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 liquid chromatograph detection, in particular to a method for separating and measuring acitretin and its impurities. In the method, the stationary phase is an octadecylsilane-bonded silica gel chromatographic column, and a mobile phase consisting of a mobile phase A and a mobile phase B is used for elution and separation; the mobile phase A is a 0.2-1% glacial acetic acid aqueous solution, and the mobile phase A is Mobile phase B is an organic solvent. The method can completely separate and detect Acitretin and its eight impurities within 60 minutes, with high accuracy and good sensitivity.

The invention discloses a method for measuring related substances in succinic acid Trelagliptin raw materials and relates to the field of analytic chemistry. According to the method, high performance liquid chromatography is adopted, a sample solution is injected into a high performance liquid chromatograph, and the related substances in the succinic acid Trelagliptin raw materials are measured; according to chromatographic conditions, a 100-5C18 chromatographic column of the Kromasil company is adopted as a chromatographic column, a flowing phase A and a flowing phase B are both a mixed solution of an acid aqueous solution and an organic solvent, the sum of the volume percentage of the flowing phase A and the volume percentage of the flowing phase B is kept 100% all the time, and linear gradient elution is performed. According to the method, the 100-5C18 chromatographic column of the Kromasil company is adopted, the gradient elution program of the flowing phases is optimized, and the related substances in the succinic acid Trelagliptin raw materials can be effectively separated. The method solves the separation and measurement problem of the related substances in the succinic acid Trelagliptin raw materials, and therefore it is guaranteed that the mass of the succinic acid Trelagliptin raw materials is controllable.

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 belongs to the field of analytical chemistry and relates to a method for separating and determining a linezolid raw material (S)-1-acetamido-2-acetoxyl-3-chloropropane X3 and its process impurities X2, in particular to a method for separating and determining a linezolid raw material X3 and its process impurities X2 by adopting a high performance liquid chromatography. A chromatographic column adopted in the method uses octadecyl silane bonded silica gel as a filler, water added with an ion-pairing agent and acetonitrile which are in certain proportion are adopted as mobile phases. The method can completely separate the linezolid raw material (S)-1-acetamido-2-acetoxyl-3-chloropropane X3 and the its process impurities X2, is simple, convenient, feasible, good in reproducibility and strong in specificity and can effectively determine the related substance content in the linezolid raw material (S)-1-acetamido-2-acetoxyl-3-chloropropane X3.

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