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Analytical Chemistry

Analytical chemistry is the subject for the method and basic principle of studying and identifying of the composition, status, structure of matter as well as determination of related content. It is an important branch of chemistry subject. Analytical chemistry plays an important role in not only its own development but also in various fields related to the chemistry. We can say that all the practice of any human activity involving chemical phenomena is inseparable from analytical chemistry. Now, people have developed various kinds of different analytical methods, which can be classified based on an analysis task, analysis object, the basis of the analysis, requirement of the analysis and sample dosage.

According to the analysis tasks, it can be divided into qualitative analysis, quantitative analysis and structural analysis. Task of qualitative analysis is to identify the elements, radicals, functional groups or compounds that constituting the substances; the task of the quantitative analysis is to determine the content of the related components in the sample; the task of structural analysis is to study the molecular structure or crystal structure of the material.

(1) According to the analysis objects, it can be divided into organic and inorganic analysis; the object for the inorganic analysis is inorganic substance; the object of organic analysis is organic substance. In the inorganic analysis, it is generally required to determine what elements, ions, radicals or compounds that constitutes the sample and measure the percentage of each component; and sometimes it is also necessary for determination of the crystal structure; in the organic analysis, it not only requires the identification of the constituent elements, but also, more importantly, should do the structure analysis and functional group analysis.
(2) According to whether the analysis is based on the physical properties or chemical properties of the substance, it can be divided into instrumental analysis and chemical analysis. Depending on the specific requirements, it can be divided into routine analysis, rapid analysis and arbitration Analysis. Routine analysis refers to the general daily laboratory production analysis, also known as conventional analysis; rapid analysis is a kind of routine analysis and is mainly applied to the control of the production process, demanding the report of the results in the shortest possible time with the error generally being allowed to be greater; arbitration analysis is needed when there is controversy in the analysis results from different institute, demanding related department to conduct accurate analysis using specific method in order to determine the accuracy of the results of the original analysis.
(3) According to the amount of the sample, it can be generally divided into constant (> 0.1g), semi-micro (0.01 ~ 0.1g) and trace (1 ~ 10mg) analysis.
(4) In the inorganic qualitative chemical analysis, people generally apply semi-micro method while people generally apply constant analysis in the quantitative chemical analysis. According to the relative amounts of the analyzed components contained in the sample, it is also roughly divided into constant component analysis (> 1%), minor component analysis (0.01 to 1%) and trace components analysis (<0.01%). For the analysis of some trace amount of components contained in some kinds of complicated mixture and some substances, it is necessary to perform separation and enrichment. This produces a series of separation techniques, such as extraction, distillation, ion exchange, chromatography, sedimentation and flotation separation, these chemical separation techniques are an integral part of the analysis.

Environmental Analytical Chemistry
Environmental Analytical Chemistry is briefly referred to environmental analysis. It is a kind of subject to study the types, components of pollutants in the environment as well as how to perform qualitative and quantitative analysis on the chemical contaminants in the environment. It is a branch of environmental chemistry.

Environmental analytical chemistry emerged, developed and improved during the process of solving environmental problems. In 1950s, the public nuisance disease occurred in Japan had alerted the whole world. In order to find the cause of public nuisance disease, after experiencing as long as 11 years, later, the chemists of environmental analysis had applied light spectrum and identified that the river in Itai-itai disease area contained harmful elements such as lead, cadmium, arsenic and so on. Further by means of tracking element analysis of the soil and food in the disease area, people had found high lead and cadmium content. Later, people had further conducted spectral quantitative analysis on the body and bone of the patients in the disease area and found that the bone ashes contained alarmingly high content of zinc, lead and cadmium. To determine the causative agent, people further incorporated zinc, lead and cadmium into the food for feeding animals and conduct trace elemental analysis for animals and confirmed the serious harm of cadmium on the bone, revealing the cause of the Itai-itai disease. The development of modern science, especially the development of modern chemistry, physics, mathematics, electronics, biology, as well as the emergence of accurate, reliable, sensitive, selective, rapid, simple environmental pollution analysis technology and automation equipment, has been resulting in the maturation of environmental analytical chemistry. Environmental analytical chemistry now has penetrated into all areas of the entire environmental science subject. It is the most effective means of access to environmental information quality.
The objects of the environmental analytical chemistry research are quite complicated, including air, water, soil, sediment, minerals, waste, animals, plants, food, and human tissue. The content of chemical elements or compound to be determined in the environmental analytic chemistry is very low, with the absolute content being within the level of 10-6 to 10-12 grams.


The analysis technology in the environmental analytical chemistry is developing towards the direction of continuous automation, computerization and joint combination of various methods and instruments. Currently applied automatic analysis methods include colorimetric analysis, ion selective electrode, x-ray fluorescence spectroscopy, atomic absorption spectroscopy, polarography, gas chromatography, liquid chromatography and flow injection analysis. Laser, as the light source of analytical chemistry technique, has also been applied. Since the laser analysis has properties of high resolution, high sensitivity, long-range and short-term, the laser technology will play a pivotal role in the development of environmental analytical chemistry.

With the deepened development of environmental science, environmental analytical chemistry is often demanded for trace levels and ultra-trace-level detection and analysis, therefore, high sensitivity. Thus study of analysis methods of high sensitivity, good selectivity, rapid trace and ultra trace will become the major development direction for environmental analysis in the near future.

Qualitative Analysis of Chemistry
Qualitative analytic chemistry is the subject to identify the chemical elements and atoms groups contained in the sample. It is a branch subject of the analysis chemistry. Its purpose is to ascertain the chemical composition of the research object (specimen).
The major research content of the qualitative analytic chemistry includes:

1 the tested samples were analyzed separately. Namely take part of the sample and use exclusive reaction to detect a desire detection component.
2 systematic analysis of the samples. This means successively apply a few selective reactions for gradual separation of the ions followed by separation of each group until separating to only one substance and finally apply confirming reaction to ascertain the existence of this substance. The most famous cation system analysis method is H2S system. In recent years, due to the use of advanced equipment, qualitative analysis has also rapidly developed together with multivariate analysis and has also become an important direction for analytical chemistry.

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Structure Chemical Name CAS MF
Valaciclovir iMpurity Valaciclovir iMpurity
Erlotinib hydrochloride Impurity C Erlotinib hydrochloride Impurity C
Linagliptin Impurity B Linagliptin Impurity B
Parecoxib Impurity A Parecoxib Impurity A
Parecoxib Impurity F Parecoxib Impurity F
2-(4-Benzhydrylpiperazino)ethyl acetoacetate 2-(4-Benzhydrylpiperazino)ethyl acetoacetate 89226-49-3 C23H28N2O3
Axitinib Impurity a Axitinib Impurity a 1347304-18-0 C22H18N4O2S
Cycloocta[b]pyridine, 4-(4-fluorophenyl)-5,6,7,8,9,10-hexahydro-2-(1-piperazinyl)- Cycloocta[b]pyridine, 4-(4-fluorophenyl)-5,6,7,8,9,10-hexahydro-2-(1-piperazinyl)- 132811-84-8 C21H26FN3
Linagliptin Impurity W Linagliptin Impurity W
(R)-4-fluoro-2-((3-methyl-2,4-dioxo-6-(piperidin-3-ylamino)-3,4-dihydropyrimidin-1(2H)-yl)methyl)benzonitrile (R)-4-fluoro-2-((3-methyl-2,4-dioxo-6-(piperidin-3-ylamino)-3,4-dihydropyrimidin-1(2H)-yl)methyl)benzonitrile C18H20FN5O2
1-cyclopropyl-6-fluoro-8-methoxy-7-((4aS,7aS)-octahydro-1H-pyrrolo[3,4-b]pyridin-1-yl)-4-oxo-1,4-dihydroquinoline-3-carboxylic acid 1-cyclopropyl-6-fluoro-8-methoxy-7-((4aS,7aS)-octahydro-1H-pyrrolo[3,4-b]pyridin-1-yl)-4-oxo-1,4-dihydroquinoline-3-carboxylic acid C21H24FN3O4
ethyl 1-cyclopropyl-7-fluoro-6,8-dimethoxy-4-oxo-1,4-dihydroquinoline-3-carboxylate ethyl 1-cyclopropyl-7-fluoro-6,8-dimethoxy-4-oxo-1,4-dihydroquinoline-3-carboxylate C17H18FNO5
Dapagliflozin Impurity 1 Dapagliflozin Impurity 1
Ibrutinib Impurity 5 Ibrutinib Impurity 5
Imatinib Impurity 4 Imatinib Impurity 4 942514-62-7 C30H33N7O
Macitentan Impurity 2 Macitentan Impurity 2 2211054-90-7 C10H8Br2N4O2
(R)-2-amino-4-(2-((4-(2-((2-hydroxy-2-phenylethyl)amino)ethyl) phenyl)amino)-2-oxoethyl)thiazole 3-oxide (R)-2-amino-4-(2-((4-(2-((2-hydroxy-2-phenylethyl)amino)ethyl) phenyl)amino)-2-oxoethyl)thiazole 3-oxide 1884646-38-1 C21H24N4O3S
Nilotinib Impurity 7 Nilotinib Impurity 7 2119583-26-3 C27H20F3N7O
Dehydro Benidipine Dehydro Benidipine 118935-44-7 C28H29N3O6
Etoposide Impurity B Etoposide Impurity B 100007-56-5 C29H32O13
Istradefylline Impurity 2 Istradefylline Impurity 2 606080-73-3 C20H24N4O4
Oxonic Acid Impurity 1 Oxonic Acid Impurity 1 60301-55-5 C3H3N3O2
Vortioxetine Impurity 4 Vortioxetine Impurity 4 1293489-77-6 C18H22N2S
Zidovudine USP Impurity G Zidovudine USP Impurity G 148665-49-0 C20H25N7O8
Quinoline, 6,7-dimethoxy-4-(4-nitrophenoxy)- Quinoline, 6,7-dimethoxy-4-(4-nitrophenoxy)- 190728-24-6 C17H14N2O5
Itopride Impurity A Itopride Impurity A 943518-63-6 C16H17NO4
Aripiprazole N1-Oxide Aripiprazole N1-Oxide
Aripiprazole N1-Oxide Aripiprazole N1-Oxide
1-METHYL-5-MERCAPTOTETRAZOLE, SODIUM SALT 1-METHYL-5-MERCAPTOTETRAZOLE, SODIUM SALT 51138-06-8 C2H3N4NaS
4-FORMYLCINNAMIC ACID 4-FORMYLCINNAMIC ACID 66885-68-5 C10H8O3
5-HYDROXY LANSOPRAZOLE 5-HYDROXY LANSOPRAZOLE 131926-98-2 C16H14F3N3O3S
ergosteryl 3-beta-D-glucoside ergosteryl 3-beta-D-glucoside 130155-33-8 C34H54O6
(3S,5R)-4-[5-([1,1'-Biphenyl]-4-ylmethyl)-3-methyl-2-oxopyrrolidin-1-yl]-4-oxobutanoic acid (3S,5R)-4-[5-([1,1'-Biphenyl]-4-ylmethyl)-3-methyl-2-oxopyrrolidin-1-yl]-4-oxobutanoic acid C22H23NO4
Ethyl (2R,4S)-4-([1,1'-biphenyl]-4-ylmethyl)-4-[4-(propan-2-yloxy)-4-oxobutanamido]-2-methylbutanoate Ethyl (2R,4S)-4-([1,1'-biphenyl]-4-ylmethyl)-4-[4-(propan-2-yloxy)-4-oxobutanamido]-2-methylbutanoate C27H35NO5
Regorafenib Impurity 1 Regorafenib Impurity 1
Regorafenib Impurity 6 Regorafenib Impurity 6 1187945-05-6 C20H12ClF4N3O4
Sofosbuvir Impurity 9 Sofosbuvir Impurity 9
Venlafaxine N-Oxide Impurity Venlafaxine N-Oxide Impurity 1021933-95-8 C16H25NO3
Vonoprazan Impurity 4 Vonoprazan Impurity 4
Vortioxetine Impurity 25 Vortioxetine Impurity 25 1639263-80-1 C18H22N2O2S
Cinacalcet Impurity B Cinacalcet Impurity B 66469-40-7 C19H19N
Dapagliflozin Impurity D Dapagliflozin Impurity D 2133407-75-5 C21H25ClO6
Escitalopram Impurity Escitalopram Impurity 91283-87-3 C18H14FNO3
Furosemide Imp.(EP) Furosemide Imp.(EP)
Nifuratel Impurity Nifuratel Impurity 167103-07-3 C6H5N3O4
Vinpocetine Impurity Vinpocetine Impurity 102341-40-2 C19H23N3O
2-amino-9-((1R,3S,4S)-4-hydroxy-3-(hydroxymethyl)-2-methylenecyclopentyl)-1,9-dihydro-6H-purin-6-one 2-amino-9-((1R,3S,4S)-4-hydroxy-3-(hydroxymethyl)-2-methylenecyclopentyl)-1,9-dihydro-6H-purin-6-one 1367369-81-0 C12H15N5O3
N-(3,4-dichlorophenyl)-7-methoxy-6-(3-morpholinopropoxy)quinazolin-4-amine N-(3,4-dichlorophenyl)-7-methoxy-6-(3-morpholinopropoxy)quinazolin-4-amine 2089650-13-3 C22H24Cl2N4O3
Moxifloxacin Impurity 8 Moxifloxacin Impurity 8
(3R,5S)-7-(2-(4-fluorophenyl)-5-isopropyl-3-phenyl-4-(phenylcarbamoyl)-1H-pyrrol-1-yl)-3,5-dihydroxyheptanoic acid (3R,5S)-7-(2-(4-fluorophenyl)-5-isopropyl-3-phenyl-4-(phenylcarbamoyl)-1H-pyrrol-1-yl)-3,5-dihydroxyheptanoic acid C33H35FN2O5
Olaparib Imp.2 Olaparib Imp.2
Ciprofloxacin impurity I Ciprofloxacin impurity I C17H18FN3O3
5-(4'-((2-butyl-4-chloro-5-(isopropoxymethyl)-1H-imidazol-1-yl)methyl)-[1,1'-biphenyl]-2-yl)-1H-tetrazole 5-(4'-((2-butyl-4-chloro-5-(isopropoxymethyl)-1H-imidazol-1-yl)methyl)-[1,1'-biphenyl]-2-yl)-1H-tetrazole 1332713-64-0 C25H29ClN6O
2-(((3aS,4R,6S,6aR)-6-((5-amino-6-chloro-2-(propylthio)pyrimidin-4-yl)amino)-2,2-dimethyltetrahydro-4H-cyclopenta[d][1,3]dioxol-4-yl)oxy)ethan-1-ol 2-(((3aS,4R,6S,6aR)-6-((5-amino-6-chloro-2-(propylthio)pyrimidin-4-yl)amino)-2,2-dimethyltetrahydro-4H-cyclopenta[d][1,3]dioxol-4-yl)oxy)ethan-1-ol C17H27ClN4O4S
1,2-bis(bromomethyl)-4,5-dimethoxybenzene 1,2-bis(bromomethyl)-4,5-dimethoxybenzene 26726-81-8 C10H12Br2O2
Alvimopan Impurity 2 Alvimopan Impurity 2
Alvimopan Impurity 4 Alvimopan Impurity 4
Isavuconazole Impurity 13 Isavuconazole Impurity 13
Sofosbuvir Impurity13 Sofosbuvir Impurity13 220503-64-0 C38H31N3O9
21-Acetyl-6β-fluorotriamcinolone Acetonide 21-Acetyl-6β-fluorotriamcinolone Acetonide 67438-37-3 C26H32F2O7
Quetiapine EP Impurity W Quetiapine EP Impurity W 1800608-95-0 C34H32N4O2S2
(2R,3R)-1,1,4,4-tetraphenylbutane-1,2,3,4-tetrol (2R,3R)-1,1,4,4-tetraphenylbutane-1,2,3,4-tetrol 117780-08-2 C28H26O4
(11β,16α)-21-(Acetyloxy)-11,16,17-trihydroxypregna-1,4,14-triene-3,20-dione (11β,16α)-21-(Acetyloxy)-11,16,17-trihydroxypregna-1,4,14-triene-3,20-dione 131918-72-4 C23H28O7
(S)-Alogliptin Benzoate Salt (S)-Alogliptin Benzoate Salt 1638544-64-5 C25H27N5O4
(S)-Alogliptin Benzoate Salt (S)-Alogliptin Benzoate Salt 1638544-64-5 C25H27N5O4
O-Acetyl Silodosin O-Acetyl Silodosin 160970-86-5 C27H34F3N3O5
Azilsartan Impurity Azilsartan Impurity 1675221-59-6 C25H22N2O5
Agomelatine Impurity 1 Agomelatine Impurity 1
Agomelatine Impurity 1 Agomelatine Impurity 1
Olaparib Impurity I Olaparib Impurity I
Brexpiprazole Impurity C Brexpiprazole Impurity C
Dapoxetine Impurity 7 Dapoxetine Impurity 7
Irbesartan Impurity 5 Irbesartan Impurity 5 1213252-81-3 C25H28N6O
Cabozantinib impurity C Cabozantinib impurity C
Loratadine Impurity 4 Loratadine Impurity 4 C22H23ClN2O2
Metoprolol IMpurity 4 Metoprolol IMpurity 4 C15H25NO3
Clindamycin  impurity Clindamycin impurity 198080-64-7 C18H32N2O5S
Digoxin impurity Digoxin impurity
Lamivudine impurity Lamivudine impurity
Levothyroxine Sodium  impurity Levothyroxine Sodium impurity 27566-09-2 C14H21NO4
Dexchlorpheniramine impurity Dexchlorpheniramine impurity 73775-50-5 C12H15ClN2
(S)-N-(2-(1-(3-ethoxy-4-hydroxyphenyl)-2-(methylsulfonyl)ethyl)-1,3-dioxoisoindolin-4-yl)acetamide (S)-N-(2-(1-(3-ethoxy-4-hydroxyphenyl)-2-(methylsulfonyl)ethyl)-1,3-dioxoisoindolin-4-yl)acetamide 1384441-38-6 C21H22N2O7S
(1R,2S,3S)-Aprepitant (1R,2S,3S)-Aprepitant 172822-28-5 C23H21F7N4O3
(((4-methoxy-3,5-dimethylpyridin-2-yl)methyl)sulfinyl)-1H-benzo[d]imidazole compound with 6-methoxy-1-((4-methoxy-3,5-dimethylpyridin-2-yl)methyl)-2-(((4-methoxy-3,5-dimethylpyridin-2-yl)methyl)sulfinyl)-1H-benzo[d]imidazole (1:1) (((4-methoxy-3,5-dimethylpyridin-2-yl)methyl)sulfinyl)-1H-benzo[d]imidazole compound with 6-methoxy-1-((4-methoxy-3,5-dimethylpyridin-2-yl)methyl)-2-(((4-methoxy-3,5-dimethylpyridin-2-yl)methyl)sulfinyl)-1H-benzo[d]imidazole (1:1)
6-benzyloxy-8-((R)-2-chloro-1-hydroxy-ethyl)-4H-benzo[1,4]-oxazin-3-one 6-benzyloxy-8-((R)-2-chloro-1-hydroxy-ethyl)-4H-benzo[1,4]-oxazin-3-one 869478-11-5 C17H16ClNO4
ethyl (41R,13aS)-13a-ethyl-2,3,41,5,6,13a-hexahydro-1H-indolo[3,2,1-de]pyrido[3,2,1-ij][1,5]naphthyridine-12-carboxylate ethyl (41R,13aS)-13a-ethyl-2,3,41,5,6,13a-hexahydro-1H-indolo[3,2,1-de]pyrido[3,2,1-ij][1,5]naphthyridine-12-carboxylate 77549-94-1 C22H26N2O2
Dolutegravir Impurity 2 Dolutegravir Impurity 2
Lesinurad Impurity J Lesinurad Impurity J 1210330-64-5 C14H10BrN3O2S
Neratinib Impurity 4 Neratinib Impurity 4 1144516-18-6 C31H32ClN6O3+
Avibactam Impurity 3(2R,5S) Avibactam Impurity 3(2R,5S) 1383814-68-3 C7H12N3NaO6S
Linagliptin Impurity C Linagliptin Impurity C 1791405-13-4 C15H20N6O2
1,1-Cyclopropanedicarboxamide,N-[4-[(6,7-dimethoxy-4-quinolinyl)oxy]phenyl]-N'-phenyl- 1,1-Cyclopropanedicarboxamide,N-[4-[(6,7-dimethoxy-4-quinolinyl)oxy]phenyl]-N'-phenyl- 849221-94-9 C28H25N3O5
methyl (41S,12S,13aS)-13a-ethyl-12-hydroxy-8-methoxy-2,3,41,5,6,12,13,13a-octahydro-1H-indolo[3,2,1-de]pyrido[3,2,1-ij][1,5]naphthyridine-12-carboxylate methyl (41S,12S,13aS)-13a-ethyl-12-hydroxy-8-methoxy-2,3,41,5,6,12,13,13a-octahydro-1H-indolo[3,2,1-de]pyrido[3,2,1-ij][1,5]naphthyridine-12-carboxylate 57430-34-9 C22H28N2O4
(R)-1-[3-[4-Amino-3-(4-phenoxyphenyl)-1H-pyrazolo[3,4-d]pyrimidin-1-yl]piperidin-1-yl]ethanone (R)-1-[3-[4-Amino-3-(4-phenoxyphenyl)-1H-pyrazolo[3,4-d]pyrimidin-1-yl]piperidin-1-yl]ethanone 1288338-95-3 C24H24N6O2
Amlodipine Impurity 17 Amlodipine Impurity 17 C26H31ClN2O8S
Edoxaban Impurity 12 (1R,2R,4S) Edoxaban Impurity 12 (1R,2R,4S)
Rivaroxaban Impurity 26 Rivaroxaban Impurity 26 1838133-00-8 C23H21Cl2N3O5S2
Erlotinib Erlotinib 938185-06-9 C16H11N3O2
methyl (41R,12S,13aS)-13a-ethyl-12-hydroxy-2,3,41,5,6,12,13,13a-octahydro-1H-indolo[3,2,1-de]pyrido[3,2,1-ij][1,5]naphthyridine-12-carboxylate methyl (41R,12S,13aS)-13a-ethyl-12-hydroxy-2,3,41,5,6,12,13,13a-octahydro-1H-indolo[3,2,1-de]pyrido[3,2,1-ij][1,5]naphthyridine-12-carboxylate 18374-18-0 C21H26N2O3
Brexpiprazole sulfoxide impurity Brexpiprazole sulfoxide impurity 1191900-51-2 C25H27N3O3S
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