31 results about "Impurity profiling" patented technology

The invention provides an impurity analysis and preparation method for clindamycin phosphate, which is used for analyzing a clindamycin phosphate raw material and separating and preparing impurities from the clindamycin phosphate raw material. The method comprises the following steps of: measuring the clindamycin phosphate raw material by using liquid chromatography-mass spectrometry (LC-MS), and determining one or more impurities in the raw material according to the relative retention time and / or molecular weight of each analyzed component; and determining the conditions of preparative chromatography according to chromatographic retention behaviors displayed by the relative retention time of each impurity, and collecting the one or more impurities corresponding to the relative retention time and / or molecular weights by using the preparative chromatography.

The invention relates to detection equipment and technology for a gas chromatography instrument, in particular to a gas chromatography detection system and method for analyzing trace impurities in ultrahigh pure gas. A first molecular sieve chromatographic column (51) is arranged between a switching valve VI (1) and a switching valve VII (2); a second molecular sieve chromatographic column (52) is arranged between a switching valve VII (2) and a switching valve VIV (4); and a second column separator (62) is arranged between the switching valve VIII (3) and switching valve VIV (4). A secondary sampling way is adopted for sample gas, and a main component is pre-cut during primary sample feeding of a ten-way switching valve VI (1) and subjected to back flushing during secondary sample feeding of the ten-way switching valve VI (1); and the main component is separated and switched, and enters a helium ion detector (8) for analyzing. The gas chromatography detecting system is controlled through each valve, the sequence of actions is executed by using an event draw-up program, the entire analyzing process is controlled automatically, actions are rapid, consistent and reliable, and the data repeatability and accuracy of the system are ensured through a stable flow gas channel and accurate valve switching.

The invention provides an impurity analysis preparation method for clindamycin. The method is used for analyzing clindamycin materials and separating and preparing impurities from the materials, and comprises the following steps of: (a) measuring the clindamycin materials by an LC-MS (Liquid Chromatography-Mass Spectrometry) method, and determining one or more impurities in the materials according to the relative retention time and / or the molecular weight of the analyzed component; (b) determining the conditions of a column chromatography method according to the relative retention time and / or the molecular weight of one or more impurities, and gathering one or more impurities corresponding to the relative retention time and / or the molecular weight by the normal phase silica gel column chromatography method; and (c) determining the conditions of a preparative chromatography method according to the chromatographic retention behavior displayed by the relative retention time of one or more impurities in the step (a), and collecting one or more impurities corresponding to the retention time by the preparative chromatography method.

The invention relates to a 5,6,4'-trihydroxyl flavone-7-O-D-glucuronic acid related substance b which is successfully prepared through selective elimination and hydrolysis by taking 5,6,4'-triacetoxy flavone-7-O-D-triacetyl methyl glucuronate (the structural formula is as shown in a formula II) as a raw material. The related substance b is further purified, and finally, a 5,6,4'-trihydroxyl flavone-7-O-D-glucuronic acid related substance b monomer is obtained to obtain a related substance chemical structure after confirmation. The method is short in synthetic route, low in cost, simple to operate, accurate in result, high in product purity, high in reaction yield and easy for product purification, and can be used for impurity analysis and control of a synthesized 5,6,4'-trihydroxyl flavone-7-O-D-glucuronic acid sample, so that quality control of the synthesized 5,6,4'-trihydroxyl flavone-7-O-D-glucuronic acid is facilitated, and the product quality is better guaranteed.

The invention relates to an impurity analysis method for multiple vitamin preparations. The method comprises the following steps of preparing a test solution of the vitamin preparations; dissolving o-phthalaldehyde and 2-mercaptoethanol based on a mass ratio of 1 to (2-5) in methanol, adding a boric acid buffer solution, and adjusting the pH value to 3-5 to obtain a derivatization reagent; and taking the test solution, adding the derivatization reagent to carry out online derivatization reaction, and injecting the derivatized test solution into a high performance liquid chromatograph, therebydetecting impurities in the test solution. According to the method, folic acid impurity A, folic acid impurity D, p-aminobenzoic acid and 3-aminopropanol in the vitamin preparations can be effectivelydetected; and the method is high in sensitivity and good in specificity.

The invention relates to the field of high-purity gas impurity detection and specifically relates to a method for increasing detection sensitivity of special impurities in high-purity hydrogen chloride. According to the method for increasing detection sensitivity of special impurities in high-purity hydrogen chloride disclosed by the invention, two parallel chromatographic columns are used; an independent temperature-control column box is adopted, so that column temperatures of the two parallel chromatographic columns can be guaranteed, and such an arrangement is beneficial to respectively separated components; a helium ion detector is used for detecting trace impurities and the limit of detection can be reduced to 1-10ppb; a filler special for high-purity hydrogen chloride chromatographicanalysis and nanometer titanium dioxide are adopted for modifying a capillary column, so that the separation of trace impurities in electronic hydrogen chloride can be boosted; the helium ion detector is used for detecting hydrogen chloride according to the method, so that the sensitivity is high and the limit of detection is low; impurity component response is linear; after a gas flow is designed, sample can be injected at one time and the requirements for analyzing all the impurities of electronic hydrogen chloride gas can be met.

The invention discloses an impurity HPLC analysis method for nedaplatin. In the method, octadecylsilane bonded silica gel is used as a filler (recommendation: AQ-C18), the detection wavelength is 205-222nm, and the column temperature is 20~45℃, the mobile phase is a mixture of pH6.0~8.5 buffer and polar organic solvent, characterized in that the mobile phase is to elute the impurities in the nedaplatin sample by gradient elution, pH6. The initial ratio of 0-8.5 buffer solution to polar organic solvent is 100:0-90:10, and the final ratio is 90:10-60:40; the flow rate of mobile phase is 0.5-1.0ml / min; prepared with mobile phase into a solution containing 0.5 mg to 2 mg / ml of nedaplatin; inject 5 μl to 20 μl of the sample solution into a high performance liquid chromatograph, record the chromatogram and perform sample analysis. After using the HPLC analysis method of the present invention, the theoretical plate number of the main peak of the product is obviously increased, and more impurities can be separated, so that the accuracy of analyzing the nedaplatin sample is improved.

The invention discloses a device for analyzing impurities in hydrogen isotope gas, which comprises a carrier gas source, a standard gas source, a sample container, a chromatographic column box, a hydrogen purifier and a thermal conductivity detector, the chromatographic column box comprises a first chromatographic column and a second chromatographic column, and the hydrogen purifier can adsorb the hydrogen isotope gas. According to the invention, the hydrogen purifier is connected in series in front of the first chromatographic column, and the hydrogen purifier can adsorb hydrogen isotope gas below the detection limit of the thermal conductivity detector so as to eliminate the overlap between deuterium and tritium peaks and helium peaks, so that the analysis precision of helium impurities in the hydrogen isotope gas is improved; the invention further provides a method for analyzing the impurities in the hydrogen isotope gas, argon is used as carrier gas, analysis is carried out through the second chromatographic column, and therefore interference of argon impurities in a hydrogen isotope sample on analysis of oxygen impurities is avoided. According to the invention, high-precision analysis of impurities such as nitrogen, methane and carbon monoxide is realized while high-precision analysis of impurities such as helium and oxygen in the hydrogen isotope gas is realized.

The present invention provides a method for analyzing impurities of an oligonucleotide sequence based on high-throughput sequencing. The method of the present invention comprises the following steps: constructing a high-throughput sequencing library for analysis of impurities of an oligonucleotide sequence; subjecting the high-throughput sequencing library to high-throughput sequencing, and analyzing the nucleotide sequence components according to the sequencing results; the sequence of the extension primer used in the construction of the high-throughput sequencing library consisting of the DNA molecule set forth in positions 1-22 of SEQ ID NO: 2 and N bases (A, T, C or G) in sequence; and N being an integer greater than or equal to 6. It is proved by experiments that the method for analyzing impurities of an oligonucleotide sequence based on high-throughput sequencing of the present invention can quickly, accurately, and comprehensively analyze the purity and content of each component in the oligonucleotide sequence.

The invention discloses an ultra-high performance liquid chromatography analysis method for clozapine, which uses Waters UPLC AcQuity H-Class, adopts Agilent Rapid Resolution HD column, and uses methanol-potassium dihydrogen phosphate-water as mobile phase to carry out gradient elution. This method can simultaneously analyze all known impurities in clozapine raw materials and their preparations, and can effectively control the content of known impurities through the main component self-contrast method with correction factor, the main peak and adjacent impurity peaks and the difference between each impurity peak. The degree of separation was greater than 1.5. The method is simple, time-consuming and accurate in impurity analysis, providing a reliable analytical method for clozapine.

The invention belongs to the field of synthesis of medicines, and specifically relates to a preparation method for a sarpogrelate hydrochloride photodegradable impurity III. The sarpogrelate hydrochloride photodegradable impurity III is prepared by comprising five-step reactions of substitution reaction, addition reaction, esterification reaction, epoxidation reaction and reduction reaction with 2-[2-(3-methoxyphenyl)vinyl]phenol as a raw material; and after column chromatography separation of a crude sarpogrelate hydrochloride photodegradable impurity III, purity reaches more than 99%. The preparation method provided by the invention has simple operation and mild reaction; the sarpogrelate hydrochloride photodegradable impurity III has high purity and can be applied in analysis of impurity profiling; and total yield is high.

The invention discloses an ultra-high performance liquid chromatography analysis method for dihydralazine sulfate and its related substances. Waters UPLC AcQuity H-Class is used, a reversed-phase C18 column is used, and potassium dihydrogen phosphate-phosphate buffer is used as the mobile phase A, Gradient elution with methanol as mobile phase B. The method can effectively control the known impurity content through the principal component self-contrast method with a correction factor, and the separation between the main peak and adjacent impurity peaks and between each impurity peak is greater than 1.5. The method of the application is simple, easy to operate, and has good reproducibility, accurate analysis and positioning of impurities, and can provide a reliable analysis method for controlling the quality of dihydralazine sulfate and its tablets.