CN117665181A - Method for detecting ammonia in methylamine alcohol - Google Patents
Method for detecting ammonia in methylamine alcohol Download PDFInfo
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- CN117665181A CN117665181A CN202311564555.4A CN202311564555A CN117665181A CN 117665181 A CN117665181 A CN 117665181A CN 202311564555 A CN202311564555 A CN 202311564555A CN 117665181 A CN117665181 A CN 117665181A
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- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 title claims abstract description 126
- BAVYZALUXZFZLV-UHFFFAOYSA-N Methylamine Chemical compound NC BAVYZALUXZFZLV-UHFFFAOYSA-N 0.000 title claims abstract description 74
- 229910021529 ammonia Inorganic materials 0.000 title claims abstract description 63
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 title claims abstract description 37
- 238000000034 method Methods 0.000 title claims description 16
- 239000000243 solution Substances 0.000 claims description 64
- 239000012490 blank solution Substances 0.000 claims description 23
- 239000011550 stock solution Substances 0.000 claims description 15
- 239000012085 test solution Substances 0.000 claims description 13
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 12
- VHUUQVKOLVNVRT-UHFFFAOYSA-N Ammonium hydroxide Chemical compound [NH4+].[OH-] VHUUQVKOLVNVRT-UHFFFAOYSA-N 0.000 claims description 11
- 235000011114 ammonium hydroxide Nutrition 0.000 claims description 11
- IAZDPXIOMUYVGZ-UHFFFAOYSA-N Dimethylsulphoxide Chemical compound CS(C)=O IAZDPXIOMUYVGZ-UHFFFAOYSA-N 0.000 claims description 8
- 238000007865 diluting Methods 0.000 claims description 6
- 239000012088 reference solution Substances 0.000 claims description 6
- 239000013558 reference substance Substances 0.000 claims description 5
- 238000002347 injection Methods 0.000 claims description 4
- 239000007924 injection Substances 0.000 claims description 4
- 239000000203 mixture Substances 0.000 claims description 4
- 239000012159 carrier gas Substances 0.000 claims description 3
- 238000004817 gas chromatography Methods 0.000 claims description 3
- 238000010438 heat treatment Methods 0.000 claims description 3
- 238000001514 detection method Methods 0.000 abstract description 14
- 239000003814 drug Substances 0.000 abstract description 3
- 238000004458 analytical method Methods 0.000 abstract description 2
- 239000003085 diluting agent Substances 0.000 description 18
- 239000000523 sample Substances 0.000 description 15
- 238000005303 weighing Methods 0.000 description 14
- 230000035945 sensitivity Effects 0.000 description 5
- LZPZPHGJDAGEJZ-AKAIJSEGSA-N regadenoson Chemical compound C1=C(C(=O)NC)C=NN1C1=NC(N)=C(N=CN2[C@H]3[C@@H]([C@H](O)[C@@H](CO)O3)O)C2=N1 LZPZPHGJDAGEJZ-AKAIJSEGSA-N 0.000 description 4
- 229960003614 regadenoson Drugs 0.000 description 4
- 238000012360 testing method Methods 0.000 description 4
- 238000010790 dilution Methods 0.000 description 3
- 239000012895 dilution Substances 0.000 description 3
- 239000007788 liquid Substances 0.000 description 3
- 238000005259 measurement Methods 0.000 description 3
- 238000002798 spectrophotometry method Methods 0.000 description 3
- 239000008186 active pharmaceutical agent Substances 0.000 description 2
- 229940088679 drug related substance Drugs 0.000 description 2
- 238000002474 experimental method Methods 0.000 description 2
- 239000007789 gas Substances 0.000 description 2
- 238000003908 quality control method Methods 0.000 description 2
- 230000003252 repetitive effect Effects 0.000 description 2
- YGSDEFSMJLZEOE-UHFFFAOYSA-N salicylic acid Chemical compound OC(=O)C1=CC=CC=C1O YGSDEFSMJLZEOE-UHFFFAOYSA-N 0.000 description 2
- 239000012488 sample solution Substances 0.000 description 2
- 238000000926 separation method Methods 0.000 description 2
- VRZJGENLTNRAIG-UHFFFAOYSA-N 4-[4-(dimethylamino)phenyl]iminonaphthalen-1-one Chemical compound C1=CC(N(C)C)=CC=C1N=C1C2=CC=CC=C2C(=O)C=C1 VRZJGENLTNRAIG-UHFFFAOYSA-N 0.000 description 1
- 244000088401 Pyrus pyrifolia Species 0.000 description 1
- 235000001630 Pyrus pyrifolia var culta Nutrition 0.000 description 1
- 238000010521 absorption reaction Methods 0.000 description 1
- 239000003153 chemical reaction reagent Substances 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 229940079593 drug Drugs 0.000 description 1
- 238000004128 high performance liquid chromatography Methods 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 238000011835 investigation Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000012946 outsourcing Methods 0.000 description 1
- FJKROLUGYXJWQN-UHFFFAOYSA-N papa-hydroxy-benzoic acid Natural products OC(=O)C1=CC=C(O)C=C1 FJKROLUGYXJWQN-UHFFFAOYSA-N 0.000 description 1
- 239000012450 pharmaceutical intermediate Substances 0.000 description 1
- 238000011002 quantification Methods 0.000 description 1
- 229960004889 salicylic acid Drugs 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 230000002194 synthesizing effect Effects 0.000 description 1
- 229910021642 ultra pure water Inorganic materials 0.000 description 1
- 239000012498 ultrapure water Substances 0.000 description 1
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
- Y02A50/00—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE in human health protection, e.g. against extreme weather
- Y02A50/20—Air quality improvement or preservation, e.g. vehicle emission control or emission reduction by using catalytic converters
Landscapes
- Investigating Or Analyzing Non-Biological Materials By The Use Of Chemical Means (AREA)
Abstract
The invention belongs to the technical field of medicine analysis, in particular to a detection method of ammonia in methylamine alcohol, which provides a convenient, efficient and accurate detection method for solving the detection problem of ammonia in methylamine alcohol.
Description
Technical Field
The invention belongs to the technical field of medicine analysis, and particularly relates to a detection method of ammonia in methylamine alcohol.
Background
The methylamine alcohol has a chemical formula of CH5NO, is colorless liquid with ammonia odor at normal temperature, is widely used in the pharmaceutical intermediate industry, is a key material for synthesizing regadenoson, and is used for preparing pharmaceutical compositionsIn the process for preparing the methylamine alcohol drug substance, ammonia may be generated in the methylamine alcohol, which affects the quality of the methylamine alcohol and finally affects the regadenoson drug substance. Ammonia is present in methylamine alcohol, and the corresponding impurity I may be produced in the product of the regadenoson) The necessity of product studies is increased and if the ammonia level is controlled from the methylamine alcohol feed, the study of the regadenoson product can be reduced.
At present, for the ammonia detection method, including Nashi reagent spectrophotometry, salicylic acid spectrophotometry, indophenol blue spectrophotometry and the like, the specificity of the method is not strong, the quantitative accuracy is poor, and because the ammonia ultraviolet absorption is weak, the invention adopts gas phase TCD detection, has better response, and can well quantify the actual content of ammonia in methylamine alcohol. The method for detecting the ammonia in the methylamine alcohol has fewer literature reports, the invention firstly discloses a gas chromatography method for detecting the ammonia content in the methylamine alcohol, reduces the detection cost, and provides a convenient, efficient and accurate detection method for solving the problem of detecting the ammonia in the methylamine alcohol.
Disclosure of Invention
The invention provides a method for detecting ammonia in methylamine alcohol, which is convenient, efficient and accurate for solving the problem of detecting ammonia in methylamine alcohol.
In order to achieve the above purpose, the present invention provides the following technical solutions:
a method for detecting ammonia in methylamine alcohol, the method comprising the steps of:
(1) Preparing solutions, and respectively preparing a blank solution, a reference solution, a quantitative limiting solution, a selective solution, a water positioning solution and a test solution.
(2) The measuring method comprises the following steps: determining ammonia content in methylamine alcohol by gas chromatography, respectively adding blank solution, reference solution, quantitative limiting solution, selective solution, water positioning solution and test solution after the system is stable, and recording chromatogram;
the chromatographic conditions are as follows: ultra-high inertia weak polar capillary column, column temperature: maintaining at 40deg.C for 10min, heating to 250deg.C at 20deg.C/min, and maintaining for 5min; sample inlet temperature: 200 ℃; detector type: TCD (thermal conductivity detector), detector temperature: 250 ℃; split ratio: 30:1, a step of; carrier gas: n2; flow rate: 1.5ml/min; sample injection volume: 5 μl.
Further, the chromatographic column is: an Agilent CP-Volamine 60 mx0.32 mm or equivalent polarity column, or equivalent potency column; the blank solution is dimethyl sulfoxide; the control solution: placing a proper amount of ammonia stock solution into a volumetric flask, adding a blank solution to dilute to a scale, and shaking uniformly; the ammonia stock solution: placing a proper amount of ammonia water into a volumetric flask, adding a blank solution to dilute to a scale, and shaking uniformly; the quantitative limiting solution: placing a proper amount of reference substance solution into a volumetric flask, adding blank solution, diluting to scale, and shaking; water positioning solution: placing a proper amount of water into a volumetric flask, adding a blank solution to dilute to a scale, and shaking uniformly; test solution: placing a proper amount of methylamine alcohol sample into a volumetric flask, adding a blank solution to dilute to a scale, and shaking uniformly; selective solution: and (3) taking a proper amount of methylamine alcohol sample and a proper amount of ammonia stock solution, placing the mixture into a volumetric flask, adding a blank solution, diluting to a scale, and shaking uniformly.
The invention provides a convenient, efficient and accurate detection method for detecting ammonia in methylamine alcohol, which can be used for quality control of methylamine alcohol, and can detect the ammonia content in methylamine alcohol, thereby effectively guaranteeing medication safety and facilitating quality control of methylamine alcohol.
Drawings
FIG. 1 is a blank solution chart of the present invention
FIG. 2 is a graph of a control solution according to the present invention
FIG. 3 is a quantitative limiting solution graph of the present invention
FIG. 4 is a diagram of an aqueous positioning solution according to the present invention
FIG. 5 is a graph of a test solution according to the present invention
FIG. 6 is a graph of a selective solution according to the invention
Description of the embodiments
The invention is further illustrated by the following examples, which are not intended to be limiting.
Example 1
Preparing a solution:
dilution liquid: dimethyl sulfoxide;
blank solution: a dilution liquid;
ammonia stock solution: taking about 3.0g of ammonia water, precisely weighing, placing into a 25ml measuring flask, adding diluent to dilute to a scale, and shaking uniformly. ( Concentration of ammonia water: 0.12g/ml, corresponding to ammonia concentration: 0.03g/ml )
Control solution: precisely measuring 2.0ml of ammonia stock solution, placing into a 20ml measuring flask, adding diluent to dilute to a scale, and shaking uniformly. ( Concentration of ammonia water: 12mg/ml, corresponding to ammonia concentration: 3mg/ml )
Quantitative limiting solution: precisely measuring 2.0ml of reference substance solution, placing into a 20ml measuring flask, adding diluent, diluting to scale, and shaking. ( Concentration of ammonia water: 1.2mg/ml, corresponding to ammonia concentration: 0.3mg/ml )
Water positioning solution: taking about 2.25g of water, precisely weighing, placing into a 25ml measuring flask, adding diluent to dilute to scale, and shaking; weighing the 2.0ml, placing into a 20ml measuring flask, adding diluent, diluting to scale, and shaking. (concentration: 9 mg/ml)
Test solution: taking about 12g of methylamine alcohol sample, precisely weighing, placing into a 20ml volumetric flask, adding diluent to dilute to scale, and shaking uniformly. (concentration: 0.6 g/ml)
Selective solution: taking about 12g of methylamine alcohol sample, precisely weighing, placing into a 20ml volumetric flask, precisely weighing 2.0ml of ammonia stock solution, placing into the volumetric flask, adding diluent to dilute to a scale, and shaking uniformly. ( Concentration: methylamine alcohol 0.6g/ml, ammonia concentration: 12mg/ml, corresponding to ammonia concentration: 3mg/ml )
Remarks: the ammonia content in the ammonia water is 25%.
Dimethyl sulfoxide: HPLC; ammonia (25%): outsourcing; water: ultrapure water;
(2) Chromatographic conditions:
chromatographic column: preparing a gas chromatograph of a thermal conductivity detector and a direct sample injector; ultra-high inert weak polar capillary column (e.g. Agilent CP-Volamine 60 m. Times.0.32 mm or chromatographic column with equivalent polarity)
Column temperature: maintaining at 40deg.C for 10min, heating to 250deg.C at 20deg.C/min, and maintaining for 5min;
sample inlet temperature: 200 ℃; detector temperature: 250 ℃;
split ratio: 30:1, a step of; carrier gas: n2;
flow rate: 1.5ml/min; sample injection volume: 5 μl.
(3) The measuring method comprises the following steps:
after the system is stable, a blank solution 1 needle (1 to 3 needles can be added if necessary), a reference solution 1 needle, a quantitative limiting solution 1 needle, a water positioning solution 1 needle, a test solution 1 needle, a selective solution 1 needle, a chromatogram is recorded, and the S/N value of an ammonia peak in the quantitative limiting solution is more than or equal to 10.
Ammonia (%) = (RU/Rs) × (Cs/CU) ×100
Wherein: RU: testing the peak area of ammonia in the solution map;
rs: peak area of ammonia in the reference solution profile;
cs: concentration of ammonia in the reference solution (mg/ml);
CU: concentration of test solution (mg/ml).
And (3) result judgment:
example 2: system applicability
System applicability is achieved by measuring the sensitivity of ammonia in a sensitivity solution; the S/N value of ammonia is required to be more than or equal to 10; taking about 3.0g of ammonia water, precisely weighing, placing into a 25ml measuring flask, adding diluent to dilute to a scale, and shaking uniformly; precisely measuring 2.0ml of the solution, placing into a 20ml measuring flask, adding diluent to dilute to scale, and shaking uniformly; precisely measuring 2.0ml of the solution, placing the solution into a 20ml measuring flask, adding diluent to dilute to a scale, and shaking uniformly to obtain a sensitivity solution. Sample injection measurement is carried out according to the chromatographic conditions in the example 1, a chromatogram is recorded, and the test shows that the S/N value of ammonia in a sensitivity solution is more than 10; can meet the requirement of system applicability.
Example 3: specialization of
The specificity is that whether the blank solution has interference to ammonia detection is measured, and the separation degree between ammonia and adjacent peaks should meet the requirement; taking about 3.0g of ammonia water, precisely weighing, placing into a 25ml measuring flask, adding diluent to dilute to a scale, and shaking uniformly; as an ammonia stock solution. Taking about 12g of a methylamine alcohol sample, precisely weighing, placing the methylamine alcohol sample into a 20ml volumetric flask, precisely weighing 2.0ml of ammonia stock solution, placing the ammonia stock solution into the volumetric flask, adding a diluent to dilute to a scale, and shaking uniformly to obtain an alternative solution;
the chromatographic conditions of example 1 were followed, the blank solution had no interference with methylamine alcohol detection, and the separation between ammonia and adjacent peaks in the selective solution was not less than 1.5.
Example 4: limit of detection and limit of quantification
The detection limit is obtained by detecting that the ratio of the response signal of each component to the noise is more than or equal to 3, and the quantitative limit is obtained by detecting that the ratio of the response signal of each component to the noise is more than or equal to 10; taking about 3.0g of ammonia water, precisely weighing, placing into a 25ml measuring flask, adding diluent to dilute to a scale, and shaking uniformly; precisely measuring 2.0ml of the solution, placing into a 20ml measuring flask, adding diluent to dilute to scale, and shaking uniformly; precisely measuring 2.0ml of the solution, placing the solution into a 20ml measuring flask, adding diluent to dilute to a scale, and shaking uniformly to obtain the LOQ solution. Taking 5ml of LOQ solution, placing the LOQ solution into a 10ml measuring flask, and adding diluent to dilute to a scale to obtain LOD solution; after the system is stable, the chromatographic conditions of the example 1 are adopted to detect, the chromatograms are recorded, and experiments show that the S/N value of ammonia in the LOQ solution is more than 10, and the S/N value of ammonia in the LOD solution is more than 3, so that the method has good sensitivity.
Example 5: linearity of
Drawing a curve by taking the concentration as an abscissa and the peak area as an ordinate at 6 concentration points of ammonia in the LOQ-150% index concentration range, wherein the curve is required to be linear in the LOQ-150% index concentration range, the linear correlation coefficient R2 of the curve is more than or equal to 0.99, taking a proper amount of reference substance solution, respectively preparing into quantitative limit, 50%, 80%, 100%, 120% and 150% solutions, and detecting according to the chromatographic condition of the embodiment 1 after the system is stable; experiments show that the ammonia linearity is good in the LOQ-150% index concentration range, and the linear correlation coefficient R2 of the curve is more than or equal to 0.99.
Example 6: precision of
Repeatability: testing 6 parts of test solution, wherein RSD of an ammonia measurement result in 6 parts of test solution is less than or equal to 2.0%; taking about 3.0g of ammonia water, precisely weighing, placing into a 25ml measuring flask, adding diluent to dilute to a scale, and shaking uniformly; as an ammonia stock solution. Taking about 12g of a methylamine alcohol sample, precisely weighing, placing the methylamine alcohol sample into a 20ml volumetric flask, precisely weighing 2.0ml of ammonia stock solution, placing the ammonia stock solution into the volumetric flask, adding a diluent for dilution to a scale, and shaking uniformly to obtain a repetitive solution; 6 parts of the mixture were prepared in the same manner, and after the system had stabilized, the mixture was examined under the chromatographic conditions of example 1. The test shows that the RSD of the ammonia measurement result in 6 parts of repetitive solution is less than or equal to 2.0%, and the method has good precision.
Example 7: solution stability
And (3) observing that the sample is injected after the test solution is placed for 0 hour, 24 hours and 48 hours at room temperature, wherein the ammonia content in the sample solution has no obvious change, which proves that the sample solution is relatively stable within 48 hours.
The accuracy of the method is ensured through investigation of properties such as system applicability, specificity, detection limit and quantitative limit, linearity, precision, solution stability and the like.
Claims (2)
1. A method for detecting ammonia in methylamine alcohol, which is characterized by comprising the following steps:
(1) Preparing solutions, namely preparing a blank solution, a reference substance solution, a quantitative limiting solution, a selective solution, a water positioning solution and a test solution respectively;
(2) The measuring method comprises the following steps: determining ammonia content in methylamine alcohol by gas chromatography, respectively adding blank solution, reference solution, quantitative limiting solution, selective solution, water positioning solution and test solution after the system is stable, and recording chromatogram;
the chromatographic conditions are as follows: ultra-high inertia weak polar capillary column, column temperature: maintaining at 40deg.C for 10min, heating to 250deg.C at 20deg.C/min, and maintaining for 5min; sample inlet temperature: 200 ℃; detector temperature: 250 ℃; split ratio: 30:1, a step of; carrier gas: n2; flow rate: 1.5ml/min; sample injection volume: 5 μl.
2. The method according to claim 1, characterized in that:
the chromatographic column is: an Agilent CP-Volamine 60 mx0.32 mm or equivalent polarity column, or equivalent potency column;
the blank solution is dimethyl sulfoxide;
the control solution: placing a proper amount of ammonia stock solution into a volumetric flask, adding a blank solution to dilute to a scale, and shaking uniformly;
the ammonia stock solution: placing a proper amount of ammonia water into a volumetric flask, adding a blank solution to dilute to a scale, and shaking uniformly;
the quantitative limiting solution: placing a proper amount of reference substance solution into a volumetric flask, adding blank solution, diluting to scale, and shaking;
water positioning solution: placing a proper amount of water into a volumetric flask, adding a blank solution to dilute to a scale, and shaking uniformly;
test solution: placing a proper amount of methylamine alcohol sample into a volumetric flask, adding a blank solution to dilute to a scale, and shaking uniformly;
selective solution: and (3) taking a proper amount of methylamine alcohol sample and a proper amount of ammonia stock solution, placing the mixture into a volumetric flask, adding a blank solution, diluting to a scale, and shaking uniformly.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311564555.4A CN117665181A (en) | 2023-11-22 | 2023-11-22 | Method for detecting ammonia in methylamine alcohol |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311564555.4A CN117665181A (en) | 2023-11-22 | 2023-11-22 | Method for detecting ammonia in methylamine alcohol |
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| Publication Number | Publication Date |
|---|---|
| CN117665181A true CN117665181A (en) | 2024-03-08 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
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| CN202311564555.4A Pending CN117665181A (en) | 2023-11-22 | 2023-11-22 | Method for detecting ammonia in methylamine alcohol |
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| CN (1) | CN117665181A (en) |
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2023
- 2023-11-22 CN CN202311564555.4A patent/CN117665181A/en active Pending
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