters in the ultra-high performance liquid chromatography-mass spectrometry equipment are as follows: sheath gas temperature of 350°C, sheath gas flow rate of 10-15 L / min, nebulizer temperature of 200°C, nebulizer gas flow rate of 5-10 L / min, spray pressure of 30-50 psi, spray voltage of 400-600 V, and capillary voltage of 3000-5000 V.

[0028] As a preferred embodiment, the mass spectrometry parameters in the ultra-high performance liquid chromatography-mass spectrometry equipment are as follows: sheath gas temperature of 350°C, sheath gas flow rate of 11 L / min, nebulizer temperature of 200°C, nebulizer gas flow rate of 9 L / min, spray pressure of 40 psi, spray voltage of 500 V, and capillary voltage of 4000 V.

[0029] As a preferred embodiment, the scanning parameters of the ultra-high performance liquid chromatography-mass spectrometry device are as follows:

[0030]

[0031]

[0032] As a preferred embodiment, the injection sequence of the ultra-high performance liquid chromatography-mass spectrometry device is as follows:

[0033]

[0034]

[0035] The blank content extract and the content extract are drug solution matrices with relatively complex components. In order to reduce test interference, they are tested after other extracts.

[0036] The second aspect of the present invention provides an application of a method for simultaneously detecting 16 phthalate plasticizers, which is applied to the detection of daily chemical product packaging, food packaging, and pharmaceutical packaging.

[0037] Compared with the prior art, the present invention has the following beneficial effects:

[0038] (1) The method for simultaneously detecting 16 phthalate plasticizers of the present invention uses high performance liquid chromatography-mass spectrometry equipment to detect 16 phthalates, and can simultaneously detect 16 phthalate plasticizers with a high signal-to-noise ratio and high accuracy.

[0039] (2) In the method for simultaneously detecting 16 phthalate plasticizers described in the present invention, an aqueous ammonium acetate solution is used as mobile phase A and methanol is used as mobile phase B in liquid chromatography, thereby improving the separation efficiency of liquid chromatography, achieving clear peak separation, and high detection efficiency.

[0040] (3) The method of the present invention for simultaneously detecting 16 phthalate plasticizers, wherein the plasticizer extracts include an acidic extract, an alkaline extract, a package contents extract, and an alcohol-water extract, can realize the dissolution detection of plasticizers under different conditions, and the detection is more comprehensive.

[0041] (4) The method for simultaneously detecting 16 phthalate plasticizers described in the present invention uses a mixed standard of 16 phthalate plasticizers for quantitative detection, thereby improving detection accuracy and sensitivity.

[0042] (5) The method for simultaneously detecting 16 phthalate plasticizers described in the present invention uses four plasticizer extracts and four blank extracts as control detection, which reduces background interference, improves the signal-to-noise ratio, and further improves the sensitivity of detection. In addition, this analytical method has good specificity for the determination of 16 plasticizers in the extracts. DETAILED DESCRIPTION

[0043] Example 1

[0044] A method for simultaneously detecting 16 phthalate plasticizers comprises the following steps:

[0045] S1 is used to prepare the tertiary mother solution of the standard substance;

[0046] S2 prepares the system adaptability solution and blank spike solution from the tertiary stock solution of the standard substance;

[0047] S3 prepares blank solution and test solution;

[0048] S4: Add the system suitability solution, blank spiked solution, blank solution and test solution to the ultra-high performance liquid chromatography-mass spectrometry equipment for detection.

[0049] The 16 phthalate plasticizers include dimethyl phthalate, diethyl phthalate, butyl benzyl phthalate, dibutyl phthalate, diisobutyl phthalate, di(2-ethylhexyl) phthalate, di-n-octyl phthalate, dinonyl phthalate, dicyclohexyl phthalate, dihexyl phthalate, di-4-methyl-2-pentyl phthalate, dibutoxyethyl phthalate, diethoxyethyl phthalate, di(n-)pentyl phthalate, di(2-methoxyethyl) phthalate, and diphenyl phthalate.

[0050] The tertiary mother solution of the standard substance is prepared by mixing 100 μL of a mixed standard solution of 16 phthalate plasticizers with a diluent and fixing the volume to 10 mL.

[0051] The system adaptability solution is prepared by mixing 20 μL of the tertiary stock solution of the standard substance with a diluent and diluting the volume to 10 mL.

[0052] The blank spike solution was prepared by mixing 100 μL of the tertiary stock solution of the standard substance with a diluent and then diluting the solution to 10 mL.

[0053] The test solution includes a plasticizer extract and a blank extract. The test solution needs to be filtered through a PTFE membrane before detection, and the pore size of the fluoromembrane is 0.2 μm.

[0054] The plasticizer extract is an alcohol-water extract; and the blank extract is a blank alcohol-water extract.

[0055] The solvent of the alcohol-water extract is an ethanol-water solution (the volume ratio of ethanol to water is 50:50); the blank alcohol-water extract is an ethanol-water solution (the volume ratio of ethanol to water is 50:50).

[0056] The plasticizer extract is obtained by soaking 1 g of a medical infusion bag in 2 mL of an ethanol aqueous solution, placing the bag in an oven at 70° C. and preserving the temperature for 72 hours.

[0057] The chromatographic column of the ultra-high performance liquid chromatography-mass spectrometry device is ZORBAX SB-C18, 2.1 mm×150 mm, 3.5-Micron, and the column temperature of the chromatographic column is 40°C.

[0058] The flow rate of the mobile phase of the ultra-high performance liquid chromatography-mass spectrometry device is 0.3 mL / min. The injection volume of the ultra-high performance liquid chromatography-mass spectrometry device is 5 μL.

[0059] The mobile phase of the ultra-high performance liquid chromatography in the ultra-high performance liquid chromatography-mass spectrometry device includes a phase A ammonium acetate aqueous solution and a phase B methanol, and the molar concentration of the ammonium acetate aqueous solution is 5 mM.

[0060] The mobile phase of the ultra-high performance liquid chromatography in the ultra-high performance liquid chromatography-mass spectrometry equipment adopts gradient elution, specifically 0 min: phase A 75 vol%, phase B 25 vol%; 2 min: phase A 50 vol%, phase B 50 vol%; 5 min: phase A 50 vol%, phase B 50 vol%; 6 min: phase A 20 vol%, phase B 80 vol%; 10 min: phase A 20 vol%, phase B 80 vol%; 10.1 min: phase A 10 vol%, phase B 90 vol%; 17 min: phase A 0 vol%, phase B 100 vol%; 21 min: phase A 0 vol%, phase B 100 vol%; 21.1 min: phase A 75 vol%, phase B 25 vol%; 25 min: phase A 75 vol%, phase B 25 vol%.

[0061] The ion source of the mass spectrometer in the ultra-high performance liquid chromatography-mass spectrometry device is EIS, and the scanning ion mode of the mass spectrometer is MRM.

[0062] The mass spectrometry parameters in the ultra-high performance liquid chromatography-mass spectrometry equipment are as follows: sheath gas temperature of 350°C, sheath gas flow rate of 11 L / min, nebulizer temperature of 200°C, nebulizer gas flow rate of 9 L / min, spray pressure of 40 psi, spray voltage of 500 V, and capillary voltage of 4000 V.

[0063] The scanning parameters of the ultra-high performance liquid chromatography-mass spectrometry device are as follows:

[0064]

[0065]

[0066] The injection sequence of the ultra-high performance liquid chromatography-mass spectrometry device is as follows:

[0067] name Number of injections blank solution 1 needle System suitability solution (front) 1 needle blank solution 1 needle Blank spike solution 1 needle blank solution 1 needle Blank water-soluble acidic extract 1 needle Blank water-soluble alkaline extract 1 needle Blank alcohol-water extract 1 needle Water-soluble acidic extract 1 needle Water-soluble alkaline extract 1 needle Alcohol-water extract 1 needle Blank content extract 1 needle Contents extract 1 needle blank solution 3-pin System suitability solution (post) 1 needle

[0068] The retention time of the plasticizer is as follows:

[0069] name Peak retention time / min Dimethyl phthalate 6.02 Diethyl phthalate 8.31 Butyl benzyl phthalate 10.81 Dibutyl phthalate 11.01 Diisobutyl phthalate 11.01 Bis(2-ethylhexyl) phthalate 16.07 Di-n-octyl phthalate 16.58 Dinonyl phthalate 17.85 Dicyclohexyl phthalate 13.08 Dihexyl phthalate 14.04 Di-4-methyl-2-pentyl phthalate 13.53 Dibutyloxyethyl phthalate 11.01 Diethoxyethyl phthalate 8.34 Di(n-)pentyl phthalate 12.91 Bis(2-methoxyethyl)phthalate 6.51 diphenyl phthalate 9.74

[0070] Performance Testing

[0071] 1. System stability before testing: The test results are shown in Table 1 below.

[0072] Table 1

[0073]

[0074] Conclusion: The instrument system has good stability before testing.

[0075] 2. System stability before, during and after testing: The test results are shown in Table 2 below.

[0076] Table 2

[0077]

[0078] Conclusion: The instrument response was stable before, during and after the test.

[0079] 3. Specificity test: The test results are shown in Table 3 below.

[0080] Table 3

[0081]

[0082] Conclusion: This analytical method has good specificity for the determination of 16 plasticizers in extracts.

[0083] 4. Signal-to-noise ratio of quantitation limit: The test results are shown in Table 4 below.

[0084] Table 4

[0085]

[0086]

[0087] Conclusion: The signal-to-noise ratio of the quantification limit is high and meets the standard of no less than 10.

Claims

1. A method for simultaneously detecting 16 phthalate plasticizers, characterized in that: The following steps are involved: S1 is a tertiary stock solution for preparing standard substances; S2 prepares the system adaptability solution and blank spike solution from the tertiary stock solution of the standard substance; S3 prepares blank solution and test solution; S4: Add the system suitability solution, blank spiked solution, blank solution and test solution into the ultra-high performance liquid chromatography-mass spectrometry equipment for detection.

2. The method for simultaneously detecting 16 phthalate plasticizers according to claim 1, characterized in that: The 16 phthalate plasticizers include dimethyl phthalate, diethyl phthalate, butyl benzyl phthalate, dibutyl phthalate, diisobutyl phthalate, di(2-ethylhexyl) phthalate, di-n-octyl phthalate, dinonyl phthalate, dicyclohexyl phthalate, dihexyl phthalate, di-4-methyl-2-pentyl phthalate, dibutoxyethyl phthalate, diethoxyethyl phthalate, di(n-)pentyl phthalate, di(2-methoxyethyl) phthalate, and diphenyl phthalate.

3. The method for simultaneously detecting 16 phthalate plasticizers according to claim 1, characterized in that: The standard substance is a mixed standard solution of 16 phthalate plasticizers. The preparation method of the tertiary mother solution of the standard substance is to mix 50-150 μL of the mixed standard solution of 16 phthalate plasticizers with a diluent and dilute to 10 mL.

4. The method for simultaneously detecting 16 phthalate plasticizers according to claim 1, characterized in that: The system adaptability solution is prepared by mixing 10-50 μL of the tertiary mother solution of the standard substance with a diluent and fixing the volume to 10 mL.

5. The method for simultaneously detecting 16 phthalate plasticizers according to claim 1, characterized in that: The blank spiked solution is prepared by mixing 50-150 μL of the tertiary mother solution of the standard substance with a diluent and fixing the volume to 10 mL.

6. The method for simultaneously detecting 16 phthalate plasticizers according to claim 1, characterized in that: The test solution includes a plasticizer extract and a blank extract. The test solution needs to be filtered through a fluorine membrane before detection. The pore size of the fluorine membrane is 0.1-0.5 μm.

7. The method for simultaneously detecting 16 phthalate plasticizers according to claim 1, characterized in that: The mobile phase of the ultra-high performance liquid chromatography in the ultra-high performance liquid chromatography-mass spectrometry device comprises an A-phase ammonium acetate aqueous solution and a B-phase methanol, and the molar concentration of the ammonium acetate aqueous solution is 3-8 mM.

8. The method for simultaneously detecting 16 phthalate plasticizers according to claim 7, characterized in that: The mobile phase of the ultra-high performance liquid chromatography in the ultra-high performance liquid chromatography-mass spectrometry device adopts gradient elution, specifically 0min: phase A 75vol%, phase B 25vol%; 2min: phase A 50vol%, phase B 50vol%; 5min: phase A 50vol%, phase B 50vol%; 6min: Phase A 20vol%, Phase B 80vol%; 10min: Phase A 20vol%, Phase B 80vol%; 10.1min: Phase A 10vol%, Phase B 90vol%; 17min: Phase A 0vol%, Phase B 100vol%; 21min: Phase A 0vol%, Phase B 100vol%; 21.1min: Phase A 75vol%, Phase B 25vol%; 25min: Phase A 75vol%, Phase B 25vol%.

9. The method for simultaneously detecting 16 phthalate plasticizers according to claim 1, characterized in that: The parameters of the mass spectrometer in the ultra-high performance liquid chromatography-mass spectrometry equipment are as follows: sheath gas temperature of 350°C, sheath gas flow rate of 10-15 L / min, nebulizer temperature of 200°C, nebulizer gas flow rate of 5-10 L / min, spray pressure of 30-50 psi, spray voltage of 400-600 V, and capillary voltage of 3000-5000 V.

10. An application of the method for simultaneously detecting 16 phthalate plasticizers according to any one of claims 1 to 9, characterized in that: Used in the inspection of daily chemical product packaging, food packaging, and pharmaceutical packaging.

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