Method for simultaneously detecting neotame and glycyrrhizin in tipping paper

Abstract

The invention discloses a method for simultaneously detecting neotame and glycyrrhizin in tipping paper, which comprises the following steps: (1) sample extraction: weighing the cut tipping paper, adding into an acetonitrile aqueous solution, and carrying out ultrasonic extraction for a period of time to obtain an extracting solution; (2) sample dilution: diluting the extracting solution with a mixed solution of dihydric phosphate, acetonitrile and water, and filtering to obtain a test sample; and (3) sample determination: detecting by adopting a high performance liquid chromatography to obtain the content of neotame and glycyrrhizin in the tipping paper. According to the method disclosed by the invention, the neotame and the glycyrrhizin in the tipping paper can be fully extracted at one time, the chromatographic peak is good, and the detection time is short.

Description

Technical Field

[0001] The invention belongs to the field of analytical chemistry, and particularly relates to a method for simultaneously detecting neotame and glycyrrhizin in tipping paper. Background Art

[0002] Sweeteners such as neotame, glycyrrhizin, and sucralose are commonly used additives in the food industry. Among them, ammonium glycyrrhizate, tripotassium glycyrrhizinate, and glycyrrhizic acid are all glycyrrhizin. Food additives are harmless to humans when used within the prescribed dosage range. However, excessive use can cause various forms of toxicity. Therefore, their usage must be strictly managed to maximize their beneficial effects and prevent their adverse effects. With the continuous optimization and adjustment of cigarette structure, a variety of products that add sweeteners to the tipping paper have appeared on the market to directly improve the taste and flavor of cigarettes. To achieve the regulation and sample measurement of these products, there is an urgent need to develop a simultaneous, accurate, and highly sensitive sample measurement method.

[0003] At present, the literature reports on the determination of sweeteners in foods such as dairy products [Song Ge et al., Chromatography, 2011, 29(12)], liquor [Yao Mingjing et al., Brewing Technology, 2017(10)], and beverages [Ji Chao et al., Chromatography, 2009, 27(1)]. The methods for determining sweeteners include ion chromatography, liquid chromatography, liquid chromatography-tandem mass spectrometry, gas chromatography, and gas chromatography-mass spectrometry. These methods for determining sweeteners are not suitable for the determination of sweeteners in paper matrices. Using patents CN108776187B and CN118914396A can fully extract neotame from the tipping paper, but cannot fully extract glycyrrhizin, and the chromatographic peak of glycyrrhizin cannot meet the detection requirements. Efficiently extracting neotame and glycyrrhizin from the cigarette paper and detecting their contents in the sample at the same time will help evaluate the effect of adding neotame and glycyrrhizin to the cigarette paper and promote the high-quality development of cigarette products.

[0004] To this end, the present invention establishes a liquid chromatography method that can fully extract neotame and glycyrrhizin and accurately detect them simultaneously. Summary of the Invention

[0005] The present invention provides a method for simultaneously detecting neotame and glycyrrhizin in tipping paper. The method of the present invention provides a sample extraction method, a dilution method, and a dual-wavelength detection method, thereby achieving simultaneous and accurate detection of neotame and glycyrrhizin in tipping paper.

[0006] The technical solutions of the present invention are as follows:

[0007] A method for simultaneously detecting neotame and glycyrrhizin in tipping paper comprises the following steps:

[0008] (1) Sample extraction: Weigh the shredded tipping paper, add it to an acetonitrile aqueous solution, and ultrasonically extract for a period of time to obtain an extract;

[0009] (2) Sample dilution: dilute the extract with a mixed solution of dihydrogen phosphate, acetonitrile, and water, and filter to obtain the test sample;

[0010] (3) Sample determination: High performance liquid chromatography was used to determine the content of neotame and glycyrrhizin in the tipping paper.

[0011] Preferably, in step (1), the acetonitrile aqueous solution is a 50 wt% acetonitrile aqueous solution, the mass ratio of the tipping paper to the acetonitrile aqueous solution is 1:(200-600); and the ultrasonic extraction time is 15 to 30 minutes.

[0012] Preferably, in step (2), the dihydrogen phosphate is sodium dihydrogen phosphate or sodium potassium dihydrogen phosphate; the weight ratio of the mixed solution of dihydrogen phosphate, acetonitrile and water is 0.2:50:50; the extract is diluted 5-100 times; and filtration is performed using a nylon filter membrane with a pore size of 0.22-0.45 μm.

[0013] Preferably, the liquid chromatography conditions are as follows: chromatographic column: C18 column, specifications: 3μm, 4.6mm×150mm; flow rate: 1.0mL / min; column temperature: 25-35°C; injection volume: 10μL; elution mode: gradient elution; detector: diode array detector (DAD), dual wavelength detection.

[0014] Preferably, the gradient elution conditions are: time 0-7.00 min, 30 wt% mobile phase A + 70 wt% mobile phase B; 7 min, 40 wt% mobile phase A + 60 wt% mobile phase B; 9.00 min, 95 wt% mobile phase A + 5 wt% mobile phase B.

[0015] Preferably, mobile phase A is acetonitrile, and mobile phase B is a 0.2-0.3 wt % aqueous solution of sodium dihydrogen phosphate or potassium dihydrogen phosphate.

[0016] Preferably, the dual-wavelength detection conditions are: 218 nm and 251 nm.

[0017] Preferably, high performance liquid chromatography is used for detection, and the contents of neotame and glycyrrhizin in the tipping paper are obtained according to the standard curve equations of neotame and glycyrrhizin.

[0018] Preferably, the standard curve equation of neotame is y=5183.1x+0.4311, and the standard curve equation of glycyrrhizin is y=4571.3x-0.6763.

[0019] Beneficial effects of the present invention:

[0020] 1. The method of the present invention adopts 50wt% acetonitrile aqueous solution, when the mass ratio of the tipping paper to the acetonitrile aqueous solution is 1:(200-600), ultrasonic extraction of neotame and glycyrrhizin in the tipping paper can be fully extracted in one time.

[0021] 2. The method of the present invention dilutes the extract with a mixed solution of dihydrogen phosphate, acetonitrile and water in a weight ratio of 0.2:50:50. The extract is diluted 5-100 times. The chromatographic peaks of neotame and glycyrrhizin have good peak shapes and can meet the detection requirements.

[0022] 3. The method of the present invention uses dual-wavelength detection, which is not affected by impurities and can accurately measure the content of neotame and glycyrrhizin in tipping paper. The test results are accurate and the test time is short; the test is completed in approximately 9 minutes.

[0023] 4. The extraction and detection methods of the present invention are simple, and achieve sufficient extraction and simultaneous determination of neotame and glycyrrhizin in tipping paper. This method is characterized by being simultaneous, accurate, and reproducible. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 The liquid chromatogram of the standard solution.

[0025] Figure 2 It is the liquid chromatogram of the sample solution of Example 1. DETAILED DESCRIPTION

[0026] In order to make the present invention easier to understand, the present invention will be described in detail below with reference to specific embodiments of the present invention, but this is only for illustration and not for limitation.

[0027] Example 1: Simultaneous determination of neotame and glycyrrhizin content in packaging paper A, the steps are as follows:

[0028] (1) Sample extraction: Accurately weigh 1.0000 g of shredded tipping paper, add it to 20 mL of 50% acetonitrile aqueous solution, and extract it by ultrasonication for 15 min;

[0029] (2) Sample dilution: Take 1.0 mL of the extract and dilute it to 10 mL with sodium dihydrogen phosphate-acetonitrile-water solution (weight ratio 0.2:50:50). Filter it through a 0.22 μm nylon filter membrane to obtain the test sample.

[0030] (3) Sample determination: High performance liquid chromatography was used to determine the content of neotame and glycyrrhizin in the tipping paper. The instrument conditions were as follows:

[0031] The liquid chromatography conditions are as follows: chromatographic column: C18 column, specifications: 3 μm, 4.6 mm×150 mm; flow rate: 1.0 mL / min; column temperature: 25-35° C.; injection volume: 10 μL; mobile phase A is acetonitrile, and mobile phase B is 0.2 wt% sodium dihydrogen phosphate aqueous solution; elution mode: gradient elution; detector: diode array detector (DAD), detection wavelengths are 218 nm and 251 nm; gradient elution conditions are: time 0-7.00 min, 30 wt% mobile phase A+70 wt% mobile phase B; 7 min, 40 wt% mobile phase A+60 wt% mobile phase B; 9.00 min, 95 wt% mobile phase A+5 wt% mobile phase B.

[0032] Preparation of standard solutions: Accurately weigh 5.0 mg of neotame and 10.0 mg of glycyrrhizin standard into a 10 mL volumetric flask and dissolve in 50% acetonitrile to obtain a stock solution. Based on the concentrations of the stock solutions, prepare six gradients of standard solutions ranging from 1.0 μg / mL to 500 μg / mL. Based on the concentrations and peak areas of the neotame and glycyrrhizin standard solutions, the equations for the standard curves for this experiment were y = 5183.1x + 0.4311, with a correlation coefficient R² = 0.9997; and y = 4571.3x - 0.6763, with a correlation coefficient R² = 0.9998.

[0033] Figure 1 The liquid chromatogram of the standard solution. Figure 2 It is the liquid chromatogram of the sample solution of this embodiment.

[0034] The contents of neotame and glycyrrhizin in the tipping paper A were measured to be 0.15 mg / g and 0.46 mg / g, respectively.

[0035] Example 2: Simultaneous determination of neotame and glycyrrhizin content in packaging paper B, the steps are as follows:

[0036] (1) Sample extraction: Accurately weigh 1.0000 g of shredded tipping paper, add it to 20 mL of 50% acetonitrile aqueous solution, and extract it by ultrasonication for 15 min;

[0037] (2) Sample dilution: Take 2.0 mL of the extract and dilute it to 10 mL with sodium dihydrogen phosphate-acetonitrile-water solution (weight ratio 0.2:50:50). Filter it through a 0.22 μm nylon filter membrane to obtain the test sample;

[0038] (3) Sample determination: High performance liquid chromatography was used to determine the content of neotame and glycyrrhizin in the tipping paper. The instrument conditions were the same as those in Example 1. The calibration curve equation was the same as in Example 1.

[0039] The contents of neotame and glycyrrhizin in the tipping paper B were measured to be 0.05 mg / g and 0.16 mg / g, respectively.

[0040] Example 3: Simultaneous determination of neotame and glycyrrhizin content in packaging paper C, the steps are as follows:

[0041] (1) Sample extraction: Accurately weigh 0.5000 g of shredded tipping paper, add it to 20 mL of 50% acetonitrile aqueous solution, and extract it by ultrasonication for 15 min;

[0042] (2) Sample dilution: Take 1.0 mL of the extract and dilute it to 10 mL with sodium dihydrogen phosphate-acetonitrile-water solution (weight ratio 0.2:50:50). Filter it through a 0.22 μm nylon filter membrane to obtain the test sample.

[0043] (3) Sample determination: High performance liquid chromatography was used to determine the content of neotame and glycyrrhizin in the tipping paper. The instrument conditions were the same as those in Example 1. The calibration curve equation was the same as in Example 1.

[0044] The contents of neotame and glycyrrhizin in tipping paper C were measured to be 1.77 mg / g and 7.59 mg / g, respectively.

[0045] Example 4: Simultaneous determination of neotame and glycyrrhizin content in packaging paper D, the steps are as follows:

[0046] (1) Sample extraction: Accurately weigh 0.2000 g of shredded tipping paper, add it to 20 mL of 50% acetonitrile aqueous solution, and extract it by ultrasonication for 15 min;

[0047] (2) Sample dilution: Take 1.0 mL of the extract and dilute it to 10 mL with sodium dihydrogen phosphate-acetonitrile-water solution (weight ratio 0.2:50:50). Filter it through a 0.22 μm nylon filter membrane to obtain the test sample.

[0048] (3) Sample determination: High performance liquid chromatography was used to determine the content of neotame and glycyrrhizin in the tipping paper. The instrument conditions were the same as those in Example 1. The calibration curve equation was the same as in Example 1.

[0049] The contents of neotame and glycyrrhizin in tipping paper D were measured to be 1.33 mg / g and 4.95 mg / g, respectively.

[0050] The main features and advantages of the present invention are shown and described above. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions are merely preferred examples of the present invention. Various changes and modifications may be made to the present invention without departing from the spirit and scope of the present invention. Such changes and modifications fall within the scope of the present invention as claimed.

Claims

1. A method for simultaneously detecting neotame and glycyrrhizin in tipping paper, characterized in that: The steps include: (1) Sample extraction: Weigh the shredded tipping paper, add it to an acetonitrile aqueous solution, and ultrasonically extract for a period of time to obtain an extract; (2) Sample dilution: dilute the extract with a mixed solution of dihydrogen phosphate, acetonitrile, and water, and filter to obtain the test sample; (3) Sample determination: High performance liquid chromatography was used to determine the content of neotame and glycyrrhizin in the tipping paper.

2. The method according to claim 1, characterized in that In step (1), the acetonitrile aqueous solution is a 50wt% acetonitrile aqueous solution, the mass ratio of the tipping paper to the acetonitrile aqueous solution is 1:(200-600); and the ultrasonic extraction time is 15 to 30 minutes.

3. The method according to claim 1, characterized in that In step (2), the dihydrogen phosphate is sodium dihydrogen phosphate or sodium potassium dihydrogen phosphate; the weight ratio of the mixed solution of dihydrogen phosphate, acetonitrile and water is 0.2:50:50; and the extract is diluted 5-100 times.

4. The method according to claim 1, wherein The liquid chromatography conditions were as follows: chromatographic column: C18 column, specifications: 3 μm, 4.6 mm×150 mm; flow rate: 1.0 mL / min; column temperature: 25-35°C; injection volume: 10 μL; elution method: gradient elution; detector: diode array detector, dual-wavelength detection.

5. The method according to claim 4, characterized in that The gradient elution conditions were: time 0-7.00 min, 30 wt% mobile phase A + 70 wt% mobile phase B; 7 min, 40 wt% mobile phase A + 60 wt% mobile phase B; 9.00 min, 95 wt% mobile phase A + 5 wt% mobile phase B.

6. The method according to claim 5, characterized in that Mobile phase A is acetonitrile, and mobile phase B is 0.2-0.3 wt% sodium dihydrogen phosphate or potassium dihydrogen phosphate aqueous solution.

7. The method according to claim 4, characterized in that The dual-wavelength detection conditions are: 218 nm and 251 nm.

8. The method according to claim 1, characterized in that High performance liquid chromatography was used for detection, and the contents of neotame and glycyrrhizin in the tipping paper were obtained according to the standard curve equations of neotame and glycyrrhizin.

9. The method according to claim 8, characterized in that The standard curve equation for neotame is y=5183.1x+0.4311, and the standard curve equation for glycyrrhizin is y=4571.3x-0.6763.

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