Determination of sulfur and 14 antioxidant additives in pharmaceutical rubber plugs

Abstract

The present invention discloses a method for determining sulfur and 14 antioxidant additives in a medicinal rubber plug, and relates to the technical field of material detection. The technical key points are as follows: comprising the following steps: S1, sample preparation, obtaining a test solution; S2, preparation of a standard working solution; S3, determination using a liquid chromatograph to measure the standard working solution and the test solution, using chromatography software to automatically draw a standard curve, and using an external standard method to quantitatively analyze the content of the substance to be tested in the test solution; S4, using a formula to calculate the content of the sample to be tested. The method of the present invention can simultaneously detect sulfur and 14 antioxidants in the rubber plug, greatly improving the flux problem of liquid chromatography detection of antioxidants in the rubber plug; at the same time, the method greatly reduces the high cost problem caused by the use of high performance liquid chromatography tandem mass spectrometer detection; and the present invention has great promotion value for grassroots or enterprises, and effectively reduces the relevant detection costs.

Description

Technical Field

[0001] The invention relates to the technical field of material detection, and in particular to a method for determining sulfur and 14 antioxidant additives in medicinal rubber plugs. Background Art

[0002] Rubber is widely used in the pharmaceutical industry because of its excellent performance and is processed into sealing components for pharmaceutical packaging. Rubber contains unsaturated double bonds, and environmental factors (light, heat, oxygen, etc.) will cause rubber components to age and shorten their lifespan. For this reason, synthetic antioxidants are often used as protective additives for rubber sealing components. The combination of antioxidants and rubber molecules is a physical combination. When the rubber sealing components are in use, antioxidants will migrate from them into the medicine and then be ingested by the human body. The migrated antioxidants are difficult to detect in a short period of time, and are potentially harmful to the human body. Relevant regulatory authorities and research institutions at home and abroad have formulated and promulgated regulations, standards and guidelines to strictly regulate the quality of rubber plugs. These regulations only stipulate the basic requirements for the production, use and quality control of seals, and lack restrictions on the content of antioxidants in rubber plugs, and lack detection methods for antioxidant detection.

[0003] Through searching, it is found that the current detection methods for antioxidants in rubber stoppers mainly use liquid chromatography and liquid chromatography-mass spectrometry. The existing liquid chromatography detection method can detect fewer types of detection. Although the types of antioxidants detected by liquid mass spectrometry can reach more than a dozen, the use cost and purchase cost of liquid mass spectrometry are much higher than liquid chromatography. At the same time, liquid mass spectrometry cannot detect the sulfur content in rubber stoppers.

[0004] To this end, the present invention aims to provide a method for determining sulfur and 14 antioxidant additives in pharmaceutical rubber plugs to solve the above problems. Summary of the invention

[0005] The purpose of the present invention is to solve the problem that there are few types of antioxidants to be detected in rubber stoppers in the prior art, and the use cost and purchase cost of liquid quality are much higher than those of liquid phase, and at the same time, liquid quality cannot detect the sulfur content in rubber stoppers. A method for determining sulfur and 14 antioxidant additives in medicinal rubber stoppers is provided.

[0006] In order to achieve the above object, the technical solution of the present invention is as follows:

[0007] The present invention provides a method for determining sulfur and 14 antioxidant additives in a medicinal rubber plug, comprising the following steps:

[0008] S1. Sample preparation

[0009] S1-1. Take an appropriate amount of medical rubber stoppers and cut them into particles of 2-3 mm in size; after liquid nitrogen embrittlement treatment, pour them into a high-speed grinder and grind them for about 1 minute. Continue to use liquid nitrogen embrittlement and high-speed grinder to crush them into fine and uniform particles. Dry them at 60°C for 1 hour to obtain the crushed sample;

[0010] S1-2. Take 1.0 g of the sample, weigh it accurately, put it in a 50 mL centrifuge tube, add 10 mL of n-hexane, vortex mix, ultrasonically extract for 60 min, and let it cool to room temperature; take the n-hexane extract in a 10 mL volumetric flask and dilute to the mark; take 1.0 mL of the n-hexane extract, concentrate it to near dryness under nitrogen at 40 ° C, add 1.0 mL of methanol to dissolve, and obtain the test solution;

[0011] S2. Preparation of standard working solution

[0012] Use methanol to dilute the standard stock solution step by step to prepare the standard working solution;

[0013] S3. Determination

[0014] The standard working solution and the test solution were measured by liquid chromatography, and the standard curve was automatically drawn by chromatography software. The content of the analyte in the test solution was quantitatively analyzed by the external standard method.

[0015] S4. Calculation

[0016] The content of the sample to be tested was calculated using the following formula:

[0017]

[0018] Where: X represents the content of the sample to be tested, unit: mg / kg;

[0019] c represents the measured value of the test solution, unit: μg / mL;

[0020] v represents the fixed volume, the unit is: mL;

[0021] m represents the sample mass, unit: g.

[0022] Furthermore, the preparation method of the standard stock solution described in step S2 is:

[0023] Weigh about 10 mg of TBHQ, bisphenol A, 2-tert-butylphenol, bisphenol M, antioxidant 245, antioxidant 1024, antioxidant 246, antioxidant 1135, antioxidant 3114, antioxidant 1010, antioxidant 1330, and antioxidant 1076 standard products respectively, dissolve them in acetone and make up to 10 mL, shake well, and store at 0°C to 4°C away from light;

[0024] Weigh about 10 mg of sulfur, antioxidant 300, and antioxidant 168 standard products respectively, dissolve them in dichloromethane and make up to 10 mL, shake well, and store at 0℃~4℃ away from light.

[0025] Furthermore, the working conditions of the liquid chromatograph in step S3 are:

[0026] (a) Chromatographic column: Agilent Eclipse XDB-C 8 , 4.6×250mm, 5.0μm;

[0027] (b) Wavelength: 274 nm;

[0028] (c) Flow rate: 1 mL / min;

[0029] (d) Injection volume: 10 μL;

[0030] (e) Column temperature: 35 °C;

[0031] (f) Mobile phase: methanol: water (containing 0.1% formic acid) gradient elution.

[0032] Compared with the prior art, this solution has the following beneficial effects:

[0033] 1. In the scheme of the present invention, by optimizing the combination of chromatographic conditions, extraction methods, etc., sulfur and 14 antioxidants in rubber plugs can be detected simultaneously, which greatly improves the flux problem of liquid chromatography detection of antioxidants in rubber plugs;

[0034] 2. The method of the present invention greatly reduces the high cost problem caused by the use of high performance liquid chromatography tandem mass spectrometer detection; moreover, the method has great promotion value for grassroots or enterprises, and effectively reduces the relevant detection costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 is a chromatogram in an embodiment of the present invention;

[0036] Figure 2 is a TBHQ-linear diagram in an embodiment of the present invention;

[0037] Figure 3 is a bisphenol A-linear diagram in an embodiment of the present invention;

[0038] Figure 4 It is the 2-tert-butylphenol-linear diagram in the embodiment of the present invention;

[0039] Figure 5 is a bisphenol M-linear diagram in an embodiment of the present invention;

[0040] Figure 6 is the antioxidant 245-linear diagram in the embodiment of the present invention;

[0041] Figure 7 is an antioxidant 300-linear graph in an embodiment of the present invention;

[0042] Figure 8 is an antioxidant 1024-linear diagram in an embodiment of the present invention;

[0043] Fig. 9 is the antioxidant 246-linear diagram in the embodiment of the present invention;

[0044] Fig.10 is a sulfur-linear diagram in an embodiment of the present invention;

[0045] Fig.11 is the antioxidant 1135-linear diagram in the embodiment of the present invention;

[0046] Fig.12 It is the antioxidant 3114-linear diagram in the embodiment of the present invention;

[0047] Fig.13 is a linear graph of antioxidant 1010 in an embodiment of the present invention;

[0048] Fig.14 It is the antioxidant 1330-linear diagram in the embodiment of the present invention;

[0049] Fig.15 It is the antioxidant 1076-linear diagram in the embodiment of the present invention;

[0050] Fig.16 It is a linear graph of antioxidant 168 in the embodiment of the present invention. DETAILED DESCRIPTION

[0051] In order to enable those skilled in the art to better understand the solution of the present invention, the technical solution of the present invention will be further described in detail below in conjunction with the embodiments of the present invention and the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0052] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present invention can be combined with each other. The present invention will be described in detail below in conjunction with the embodiments.

[0053] Example:

[0054] The solution provided by the embodiment of the present invention is as described in the above invention content, and provides a method for determining sulfur and 14 antioxidant additives in a medicinal rubber plug, which is used for detecting sulfur and antioxidant additives in rubber products, such as for detecting sulfur and 14 antioxidant additives in a medicinal rubber plug. The specific implementation process of the determination method is as follows:

[0055] 1. Scope

[0056] The operating process of the determination method of the present invention is suitable for the determination of sulfur, TBHQ, bisphenol A, 2-tert-butylphenol, bisphenol M, antioxidant 245, antioxidant 300, antioxidant 1024, antioxidant 246, antioxidant 1135, antioxidant 3114, antioxidant 1010, antioxidant 1330, antioxidant 1076, and antioxidant 168 in medicinal rubber stoppers.

[0057] 2. Principle

[0058] The medicinal rubber stopper was crushed, extracted with n-hexane, detected by liquid chromatography, and quantified by external standard method.

[0059] 3. Reagents

[0060] 3.1 Methanol: chromatographic grade;

[0061] 3.2 n-Hexane: chromatographic grade;

[0062] 3.3 Acetone: chromatographic grade;

[0063] 3.4 Dichloromethane: chromatographically pure;

[0064] 3.5 Liquid nitrogen: stored in liquid nitrogen tank;

[0065] 3.6 Sulfur, TBHQ, bisphenol A, 2-tert-butylphenol, bisphenol M, antioxidant 245, antioxidant 300, antioxidant 1024, antioxidant 246, antioxidant 1135, antioxidant 3114, antioxidant 1010, antioxidant 1330, antioxidant 1076, antioxidant 168 standard products: purity ≥ 95%;

[0066] 3.7 Standard stock solution: Weigh about 10 mg of TBHQ, bisphenol A, 2-tert-butylphenol, bisphenol M, antioxidant 245, antioxidant 1024, antioxidant 246, antioxidant 1135, antioxidant 3114, antioxidant 1010, antioxidant 1330, antioxidant 1076 standard products, dissolve them in acetone and dilute to 10 mL, shake well, and store at 0℃~4℃ away from light. Weigh about 10 mg of sulfur, antioxidant 300, and antioxidant 168 standard products, dissolve them in dichloromethane and dilute to 10 mL, shake well, and store at 0℃~4℃ away from light.

[0067] 4. Instruments and equipment

[0068] 4.1 Thermo Fisher Ultimate 3000 liquid chromatograph, equipped with a diode array detector (DAD). The working conditions of the liquid chromatograph are:

[0069] (a) Chromatographic column: Agilent Eclipse XDB-C 8 , 4.6×250mm, 5.0μm;

[0070] (b) Wavelength: 274 nm;

[0071] (c) Flow rate: 1 mL / min;

[0072] (d) Injection volume: 10 μL;

[0073] (e) Column temperature: 35 °C;

[0074] (f) Mobile phase: methanol: water solution containing 0.1% formic acid gradient elution. The elution program is shown in Table 1 below;

[0075] Table 1 Liquid chromatography gradient elution program

[0076]

[0077]

[0078] 42,000ths of a scale;

[0079] 4.3 one hundred thousandth of a balance;

[0080] 4.4 High-speed crusher;

[0081] 4.5 Ultrasonic cleaning machine;

[0082] 4.6 Vortex mixer;

[0083] 4.7 Nitrogen blowing apparatus;

[0084] 5. Analysis steps

[0085] 5.1 Sample preparation

[0086] Take an appropriate amount of medical rubber stopper and cut it into particles of 2-3 mm in size. After liquid nitrogen embrittlement treatment, pour it into a high-speed grinder and crush it for about 1 minute. Continue to use liquid nitrogen embrittlement, and crush it into fine and uniform particles by a high-speed grinder. Dry it at 60℃ for 1h to obtain the crushed sample. Take 1.0g of the sample, accurately weigh it, put it in a 50mL centrifuge tube, add 10mL of n-hexane, vortex mix, ultrasonically extract for 60min, and let it cool to room temperature. Take the n-hexane extract in a 10mL volumetric flask and dilute to the scale. Take 1.0mL of the n-hexane extract, concentrate it to near dryness with nitrogen at 40℃, add 1.0mL of methanol to dissolve it, and obtain the test solution.

[0087] 5.2 Preparation of standard working solution

[0088] The standard stock solution (prepared in 3.7 above) was diluted stepwise with methanol to prepare the standard working solution. The linear range and correlation coefficient are shown in Table 2 below.

[0089] Table 2 Linear range, linear equation and correlation coefficient of sulfur and 14 antioxidants in pharmaceutical rubber plugs

[0090]

[0091] 5.3 Determination

[0092] The standard working solution and the test solution were measured by liquid chromatography, the standard curve was automatically drawn by chromatography software, and the content of the analyte in the test solution was quantitatively analyzed by the external standard method.

[0093] 6. Calculation

[0094]

[0095] Where:

[0096] X represents the content of the sample to be tested, the unit is: mg / kg;

[0097] c represents the measured value of the test solution, unit: μg / mL;

[0098] v represents the fixed volume, the unit is: mL;

[0099] m represents the sample mass, unit: g.

[0100] 7. Quality Control

[0101] 7.1 Linear range and correlation coefficient

[0102] The linear ranges of sulfur, TBHQ, bisphenol A, 2-tert-butylphenol, bisphenol M, antioxidant 245, antioxidant 300, antioxidant 1024, antioxidant 246, antioxidant 1135, antioxidant 3114, antioxidant 1010, antioxidant 1330, antioxidant 1076, and antioxidant 168 in the method of the present invention are shown in Table 2.

[0103] 7.2 Limit of detection and limit of quantification

[0104] According to the response value of the standard solution, the standard solution was diluted step by step, and the detection limit was set at a standard solution concentration with a signal-to-noise ratio of approximately 3, and the quantification limit was set at a standard solution concentration with a signal-to-noise ratio of approximately 10. The detection limit and quantification limit of this method are shown in Table 2.

[0105] Through the above embodiments of the present invention, compared with the prior art, the determination method of the present invention can simultaneously detect sulfur and 14 antioxidants in the rubber plug by optimizing the combination of chromatographic conditions, extraction methods, etc., which greatly improves the flux problem of liquid chromatography detection of antioxidants in rubber plugs; at the same time, the method greatly reduces the high cost problem caused by the use of high performance liquid chromatography tandem mass spectrometer detection; and it has great promotion value for grassroots or enterprises, and effectively reduces the relevant detection costs.

[0106] The above specific embodiments are merely explanations of the present invention and are not limitations of the present invention. After reading this specification, those skilled in the art may make modifications to the embodiments without any creative contribution as needed. However, such modifications are protected by the patent law as long as they are within the scope of the claims of the present invention.

Claims

1. Determination of sulfur and 14 antioxidant additives in pharmaceutical rubber plugs. Its characteristics are: The following steps are involved: S1. Sample preparation S1-1. Take an appropriate amount of medical rubber stoppers and cut them into particles of 2-3 mm in size; after liquid nitrogen embrittlement treatment, pour them into a high-speed grinder and grind them for about 1 minute. Continue to use liquid nitrogen embrittlement and high-speed grinder to crush them into fine and uniform particles. Dry them at 60°C for 1 hour to obtain the crushed sample; S1-2. Take 1.0 g of the sample, weigh it accurately, put it in a 50 mL centrifuge tube, add 10 mL of n-hexane, vortex mix, ultrasonically extract for 60 min, and let it cool to room temperature; take the n-hexane extract in a 10 mL volumetric flask and dilute to the mark; take 1.0 mL of the n-hexane extract, concentrate it to near dryness under nitrogen at 40 ° C, add 1.0 mL of methanol to dissolve, and obtain the test solution; S2. Preparation of standard working solution Use methanol to dilute the standard stock solution step by step to prepare the standard working solution; S3. Determination The standard working solution and the test solution were measured by liquid chromatography, and the standard curve was automatically drawn by chromatography software. The content of the analyte in the test solution was quantitatively analyzed by the external standard method. S4. Calculation The content of the sample to be tested was calculated using the following formula: Where: X represents the content of the sample to be tested, unit: mg / kg; c represents the measured value of the test solution, unit: μg / mL; v represents the fixed volume, the unit is: mL; m represents the sample mass, unit: g; The preparation method of the standard stock solution described in step S2 is: Weigh about 10 mg of TBHQ, bisphenol A, 2-tert-butylphenol, bisphenol M, antioxidant 245, antioxidant 1024, antioxidant 246, antioxidant 1135, antioxidant 3114, antioxidant 1010, antioxidant 1330, and antioxidant 1076 standard products respectively, dissolve them in acetone and make up to 10 mL, shake well, and store at 0°C to 4°C away from light; Weigh about 10 mg of sulfur, antioxidant 300, and antioxidant 168 standard products respectively, dissolve them in dichloromethane and make up to 10 mL, shake well, and store at 0℃~4℃ away from light; The operating conditions of the liquid chromatograph in step S3 are: (a) Chromatographic column: Agilent Eclipse XDB-C8, 4.6×250 mm, 5.0 μm; (b) Wavelength: 274 nm; (c) Flow rate: 1 mL / min; (d) Injection volume: 10 μL; (e) Column temperature: 35 °C; (f) Mobile phase: Gradient elution with methanol: water solution containing 0.1% formic acid. The specific elution process is as follows;

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