Method for determining contents of cetirizine hydrochloride and preservatives in cetirizine hydrochloride oral solution

Abstract

The invention relates to the field of pharmaceutical analysis, in particular to a method for determining the content of cetirizine hydrochloride and various preservatives in a cetirizine hydrochloride oral solution. According to the detection method provided by the invention, octadecyl bonded silica gel is used as a filler of a chromatographic column, a mixed solution with specific composition and proportion is used as a mobile phase, isocratic elution is adopted, a test solution is prepared by using an internal volume transfer pipette, and the test solution and a reference substance mixed solution are respectively injected into a liquid chromatograph for liquid chromatography testing. Respectively obtaining a chromatogram of the test solution and a chromatogram of the reference substance mixed solution; and calculating by peak areas according to an external standard method so as to respectively obtain the content of cetirizine hydrochloride, the content of a methylparaben preservative and the content of a propyl hydroxybenzoate preservative in the cetirizine hydrochloride oral solution. The method provided by the invention has the advantages of strong specificity, high accuracy, good precision, linear relationship and stability, and is beneficial to evaluation of sample quality.

Description

Technical Field

[0001] The present invention relates to the field of pharmaceutical analysis, and particularly to a method for determining the content of cetirizine hydrochloride and various preservatives in cetirizine hydrochloride oral solution. Background Art

[0002] Cetirizine hydrochloride oral solution is an antihistamine drug, mainly used to relieve seasonal rhinitis, perennial allergic rhinitis, allergic conjunctivitis, and itching and urticaria caused by allergy.

[0003] In the production process of cetirizine hydrochloride oral solution, in addition to the active ingredient, various excipients are added, including glycerol, propylene glycol, amorphous sorbitol solution, saccharin sodium, essence, glacial acetic acid, sodium acetate, and preservatives methylparaben and propylparaben. To ensure the quality of the oral solution, it is necessary to exclude the interference of various excipients, and at the same time accurately and effectively separate the two preservatives and the active ingredient cetirizine hydrochloride. Moreover, the antibacterial effect of the preservatives in long-term stability makes it crucial to effectively monitor the content of the preservatives. Therefore, the accurate quantitative determination of cetirizine hydrochloride and the two preservatives in cetirizine hydrochloride oral solution is particularly important for production and quality control. Summary of the Invention

[0004] In view of this, the present invention provides a method for determining the content of cetirizine hydrochloride and various preservatives in cetirizine hydrochloride oral solution. The test method provided by the present invention can effectively measure the content of the active ingredient cetirizine hydrochloride and the two preservatives (methylparaben, propylparaben) in cetirizine hydrochloride oral solution, which is beneficial to the quality control in the production of cetirizine hydrochloride oral solution.

[0005] The present invention provides a method for determining the content of cetirizine hydrochloride and various preservatives in cetirizine hydrochloride oral solution, including the following steps:

[0006] A) Preparation of test solution:

[0007] Precisely measure 5 mL of this product with a volumetric pipette, place it in a 100 mL volumetric flask, dilute it to the scale with the mobile phase, and shake well to obtain the test solution;

[0008] B) Preparation of reference mixture solution:

[0009] Preparation of cetirizine hydrochloride reference stock solution: Take 20 mg of cetirizine hydrochloride reference substance, accurately weigh it, place it in a 20 mL volumetric flask, dissolve it with the mobile phase and dilute it to the scale, and shake well to obtain it;

[0010] Preparation of methylparaben reference stock solution: Take 27 mg of methylparaben reference substance, accurately weigh it, place it in a 20 mL volumetric flask, dissolve it with the mobile phase and dilute it to the scale, and shake well to obtain it;

[0011] Preparation of propylparaben reference stock solution: Take 30 mg of propylparaben reference substance, accurately weigh it, place it in a 20 mL volumetric flask, dissolve it with the mobile phase and dilute it to the scale, shake well to obtain the initial solution; then accurately measure 2 mL of the initial solution, place it in a 20 mL volumetric flask, dissolve it with the mobile phase and dilute it to the scale, shake well to obtain it;

[0012] Accurately measure 5 mL each of the cetirizine hydrochloride reference stock solution, methylparaben reference stock solution and propylparaben reference stock solution, place them in a 100 mL volumetric flask, dilute them to the scale with the mobile phase, shake well to obtain a mixed reference solution;

[0013] C) Liquid chromatography test:

[0014] Accurately measure the test solution and the mixed reference solution, inject them into the liquid chromatograph respectively for liquid chromatography test, and obtain the chromatogram of the test solution and the chromatogram of the mixed reference solution respectively; then according to the external standard method, obtain the content of cetirizine hydrochloride, the content of methylparaben preservative and the content of propylparaben preservative in the cetirizine hydrochloride oral solution respectively;

[0015] Among them, the conditions of the liquid chromatography test are as follows:

[0016] Chromatographic column: Octadecylsilane chemically bonded silica packing material;

[0017] Mobile phase: Adjust the pH of a 0.1 mol / L potassium dihydrogen phosphate solution to 3.7 with phosphoric acid, and then mix it with acetonitrile in a volume ratio of 65:35 to obtain the mobile phase;

[0018] Mobile phase flow rate: 0.8 - 1.2 mL / min;

[0019] Chromatographic column temperature: 25 - 35 °C;

[0020] Detection wavelength: 232 nm;

[0021] Injection volume: 20 μL;

[0022] Elution mode: Isocratic elution;

[0023] Among them, there is no order limit for steps A) and B).

[0024] Preferably, in step A), the concentration of the test solution is: 50 μg of cetirizine hydrochloride per 1 mL of the test solution.

[0025] Preferably, in step B), the concentration of the mixed reference solution is: 50 μg of cetirizine hydrochloride, 67.5 μg of methylparaben and 7.5 μg of propylparaben per 1 mL of the mixed reference solution.

[0026] Preferably, in step C), the external standard method is calculated by the following formulas (1) to (2):

[0027]

[0028] In formula (1):

[0029] F: correction factor;

[0030] m s : Sampling amount of each reference substance of cetirizine hydrochloride, methylparaben or propylparaben, mg;

[0031] p: Purity of each reference substance of cetirizine hydrochloride, methylparaben or propylparaben;

[0032] V s : Dilution volume of each reference substance to the reference substance mixed solution, mL;

[0033] A s : Peak area of cetirizine hydrochloride, methylparaben or propylparaben in the reference substance mixed solution;

[0034]

[0035] In formula (2):

[0036] W: Content of cetirizine hydrochloride, methylparaben or propylparaben in cetirizine hydrochloride oral solution, %;

[0037] F: Correction factor calculated by formula (1);

[0038] A R : Peak area of cetirizine hydrochloride, methylparaben or propylparaben in the test solution;

[0039] V R : Dilution volume of the test solution, mL;

[0040] V: Volume of the cetirizine hydrochloride oral solution sample taken in the test solution, mL;

[0041] C: Labeled amount of cetirizine hydrochloride, methylparaben or propylparaben in the cetirizine hydrochloride oral solution sample, mg / mL.

[0042] Preferably, in formula (2), the parameter C is as follows:

[0043] The labeled amount of cetirizine hydrochloride in the cetirizine hydrochloride oral solution sample is 1 mg / mL, the labeled amount of methylparaben is 1.35 mg / mL, and the labeled amount of propylparaben is 0.15 mg / mL.

[0044] Preferably, the chromatographic column is one of Agilent SB / XDB / EXTEND C18, Welch Xtimate, and MORHCHEM Caprisil C18-P.

[0045] Preferably, the specifications of the chromatographic column are: length 250 mm, inner diameter 4.6 mm, and packing material particle size 5 μm.

[0046] Preferably, the flow rate of the mobile phase is 1.0 mL / min.

[0047] Preferably, the temperature of the chromatographic column is 30 °C.

[0048] Preferably, in step C), the liquid chromatography test is a high performance liquid chromatography test.

[0049] For the detection method provided by the present invention, an octadecylsilane bonded silica gel is used as the packing material for the chromatographic column, a mixed solution with a specific composition and ratio is used as the mobile phase, isocratic elution is adopted, a test solution is prepared with a volumetric pipette, the test solution and the reference solution are respectively injected into a liquid chromatograph for liquid chromatography testing, so as to obtain the chromatogram of the test solution and the chromatogram of the reference solution respectively; then, calculation is performed based on the external standard method using the peak area, so as to obtain the contents of cetirizine hydrochloride, methylparaben preservative, and propylparaben preservative in the cetirizine hydrochloride oral solution respectively. The method of the present invention can quantitatively determine the contents of cetirizine hydrochloride and various preservatives in the cetirizine hydrochloride oral solution, so as to ensure the quality controllability of the cetirizine hydrochloride oral solution. The method of the present invention has strong specificity, high accuracy, and good precision, linear relationship, and stability, and can accurately detect the contents of cetirizine hydrochloride and two preservatives in the cetirizine hydrochloride oral solution, which is beneficial to evaluating the sample quality; in addition, the method of the present invention is simple to operate and easy to implement. Description of the Drawings

[0050] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following drawings are only the embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on the provided drawings.

[0051] Figure 1 It is the chromatogram of the blank solvent in the specificity verification of Example 1;

[0052] Figure 2 It is the chromatogram of the blank excipient solution 1 (without cetirizine hydrochloride) in the specificity verification of Example 1;

[0053] Figure 3Chromatogram of blank excipient solution 2 (without preservatives methylparaben and propylparaben) in the specificity verification of Example 1;

[0054] Figure 4 Chromatogram of reference solution in the specificity verification of Example 1;

[0055] Figure 5 Chromatogram of test solution in the specificity verification of Example 1;

[0056] Figure 6 Linear graph of cetirizine hydrochloride;

[0057] Figure 7 Linear graph of methylparaben;

[0058] Figure 8 Linear graph of propylparaben;

[0059] Figure 9 Chromatogram at a mobile phase ratio of 60:40 under the chromatographic column MORHCHEM Caprisil;

[0060] Figure 10 Chromatogram at a mobile phase ratio of 65:35 under the chromatographic column MORHCHEM Caprisil;

[0061] Figure 11 Chromatogram at a mobile phase ratio of 60:40 under the chromatographic column Agilent, SB / XDB / EXTEND;

[0062] Figure 12 Chromatogram at a mobile phase ratio of 65:35 under the chromatographic column Agilent, SB / XDB / EXTEND;

[0063] Figure 13 Chromatogram at a mobile phase ratio of 60:40 under the chromatographic column Welch, Xtimate;

[0064] Figure 14 Chromatogram at a mobile phase ratio of 65:35 under the chromatographic column Welch, Xtimate. Detailed implementation manners

[0065] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which this application belongs. The terms used in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0066] In this article, among the technical features described in an open-ended manner, there are included closed technical solutions composed of the listed features, as well as open technical solutions containing the listed features.

[0067] As used herein, the term "and / or" includes any and all combinations of one or more of the related listed items.

[0068] In this article, when it comes to numerical ranges, unless otherwise specified, the above numerical ranges are considered continuous and include the minimum and maximum values of the range, as well as each value between such minimum and maximum values. Further, when the range refers to integers, it includes each integer between the minimum and maximum values of the range. In addition, when multiple ranges are provided to describe features or characteristics, the ranges can be combined. In other words, unless otherwise specified, all ranges disclosed herein should be understood to include any and all sub-ranges subsumed therein.

[0069] In this article, regarding the units of data ranges, if there is only a unit after the right endpoint, it means that the units of the left endpoint and the right endpoint are the same. For example, 0.8~1.2 mL / min means that the units of the left endpoint "0.8" and the right endpoint "1.2" are both mL / min.

[0070] The present invention provides a method for determining the content of cetirizine hydrochloride and each preservative in cetirizine hydrochloride oral solution, comprising the following steps:

[0071] A) Preparing a test solution:

[0072] Precisely pipette 5 mL of this product with a volumetric pipette with a specified content volume, place it in a 100 mL volumetric flask, dilute it to the mark with the mobile phase, and shake well to obtain a test solution;

[0073] B) Preparing a reference mixture solution:

[0074] Preparing a stock solution of cetirizine hydrochloride reference substance: Take 20 mg of cetirizine hydrochloride reference substance, accurately weigh it, place it in a 20 mL volumetric flask, dissolve it with the mobile phase and dilute it to the mark, and shake well to obtain it;

[0075] Preparing a stock solution of methylparaben reference substance: Take 27 mg of methylparaben reference substance, accurately weigh it, place it in a 20 mL volumetric flask, dissolve it with the mobile phase and dilute it to the mark, and shake well to obtain it;

[0076] Preparing a stock solution of propylparaben reference substance: Take 30 mg of propylparaben reference substance, accurately weigh it, place it in a 20 mL volumetric flask, dissolve it with the mobile phase and dilute it to the mark, and shake well to obtain an initial solution; then precisely pipette 2 mL of the said initial solution, place it in a 20 mL volumetric flask, dissolve it with the mobile phase and dilute it to the mark, and shake well to obtain it;

[0077] Precisely measure 5 mL each of the cetirizine hydrochloride reference stock solution, methylparaben reference stock solution, and propylparaben reference stock solution, transfer them into a 100 mL volumetric flask, dilute to the mark with the mobile phase, and mix well to obtain a mixed reference solution;

[0078] C) Liquid chromatography test:

[0079] Precisely measure the test solution and the mixed reference solution, and inject them into the liquid chromatograph for liquid chromatography test respectively to obtain the chromatogram of the test solution and the chromatogram of the mixed reference solution; then according to the external standard method, obtain the content of cetirizine hydrochloride, the content of methylparaben preservative, and the content of propylparaben preservative in the cetirizine hydrochloride oral solution respectively;

[0080] Among them, the conditions for the liquid chromatography test are as follows:

[0081] Chromatographic column: Octadecylsilane chemically bonded silica packing material;

[0082] Mobile phase: Adjust the pH of a 0.1 mol / L potassium dihydrogen phosphate solution to 3.7 with phosphoric acid, and then mix it with acetonitrile in a volume ratio of 65:35 to obtain the mobile phase;

[0083] Mobile phase flow rate: 0.8 - 1.2 mL / min;

[0084] Chromatographic column temperature: 25 - 35 °C;

[0085] Detection wavelength: 232 nm;

[0086] Injection volume: 20 μL;

[0087] Elution mode: Isocratic elution;

[0088] Among them, there is no order limit for steps A) and B).

[0089] [Regarding step A]:

[0090] A) Preparation of the test solution: Precisely measure 5 mL of this product with a volumetric pipette with internal capacity, transfer it into a 100 mL volumetric flask, dilute to the mark with the mobile phase, and mix well to obtain the test solution.

[0091] In the present invention, the "this product" refers to the cetirizine hydrochloride oral solution. The cetirizine hydrochloride oral solution has a certain viscosity. When using an ordinary pipette to transfer the test sample, the prepared test solution is likely to adhere to the inner wall of the pipette, resulting in certain errors. In the present invention, a volumetric pipette with internal capacity is used to prepare the test solution, which can reduce the errors in the preparation of the test solution.

[0092] In the present invention, the mobile phase is the same as that in the subsequent liquid chromatography test. The mobile phase is prepared by the following method: adjusting the pH of a 0.1 mol / L potassium dihydrogen phosphate solution to 3.7 with phosphoric acid, and then mixing it with acetonitrile in a volume ratio of 65:35 to obtain the mobile phase. Among them, the potassium dihydrogen phosphate solution is an aqueous solution of potassium dihydrogen phosphate. Adjust the pH of the potassium dihydrogen phosphate solution to 3.7 with phosphoric acid, and then mix it with acetonitrile in a volume ratio of 65:35 to obtain the mobile phase.

[0093] In the present invention, the oral solution of cetirizine hydrochloride is diluted with the mobile phase to obtain a test solution. Specifically, accurately measure 5 mL of this product with a volumetric pipette, place it in a 100 mL volumetric flask, dilute it to the mark with the mobile phase, and shake well to obtain the test solution.

[0094] In the present invention, preferably, the concentration of the test solution is: 50 μg of cetirizine hydrochloride is contained in each 1 mL of the test solution. That is, accurately measure this product with a volumetric pipette and dilute it with the mobile phase to prepare a solution containing 50 μg of cetirizine hydrochloride in each 1 mL, and then the test solution is obtained.

[0095] [Regarding step B]:

[0096] B) Prepare a reference substance mixed solution:

[0097] Prepare a stock solution of cetirizine hydrochloride reference substance: Take 20 mg of cetirizine hydrochloride reference substance, accurately weigh it, place it in a 20 mL volumetric flask, dissolve it with the mobile phase and dilute it to the mark, and shake well to obtain it;

[0098] Prepare a stock solution of methylparaben reference substance: Take 27 mg of methylparaben reference substance, accurately weigh it, place it in a 20 mL volumetric flask, dissolve it with the mobile phase and dilute it to the mark, and shake well to obtain it;

[0099] Prepare a stock solution of propylparaben reference substance: Take 30 mg of propylparaben reference substance, accurately weigh it, place it in a 20 mL volumetric flask, dissolve it with the mobile phase and dilute it to the mark, and shake well to obtain the initial solution; then accurately measure 2 mL of the initial solution, place it in a 20 mL volumetric flask, dissolve it with the mobile phase and dilute it to the mark, and shake well to obtain it;

[0100] Accurately measure 5 mL each of the stock solution of cetirizine hydrochloride reference substance, the stock solution of methylparaben reference substance, and the stock solution of propylparaben reference substance, place them in a 100 mL volumetric flask, dilute it to the mark with the mobile phase, and shake well to obtain the reference substance mixed solution.

[0101] In the present invention, cetirizine hydrochloride, methylparaben, and propylparaben are used as reference substances respectively. There are no special restrictions on the sources of the above reference substances, and commercially available products can be used.

[0102] There is no special limitation on the order of preparing the stock solutions of cetirizine hydrochloride reference substance, methylparaben reference substance, and propylparaben reference substance.

[0103] In the present invention, the mobile phase is the mobile phase in the subsequent liquid chromatography test. The mobile phase is prepared by the following method: adjusting the pH of a 0.1 mol / L potassium dihydrogen phosphate solution to 3.7 with phosphoric acid, and then mixing it with acetonitrile in a volume ratio of 65:35 to obtain the mobile phase. Among them, the potassium dihydrogen phosphate solution is an aqueous solution of potassium dihydrogen phosphate. Adjust the pH of the potassium dihydrogen phosphate solution to 3.7 with phosphoric acid, and then mix it with acetonitrile in a volume ratio of 65:35 to obtain the mobile phase.

[0104] In the present invention, the reference substances of cetirizine hydrochloride, methylparaben, and propylparaben are accurately weighed respectively, and then dissolved in the mobile phase and diluted with the mobile phase to prepare the stock solutions of each reference substance. Then, a certain volume (5 mL) of each stock solution of the reference substance is measured respectively, placed in a 100 mL volumetric flask, and diluted with the mobile phase to the specific scale and shaken well to obtain the reference substance mixed solution.

[0105] In the present invention, the concentration of the reference substance mixed solution is: each 1 mL of the reference substance mixed solution contains 50 μg of cetirizine hydrochloride, 67.5 μg of methylparaben, and 7.5 μg of propylparaben.

[0106] The present invention has no order limitation on step A) and step B).

[0107] [Regarding step C]:

[0108] C) Liquid chromatography test: Accurately measure the test solution and the reference substance mixed solution, and inject them into the liquid chromatograph respectively for liquid chromatography test to obtain the chromatogram of the test solution and the chromatogram of the reference substance mixed solution respectively; then according to the external standard method, obtain the content of cetirizine hydrochloride, the content of methylparaben preservative, and the content of propylparaben preservative in the cetirizine hydrochloride oral solution respectively.

[0109] In the present invention, the liquid chromatography test is preferably a high performance liquid chromatography test, i.e., HPLC test.

[0110] In the present invention, the conditions of the liquid chromatography test are as follows:

[0111] Chromatographic column: Octadecylsilyl silica gel packing material;

[0112] Mobile phase: Adjust the pH of a 0.1 mol / L potassium dihydrogen phosphate solution to 3.7 with phosphoric acid, and then mix it with acetonitrile in a volume ratio of 65:35 to obtain the mobile phase;

[0113] Mobile phase flow rate: 0.8 - 1.2 mL / min;

[0114] Column temperature: 25 - 35 °C;

[0115] Detection wavelength: 232 nm;

[0116] Injection volume: 20 μL;

[0117] Elution mode: isocratic elution.

[0118] Wherein:

[0119] The chromatographic column is preferably one of Agilent SB / XDB / EXTEND C18, Welch Xtimate, and MORHCHEM Caprisil C18-P. The specifications of the chromatographic column are preferably: length 250 mm, inner diameter 4.6 mm, and packing material particle size 5 μm.

[0120] The mobile phase is prepared by the following method: adjust the pH of a 0.1 mol / L potassium dihydrogen phosphate solution to 3.7 with phosphoric acid, and then mix it with acetonitrile at a volume ratio of 65:35 to obtain the mobile phase. Liquid chromatography is to separate sample components by exchanging between the column packing and the mobile phase. Therefore, it is required that the mobile phase has a certain solubility for the sample, does not react chemically with the sample, and is compatible with the detector. The specific mobile phase used in the present invention can achieve better detection results, superior to other mobile phases. The flow rate of the mobile phase can specifically be 0.8 mL / min, 0.9 mL / min, 1.0 mL / min, 1.1 mL / min, 1.2 mL / min, and more preferably 1.0 mL / min.

[0121] The temperature of the chromatographic column can specifically be 25 °C, 26 °C, 27 °C, 28 °C, 29 °C, 30 °C, 31 °C, 32 °C, 33 °C, 34 °C, 35 °C, and more preferably 30 °C.

[0122] Inject the test solution and the reference solution into the liquid chromatograph for liquid chromatography testing respectively, so as to obtain the chromatogram of the test solution and the chromatogram of the reference solution respectively; then calculate according to the external standard method with the peak area to obtain the content of cetirizine hydrochloride, the content of methylparaben preservative, and the content of propylparaben preservative in the cetirizine hydrochloride oral solution respectively.

[0123] In the present invention, the external standard method is calculated by the following formulas (1) - (2):

[0124]

[0125] In formula (1):

[0126] F: correction factor;

[0127] m s : Sampling quantity of each reference substance of cetirizine hydrochloride, methylparaben or propylparaben, mg;

[0128] p: Purity of each reference substance of cetirizine hydrochloride, methylparaben or propylparaben;

[0129] V s : Dilution volume of each reference substance to the reference substance mixed solution, mL;

[0130] A s : Peak area of cetirizine hydrochloride, methylparaben or propylparaben in the reference substance mixed solution;

[0131]

[0132] In formula (2):

[0133] W: Content of cetirizine hydrochloride, methylparaben or propylparaben in the cetirizine hydrochloride oral solution, %;

[0134] F: Correction factor calculated by formula (1);

[0135] A R : Peak area of cetirizine hydrochloride, methylparaben or propylparaben in the test solution;

[0136] V R : Dilution volume of the test solution, mL;

[0137] V: Volume of the cetirizine hydrochloride oral solution taken in the test solution, mL;

[0138] C: Labeled amount of cetirizine hydrochloride, methylparaben or propylparaben in the cetirizine hydrochloride oral solution, mg / mL.

[0139] In the above formula (1), the dilution volume V of each reference substance to the reference substance mixed solution s , refers to the dilution volume (or dilution multiple) from the reference substance stock solution to the preparation of the reference substance mixed solution. The dilution volume of methylparaben is 20×100 / 5 = 400, the dilution volume of propylparaben is 20×20×100 / 2 / 5 = 4000, and the dilution volume of cetirizine hydrochloride is 20×100 / 5 = 400. In formula (2), the dilution volume V of the test solution R / V, refers to the dilution volume (or dilution multiple) from the cetirizine hydrochloride oral solution to the preparation of the test solution, specifically 100 / 5 = 20.

[0140] Quantitative detection of substances using high performance liquid chromatography (HPLC) is a well-known detection method. However, the prior art has not reported how to quantitatively detect the active ingredient of cetirizine hydrochloride and two preservatives (methylparaben, propylparaben) in cetirizine hydrochloride oral solution. If HPLC is to be used to detect a new substance, it is necessary to reasonably design the test procedures and process conditions to meet the requirements in terms of accuracy, specificity, system suitability, linearity, precision, durability, etc.

[0141] For the detection method provided by the present invention, the chromatographic column is packed with octadecylsilane bonded silica gel, a mixed solution with a specific composition and ratio is used as the mobile phase, isocratic elution is adopted, the test solution is prepared with an internal capacity pipette, and the test solution and the reference solution mixed solution are respectively injected into the liquid chromatograph for liquid chromatography testing, so as to obtain the chromatogram of the test solution and the chromatogram of the reference solution mixed solution respectively; then, according to the external standard method, the peak area is calculated to obtain the content of cetirizine hydrochloride, the content of methylparaben preservative and the content of propylparaben preservative in the cetirizine hydrochloride oral solution respectively. The method of the present invention can quantitatively determine the content of cetirizine hydrochloride and various preservatives in the cetirizine hydrochloride oral solution, so as to ensure the quality control of the cetirizine hydrochloride oral solution. The method of the present invention has strong specificity and high accuracy, and has good precision, linear relationship and stability, and can accurately detect the content of cetirizine hydrochloride and two preservatives in the cetirizine hydrochloride oral solution, which is beneficial to evaluating the sample quality; in addition, the method of the present invention is simple to operate and easy to implement.

[0142] To further understand the present invention, the preferred embodiments of the present invention will be described below in conjunction with examples. However, it should be understood that these descriptions are only for further explaining the features and advantages of the present invention, rather than limiting the claims of the present invention.

[0143] In the present invention, the drugs, reagents and instruments used can all be purchased from the market.

[0144] Instruments:

[0145] The instruments used for liquid chromatograph detection are: Agilent 1260 Infinity Ⅱ, UV ultraviolet detector;

[0146] The instrument used for pH meter is: Mettler FE28;

[0147] The instrument used for weighing is: Mettler XSR 105 electronic analytical balance.

[0148] Test drugs:

[0149] Reference substance methylparaben (batch number: 100278 - 201906, purity 99.9%), purchased from the National Institutes for Food and Drug Control;

[0150] Reference substance propylparaben (batch number: 100444 - 202005, purity 99.9%), purchased from the National Institutes for Food and Drug Control;

[0151] Reference substance cetirizine hydrochloride (batch number: 100660 - 201803, purity 99.6%), purchased from the National Institutes for Food and Drug Control;

[0152] Potassium dihydrogen phosphate (analytical reagent, Chengdu Kelong Chemical Co., Ltd.);

[0153] Phosphoric acid (analytical reagent, Chengdu Kelong Chemical Co., Ltd.);

[0154] Acetonitrile (chromatographic pure, MORELLK), water is ultrapure water;

[0155] Cetirizine hydrochloride oral solution: produced by Sichuan Jianneng Pharmaceutical Co., Ltd.

[0156] Example 1: Specificity of the method of the present invention

[0157] 1. Solution preparation:

[0158] Blank solvent: mobile phase.

[0159] Blank excipient solution 1: Precisely measure 5 mL of blank excipient (without cetirizine hydrochloride, that is, prepare a solution composed of all other components except cetirizine hydrochloride in the order of the process prescription), place it in a 100 mL volumetric flask, dilute it to the mark with the mobile phase, and shake well to obtain.

[0160] Blank excipient solution 2: Precisely measure 5 mL of blank excipient (without preservatives methylparaben and propylparaben, that is, prepare a solution composed of all other components except methylparaben and propylparaben in the order of the process prescription), place it in a 100 mL volumetric flask, dilute it to the mark with the mobile phase, and shake well to obtain.

[0161] Stock solution of methylparaben reference substance: Take 27 mg of methylparaben reference substance, accurately weigh it, place it in a 20 mL volumetric flask, dissolve it with the mobile phase and dilute it to the mark, and shake well to obtain.

[0162] Stock solution of cetirizine hydrochloride reference substance: Take 20 mg of cetirizine hydrochloride reference substance, accurately weigh it, place it in a 20 mL volumetric flask, dissolve it with the mobile phase and dilute it to the mark, and shake well to obtain.

[0163] Propylparaben reference stock solution: Take 30 mg of propylparaben reference substance, weigh it accurately, place it in a 20 mL volumetric flask, dissolve it with the mobile phase and dilute it to the mark, and shake well. Then accurately measure 2 mL, place it in a 20 mL volumetric flask, dissolve it with the mobile phase and dilute it to the mark, and shake well, and you will get it.

[0164] Methylparaben positioning solution: Accurately measure 1 mL of methylparaben reference stock solution, place it in a 20 mL volumetric flask, dilute it to the mark with the mobile phase, and shake well, and you will get it (each 1 mL contains 67.5 μg of methylparaben).

[0165] Propylparaben positioning solution: Accurately measure 1 mL of propylparaben reference stock solution, place it in a 20 mL volumetric flask, dilute it to the mark with the mobile phase, and shake well, and you will get it (each 1 mL contains 7.5 μg of propylparaben).

[0166] Cetirizine hydrochloride positioning solution: Accurately measure 1 mL of cetirizine hydrochloride reference stock solution, place it in a 20 mL volumetric flask, dilute it to the mark with the mobile phase, and shake well, and you will get it (each 1 mL contains 50 μg of cetirizine hydrochloride).

[0167] Reference solution: Accurately measure 5 mL each of methylparaben reference stock solution, propylparaben reference stock solution, and cetirizine hydrochloride reference stock solution, place them in a 100 mL volumetric flask, dilute it to the mark with the mobile phase, and shake well, and you will get it (each 1 mL contains 50 μg of cetirizine hydrochloride, 67.5 μg of methylparaben, and 7.5 μg of propylparaben).

[0168] Test solution: Use a volumetric pipette to accurately measure 5 mL of this product, place it in a 100 mL volumetric flask, dilute it to the mark with the mobile phase, and shake well, and you will get it.

[0169] 2. Test results

[0170] Respectively take the blank solvent, blank excipient solution 1, blank excipient solution 2, test solution, reference solution, and each positioning solution and send them into the liquid chromatograph for detection to examine the retention time of each component.

[0171] Detection conditions:

[0172] Chromatographic column: Welch Xtimate C18, 250 mm × 4.6 mm, 5 μm;

[0173] Mobile phase: Adjust the pH of 0.1 mol / L potassium dihydrogen phosphate solution to 3.7 with phosphoric acid, and then mix it with acetonitrile in a volume ratio of 65:35 to obtain the mobile phase;

[0174] Mobile phase flow rate: 1.0 mL / min;

[0175] Chromatographic column temperature: 30 °C;

[0176] Detection wavelength: 232 nm;

[0177] Sample injection volume: 20 μL;

[0178] Elution mode: isocratic elution.

[0179] Among them, the chromatograms of the blank solvent, blank excipient solution 1, blank excipient solution 2, reference solution, and test solution are respectively as Figures 1-5 shown.

[0180] The test results are shown in Table 1:

[0181] Table 1: Specificity test results

[0182]

[0183] The results show that the blank solvent, blank excipient solution 1, and blank excipient solution 2 do not interfere with the determination, and the resolution of methylparaben, propylparaben, and cetirizine hydrochloride is greater than 1.5, indicating good specificity of the present invention.

[0184] Example 2: Quantitation limit and precision of quantitation limit

[0185] 1. Solution preparation:

[0186] Stock solution of methylparaben reference substance: same as Example 1.

[0187] Stock solution of propylparaben reference substance: same as Example 1.

[0188] Diluent: Accurately measure appropriate amounts of the stock solution of methylparaben reference substance and the stock solution of propylparaben reference substance, and gradually dilute with the mobile phase to a solution with a signal-to-noise ratio ≥ 10 as the quantitation limit solution.

[0189] Inject the quantitation limit solution (inject 6 needles in parallel) into the liquid chromatograph for detection (detection conditions are the same as in Example 1).

[0190] 2. Test results:

[0191] The test results are shown in Table 2-3:

[0192] Table 2: Test results of quantitation limit

[0193]

[0194] Table 3: Precision test results of quantitation limit

[0195]

[0196] The results show that the quantitation limit of methylparaben is 0.033 μg / mL, and the quantitation limit of propylparaben is 0.154 μg / mL.

[0197] Example 3: Linearity and Range of the Method of the Present Invention

[0198] 1. Solution Preparation:

[0199] Reference Stock Solution (1): Weigh 30 mg of propylparaben reference substance accurately, place it in a 20 mL volumetric flask, dissolve it with the mobile phase and dilute it to the mark, shake well to obtain.

[0200] Reference Stock Solution (2): Weigh 67.5 mg of methylparaben reference substance accurately, place it in a 100 mL volumetric flask, then accurately add 5 mL of Reference Stock Solution (1), dissolve it with the mobile phase and dilute it to the mark, shake well to obtain.

[0201] Reference Stock Solution (3): Weigh 25 mg of cetirizine hydrochloride reference substance accurately, place it in a 50 mL volumetric flask, dissolve it with the mobile phase and dilute it to the mark, shake well to obtain.

[0202] Each linear solution: Accurately measure 2.5 mL, 4.0 mL, 5.0 mL, 6.0 mL, 7.5 mL of Reference Stock Solution (2) respectively, place them in 5 50 mL volumetric flasks, then accurately measure 2.5 mL, 4.0 mL, 5.0 mL, 6.0 mL, 7.5 mL of Reference Stock Solution (3) respectively, place them in the above 5 50 mL volumetric flasks, dilute to the mark with the mobile phase, and mix well to obtain.

[0203] 2. Test Results

[0204] Inject the above each linear solution into the liquid chromatograph for detection (the detection conditions are the same as those in Example 1), and the results are shown in Table 4 - 6 and Figures 6-8 .

[0205] Table 4: Results of the Linearity Test of Cetirizine Hydrochloride

[0206]

[0207] Table 5: Results of the Linearity Test of Methylparaben

[0208]

[0209] Table 6: Results of the Linearity Test of Propylparaben

[0210]

[0211] The results show that methylparaben, propylparaben, and cetirizine hydrochloride have good linearity in the limit concentration range of 50% - 150%.

[0212] Example 4: Precision of the Method of the Present Invention

[0213] 1. Solution Preparation:

[0214] Reference solution: The same as in Example 1, prepared in the same method for 2 portions.

[0215] Test solution: The same as in Example 1, prepared in the same method for 6 portions.

[0216] 2. Test results

[0217] For 2 portions of the reference solution, one portion was injected in parallel for 5 times and the other portion was injected in parallel for 2 times, and each test solution was injected once, and then sent into the liquid chromatograph for detection (the detection conditions were the same as in Example 1), and the results are shown in Table 7-8.

[0218] Table 7: Results of precision test for cetirizine hydrochloride

[0219]

[0220] Table 8: Results of precision test for methylparaben and propylparaben

[0221]

[0222] The results showed that the average content of cetirizine hydrochloride in the test solution was 97.7%, and the relative standard deviation RSD was 0.89%; the average content of methylparaben was 98.7%, and the relative standard deviation was 0.45%; the average content of propylparaben was 96.3%, and the relative standard deviation was 0.66%; it was confirmed that the precision of the method of the present invention was good.

[0223] Example 5: Accuracy of the method of the present invention

[0224] 1. Solution preparation:

[0225] Stock solution of cetirizine hydrochloride reference substance: Take 100 mg of cetirizine hydrochloride reference substance, weigh accurately, place it in a 100 mL volumetric flask, dissolve it with the mobile phase and dilute to the mark, shake well, and you will get it.

[0226] Stock solution of methylparaben reference substance: Take 135 mg of methylparaben reference substance, weigh accurately, place it in a 100 mL volumetric flask, dissolve it with the mobile phase and dilute to the mark, shake well, and you will get it.

[0227] Stock solution of propylparaben reference substance: Take 30 mg of propylparaben reference substance, weigh accurately, place it in a 20 mL volumetric flask, dissolve it with the mobile phase and dilute to the mark. Then accurately measure 10 mL and place it in a 100 mL volumetric flask, dilute it to the mark with the mobile phase, shake well, and you will get it.

[0228] Reference solution: Accurately measure 5 mL each of the stock solution of cetirizine hydrochloride reference substance, the stock solution of methylparaben reference substance, and the stock solution of propylparaben reference substance, place them in a 100 mL volumetric flask, dilute to the mark with the mobile phase, shake well, and you will get it. Prepared in the same method for 2 portions.

[0229] 50% Cetirizine Hydrochloride Accuracy Solution: Precisely measure 5 mL of blank excipient solution 1, transfer it to a 100 mL volumetric flask, then precisely measure 2.5 mL of the cetirizine hydrochloride reference stock solution, dilute it to the mark with the mobile phase, and prepare 3 portions in the same manner.

[0230] 100% Cetirizine Hydrochloride Accuracy Solution: Precisely measure 5 mL of blank excipient solution 1, transfer it to a 100 mL volumetric flask, then precisely measure 5 mL of the cetirizine hydrochloride reference stock solution respectively, dilute it to the mark with the mobile phase, and prepare 3 portions in the same manner.

[0231] 150% Cetirizine Hydrochloride Accuracy Solution: Precisely measure 5 mL of blank excipient solution 1, transfer it to a 100 mL volumetric flask, then precisely measure 7.5 mL of the cetirizine hydrochloride reference stock solution respectively, dilute it to the mark with the mobile phase, and prepare 3 portions in the same manner.

[0232] 50% Methylparaben and Propylparaben Accuracy Solution: Precisely measure 5 mL of blank excipient solution 2, transfer it to a 100 mL volumetric flask, then precisely measure 2.5 mL of the methylparaben reference stock solution and the propylparaben reference stock solution respectively, dilute it to the mark with the mobile phase, and prepare 3 portions in the same manner.

[0233] 100% Methylparaben and Propylparaben Accuracy Solution: Precisely measure 5 mL of blank excipient solution 2, transfer it to a 100 mL volumetric flask, then precisely measure 5 mL of the methylparaben reference stock solution and the propylparaben reference stock solution respectively, dilute it to the mark with the mobile phase, and prepare 3 portions in the same manner.

[0234] 150% Methylparaben and Propylparaben Accuracy Solution: Precisely measure 5 mL of blank excipient solution 2, transfer it to a 100 mL volumetric flask, then precisely measure 7.5 mL of the methylparaben reference stock solution and the propylparaben reference stock solution respectively, dilute it to the mark with the mobile phase, and prepare 3 portions in the same manner.

[0235] 2. Test Results:

[0236] Inject two portions of the reference solution, inject 5 needles in parallel for one portion and 2 needles in parallel for the other portion, and inject one needle for each accuracy solution into the liquid chromatograph for detection (the detection conditions are the same as in Example 1), and the results are shown in Tables 9 - 11 respectively.

[0237] Table 9: Test Results of Methylparaben Accuracy

[0238]

[0239] Table 10: Test Results of Propylparaben Accuracy

[0240]

[0241] Table 11: Test Results of Cetirizine Hydrochloride Accuracy

[0242]

[0243] The results showed that the recovery rate of cetirizine hydrochloride was 98.10% - 98.71%; the recovery rate of methylparaben was 98.08% - 100.59%, and the recovery rate of propylparaben was 99.07% - 100.87%, indicating that the method had high accuracy.

[0244] Example 6: Solution stability

[0245] 1. Solution preparation:

[0246] Reference substance solution: The same as in Example 1.

[0247] Test solution: The same as in Example 1.

[0248] 2. Test results:

[0249] After storing the reference substance solution and the test solution at room temperature for 0h, 4h, 8h, 12h, 24h, 48h, and 72h respectively, they were separately sent into the liquid chromatograph for detection (the detection conditions were the same as in Example 1), and the results were shown in Table 12 respectively.

[0250] Table 12: Results of solution stability test

[0251]

[0252] The results showed that both the reference substance solution and the test solution were stable within 72h, indicating good durability of the method of the present invention.

[0253] Example 7:

[0254] 1. Solution preparation:

[0255] Reference substance solution: The same as in Example 1.

[0256] 2. Test results:

[0257] The reference substance solution was sent into the liquid chromatograph for detection, and the test results under different chromatographic conditions were examined. The chromatograms were as shown in Figures 9-14 (the detection conditions were the same as in Example 1 except for the mobile phase ratio).

[0258] Table 13: Results of chromatographic condition test

[0259]

[0260] The results showed that for the reference solution with a mobile phase ratio of 65:35 (volume ratio), most of the chromatographic peaks of each component on different chromatographic columns were baseline-separated, with better resolution. However, when the mobile phase volume ratio was 60:40, baseline separation was not achieved. This proved that the mobile phase with the above-mentioned ratio combination in the present invention was beneficial to the detection effect. In addition, the mobile phase volume ratio of 65:35 was more suitable for most chromatographic columns, indicating good durability of the method of the present invention.

[0261] Example 8

[0262] Take three batches of cetirizine hydrochloride oral solution and detect them according to the test method of the present invention. The results are shown in the following table.

[0263] Table 14: Detection results of three batches of cetirizine hydrochloride oral solution

[0264]

[0265] Cetirizine hydrochloride, methylparaben, and propylparaben in this article are three different substances in the formulation prescription. The feeding amounts in the process are different. That is, the theoretical concentration (labeling amount) of cetirizine hydrochloride is 1 mg / mL, the labeling amount of methylparaben is 1.35 mg / mL, and the theoretical concentration (labeling amount) of propylparaben is 0.15 mg / mL. According to the formula content (%) = F × A R × V R / (V × C) × 100%, taking the batch No. 20230401 in Table 14 as an example: where the measured amount (mg / mL) = F × A R × V R / V. For example, the measured cetirizine hydrochloride is 0.992 mg / mL, methylparaben is 1.35 mg / mL, and propylparaben is 0.1466 mg / mL. Correspondingly, the content of cetirizine hydrochloride (%) = 0.992 / 1 × 100% = 99.2%, the content of methylparaben (%) = 1.35 / 1.35 × 100% = 100.0%, and the content of propylparaben (%) = 0.1466 / 0.15 × 100% = 97.7%. And the general limit for content determination in the Chinese Pharmacopoeia is generally specified as "This product should contain ××% - ××% of the labeled amount". For example, "This product should contain 95% - 105% of the labeled amount of cetirizine hydrochloride, and methylparaben and propylparaben should contain 90% - 110% of the labeled amount".

[0266] The results in Table 14 showed that using this method, the methylparaben, propylparaben, and cetirizine hydrochloride in the cetirizine hydrochloride oral solution could be accurately measured, and the blank excipients did not interfere with the detection.

[0267] Specific examples are used in the text to illustrate the principles and implementation modes of the present invention. The description of the above embodiments is only used to help understand the method and its core idea of the present invention, including the best mode, and also enables any person skilled in the art to practice the present invention, including manufacturing and using any device or system, and implementing any combined method. It should be noted that for those of ordinary skill in the art in the technical field, without departing from the principle of the present invention, several improvements and modifications can be made to the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention. The protection scope of the present invention patent is defined by the claims and may include other embodiments that can be conceived by those skilled in the art. If these other embodiments have structural elements similar to the literal description of the claims, or if they include equivalent structural elements that have no substantial difference from the literal description of the claims, then these other embodiments should also be included within the scope of the claims.

Claims

1. A method for determining the content of cetirizine hydrochloride and each preservative in cetirizine hydrochloride oral solution, characterized in that, It includes the following steps: A) Prepare the test sample solution: Precisely measure 5 mL of this product with a volumetric pipette of the specified capacity, place it in a 100-mL volumetric flask, dilute it to the mark with the mobile phase, and shake well to obtain the test sample solution; B) Prepare the reference substance mixed solution: Prepare the stock solution of cetirizine hydrochloride reference substance: Take 20 mg of cetirizine hydrochloride reference substance, accurately weigh it, place it in a 20-mL volumetric flask, dissolve it with the mobile phase and dilute it to the mark, and shake well to obtain it; Prepare the stock solution of methylparaben reference substance: Take 27 mg of methylparaben reference substance, accurately weigh it, place it in a 20-mL volumetric flask, dissolve it with the mobile phase and dilute it to the mark, and shake well to obtain it; Prepare the stock solution of propylparaben reference substance: Take 30 mg of propylparaben reference substance, accurately weigh it, place it in a 20-mL volumetric flask, dissolve it with the mobile phase and dilute it to the mark, and shake well to obtain the initial solution; then precisely measure 2 mL of the said initial solution, place it in a 20-mL volumetric flask, dissolve it with the mobile phase and dilute it to the mark, and shake well to obtain it; Precisely measure 5 mL each of the stock solution of cetirizine hydrochloride reference substance, the stock solution of methylparaben reference substance, and the stock solution of propylparaben reference substance, place them in a 100-mL volumetric flask, dilute it to the mark with the mobile phase, and shake well to obtain the reference substance mixed solution; C) Liquid chromatography test: Precisely measure the test sample solution and the reference substance mixed solution, and inject them into the liquid chromatograph respectively for liquid chromatography test to obtain the chromatogram of the test sample solution and the chromatogram of the reference substance mixed solution respectively; then according to the external standard method, obtain the content of cetirizine hydrochloride, the content of methylparaben preservative, and the content of propylparaben preservative in the cetirizine hydrochloride oral solution respectively; Among them, the conditions of the said liquid chromatography test are as follows: Chromatographic column: Octadecylsilane chemically bonded silica packing material; Mobile phase: Adjust the pH of a 0.1 mol / L potassium dihydrogen phosphate solution to 3.7 with phosphoric acid, and then mix it with acetonitrile in a volume ratio of 65:35 to obtain the mobile phase; Mobile phase flow rate: 0.8 - 1.2 mL / min; Chromatographic column temperature: 25 - 35 °C; Detection wavelength: 232 nm; Injection volume: 20 μL; Elution mode: Isocratic elution; Among them, there is no order limit for steps A) and B).

2. The method according to claim 1, characterized in that In step A), the concentration of the said test sample solution is: Each 1 mL of the test sample solution contains 50 μg of cetirizine hydrochloride.

3. The method according to claim 1, characterized in that, In step B), the concentration of the said reference substance mixed solution is: Each 1 mL of the reference substance mixed solution contains 50 μg of cetirizine hydrochloride, 67.5 μg of methylparaben, and 7.5 μg of propylparaben.

4. The method according to claim 1, characterized in that, In step C), the said external standard method is calculated through the following formulas (1) - (2): Correction factor: In formula (1): F: Correction factor; m s : Sampling amount of each reference substance of cetirizine hydrochloride, methylparaben or propylparaben, mg; p: Purity of each reference substance of cetirizine hydrochloride, methylparaben, or propylparaben; V s : dilution volume of each reference substance to the reference substance mixed solution, mL; A s : The peak area of cetirizine hydrochloride, methylparaben or propylparaben in the reference substance mixed solution; Component content: In formula (2): W: Content of cetirizine hydrochloride, methylparaben, or propylparaben in the cetirizine hydrochloride oral solution, %; F: Correction factor calculated from formula (1); A R : The peak area of cetirizine hydrochloride, methylparaben or propylparaben in the test solution; V R : Dilution volume of the test solution, mL; V: Volume of the cetirizine hydrochloride oral solution taken in the test sample solution, mL; C: Labeled amount of cetirizine hydrochloride, methylparaben, or propylparaben in the cetirizine hydrochloride oral solution of this product, mg / mL.

5. The method according to claim 4, characterized in that, In formula (2), the parameter C is as follows: Cetirizine Hydrochloride Oral Solution The labeled amount of cetirizine hydrochloride in this product is 1 mg / mL, the labeled amount of methylparaben is 1.35 mg / mL, and the labeled amount of propylparaben is 0.15 mg / mL.

6. The method according to claim 1, characterized in that The chromatographic column is one of Agilent SB / XDB / EXTENDC18, Welch Xtimate, and MORHCHEM Caprisil C18-P.

7. The method according to claim 1 or 5, characterized in that The specifications of the chromatographic column are: length 250 mm, inner diameter 4.6 mm, and packing material particle size 5 μm.

8. The method according to claim 1, characterized in that The flow rate of the mobile phase is 1.0 mL / min.

9. The method according to claim 1, wherein The temperature of the chromatographic column is 30 °C.

10. The method according to claim 1, characterized in that, In step C), the liquid chromatography test is a high performance liquid chromatography test.

Images