196 results about "Isocratic elution" patented technology

The invention relates to the technical field of drug analysis and detection, and particularly discloses a method for detecting the residual quantity of glucose in an irinotecan hydrochloride liposome injection. According to the method, irinotecan hydrochloride in the liposome is fully separated from small molecular substances such as glucose and sodium chloride by adopting an ultrafiltration method, then, a Waters XBridge BEH HILIC chromatographic column is adopted, a mixed solution of an acetate buffer solution with the pH value of 3.8-4.2 and acetonitrile is used as a mobile phase, and the content of irinotecan hydrochloride in the liposome is detected in an isocratic elution mode by adopting a high performance liquid chromatography method. The effective separation of glucose, sodium chloride, 4-hydroxyethylpiperazine, sucrose octasulfate potassium and other substances is realized, and the condition of the glucose residue in the irinotecan hydrochloride liposome is accurately detected. The invention provides a reliable guarantee for improving and better controlling the quality of the irinotecan hydrochloride liposome injection product, and has very important significance for improving the medication safety.

The invention relates to the technical field of food safety detection, in particular to a method for detecting urea in bean sprouts and application thereof.The method comprises the following steps that smashed bean sprouts are subjected to two times of ultrasonic extraction and centrifugation, supernate is combined, and an extracting solution is obtained; fixing the volume and filtering to obtain a to-be-detected solution; detecting the liquid to be detected by using liquid chromatography-tandem mass spectrometry; an extraction solvent for ultrasonic extraction is a 5% formic acid-acetonitrile composite solution; the conditions of the liquid chromatography-tandem mass spectrometry are as follows: the chromatographic conditions are as follows: a chromatographic column is an HILIC column; the sample size is 10 [mu] L; a mobile phase is a mixed solution of a 0.02 mmol / L ammonium acetate buffer salt solution and acetonitrile, and isocratic elution is carried out; the flow rate is 0.3 mL / min; the column temperature is 40 DEG C; mass spectrum conditions are as follows: an electrospray ionization (ESI) positive ion mode, electrospray voltage of 4000 V, sheath gas pressure of 30 psi, auxiliary gas pressure of 5 psi, capillary heating temperature of 300 DEG C and scanning mode of MRM. The method disclosed by the invention is free from substance interference, high in sensitivity, accurate in result, low in cost and high in efficiency, and can be used as a standard detection method.

The invention discloses a method for determining bedaquiline fumarate clean verification target residues, and relates to the technical field of instrument analysis of chemical pharmacy. The method comprises the following steps: preparing a sample wiping solution; determining the content of bedaquiline fumarate in the sample wiping solution by adopting a liquid chromatography; chromatographic conditions are as follows: a chromatographic column is a VP-ODS C18 column; mobile phases: a potassium hexafluorophosphate aqueous solution and acetonitrile, wherein the concentration of the potassium hexafluorophosphate aqueous solution is 0.01-0.03 mol / L; the elution mode is isocratic elution; the flow rate is 1 ml / min to 2 ml / min; the column temperature is 28-32 DEG C; the method has good specificity and sensitivity for determination of bedaquiline fumarate cleaning verification target residues, is simple and convenient to operate, rapid in determination, simple and easy to implement, and overcomes the defects that TOC, chemical titration methods, conductivity methods, pH methods and the like which are commonly used at present do not have specificity.

The invention discloses a method for analyzing related substances and impurities in a reaction process of Mabazavir, relates to the field of medicine detection, and aims to provide a high-sensitivity and excellent-stability related substance analysis method for controlling the reaction process of Mabazavir, and the chromatographic conditions are as follows: a C18 chromatographic column (Waters Xselect CSH C18, 4.6 * 100mm, 3.5 mu m) of which the surface is charged and hybridized is adopted as a chromatographic column; a mobile phase A is a 0.05%-0.2% trifluoroacetic acid solution containing 0.1-1.0 mmol / L disodium ethylene diamine tetraacetate, a mobile phase B is acetonitrile, and isocratic elution is carried out according to the ratio of 55: 45; the column temperature is 40-60 DEG C; the flow velocity is 0.5 to 1.0 mL / min; the sample size is 5-20 [mu] l; and the operation time is 20-60 minutes. The method has the advantages of high detection sensitivity, good reproducibility, high stability and the like, and is suitable for detecting related substances controlled in the reaction process of the macavir.

The invention discloses a method for determining impurities in a desloratadine oral solution, the impurities comprise a desloratadine impurity 1, the determination method adopts a high performance liquid chromatography, and the detection conditions of the high performance liquid chromatography are as follows: a chromatographic column is an octyl silane bonded silica gel column or an efficiency equivalent column; the detection wavelength is 254 + / -2nm; the detector is an ultraviolet detector; the column temperature is 35-45 DEG C; the flow rate is 1.1 to 1.3 mL / min; mobile phases: a dipotassium phosphate buffer solution, methanol and acetonitrile; the elution mode is isocratic elution. The determination method disclosed by the invention is good in specificity, good in separation degree, high in sensitivity and good in accuracy, can fully meet the requirements of impurity determination, has important meanings for evaluating the quality of raw material medicines and the advantages and disadvantages of a preparation process, controlling the quality of a final product and detecting a stable sample, and is high in practicability in actual quality control work.

The invention discloses a method for detecting the content of effective components in a nerofloxacin malate capsule, and relates to the technical field of medicine detection and analysis, and the detection method comprises the following step: detecting the content of the effective components in the nerofloxacin malate capsule by adopting a high performance liquid chromatography. The invention provides the method for detecting the content of the effective components in the nerofloxacin malic acid capsule for the first time, and the inventor finds that the interference of non-effective components such as impurities and auxiliary materials in the nerofloxacin malic acid capsule can be effectively avoided by selecting a specific chromatographic column and a specific mobile phase for isocratic elution; the accuracy of detecting the content of the effective components in the nerofloxacin malic acid capsule is improved, the accurate quantification of the content of the nerofloxacin malic acid capsule is realized, and the blank in the prior art is filled.

The invention relates to the field of medicine detection, and particularly provides a method for detecting the residual content of triethanolamine by ion exchange-high performance liquid chromatography, and the chromatographic conditions in the method are as follows: a chromatographic column adopts a bonded cation exchange medium sulfonic group or carboxyl as a filler; a mobile phase is a phosphate buffer solution, and isocratic elution is carried out. According to the method disclosed by the invention, the triethanolamine does not need to be subjected to pre-column derivatization, and macromolecular protein and triethanolamine separation development (direct flow-through of macromolecular protein) is also not needed, so that the problem that the macromolecular protein is precipitated and removed to detect the triethanolamine when the gas chromatography is used is solved; and the problem that other detector modules such as a mass spectrum detector, an evaporative light detector and an electric conductivity detector need to be equipped and maintained is also solved. The method has the advantages of simple operation, accurate result, small interference and high sensitivity.

The invention discloses a double-column circulating chromatographic system which comprises an isocratic elution device, a gradient elution device, a pre-column valve, a chromatographic column device, a post-column valve, a detector device, a waste liquid tank, a fraction collection device, a reflux device and a connecting pipeline, the isocratic elution device and the gradient elution device are connected with the pre-column valve, the chromatographic column device and the post-column valve through connecting pipelines after being connected in parallel, the post-column valve is connected with the detector device and the waste liquid tank which are arranged in parallel through connecting pipelines, and the detector device is connected with the fraction collector through a connecting pipeline. The method has the beneficial effects that (1) not only can the purification efficiency and yield be improved, but also stable peak appearance time and a highly consistent purification spectrum can be obtained, so that stable impurity spectrum distribution is obtained, and continuous automatic production is realized; and (2) multi-time multi-system automatic circulation purification of the same system is realized, the purification efficiency is remarkably improved, human intervention and operation errors are reduced, the pollution risk is reduced, and industrialization of continuous flow purification is realized.

The invention provides a method for detecting the content of glycine and urotropine in glycine wastewater, and belongs to the technical field of analytical chemistry. The method comprises the following steps: firstly, obtaining a standard curve by utilizing a standard solution of glycine and urotropine, and then comparing the consistency of retention time of two main peaks of glycine and urotropine in a standard mixed solution and the retention time of a main peak in a sample to be detected, and substituting into the standard curve to obtain the content of glycine and urotropine in the sample to be detected. According to the method, when a standard mixed solution of glycine and urotropine is prepared, the weight ratio of glycine to urotropine is limited to be 1: 1, mobile phase ultrapure water and chromatographic grade methanol selected during high performance liquid chromatography testing are used as solvents, and during high performance liquid chromatography testing, an isocratic elution mode is adopted for elution, so that the content of glycine and urotropine in the mixed solution is greatly improved. Therefore, the obtained working curve prepared by using the respective chromatographic area and concentration data of glycine and urotropine has good linear correlation, and the test accuracy is further improved.

The invention relates to a supercritical fluid chromatographic separation method of bakuchiol, which comprises the following steps: dispersing a crude product in a solvent to prepare a test sample; carrying out supercritical fluid chromatographic separation on the test sample; the supercritical fluid chromatographic separation conditions are as follows: a mobile phase is a mixture of supercritical carbon dioxide and C1-C3 alcohol compounds in a volume ratio of (99.5-98.5): (0.5-1.5), and isocratic elution is performed; the stationary phase of the chromatographic column is octadecylsilane chemically bonded silica. The supercritical fluid chromatographic separation method of the bakuchiol makes up the research blank of analyzing and separating the bakuchiol by adopting the supercritical fluid chromatography in the traditional method, and can realize accurate detection and effective preparation of the bakuchiol. Meanwhile, the separation method is short in time consumption and good in separation effect.

The invention relates to the technical field of pharmaceutical analysis, in particular to a method for detecting ziyuglycoside II in an ovateleaf holly bark medicinal material and application of the method. Comprising the following steps: preparation of a reference substance solution, preparation of a test solution, liquid chromatography detection and data analysis, and the data analysis comprises calculation of the content of ziyuglycoside II in the ovateleaf holly bark medicinal material. Wherein the liquid chromatography conditions are as follows: a chromatographic column filler is octadecylsilane chemically bonded silica; the mobile phase is acetonitrile (A) and 0.1% phosphoric acid aqueous solution (B), and 38%-40% A isocratic elution is adopted, or 0-10 min, 35%-40% A; in 10-45 min, 40%-46% A gradient elution is carried out. The method for detecting the content of ziyuglycoside II in the ovateleaf holly bark medicinal material is established and is applied to whole-process detection of ziyuglycoside II in the ovateleaf holly bark medicinal material and a preparation thereof, and an analysis means is provided for quality control of the ovateleaf holly bark medicinal material and the preparation thereof.

The invention relates to the technical field of plant extraction, and provides a plurality of phenolic compounds in senecio scandens, and a preparation method and application thereof. The method comprises the following steps: crushing senecio scandens, adding ethyl acetate, and performing ultrasonic heating, stirring and extracting to obtain an extracting solution; carrying out rotary evaporation and vacuum concentration on the extracting solution to obtain a crude extract; dissolving the crude extract by using absolute ethyl alcohol through ultrasonic heating, carrying out gradient elution through a macroporous adsorption resin chromatographic column, and collecting an ethanol water eluent; and concentrating the ethanol water eluent under reduced pressure, stirring with a reverse-phase filler, loading with a dry method, packing with a wet method, and sequentially performing isocratic elution with a reverse-phase chromatographic column and purification with a gel column. The dissolution efficiency of phenolic compounds in senecio scandens is improved through ultrasonic and mild heating, the problems that components are degraded due to high temperature in traditional reflux extraction and time and solvent are consumed in dipping extraction are solved, and target component residues are reduced; and then through gradient elution of a chromatographic separation column, isocratic elution of a reversed-phase chromatographic column and purification of a gel column, the problem that phenols are similar in structure and easy to co-elute is accurately solved.

The present application relates to the field of pharmaceutical analysis, and particularly relates to a method for determining the content of cetirizine hydrochloride and preservatives in cetirizine hydrochloride oral solution. The method provided by the present application uses octadecyl bonded silica as the filler of the chromatographic column, uses a mixed solution with specific composition and proportion as the mobile phase, adopts isocratic elution, uses a content volumetric pipette to prepare the test sample solution, injects the test sample solution and the mixed control solution into the liquid chromatograph respectively to perform liquid chromatography, thereby obtaining the chromatogram of the test sample solution and the chromatogram of the mixed control solution respectively; and then according to the external standard method, the content of cetirizine hydrochloride, the content of the hydroxy methylbenzoate preservative and the content of the hydroxy propylbenzoate preservative in the cetirizine hydrochloride oral solution are calculated by the peak area. The method has strong specificity, high accuracy, good precision, linear relationship and stability, and is conducive to the evaluation of sample quality.

The present invention relates to a method for analyzing and detecting related substances of desloratadine, and belongs to the technical field of drug detection and analysis. In order to solve the problem of low detection efficiency and low precision in the existing detection, a method for analyzing and detecting related substances of desloratadine is provided, and high performance liquid chromatography is used for detection, including the following chromatographic conditions: isocratic elution is adopted; 1.0g to 1.1g of sodium dodecyl sulfate and 0.86g to 0.88g of sodium dihydrogen phosphate are contained in each 550ml of water in the mobile phase; the volume ratio of water: triethylamine: acetonitrile: methanol in the mobile phase is 550: 1.4 to 1.6: 285 to 320: 145 to 156; phosphoric acid is used to adjust the pH value to 2.8 to 3.3. The present invention can produce peaks and can be separated from each other, with good separation, and the peaks of each impurity such as impurity A and the main peak do not overlap, so that high-efficiency detection and analysis are achieved, and the detection accuracy is high.

The invention relates to a method for analyzing and detecting a non-azonetin enantiomer, which adopts normal-phase high performance liquid chromatography and takes normal hexane-ethanol-trifluoroacetic acid as a mobile phase to detect the non-azonetin enantiomer, and the specific chromatographic conditions are as follows: a chromatographic column is prepared by covalently bonding amylose-tri (3, 4, 6-trimethyl-1, 3-pentanediol) on the surface of silica gel; 2, 5-dichlorophenyl carbamate is used as a filling agent (IE, 4.6 * 250 mm, 5.0 [mu] m); a mobile phase: n-hexane: ethanol: trifluoroacetic acid = 500: 500: 1 (V / V / V); the flow rate is 1.0 ml / min; the column temperature is 30 DEG C; the sample size is 20 [mu] l; the detection wavelength is 280 nm; the elution gradient is isocratic elution. The invention provides a high performance liquid chromatography method for analyzing the enantiomer of the fiazonetin, the complete separation of the fiazonetin and the enantiomer of the fiazonetin can be realized by adopting the method, and the separation degree of a main component and the enantiomer is greater than 1.5.

The invention discloses a method for detecting phenyl sulfide in rectification residual liquid of 2, 4-dichlorophenol through high performance liquid chromatography, and belongs to the technical field of chemical detection and analysis. The method comprises the following steps: dissolving a to-be-detected 2, 4-dichlorophenol rectification residual liquid sample to prepare a to-be-detected sample, and preparing phenyl sulfide standard substance solutions with different concentrations; the method comprises the following steps: determining a to-be-detected sample and a phenyl sulfide standard substance solution by adopting a high performance liquid chromatograph, drawing a standard curve and a linear regression equation according to a detection result of the phenyl sulfide standard substance solution, and analyzing the phenyl sulfide in the sample by combining the linear regression equation and a chromatographic peak map of the to-be-detected sample, wherein the mobile phase comprises a phase A and a phase B, the phase A is an aqueous solution of phosphate buffer salt, the phase B is methanol, and an isocratic elution mode is adopted. According to the present invention, with the method, the accurate determination of the phenyl sulfide content in the 2, 4-dichlorophenol rectification residual liquid is achieved, the timely and accurate data guidance is provided for the 2, 4-D production process, and the target of production cost saving is ultimately achieved.

The invention relates to the technical field of pharmaceutical analysis, in particular to a chromatographic method for determining optical isomers in a carbidopa raw material medicine and a preparation thereof by using an HPLC (High Performance Liquid Chromatography) method. The detection method is simple, convenient, rapid and accurate to operate, and specifically comprises the following steps: dissolving a proper amount of a sample with a solvent, diluting to a certain concentration, taking a certain volume of the sample, carrying out isocratic elution at a certain column temperature by adopting a high performance liquid chromatography, using a hand-type chromatographic column, a mobile phase A and a mobile phase B, and carrying out quantitative analysis by adopting a self-control method with correction factors. And calculating the isomer in the test solution. The method is good in specificity, solution stability, linearity, repeatability, intermediate precision and durability, and the detection result is accurate and reliable through verification.

The application is suitable for the field of in-vitro diagnosis equipment, and discloses a liquid chromatograph. The liquid chromatograph comprises a liquid phase fluid conveying assembly, a chromatographic column, a detector and a controller; the liquid phase fluid conveying assembly comprises a storage component, a first driving component and a second driving component independent of the first driving component, the first driving component is used for driving a first liquid phase fluid from a first container to the storage component and driving a second liquid phase fluid from a second container to the storage component, so that the first liquid phase fluid and the second liquid phase fluid are mixed in the storage component at a preset ratio to form a third liquid phase fluid of a single concentration and are stored in the storage component; and the second driving component is used for driving the third liquid phase fluid to flow through the chromatographic column from the storage component, so that the third liquid phase fluid elutes a test liquid adsorbed on the chromatographic column. The application can realize the function of isocratic elution by using the liquid phase fluid prepared on line from two liquid phase fluids.

The invention belongs to the technical field of analytical chemistry, and discloses a method for detecting creatinine in a creatine product, which comprises the following steps: (1) precisely weighing a sample, adding a buffer solution, carrying out vortex oscillation dissolution, volume metering, shaking up, centrifuging, and passing through a water phase filter membrane to obtain a creatine test solution; (2) a creatine test solution is taken, a liquid chromatograph is adopted for liquid phase detection, and the liquid chromatography conditions are as follows: an SCX chromatographic column is adopted, an ammonium dihydrogen phosphate solution is taken as a mobile phase for isocratic elution, an ultraviolet detector is adopted, and the content of creatinine is obtained according to a liquid phase detection result. According to the method, the situation that the detection result of the creatinine in the creatine product is virtually high can be remarkably reduced, accurate quantification of the creatinine byproduct creatinine is achieved, and a more perfect data basis is provided for quality control of the creatine product.

The invention provides a method for simultaneously determining ritocaine and prilocaine in blood plasma based on a liquid chromatography-tandem mass spectrometry (LC-MSMS) technology. The specific operation of the method comprises the following steps: adding an internal standard solution and an organic solvent into a plasma sample, and ensuring full extraction of lidocaine and prilocaine through vortex mixing. And separating by using a centrifugal technology, and collecting supernate as a pretreated sample to be detected. An Eclipse Plus C18 chromatographic column is adopted for isocratic elution, effective separation of lidocaine and prilocaine is achieved, and then a sample is subjected to mass spectrometric detection. A standard curve is drawn based on the mass spectrum peak area ratio, a regression equation is obtained, and the concentration of lidocaine and prilocaine in the sample to be detected is obtained through calculation. The method has the characteristics of simplicity and convenience in pretreatment operation, low plasma consumption, short analysis time and high sensitivity, and is suitable for detection of lidocaine and prilocaine in plasma and clinical pharmacokinetic research of the lidocaine cream.

The invention discloses a method for detecting sialic acid in a dairy product. The method comprises the following steps: pretreating raw materials: weighing a uniformly mixed liquid dairy product, adding water for diluting, adding a precipitant consisting of potassium ferrocyanide and zinc acetate, uniformly shaking, adding water for fixing the volume, uniformly shaking, and filtering with a filter membrane of 0.5 mu m or less to obtain a filtrate; the concentration of the liquid dairy product is 1-10g / 100mL, the concentration of the potassium ferrocyanide is 0.1-0.26 g / 100mL, and the concentration of the zinc acetate is 0.2-0.55 g / 100mL after the water is added to a constant volume; a chromatographic column is a hydrogen type cation chromatographic column, a 0.005-0.01 mol / L sulfuric acid aqueous solution is used as an eluent for isocratic elution, and after elution, a PAD detector is adopted for detection under the detection wavelength of 210-220 nm. The method is suitable for detecting sialic acid in milk, and has the advantages of simple sample treatment, low treatment cost and accurate detection.

The invention provides a method for determining the content of two sesquiterpenoids in a turmeric extract, and belongs to the technical field of medicine detection.The quality detection method comprises the steps that the turmeric extract is taken to be prepared into a test solution, then acetonitrile (A) and 0.08-0.12 wt% phosphoric acid aqueous solution (B) are subjected to isocratic elution with the ratio of 65-75: 25-35, then an external standard one-point method or a standard curve method is used for determining the content of the two sesquiterpenoids in the turmeric extract, and the content of the two sesquiterpenoids in the turmeric extract is determined. And calculating the content of aryl turmerone and beta-turmerone in the turmeric extract. The method for determining the content of the two sesquiterpene compounds in the turmeric extract is innovatively established, accurate quantitative analysis of the target sesquiterpene component is realized for the first time by optimizing chromatographic separation conditions and detection parameters, the detection blank of an existing standard system is filled, and the method has a wide application prospect. And a key technical support is provided for constructing a turmeric extract multi-dimensional quality control system.

The application provides a qualitative and quantitative detection method of polynaphthalene formaldehyde sulfonate sodium salt in a pesticide preparation, comprising the following steps: S10, solution preparation: preparing a standard sample solution, a series of concentration standard solutions and a sample solution by using pure water as a solvent; S20, chromatographic detection: adopting high performance liquid chromatography, using a C18 chromatographic column as a stationary phase, using a mixed solution of a water solution containing sodium dodecyl sulfonate and acetonitrile as a mobile phase for isocratic elution, and detecting at a wavelength of 240 nm; S30, qualitative determination: comparing the chromatographic peak retention time of the standard sample solution and the sample solution, and determining whether the polynaphthalene formaldehyde sulfonate sodium salt is contained according to the relative deviation; and S40, quantitative determination: drawing a standard curve according to the concentration and peak area of the series of concentration standard solutions, and calculating the content according to an external standard method. The application realizes accurate qualitative and quantitative determination of the polynaphthalene formaldehyde sulfonate sodium salt by combining chromatographic separation and ultraviolet detection, has the advantages of strong specificity, high accuracy, good reproducibility and simple operation, and is suitable for detection of various pesticide preparations.

The invention relates to the technical field of pharmaceutical analysis, in particular to a method for detecting the content of chloride ions in methotrexate injection. According to the method, ion chromatography is adopted for detection, a chromatographic column is an anion chromatographic column, a mobile phase is 0.015 mol / L anhydrous sodium carbonate solution, and the mobile phase is subjected to isocratic elution. By adopting the method disclosed by the invention, the content of chloride ions in the methotrexate injection can be effectively detected, the method has the advantages of strong specificity, high sensitivity and the like, and the quality of the methotrexate injection is effectively guaranteed.

The invention discloses a method for detecting lactic acid in displacement liquid, which comprises the following steps: (1) pretreating the displacement liquid, namely pretreating a sample by using an alkaline solution, standing, adding a proper amount of acid solution for neutralization, filtering by using a filter membrane, and taking a subsequent filtrate to obtain a test solution; and (2) detecting the test solution by adopting a high performance liquid chromatography under the chromatographic conditions that a mobile phase is a phosphoric acid aqueous solution, and isocratic elution is carried out. The mobile phase is simple to prepare, various reagents are not needed, the detection cost is saved, the experimental error is reduced, and the lactic acid in the displacement liquid can be accurately analyzed. The phosphoric acid water is used as a mobile phase, the pH value of the phosphoric acid water is about 2, the activity of silicon hydroxyl in the chromatographic column can be just inhibited, long-time use of the chromatographic column is facilitated, the sample peak shape can be improved, and trailing can be reduced.

The invention relates to a quality control method of artemisia apiacea or an artemisia apiacea extract, which comprises the following steps: respectively detecting a test solution and a reference solution by adopting a high performance liquid chromatography, generating a reference fingerprint spectrum by adopting a median method, and calculating the similarity of each common peak; and calculating the content according to the peak areas of artemisinin, artemisinic acid and dihydroartemisinic acid in the chromatograms of the sample to be detected and the reference substance by an external standard method. The mobile phase A is a tetrahydrofuran phosphate aqueous solution, the mobile phase B is acetonitrile, isocratic elution is carried out, and the stationary phase is Agilent Infinity Lab Poroshell 120EC-C18 250mm * 4.6 mm, 2.7 mu m, Caprisil C18 250mm * 4.6 mm, 3.0 mu m or an equivalent column. The method is high in accuracy and good in stability and reproducibility, can be used as a detection method for the fingerprint spectrum of the artemisia apiacea medicinal material, and can be used for simultaneously determining the contents of artemisinin, artemisinic acid and dihydroartemisinic acid.

The invention relates to a method for measuring the concentration of cefadroxil in K2EDTA human plasma through LC-MS / MS. The method comprises the following steps: preparing a standard curve solution containing cefadroxil d4 by taking K2EDTA human plasma as a matrix, preparing a test solution containing cefadroxil, and precipitating the solution by using acetonitrile; determining the concentration of the test solution containing cefadroxil after precipitation by using an internal standard method; a liquid chromatography tandem mass spectrometer is used for determination, a mobile phase of liquid chromatography is composed of a mobile phase A and a mobile phase B, the mobile phase A is an acetic acid aqueous solution, and the mobile phase B is acetonitrile; the elution procedure of the liquid chromatography is isocratic elution, the volume content of acetonitrile in a mobile phase is 10-30%, and the flow velocity of the mobile phase is 0.4-0.8 mL / min. By optimizing chromatographic conditions and mass spectrum parameters, an efficient and accurate cefadroxil concentration detection method is provided, and the accuracy and reliability of data are ensured.

The invention relates to the related technical field of measurement of the content of fluticasone propionate emulsifiable paste, in particular to a method for detecting the content of paste by adopting a high performance liquid chromatography, and particularly relates to a method for measuring the content of fluticasone propionate emulsifiable paste by adopting the high performance liquid chromatography, in particular to a method for detecting the content of fluticasone propionate emulsifiable paste by adopting the high performance liquid chromatography. Comprising the following steps: preparing a mobile phase from a diammonium hydrogen phosphate buffer solution (the pH value is 2.0-5.0), methanol and acetonitrile by adopting an octadecyl silane bonded silica gel column; and carrying out isocratic elution. According to the method disclosed by the invention, the diammonium hydrogen phosphate buffer solution-methanol-acetonitrile with a specific ratio is adopted as a mobile phase, and a chromatographic system in which an octadecyl silane bonded silica gel column and a guard column are connected in series is combined, so that the interference of oily auxiliary materials in a cream matrix is effectively eliminated, and the detection specificity and the separation effect are remarkably improved; besides, key chromatographic parameters such as column temperature, flow velocity and detection wavelength are optimized, and a scientific test sample pretreatment process is matched, so that the accuracy and reliability of a content measurement result are guaranteed.

The invention provides a BINAP purity detection method, and relates to the technical field of chemical detection. According to the detection method, a BINAP reference substance solution and a to-be-detected substance solution are prepared, the BINAP reference substance solution and the to-be-detected substance solution are detected through high performance liquid chromatography, a mobile phase A and a mobile phase B are arranged in the detection process, the mobile phase A is a mixed solution of phosphoric acid and water, the mobile phase B is a mixed solution of phosphoric acid and acetonitrile, and the mobile phase B is a mixed solution of phosphoric acid and acetonitrile. And a mobile phase is subjected to constant-gradient elution. According to the method, the defects in the prior art are overcome, isocratic elution is carried out by utilizing the high performance liquid chromatography and combining proper mobile phase setting, the BINAP and related substances thereof can be effectively detected, the separation degree R can reach 1.5 or above, a baseline is stable, drifting does not occur, accurate determination of the purity of the BINAP can be realized, the reproducibility is good, and the operation is simple and convenient.

The invention relates to the technical field of pharmaceutical analysis, in particular to a method for detecting impurities of 22-ene-ursodesoxycholic acid and 22-ene-chenodesoxycholic acid in ursodesoxycholic acid. According to the method, a high performance liquid chromatograph is used, a sodium dihydrogen phosphate dihydrate aqueous solution-acetonitrile is used as a mobile phase, isocratic elution is adopted, an octyl silane bonded silica gel column is used as a chromatographic column for separation, and an ultraviolet detector is used for detection. The detection method can effectively separate and identify 22-ene-ursodesoxycholic acid and 22-ene-chenodesoxycholic acid impurities in ursodesoxycholic acid, methodology verifies that all inspection indexes meet regulations, the detection result is accurate and reliable, and the method has the advantages of being simple, convenient, exclusive, accurate and high in sensitivity. And a guarantee is provided for monitoring the quality stability and clinical medication safety of the ursodesoxycholic acid.