CN112285250A - Method for measuring antioxidant content in rubber sealing gasket for food contact - Google Patents
Method for measuring antioxidant content in rubber sealing gasket for food contact Download PDFInfo
- Publication number
- CN112285250A CN112285250A CN202011124586.4A CN202011124586A CN112285250A CN 112285250 A CN112285250 A CN 112285250A CN 202011124586 A CN202011124586 A CN 202011124586A CN 112285250 A CN112285250 A CN 112285250A
- Authority
- CN
- China
- Prior art keywords
- extraction
- antioxidant
- solution
- rubber sealing
- food contact
- 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
- 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
- G01N30/88—Integrated analysis systems specially adapted therefor, not covered by a single one of the groups G01N30/04 - G01N30/86
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)
- Other Investigation Or Analysis Of Materials By Electrical Means (AREA)
Abstract
The invention discloses a method for measuring the content of an antioxidant in a rubber sealing gasket for food contact, and belongs to the technical field of high polymer material detection. The method comprises the steps of freezing and mechanically crushing the rubber sealing washer for food contact by using a full-automatic freezing and grinding machine, extracting for a certain time by using a methanol solution under the microwave condition, detecting by using a triple quadrupole liquid chromatography-mass spectrometer after high-speed centrifugation, and finally determining the content of 9 antioxidants in the rubber sealing washer sample for food contact by using an external standard method. The detection limit of the method is 0.16mg/kg, the quantification limit is 0.5mg/kg, 9 antioxidants have good linearity in the range of 0.01 mg/L-0.5 mg/L, the standard recovery rate is 73.1% -119.8%, the relative standard deviation is 0.7% -9.3%, and the method has good accuracy and repeatability.
Description
Technical Field
The invention relates to a method for measuring the content of an antioxidant in a rubber sealing gasket for food contact, belonging to the technical field of high polymer material detection.
Background
Antioxidants are a class of chemical substances, which are important additives added to high molecular weight materials, and when they are present in a polymer system in only small amounts, they retard or inhibit the oxidation process of the polymer, thereby preventing the aging of the polymer and prolonging its service life, also known as "anti-aging agents". "food contact materials and articles" means that the materials and articles will come into contact with food during use, including packaging materials, containers, and equipment used in food production, processing, transportation, storage, and use. The rubber sealing washer for food contact is widely applied to food processing machinery and plays a role in sealing. The common rubber sealing gasket material for food contact comprises ethylene propylene diene monomer, nitrile rubber, silicon rubber, fluororubber and the like. As a mechanical component, the rubber sealing gasket for food contact on one hand meets the requirement of a food processing system on sealing performance; on the other hand, it should also have good compatibility with the food, i.e. no extract which poses a safety risk can be introduced, or the extract level meets safety requirements. The antioxidant is used as a type of additive which is conventionally added in the rubber sealing gasket for food contact, the antioxidant is physically combined with rubber, and the antioxidant risks migrating into food in the process of contacting the rubber sealing gasket with the food; in addition, under the special working conditions of high temperature, high pressure, microwave and the like encountered in the production and processing processes of the food, the migration of the antioxidant to the food can be accelerated. Therefore, attention needs to be paid to the actual migratable amount of antioxidant in the rubber sealing gasket for food contact.
The problems existing in the prior art are as follows: 1. the sample preparation link usually adopts a shearing method, which is time-consuming, labor-consuming and insufficient in extraction, and the extraction also usually adopts relatively time-consuming extraction means such as ultrasonic and reflux. 2. The detection target species are limited to one to three specific commonly used antioxidant targets, the number of antioxidants actually added in the rubber sealing gasket is large, multiple target species are needed to be respectively injected, multiple tests are needed to complete qualitative screening and quantitative analysis of potential extractables, systematicness is lacked, and detection efficiency is low. 3. The liquid chromatography and the gas chromatography are adopted, the detection time is long, the efficiency is low, and the qualitative process is slightly fussy.
Disclosure of Invention
Aiming at the problems of complex pretreatment, few types of detection target objects, low detection efficiency and the like in the prior art, the invention provides the method for detecting 9 antioxidants in the rubber sealing gasket for food contact.
The first purpose of the invention is to provide a pretreatment method for extracting antioxidant from a rubber sealing gasket for food contact, which comprises the steps of crushing the rubber sealing gasket for food contact to obtain rubber powder, and adding methanol for extraction to obtain an extracting solution; the volume mass ratio of the methanol to the rubber powder is (1-25): (0.1-1), mL/g.
In one embodiment of the invention, the extraction method comprises microwave extraction, ultrasonic extraction or reflux extraction.
In one embodiment of the present invention, the microwave extraction conditions are: the microwave power is 200-800W, the microwave temperature is 40-70 ℃, and the extraction time is 10-40 min.
In one embodiment of the present invention, the ultrasonic extraction conditions are: the ultrasonic frequency is 20-50KHz, the ultrasonic temperature is 40-70 deg.C, and the extraction time is 20-60 min.
In one embodiment of the present invention, the reflux extraction conditions are: the extraction temperature is 40-70 ℃, and the extraction time is 30-120 min.
In one embodiment of the invention, the method comprises the steps of: 1) mechanically pulverizing the sealing washer to be detected by a full-automatic freezing grinder, weighing 0.2-2g of rubber powder, and performing microwave extraction with 2-50mL of methanol solution at 40-70 ℃ for 10-40 min;
2) obtaining an extracting solution, leaching the rubber powder with 2-10mL of methanol solution, repeating the leaching, combining the extracting solution and the leaching solution, transferring the mixture into a volumetric flask, and performing constant volume with methanol;
3) and (3) taking the solution with constant volume into a centrifugal tube, and centrifuging at a high speed of 10000-16000r/min for 2-10min to obtain the solution to be detected.
In one embodiment of the invention, the antioxidant is one or more of antioxidant ZKF, antioxidant 259, antioxidant 1035, antioxidant 300, antioxidant 2246, antioxidant 425, antioxidant 1520, antioxidant 1098, and antioxidant 565.
The second purpose of the invention is to provide an application of the pretreatment method in food quality detection.
The third purpose of the invention is to provide a method for measuring the antioxidant content in the rubber sealing gasket for food contact, which comprises the steps of pretreating the rubber sealing gasket for food contact by adopting the method to obtain an extracting solution, and then detecting the extracting solution by adopting a triple quadrupole rod LC-MS; and finally, measuring the content of the antioxidant in the rubber sealing gasket for food contact by adopting an external standard method.
In one embodiment of the invention, the antioxidant is one or more of antioxidant ZKF, antioxidant 259, antioxidant 1035, antioxidant 300, antioxidant 2246, antioxidant 425, antioxidant 1520, antioxidant 1098, and antioxidant 565.
In one embodiment of the invention, the chromatographic column in the triple quadrupole liquid chromatography-mass spectrometry method is Waters ACQUITY UPLC BEH C18And (3) carrying out chromatographic column, wherein the mobile phase A is acetonitrile, and the mobile phase B is a 5mmol/L ammonium acetate aqueous solution.
In one embodiment of the present invention, the conditions of the triple quadrupole liquid chromatography-mass spectrometry method are as follows: the column temperature is 20-45 ℃; the detection wavelength is 276 nm; the flow rate is 0.1-2 mL/min; the sample volume is 2-20 μ L.
In one embodiment of the invention, the mobile phase elution procedure of the triple quadrupole liquid chromatography-mass spectrometry method is 0-2 min, 20% A; 2-4 min, 20% A-90% A; 4-4.5 min, 90-99% A; 4.5-11.5 min, 99% A; 11.5-12 min, 99-20% A; 12-15 min, 20% A.
In one embodiment of the present invention, the conditions of the triple quadrupole liquid chromatography-mass spectrometry method are as follows: an electrospray ion source; selecting a reactive scanning mode (SRM); capillary temperature: 200 ℃ and 350 ℃; auxiliary gas heating temperature: at 50 ℃.
In one embodiment of the present invention, the process of drawing the standard curve is as follows:
1)9 antioxidant standard stock solutions (1000mg/L) were prepared: a proper amount of 9 antioxidants are accurately weighed, and methanol is used as a solvent to prepare a standard stock solution with the concentration of 1000 mg/L.
2) Mixing standard intermediate solution (10mg/L, 1mg/L) to prepare: an appropriate amount of 9 antioxidant standard stock solutions (1000mg/L) were accurately pipetted and diluted with methanol to a concentration of 10 mg/L. In addition, an appropriate amount of 9 antioxidant standard intermediate solutions (10mg/L) were accurately transferred and diluted with methanol to a concentration of 1 mg/L.
3) Preparing a mixed standard working solution series: accurately transferring a proper amount of mixed standard intermediate solution (10mg/L and 1mg/L), diluting with methanol to obtain mixed standard working solution series with antioxidant concentrations of 0.01mg/L, 0.02mg/L, 0.05mg/L, 0.1mg/L, 0.2mg/L and 0.5mg/L respectively, and testing.
4) Drawing a standard curve: measuring the standard working solution series according to the selected triple quadrupole rod LC-MS conditions; respectively drawing standard working curves by taking the concentration of each antioxidant in the standard working solution as a horizontal coordinate and taking the corresponding chromatographic peak area as a vertical coordinate to obtain a linear equation;
triple quadrupole LC-MS conditions: waters ACQUITY UPLC BEH C18A chromatographic column; the mobile phase A is acetonitrile, and the mobile phase B is 5mmol/L ammonium acetate aqueous solution; the column temperature is 20-45 ℃; the detection wavelength is 276 nm; the flow rate is 0.1-2 mL/min; the sample volume is 2-20 mu L; eluting the mobile phase for 0-2 min by 20% A; 2-4 min, 20% A-90% A; 4-4.5 min, 90-99% A; 4.5-11.5 min, 99% A; 11.5-12 min, 99-20% A; 12-15 min, 20% A; an electrospray ion source; selecting a reactive scanning mode (SRM); capillary temperature: 200 ℃ and 350 ℃; auxiliary gas heating temperature: at 50 ℃.
In one embodiment of the present invention, the detection of the prepared test solution by the triple quadrupole liquid chromatograph requires:
1) mechanically pulverizing the sealing washer to be detected by a full-automatic freezing grinder, weighing 0.2-2g of rubber powder, and performing microwave extraction with 2-50mL of methanol solution at 40-70 ℃ for 10-40 min;
2) obtaining an extracting solution, leaching the rubber powder with 2-20mL of methanol solution, repeating the leaching, combining the extracting solution and the leaching solution, transferring the mixture into a volumetric flask, and performing constant volume with methanol;
3) and (3) taking the solution with constant volume into a centrifuge tube, centrifuging at a high speed of 10000-16000r/min for 2-10min, repeating once, and detecting the centrifugate by adopting the triple quadrupole rod liquid mass spectrometry.
In one embodiment of the present invention, the concentration of antioxidant in the sample is calculated as follows:
in the formula:
c-concentration of a certain antioxidant in the sample in milligrams per kilogram (mg/kg);
y is the area of a certain antioxidant chromatogram peak in the sample;
a is the slope of a standard curve for a certain antioxidant in a sample;
b-the intercept of a standard curve for a certain antioxidant in a sample;
50-conversion factor.
The invention has the beneficial effects that:
1) according to the invention, the rubber gasket for food contact is crushed by adopting the full-automatic freezing grinder, compared with a shearing method, the pretreatment process of the rubber gasket is greatly simplified, and time and labor are saved. A relatively green microwave methanol extraction pretreatment method is established, and compared with extraction methods such as ultrasonic extraction and reflux extraction, the method has the advantages of less extraction solvent, short extraction time and the like.
2) The invention adopts a triple quadrupole liquid chromatograph-mass spectrometer to simultaneously detect 9 antioxidants in the rubber sealing washer for food contact, provides a high-flux detection means for systematically screening the antioxidants, and does not report a method for simultaneously detecting the 9 antioxidants in the rubber sealing washer for food contact by adopting the triple quadrupole liquid chromatograph-mass spectrometer in related documents.
3) The method has the advantages that the limit of quantification is 0.5mg/kg, the limit of detection is 0.16mg/kg, the limit of detection of an instrument is 0.6ppb, and the sensitivity is high; the 9 antioxidants have good linearity within the range of 0.01 mg/L-0.5 mg/L, the standard recovery rate is 73.1-119.8%, and the relative standard deviation is 0.7-9.3%. Meanwhile, only 15 minutes are needed for detecting 8 antioxidants, and the screening efficiency is greatly improved. The antioxidant in the sample is not easy to volatilize and lose, has the advantages of convenient operation, good linear range, high sensitivity, high detection efficiency and the like, and can meet the requirement of high-flux detection of the antioxidant in the rubber sealing washer for food contact.
Drawings
Fig. 1 is a selected ion flow diagram of 9 antioxidants in a 0.5ppm mixed control solution as provided in example 1, wherein antioxidant 300, antioxidant 1098, antioxidant 2246, antioxidant 425, antioxidant ZKF, antioxidant 1035, antioxidant 259, antioxidant 1520, and antioxidant 565 are shown in sequence from top to bottom.
Figure 2 is a selected ion flow diagram of 3 antioxidants under the conditions of elution procedure 2 provided in example 6, wherein antioxidant 1035, antioxidant 1520, and antioxidant 565 are in sequence from top to bottom.
Figure 3 is a selected ion flow diagram of antioxidant 565 under the conditions of elution procedure 3 provided in example 6.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail with reference to the following embodiments. It should be understood that the specific embodiments described herein are for the purpose of illustrating the invention better and are not to be construed as limiting the invention.
Example 1: establishment of a Standard Curve
1)9 antioxidant standard stock solutions (1000mg/L) were prepared: a proper amount of 9 antioxidants are accurately weighed, and methanol is used as a solvent to prepare a standard stock solution with the concentration of 1000 mg/L.
2) Mixing standard intermediate solution (10mg/L, 1mg/L) to prepare: an appropriate amount of 9 antioxidant standard stock solutions (1000mg/L) were accurately pipetted and diluted with methanol to a concentration of 10 mg/L. In addition, an appropriate amount of 9 antioxidant standard intermediate solutions (10mg/L) were accurately transferred and diluted with methanol to a concentration of 1 mg/L.
3) Preparing a mixed standard working solution series: accurately transferring a proper amount of mixed standard intermediate solution (10mg/L and 1mg/L), diluting with methanol to obtain mixed standard working solution series with antioxidant concentrations of 0.01mg/L, 0.02mg/L, 0.05mg/L, 0.1mg/L, 0.2mg/L and 0.5mg/L respectively, and testing.
4) Drawing a standard curve: the standard working fluid series was measured according to the selected triple quadrupole LC-MS conditions as follows: waters ACQUITY UPLC BEH C18A column; the mobile phase A is acetonitrile, and the mobile phase B is 5mmol/L ammonium acetate aqueous solution; the column temperature is 45 ℃; the detection wavelength is 276 nm; the flow rate is 0.3 mL/min; the sample injection amount is 5 mu L; an electrospray ion source; selecting a reactive scanning mode (SRM); capillary temperature: 350 ℃; auxiliary gas heating temperature: at 50 ℃. The mobile phase elution conditions are shown in table 1. Mass spectrometric detection of parent ions, daughter ions, collision energy and retention time are shown in table 2.
TABLE 1 mobile phase gradient elution conditions
TABLE 29 antioxidant Mass Spectrometry parameters
And respectively drawing standard working curves by taking the concentration of each antioxidant in the standard working solution as an abscissa and the corresponding chromatographic peak area as an ordinate to obtain a linear equation shown in table 3. A standard solution selection ion flow diagram is shown in figure 1.
TABLE 3 Standard Curve, Linear Range, correlation coefficient, instrumental quantitation Limit and instrumental detection Limit for each antioxidant
Example 2: pretreatment method for extracting antioxidant in rubber sealing gasket for food contact
1) Performing freeze mechanical pulverization on the sealing washer to be detected by adopting a full-automatic freeze grinder, weighing 0.5g of rubber powder, and performing microwave extraction for 15min at 50 ℃ by using 10mL of methanol solution;
2) obtaining an extracting solution, leaching the rubber powder with 5mL of methanol solution, repeating the leaching, combining the extracting solution and the leaching solution, transferring the mixture into a volumetric flask, and performing constant volume with methanol;
3) and (3) putting the solution with constant volume into a centrifuge tube, centrifuging at a high speed of 16000r/min for 5min, repeating once, and detecting the centrifugate by adopting the triple quadrupole liquid chromatography-mass spectrometry.
Example 3: selection of sample pretreatment method
Provides a rapid, simple and green extraction means for screening the antioxidant in the rubber sealing washer for food contact. The invention firstly compares three extraction methods of microwave extraction, ultrasonic extraction and reflux extraction, and then compares two extraction solvents of acetone and methanol.
1. Extraction was performed with reference to the method of example 2, except that microwave extraction was replaced with ultrasonic extraction and reflux extraction, wherein the ultrasonic extraction method was: mechanically pulverizing the sealing washer to be detected by a full-automatic freezing grinder, weighing 0.5g of rubber powder, and ultrasonically extracting with 10mL of methanol solution at 50 ℃ for 40 min;
the reflux extraction method comprises the following steps: the sealing washer to be detected is subjected to freezing mechanical crushing by a full-automatic freezing grinder, 0.5g of rubber powder is weighed, and reflux extraction is carried out for 60min at 65 ℃ by using 10mL of methanol solution. The extraction rate of each antioxidant obtained is shown in table 4.
2. The extraction was carried out by referring to the method of example 2 except that acetone was substituted for methanol and the other conditions were the same as in example 2, and the extraction rates of the respective antioxidants obtained are shown in table 5.
TABLE 4 extraction rate of microwave, ultrasonic and reflux extraction of methanol
TABLE 5 extraction rates of acetone microwave extraction, ultrasonic extraction and reflux extraction
As can be seen from tables 4 and 5, the extraction rates of 9 antioxidants were not very different in the 3 extraction methods when acetone was used as the extraction solvent. The recovery rate of the reflux extraction is relatively lower than that of the ultrasonic extraction and the microwave extraction, and compared with the ultrasonic extraction, the extraction of the microwave extraction only needs 15 min. When the extraction solvent is methanol, the solvent effect existing in the detection of other solvents is eliminated, the extraction rates of 8 antioxidants except the antioxidant 300 are higher than that of the solvent which is acetone, and the extraction rate under microwave extraction is obviously higher than that of reflux extraction and ultrasonic extraction. Considering the extraction rate and extraction efficiency of 9 antioxidants together, the selected extraction solvent is methanol, the extraction method is microwave extraction, and the extraction rates of the final antioxidant ZKF, the antioxidant 259, the antioxidant 1035, the antioxidant 300, the antioxidant 2246, the antioxidant 425, the antioxidant 1520, the antioxidant 1098 and the antioxidant 565 are 75.0%, 82.0%, 101.0%, 36.9%, 58.8%, 59.0%, 73.0%, 25.0% and 82.0%, respectively.
Example 4: method for measuring antioxidant in rubber sealing gasket for food contact
1) Performing freeze mechanical pulverization on the sealing washer to be detected by adopting a full-automatic freeze grinder, weighing 0.5g of rubber powder, and performing microwave extraction for 15min at 50 ℃ by using 10mL of methanol solution;
2) obtaining an extracting solution, leaching the rubber powder with 5mL of methanol solution, repeating the leaching, combining the extracting solution and the leaching solution, transferring the mixture into a volumetric flask, and performing constant volume with methanol;
3) and (3) putting the solution with constant volume into a centrifuge tube, centrifuging at a high speed of 16000r/min for 5min, repeating once, and detecting the centrifugate by adopting the triple quadrupole liquid chromatography-mass spectrometry.
Triple quadrupole LC-MS conditions: waters ACQUITY UPLC BEH C18A chromatographic column; the mobile phase A is acetonitrile, and the mobile phase B is 5mmol/L ammonium acetate aqueous solution; the column temperature is 45 ℃; the detection wavelength is 276 nm; the flow rate is 0.3 mL/min; the sample injection amount is 5 mu L; an electrospray ion source; selecting a reactive scanning mode (SRM); capillary temperature: 350 ℃; auxiliary gas heating temperature: at 50 ℃. The mobile phase elution conditions are shown in table 1. Mass spectrometric detection of parent ions, daughter ions, collision energy and retention time are shown in table 2.
4) And (3) qualitative analysis: the Retention Time (RT) of the target in the sample is compared to a standard sample to characterize. The retention time of the target compound in the sample should be within ± 2.5% of the retention time in the standard series of solutions.
5) Quantitative analysis:
the concentration of antioxidant in the sample was calculated according to the following formula, with the calculation retaining four significant digits:
in the formula:
c-concentration of a certain antioxidant in the sample in milligrams per kilogram (mg/kg);
y is the area of a certain antioxidant chromatogram peak in the sample;
a is the slope of a standard curve for a certain antioxidant in a sample;
b-the intercept of a standard curve for a certain antioxidant in a sample;
50-conversion factor.
Example 5: selection of chromatography columns
The invention compares ACQUITY UPLC BEH C18(1.7μm，100×2.1mm)、Agilent C18Eclipse plus (3.5 μm, 100X 3.0mm) and SunAire C8Separation effect on 9 antioxidants (5 μm, 250X 4.6 mm). Using SunAire C8In the case of a column, the antioxidant 259 and the antioxidant ZKF have a short retention time and cannot be completely separated, which may be due to C8The column carbon chain is short, and the retention property to weak polar or non-polar substances is poor; agilent C18Eclipse plus and ACQUITY UPLC BEH C18The carbon chain of the chromatographic column is longer, the retention property of the weak polar or non-polar substances is better, experiments show that when the chromatographic column is used for separation, the chromatographic peak of partial antioxidant has tailing, and the chromatographic column is replaced by the acid UPLC BEH C18Later, the peak shapes of the 7 antioxidants separated by different channels were symmetrical and beautiful, probably due to the ACQUITY UPLC BEH C18The chromatographic column has smaller particle size and higher column efficiency. Thus, ACQUITY UPLC BEH C is selected18The column was tested.
Example 6: selection of elution conditions
The antioxidant content of the rubber sealing gasket for food contact was measured by the method of example 5, except that the elution procedure was changed as follows:
the first condition is as follows: 0-2 min, 20% A; 2-4 min, 20% A-90% A; 4-4.5 min, 90-99% A; 4.5-11.5 min, 99% A; 11.5-12 min, 99-20% A; 12-15 min, 20% A;
and a second condition: 0-15 min, 75% A;
and (3) carrying out a third condition: 0-2 min, 10% A; 2-4.5 min, 10-99% A; 4.5-11.5 min, 99% A; 11.5-12 min, 99-10% A; 12-15 min, 10% A.
When isocratic elution under condition 2 is used for detection, the antioxidant 1035, the antioxidant 1520 and the antioxidant 565 cannot realize separation, qualitative and quantitative, and an ion flow diagram is selected and shown in figure 2. When the detection is performed by changing to the gradient elution of the condition 3, an interference peak with a stronger signal appears in the antioxidant 565 during the detection, and a selected ion flow diagram of the antioxidant 565 is shown in figure 3. Therefore, after the initial proportion of the organic phase is adjusted and the gradient elution of the condition 1 is replaced, the 9 substances can be well separated, the peak shape is sharp, the symmetry and the beauty are realized, and the selected ion flow diagram of the 9 substances is shown in the attached figure 1.
Example 7: methodology validation
1) Method detection limit, method quantitation limit, linearity and range
The method detection limits and method quantitation limits for the 9 antioxidants are shown in table 6, and the linearity and range are shown in table 3.
TABLE 69 Instrument detection limits, Instrument quantitation limits, method detection limits, and method quantitation limits for antioxidants
2) Accuracy and repeatability
And (3) testing the precision standard addition recovery rate:
and adding low, medium and high antioxidant standard solutions with three concentrations into the negative blank sample respectively, preparing 6 parts of sample in parallel at each concentration, and calculating the recovery rate and precision of the sample, wherein the results are shown in Table 7. The recovery rate of the added standard is between 73.1% and 119.8%, the relative standard deviation is between 0.7% and 9.3%, and the method has good accuracy and repeatability.
Table 7 recovery and precision experimental results (n ═ 6)
Example 8: application of detecting content of 9 antioxidants in rubber sealing gasket for contact of 8 commercially available foods
1) Performing freeze mechanical pulverization on the sealing washer to be detected by adopting a full-automatic freeze grinder, weighing 0.5g of rubber powder, and performing microwave extraction for 15min at 50 ℃ by using 10mL of methanol solution;
2) obtaining an extracting solution, leaching the rubber powder with 5mL of methanol solution, repeating the leaching, combining the extracting solution and the leaching solution, transferring the mixture into a volumetric flask, and performing constant volume with methanol;
3) and (3) putting the solution with constant volume into a centrifuge tube, centrifuging at a high speed of 16000r/min for 5min, repeating once, and detecting the centrifugate by adopting the triple quadrupole liquid chromatography-mass spectrometry.
Triple quadrupole LC-MS conditions: waters ACQUITY UPLC BEH C18A chromatographic column; the mobile phase A is acetonitrile, and the mobile phase B is 5mmol/L ammonium acetate aqueous solution; the column temperature is 45 ℃; the detection wavelength is 276 nm; the flow rate is 0.3 mL/min; the sample injection amount is 5 mu L; an electrospray ion source; selecting a reactive scanning mode (SRM); capillary temperature: 350 ℃; auxiliary gas heating temperature: at 50 ℃. The mobile phase elution conditions are shown in table 1. Mass spectrometric detection of parent ions, daughter ions, collision energy and retention time are shown in table 2.
4) And (3) qualitative analysis: the Retention Time (RT) of the target in the sample is compared to a standard sample to characterize. The retention time of the target compound in the sample should be within ± 2.5% of the retention time in the standard series of solutions.
5) And finally, calculating the antioxidant concentration of 8 rubber sealing gasket samples for food contact according to a curve formula to obtain the concentration of a certain antioxidant in each sample. The results of the antioxidant test in the 8 kinds of rubber seal gaskets for food contact, after unit conversion, are shown in Table 8.
TABLE 88 results of antioxidant test (mg/kg) on rubber gasket samples for food contact
Description of the drawings: n.d. no detection (below the method detection/quantitation limit)
Although the present invention has been described with reference to the preferred embodiments, it should be understood that various changes and modifications can be made therein by those skilled in the art without departing from the spirit and scope of the invention as defined in the appended claims.
Claims (10)
1. A pretreatment method for extracting an antioxidant from a rubber sealing gasket for food contact is characterized in that the method comprises the steps of crushing the rubber sealing gasket for food contact to obtain rubber powder, and adding methanol for extraction to obtain an extracting solution; the volume mass ratio of the methanol to the rubber powder is (1-25): (0.1-1), mL/g.
2. The pretreatment method of claim 1, wherein the extraction method comprises microwave extraction, ultrasonic extraction, or reflux extraction.
3. The pretreatment method according to claim 2, wherein the microwave extraction conditions are: the microwave power is 200-800W, the microwave temperature is 40-70 ℃, and the extraction time is 10-40 min.
4. The pretreatment method according to claim 2, wherein the ultrasonic extraction conditions are: the ultrasonic frequency is 20-50KHz, the ultrasonic temperature is 40-70 deg.C, and the extraction time is 20-60 min.
5. The pretreatment method according to claim 2, wherein the reflux extraction conditions are: the extraction temperature is 40-70 ℃, and the extraction time is 30-120 min.
6. A pretreatment method according to any one of claims 1 to 3, characterized in that the method comprises the steps of: 1) mechanically pulverizing the sealing washer to be detected by a full-automatic freezing grinder, weighing 0.2-2g of rubber powder, and performing microwave extraction with 2-50mL of methanol solution at 40-70 ℃ for 10-40 min;
2) obtaining an extracting solution, leaching the rubber powder with 2-10mL of methanol solution, repeating the leaching, combining the extracting solution and the leaching solution, transferring the mixture into a volumetric flask, and performing constant volume with methanol;
3) and (3) taking the solution with constant volume into a centrifugal tube, and centrifuging at a high speed of 10000-16000r/min for 2-10min to obtain the solution to be detected.
7. Use of the pretreatment method of any one of claims 1 to 6 for food quality testing.
8. A method for measuring the content of an antioxidant in a rubber sealing gasket for product contact is characterized in that the method comprises the steps of pretreating the rubber sealing gasket for food contact by the pretreatment method of any one of claims 1 to 6 to obtain an extracting solution, and detecting the extracting solution by a triple quadrupole liquid chromatography-mass spectrometer; and finally, measuring the content of the antioxidant in the rubber sealing gasket for food contact by adopting an external standard method.
9. The detection method according to claim 8, wherein the chromatographic column in the triple quadrupole rod LC-MS method is Waters ACQUITY UPLC BEH C18And (3) carrying out chromatographic column, wherein the mobile phase A is acetonitrile, and the mobile phase B is a 5mmol/L ammonium acetate aqueous solution.
10. The detection method according to claim 8 or 9, wherein the conditions of the triple quadrupole liquid chromatography-mass spectrometry method are as follows: the column temperature is 20-45 ℃; the detection wavelength is 276 nm; the flow rate is 0.1-2 mL/min; the sample volume is 2-20 mu L; the mobile phase elution procedure of the triple quadrupole liquid chromatography-mass spectrometry method is 0-2 min and 20% A; 2-4 min, 20% A-90% A; 4-4.5 min, 90-99% A; 4.5-11.5 min, 99% A; 11.5-12 min, 99-20% A; 12-15 min, 20% A.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011124586.4A CN112285250A (en) | 2020-10-20 | 2020-10-20 | Method for measuring antioxidant content in rubber sealing gasket for food contact |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011124586.4A CN112285250A (en) | 2020-10-20 | 2020-10-20 | Method for measuring antioxidant content in rubber sealing gasket for food contact |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN112285250A true CN112285250A (en) | 2021-01-29 |
Family
ID=74424045
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011124586.4A Pending CN112285250A (en) | 2020-10-20 | 2020-10-20 | Method for measuring antioxidant content in rubber sealing gasket for food contact |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112285250A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114047280A (en) * | 2021-10-21 | 2022-02-15 | 苏州药明康德新药开发有限公司 | Method for detecting content of non-volatile unknown substances in medical instrument leaching liquor |
| CN115015416A (en) * | 2022-05-31 | 2022-09-06 | 辽宁省检验检测认证中心 | Method for synchronously measuring content of five antioxidants in medicinal rubber plug |
| CN115856118A (en) * | 2022-11-17 | 2023-03-28 | 山东玲珑轮胎股份有限公司 | Method for measuring content of auxiliary agent in pre-dispersed rubber auxiliary agent masterbatch particles |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101279067A (en) * | 2008-02-28 | 2008-10-08 | 张会林 | Preparation of shaolin plaster for rheumatism and wound and quality control method |
| CN102380980A (en) * | 2011-07-27 | 2012-03-21 | 江南大学 | Self-purifying textile and processing method thereof |
| CN104330504A (en) * | 2014-11-21 | 2015-02-04 | 东莞市中鼎检测技术有限公司 | Method for determining content of bisphenol A in food contact material |
| CN104502468A (en) * | 2014-11-26 | 2015-04-08 | 广州广电计量检测股份有限公司 | Detection method for ethlenethiourea in plastic products |
| CN109438784A (en) * | 2018-12-24 | 2019-03-08 | 常州轻工职业技术学院 | Primary spring fire-retardant rubber material based on railcar |
| CN109633070A (en) * | 2019-02-26 | 2019-04-16 | 江阴市产品质量监督检验所 | A kind of method that High Performance Liquid Chromatography detects nonyl phenol and bisphenol-A in Food Plastic Packaging Material |
-
2020
- 2020-10-20 CN CN202011124586.4A patent/CN112285250A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101279067A (en) * | 2008-02-28 | 2008-10-08 | 张会林 | Preparation of shaolin plaster for rheumatism and wound and quality control method |
| CN102380980A (en) * | 2011-07-27 | 2012-03-21 | 江南大学 | Self-purifying textile and processing method thereof |
| CN104330504A (en) * | 2014-11-21 | 2015-02-04 | 东莞市中鼎检测技术有限公司 | Method for determining content of bisphenol A in food contact material |
| CN104502468A (en) * | 2014-11-26 | 2015-04-08 | 广州广电计量检测股份有限公司 | Detection method for ethlenethiourea in plastic products |
| CN109438784A (en) * | 2018-12-24 | 2019-03-08 | 常州轻工职业技术学院 | Primary spring fire-retardant rubber material based on railcar |
| CN109633070A (en) * | 2019-02-26 | 2019-04-16 | 江阴市产品质量监督检验所 | A kind of method that High Performance Liquid Chromatography detects nonyl phenol and bisphenol-A in Food Plastic Packaging Material |
Non-Patent Citations (4)
| Title |
|---|
| CHENGFA LI ET AL: "Simultaneous Determination of Antioxidants and Ultraviolet Absorbers by Ultra-Performance Liquid Chromatography in Food Simulants", 《FOOD ANAL. METHODS 》 * |
| 李婷婷: "药用丁基胶塞与头孢唑林钠相容性研究", 《中国优秀硕士学位论文全文数据库 医药卫生科技辑》 * |
| 王成云 等: "超高效液相色谱/静电场轨道阱高分辨质谱法快速筛查塑料食品接触材料中抗氧剂", 《塑料助剂》 * |
| 程燕 等: "《生命科学 实验仪器设备与使用》", 31 August 2014, 科学技术文献出版社 * |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114047280A (en) * | 2021-10-21 | 2022-02-15 | 苏州药明康德新药开发有限公司 | Method for detecting content of non-volatile unknown substances in medical instrument leaching liquor |
| CN115015416A (en) * | 2022-05-31 | 2022-09-06 | 辽宁省检验检测认证中心 | Method for synchronously measuring content of five antioxidants in medicinal rubber plug |
| CN115856118A (en) * | 2022-11-17 | 2023-03-28 | 山东玲珑轮胎股份有限公司 | Method for measuring content of auxiliary agent in pre-dispersed rubber auxiliary agent masterbatch particles |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN112285250A (en) | Method for measuring antioxidant content in rubber sealing gasket for food contact | |
| CN105929052B (en) | The method of the method for building up and detection antioxidant and preservative in antioxidant and preservative high resolution mass spectrum data library | |
| CN111289637B (en) | Method for detecting patulin in apple juice | |
| CN108344822B (en) | Analysis method for determining residues of various additives in food contact plastic products | |
| Wu et al. | Combination of solid‐phase micro‐extraction and direct analysis in real time‐Fourier transform ion cyclotron resonance mass spectrometry for sensitive and rapid analysis of 15 phthalate plasticizers in beverages | |
| CN111060616A (en) | Detection method for nitrosamine impurities in valsartan preparation | |
| CN102338789A (en) | Fast instrumental analysis method for aflatoxins in foods | |
| CN109828051B (en) | Method for detecting toxic compound | |
| CN110082469B (en) | Method for measuring content of trace alcohols and ketones in transformer insulating oil | |
| Shimada et al. | Evaluation of mass discrimination effects in the quantitative analysis of polydisperse polymers by matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry using uniform oligostyrenes | |
| CN108956813B (en) | Offline supercritical extraction-supercritical chromatography-mass spectrometry combined detection method for polyphenols | |
| CN113075325B (en) | Method for simultaneously measuring contents of 8 index components in cynanchum wilfordii | |
| CN108982703B (en) | Liquid chromatography-mass spectrometry detection method for polyphenol substances | |
| CN105938102B (en) | Method for rapidly determining pesticide residues in fruits and vegetables by chemical color development method | |
| CN108181393A (en) | The detection method of ethoxy perhydro-s-triazine in a kind of plastic products | |
| CN108956812B (en) | Method for detecting water-soluble organic chloride pesticide residue in soil | |
| CN114878708B (en) | Method for detecting 5 amanita peptides, dephosphorized nupharin and bufadienolide | |
| CN107144656B (en) | Method for measuring 3-acetyl-2, 5-dimethyl thiophene in edible essence by GC-MS/MS (gas chromatography-Mass Spectrometry/Mass Spectrometry) | |
| CN111929374B (en) | Liquid chromatography-mass spectrometry analysis method for carotenoid ester compounds in plants | |
| CN104931637A (en) | Method for determining PEG content in biological sample | |
| CN114740125A (en) | LC-MS-based 10 cardiovascular drug serum detection method and kit | |
| CN107515262B (en) | Liquid chromatography-mass spectrometry method for simultaneously determining lincomycin and gentamicin in animal plasma | |
| CN111751460A (en) | Method for rapidly determining benzo (a) pyrene in edible oil | |
| CN108008039B (en) | Method for measuring 3- (3, 5-di-tert-butyl-4-hydroxyphenyl) methyl propionate in plastic for food contact | |
| CN111089909B (en) | Internal standard substance, internal standard liquid, method and kit for biological sample data quality evaluation |
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 |
Application publication date: 20210129 |
|
| RJ01 | Rejection of invention patent application after publication |