43results about How to "Solving Separation Assay Problems" patented technology

The invention provides a method for determining related substances in Trelagliptin tablets, and relates to the field of analytical chemistry. The method comprises the steps that a high-performance liquid chromatography method is adopted, a sample solution is injected into a high-performance liquid chromatographic instrument, determination of the related substances in the Trelagliptin tablets is completed, and the chromatographic conditions are that a chromatographic column takes silica gel of which the surface is provided with electric hybrid particles as a filler, a mobile phase A is an acidic aqueous solution, a mobile phase B is an organic solvent, the sum of the volume percent of the mobile phase A and the volume percent of the mobile phase B maintains 100% all the time, and linear gradient elution is conducted. According to the method for determining the related substances in the Trelagliptin tablets, an Xselect C18 chromatographic column is adopted, optimization is conducted on the mobile phase gradient elution program, and the related substances in the Trelagliptin tablets can be effectively separated. The separation determination problem of the related substances in the Trelagliptin tablets is solved, and therefore it is guaranteed that the quality of the Trelagliptin tablets is controllable.

The invention belongs to the field of analytical chemistry, and specifically relates to a method for separating and measuring related impurities in acrivastine and a preparation thereof. According tothe method, octadecyl silane bonded silica gel is adopted as a solid phase, and a mobile phase consisting of aqueous solutions of acetonitrile, tetrahydrofuran and triethylamine is adopted for elutionfor solid-liquid separation; the related impurities include one or more of a double oxidation impurity I, a single oxidation impurity II, Z-type III, E-type IV and E-isomer V. According to the methodprovided by the invention, the related impurities in the acrivastine and the preparation thereof are separated and detected by high performance liquid chromatography, and can be totally separated anddetected within 18 minutes; the method has the advantages of high separation degree, strong specificity, high sensitivity, easiness in operation, simpleness and quickness, so as to guarantee that thequality of the acrivastine and the preparation thereof is controllable, and finally determines the safety and effectiveness of a product, and is of great significance to quality control on the acrivastine.

The invention belongs to the field of analytical chemistry, and discloses a method for separately testing a levocetirizine hydrochloride intermediate and related substances of the levocetirizine hydrochloride intermediate by liquid chromatography. The method comprises the following steps: a chromatographic column taking octadecylsilane chemically bonded silica as a filler uses a certain proportion of buffer salt solution-organic phase as a mobile phase to quantificationally test the content of the levocetirizine hydrochloride intermediate and the content of the related substances of levocetirizine hydrochloride intermediate, so that the quality of the levocetirizine hydrochloride intermediate is effectively controlled, and the controllable quality of levocetirizine hydrochloride is ensured. The method is high in specificity and accuracy, and simple and convenient to operate.

The invention belongs to the field of analytical chemistry, discloses a method for separation and determination of vortioxetine hydrobromide intermediate 1-bromo-2-iodo-benzene related substances by liquid chromatography. The method takes a chromatographic column with octadecylsilane bonded silica gel as a packing, takes a certain ratio of water-organic phase as a mobile phase, and can be used for quantitative determination of the contents of a vortioxetine hydrobromide intermediate and the related substances thereof, so as to effectively control the quality of the vortioxetine hydrobromide intermediate and ensure controllable quality of a vinpocetine hydrobromide final product. The method has the advantages of strong specificity, high accuracy and convenience in operation.

The invention belongs to the field of analytical chemistry, relates to a method for the simultaneous determination of palonosetron hydrochloride and four impurities. In particular, a high performance liquid chromatography method is employed for the simultaneous separation and determination of palonosetron hydrochloride and four process impurities A-D (including a degradation product). The column used in the method employs octadecyl silane bonded silica gel as a filler, and the method employs an inorganic salt buffer system supplemented with a certain proportion of an ion pair reagent and an organic solvent as the mobile phases for gradient elution. The method can simultaneously fully separate the process impurities and degradation products of palonosetron hydrochloride, has the advanategs of simpleness, feasibility, good reproducibility and strong specificity, and can effectively determinw palonosetron hydrochloride bulk drugs and medicine and the content of the relevant materials in the preparation.

The invention belongs to the field of analytical chemistry and discloses a method for separating and detecting lurasidone hydrochloride intermediate 3-(1-piperazinyl)-1,2-benzisothiazole and related substances through liquid chromatography. According to the method, octyl silane bonded silica gel serves as a chromatographic column of filler, ion-pairing reagent-buffer salt solution-organic phase in a certain proportion serves as a mobile phase, and the content of the lurasidone hydrochloride intermediate and the related substances of the intermediate can be measured, so that purity of reactants in the production process of lurasidone hydrochloride is effectively controlled, side reactions and impurities are reduced, the yield of the product is increased, and the quality of the product is improved. The method is high in specificity, high in accuracy and easy and convenient to operate.

The invention discloses a pharmaceutical analysis method for efficiently determining gangliosides GM1 and impurities thereof, and belongs to the technical field of pharmaceutical analysis. According to the method, a chromatographic column taking octadecylsilane chemically bonded silica as a filler is used as a stationary phase, and a mixed solution of a buffer salt solution and an organic phase isused as a mobile phase, so that the gangliosides GM1 related substances and content can be effectively separated and determined.

The invention belongs to the field of analytical chemistry and discloses a method for separating and determining etoricoxib and related substances thereof by using liquid chromatography. The method can be used for quantitatively determining the contents of etoricoxib and related substances thereof by using phenyl silane bonded silica gel as a chromatographic column of fillers and using a certain proportion of buffer salt solutions-organic phases as mobile phases, thus effectively controlling the quality of etoricoxib. The method has strong specificity and high precision and is simple and convenient to operate.

The invention relates to a method for separating and measuring the impurity-diglycol acid (natrium) (DGA) in carboxymethyl chitosan by a liquid chromatography method. A high-efficiency liquid chromatography method for separating and measuring the impurity DGA in carboxymethyl chitosan products adopts a chromatographic column taking C18 as stuffing, takes mixed solutions prepared by buffer salts with the PH value being 1.5-3.5 and organic phases according to a certain mixture ratio as a flowing phase, and performs detection and quantization by an ultraviolet detector. The method can effectively separate and measure the impurity DGA in the carboxymethyl chitosan and solves the problem of separation and measurement of the impurity DGA in the carboxymethyl chitosan, thereby ensuring the controllable quality of the carboxymethyl chitosan.

The invention discloses a method for measuring nebivolol hydrochloride impurities by a liquid phase chromatography method. Cellulose three(3, 5-dimethylphenyl amino formate is taken as a chiral chromatographic column of a filling material, and a mixed solution of a buffer salt solution and an organic phase according to certain ratio is taken as a mobile phase. The method can rapidly and accurately separate and measure the two optical isomers.

The invention belongs to the field of analytical chemistry. The invention discloses a method for rapidly separating and detecting the optical purity of a brivaracetam starting material (R)-4-propyl-dihydrofuran-2-one by using gas chromatography. According to the method, a cyclodextrin chiral capillary chromatographic column and a hydrogen flame ionization detector are adopted, so that the opticalpurity and the isomer content of the brivaracetam starting material can be quantitatively determined, and the stability of the optical isomer of the brivaracetam starting material is indicated. The method disclosed by the invention is strong in specificity, high in accuracy, good in durability and simple and rapid to operate.

The invention relates to the technical field of pharmaceutical analysis, in particular to a method for analyzing ethyl gatetanecarboxylate and related impurities by using high performance liquid chromatography. A chromatographic column adopted by the method takes octadecyl bonded silica gel as a filling agent, a buffer salt solution and an organic solvent are adopted for gradient elution, the flow velocity is 0.9-1.1 ml/min, and the column temperature is 18-22 DEG C; the detection wavelength is 220 nm or 250 nm; the method can effectively separate and accurately quantify seven known impurities possibly existing in the starting material ethyl gatetanecarboxylate of moxifloxacin hydrochloride within 42 minutes, the separation effect of the other two known impurities possibly existing in the starting material and the seven known impurities is good, and the method has no interference on impurity identification and quantitative detection. The problem of separation and determination of known impurities in ethyl gatetanecarboxylate, which cannot be solved in the prior art, is provided; the analysis method is high in sensitivity; the specificity is high; the reproducibility is good; the operation is simple and feasible.

The invention belongs to the field of analytical chemistry, and discloses a method for separating and determining a compound A[(2RS)-1-ethyl pyrrolidinone-2-yl-methylamine] and imidazole in an amisulpride final product {4-amino-N-[[(2RS)1-ethyl pyrrolidinone-2-yl] methyl]-5-(ethyl sulfonyl)-2-methoxybenzamide} by using a gas chromatographic method. According to the method, a capillary chromatographic column filled with polyethylene glycol and a hydrogen flame ionization detector are adopted, and the content of impurities A[(2RS)-1-ethyl pyrrolidone-2-yl-methylamine] and imidazole in a final product of amisulpride can be quantitatively determined, so that the purity of reactants in the process of synthesizing amisulpride is effectively controlled, side reactions and impurities are reduced, and the product yield is improved. The method is high in specificity, high in accuracy and simple and convenient to operate.