3 results about "Precolumn derivatization" patented technology

The application discloses an analysis method of tobramycin sulfate injection and application thereof, and the analysis method comprises the following steps: performing a pre-column derivatization reaction on a sample containing tobramycin and impurities by using a derivatization reagent, and then performing high performance liquid chromatography analysis on the sample after derivatization. The analysis is performed by gradient elution of a mobile phase A and a mobile phase B composed of water, acetonitrile and phosphoric acid, wherein the content of acetonitrile in the mobile phase B is higher than that in the mobile phase A, and effective separation of tobramycin and related impurities is realized by multi-stage gradient elution. The method can simultaneously separate and detect process impurities, degradation impurities and unknown impurities, has good separation degree and stability indicating capacity, and is suitable for quality control and drug stability research of tobramycin sulfate injection.

The invention discloses a method for detecting the content of chloroacetaldehyde in dimethylaminoacetaldehyde diethyl acetal, which comprises the following steps: carrying out precolumn derivatization on chloroacetaldehyde by using a derivatization reagent, and carrying out isocratic or gradient elution by using a reversed-phase high-performance liquid chromatography and an acetonitrile-phosphoric acid aqueous solution as a mobile phase. The method realizes accurate quantification of chloroacetaldehyde in dimethylaminoacetaldehyde diethyl acetal, is high in detection speed, low in cost and simple to operate, has good specificity, sensitivity, precision and accuracy, is an effective quality control method for dimethylaminoacetaldehyde diethyl acetal, and has wide application prospects. And the product quality of afatinib maleate bulk drugs and related preparations synthesized by using dimethylaminoacetaldehyde diethyl acetal as a starting material is further ensured.

The invention relates to the technical field of chemical detection, in particular to a method for determining the content of 3-(dimethyl carbamoyl) pyridine-2-sulfonyl chloride through a pre-column derivatization method, which is characterized in that corresponding 3-(dimethyl carbamoyl) pyridine-2-sulfonic acid methyl ester can be effectively generated through the reaction of a derivatization agent methanol and 3-(dimethyl carbamoyl) pyridine-2-sulfonyl chloride, and the content of 3-(dimethyl carbamoyl) pyridine-2-sulfonyl chloride can be measured through the pre-column derivatization method. The method comprises the following steps: taking a sample solution to be detected as a mobile phase to avoid decomposition in the mobile phase to generate 3-(dimethylaminoformyl) pyridine-2-sulfonic acid, then carrying out high performance liquid chromatography analysis on the sample solution and a standard sample solution, taking a mixture of methanol and a phosphoric acid aqueous solution as the mobile phase, and comparing with a standard sample to calculate the content of 3-(dimethylaminoformyl) pyridine-2-sulfonyl chloride in the sample to be detected. The method provided by the invention has the advantages of strong specificity and good precision, is especially suitable for quality evaluation and control of organic synthesis intermediates, and has important effect and practical significance for ensuring the quality of final products.