260 results about "Drug analysis" patented technology

The invention relates to the field of pharmaceutical analytical chemistry, in particular to a method for determining tandospirone and salt intermediates thereof, high performance liquid chromatography is adopted, and chromatographic conditions include that a chromatographic column with octadecylsilane chemically bonded silica as a filler is adopted, and gradient elution is performed by a mobile phase A and a mobile phase B; wherein the mobile phase A consists of a first water phase and acetonitrile; the mobile phase B is composed of a second water phase and acetonitrile; the first water phase is a water solution containing monopotassium phosphate and sodium hexanesulfonate, and the pH value of the first water phase is 3.0-3.8; the second water phase is an aqueous solution containing monopotassium phosphate and sodium hexanesulfonate, and the pH value of the second water phase is 1.8-2.6. The testing method disclosed by the invention has good specificity, accuracy and repeatability, and can be used for monitoring the quality of the tandospirone raw material medicine.

The invention relates to the technical field of pharmaceutical analysis, in particular to a thin-layer chromatography identification method of vitality-preserving decoction and a preparation thereof. Comprising the following steps: S1, extracting a sample to be detected by using diethyl ether, and preparing a test solution; s2, preparing a cinnamaldehyde reference substance solution and a 6-gingerol reference substance solution; the method further comprises at least one of the steps S3 and S4; s3, dripping the test solution and the cinnamaldehyde reference solution on the same thin-layer plate, developing with a first developing solvent, and identifying the cinnamon; the first developing solvent comprises petroleum ether and ethyl acetate in a volume ratio of (15-20): 3; s4, dripping the test solution and the 6-gingerol reference substance solution on the same thin-layer plate, developing with a second developing solvent, and identifying the ginger; the second developing solvent is prepared from petroleum ether, trichloromethane and ethyl acetate according to the volume ratio of (2-4): (1-2): (1-3). The method is good in overall separation effect, clear in spots, good in specificity and durability, and capable of identifying the medicine flavors of cinnamon and ginger in the vitality-preserving decoction and the preparation thereof.

The invention belongs to the technical field of pharmaceutical analysis, and discloses a method for determining two potential genotoxic impurities in carbon [13C]-urea by gas chromatography. Comprising the following steps: (1) preparing a sample solution; (2) preparing a reference solution; (3) taking nitrogen as carrier gas, and detecting by adopting a medium-polarity or weak-polarity chromatographic column separation system; and (4) calculating by a peak area through an external standard method to obtain the accurate contents of methyl carbamate and ethyl carbamate in the carbon [13C]-urea. The method disclosed by the invention is simple to operate, good in specificity, linearity, precision and accuracy and high in sensitivity, and can realize accurate detection of residual potential genotoxic impurities, namely methyl carbamate and ethyl carbamate, in the carbon [13C]-urea.

The invention belongs to the technical field of pharmaceutical analysis, and particularly relates to a method for separating and determining nafamostat mesylate SM2 and related impurities thereof. The method is a high performance liquid chromatography, and comprises the following steps: by taking octadecylsilane chemically bonded silica as a chromatographic column filler, a potassium hexafluorophosphate solution as a mobile phase A and acetonitrile as a mobile phase B, separating nafamostat mesylate SM2 and related impurities thereof through linear gradient elution; and detecting by using detection wavelengths of 200 nm to 240 nm and 250 nm to 280 nm to obtain a chromatogram, so that effective determination of the nafamostat mesylate SM2 and the related impurities thereof is realized. The method provided by the invention adopts common buffer salt as a mobile phase, and has the characteristics of short analysis time, strong specificity, high sensitivity and good reproducibility.

The invention relates to the technical field of drug analysis and detection, in particular to a method for detecting related substances in moxifloxacin hydrochloride bulk drugs. According to the detection method provided by the invention, the separation efficiency of the known impurity (impurity F) can be improved, and the separation degree between the main component and the adjacent impurity can reach 1.5 or above; in addition, a solvent formula is optimized, so that a test sample is more stable, and the detection method is more accurate; the detection accuracy is improved, and the recovery rate is controlled within the range of 93-102%.

The invention relates to the technical field of pharmaceutical analysis, and particularly discloses a high performance liquid chromatography-mass spectrometry tandem method (HPLC-MS / MS) for detecting a genotoxic impurity L-alanine isopropyl ester in an emtricitabine-propofol tenofovir tablet. By optimizing chromatographic column selection, a mobile phase gradient elution procedure and mass spectrometric detection parameters, the method realizes exclusive, sensitive and accurate detection of the L-isopropyl alanine. The methodological verification result shows that the detection limit is 1.00 ng / mL, the quantification limit is 2.00 ng / mL, the linear range is 2.00-100.00 ng / mL (the correlation coefficient r is equal to 0.9994), the recovery rate is stabilized between 92% and 98%, and the precision and repeatability are good. The detection method has the advantages of high sensitivity and strong selectivity, is suitable for quality control of emtricitabine propofol tenofovir tablets, meets the control requirements of ICH M7 guide on genotoxic impurities, and has good practicability and popularization value.

The invention relates to the technical field of pharmaceutical analysis, in particular to a method for detecting the content of guanidine nitrate by precolumn derivatization-high performance liquid chromatography, which comprises the following steps: oscillating and uniformly mixing a guanidine nitrate reference substance or sample and pure water at room temperature, adding sulfuric acid concentrated liquor in cold water bath to perform derivatization reaction, after the reaction is finished, placing at room temperature, and performing column chromatography to obtain the guanidine nitrate content. Adding liquid caustic soda for neutralization, carrying out gradient constant volume by using a mobile phase, and filtering by using a microporous filter membrane to respectively obtain a derivatization reference solution and a derivatization sample solution; and respectively injecting the derivatization reference substance solution and the derivatization sample solution into HPLC, recording peak areas, and calculating the content of guanidine nitrate in the sample by adopting an external standard method. The guanidine nitrate sample is pretreated through the precolumn derivatization reaction, the guanidine nitrate derivative generated through the reaction has the advantages of being high in stability and easy to separate, ammonium nitrate and nitric acid impurities can be effectively prevented from interfering the detection result, the explosive picric acid is not adopted in the detection method, and the detection method is simple, safe and easy to implement.

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.

This invention belongs to the field of pharmaceutical analysis, specifically relating to a method for constructing a fingerprint spectrum of Shenfushu granules. The method for constructing a fingerprint spectrum of Shenfushu granules provided by this invention features high accuracy, high stability, good repeatability, good specificity, and strong specificity. The fingerprint spectrum analysis method for Shenfushu granules, a traditional Chinese medicine preparation for treating chronic renal failure, established by this invention can not only qualitatively analyze and identify the seven chemical components contained in this preparation, but also simultaneously present the characteristic peaks of five traditional Chinese medicines in the prescription, achieving the goal of overall quality control of multiple medicinal ingredients.

The invention relates to the technical field of pharmaceutical analysis, and particularly discloses a method for simultaneously determining the content of benzyl alcohol and ethyl oleate. The method for simultaneously measuring the content of benzyl alcohol and ethyl oleate comprises the following steps: S1, mixing a sample to be measured with a low alcohol aqueous solution, freezing, adding non-polar straight-chain alkane, extracting and layering to obtain a liquid to be measured; s2, an Agilent DB-WAX chromatographic column is adopted and matched with optimized chromatographic conditions such as a heating procedure, gas chromatography detection is conducted on the to-be-detected liquid, and therefore simultaneous quantitative determination of benzyl alcohol and ethyl oleate is achieved. The method provided by the invention has the advantages of simplicity and convenience in operation, high accuracy, good repeatability, strong applicability and the like, and solves the problems of poor separation degree of benzyl alcohol and ethyl oleate and low detection efficiency in the prior art.

The application provides a method for detecting impurities in leboregen starting material LBS5, and belongs to the field of pharmaceutical analysis chemistry. S ,5 R )‑1‑(3‑fluorophenyl)‑3‑oxabicyclo[3.1.0]hexan‑2‑one. The method adopts high performance liquid chromatography, can simultaneously and accurately quantify one degradation impurity and four process impurities in LBS5, and has strong specificity, high sensitivity, good accuracy, good reproducibility and stable and reliable method. The method can realize the control of the impurities, ensures the safety of LBS5 as a pharmaceutical intermediate, further ensures the safety of a preparation of LBS5, reduces the risk of drug use, simultaneously reduces the difficulty of subsequent synthesis steps, realizes rapid, economic and environmental protection production. The method is suitable for laboratory research and development, and is also suitable for quality control in commercial production.

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.

A method for maintaining a gene description dataset associated with a plurality of genes with respect to a given disease, wherein the gene description dataset is a human- comprehensible text-based dataset generated by a Large Language Model (LLM); maintaining a dataset of drug mechanisms of action (MOAs) associated with a plurality of drugs; embedding the gene descriptions and the MOAs into high-dimensional vectors using a text embedding technique to generate gene description vectors and MOA vectors; calculating distances between the gene description vectors and the MOA vectors to generate distance scores; and ranking the drugs for the given disease based on an aggregated distance score between the MOA vectors and the vectors of genes associated with the given disease.

The invention discloses a fingerprint spectrum of Huanglong cough-relieving granules and a construction method, and relates to the technical field of pharmaceutical analysis. The construction method comprises the following steps: (1) preparation of a test solution: taking Huanglong cough-relieving granules, and adding an extraction solvent for extraction; (2) preparing a reference substance solution; (3) preparing a reference medicinal material solution; (4) chromatographic conditions: octadecylsilane chemically bonded silica is used as a filler; the mobile phase A is acetonitrile, the mobile phase B is 0.1-0.2% phosphoric acid, the flow rate is 0.38-0.42 ml / min, the column temperature is 29-31 DEG C, the detection wavelength is 210 nm in 0-17 min, and the detection wavelength is 270 nm in 17-48 min; and (5) absorbing the solution, and adding the solution into a liquid chromatograph for detection. The fingerprint spectrum constructed by the method can systematically reflect the material basis, is relatively good in precision, repeatability and stability, and can be used for quality control of the Huanglong cough-relieving granules.

The present application relates to the technical field of pharmaceutical analysis, and in particular to a combined analysis method for exploring the effect of Huangkui capsules on improving chronic kidney injury of tacrolimus based on metabolomics and proteomics. The combined analysis method of the present application explores how Huangkui capsules improve the mechanism of chronic kidney injury of tacrolimus from multiple dimensions, which is beneficial to in-depth analysis of the specific effects of Huangkui capsules at the molecular, cellular and tissue levels, reveals the key path and regulation mechanism of kidney protection, and can also provide a scientific basis for optimizing clinical application, further promoting the modernization of traditional Chinese medicine and its wide application in the treatment of kidney disease.

The invention relates to the technical field of pharmaceutical analysis equipment, and discloses pharmaceutical active component quantitative analysis equipment which comprises a chromatographic column, the chromatographic column comprises a hollow column body, a filter screen is fixedly arranged at the lower end in the column body, a stationary phase is arranged above the filter screen, a piston is arranged above the stationary phase, and the piston is connected with a driving part; the piston comprises a first shell facing the stationary phase, a second shell is coaxially arranged on the side, away from the stationary phase, of the first shell in a sliding mode, an elastic supporting piece is arranged between the first shell and the second shell, a plurality of connecting holes are coaxially formed in the bottom of the first shell and the bottom of the second shell, liquid discharging columns are arranged in the connecting holes, and liquid inlets are formed in the tops of the liquid discharging columns. A liquid outlet is formed in the side wall of the bottom of each liquid discharging column, the multiple liquid discharging columns are connected with a driving mechanism, and the second shell is connected with a liquid inlet pipe. According to the invention, the state of a stationary phase bed layer can be actively adjusted, and uniform introduction and dispersion of liquid medicine are realized, so that the chromatographic separation efficiency and the quantitative analysis accuracy are improved.

The present application belongs to the field of pharmaceutical analysis, and particularly relates to a dissolution determination method for soft capsule preparation, which installs a screen on the upper side of the stirring paddle of a dissolution device, so that when the soft capsule shell has a large crack and large oil drops appear, the large oil drops can be dispersed into small droplets through the screen, thereby ensuring that the drug dispersion measurement result in the dissolution cup is scientific and reasonable.

The invention relates to the technical field of pharmaceutical analysis, in particular to a method for detecting vitamin D3 related substances in vitamin D drops, which comprises the following steps: (1) taking the vitamin D drops in a brown measuring flask, adding methanol for extraction, freezing to solidify oil drops, pouring methanol liquid, performing rotary evaporation under reduced pressure until the methanol liquid is dry, adding isooctane for dissolving to obtain a mass localization solution; (2) measuring and injecting into a purification chromatograph, accurately collecting the effluent in the time period according to the appearance time of the previtamin D3 and the impurity E in the impurity positioning solution, blow-drying with nitrogen, and adding isooctane for dissolving to obtain a test solution; (3) precisely measuring 100 [mu] l of the test solution, placing the test solution in a 10ml brown measuring flask, diluting with isooctane to a constant volume to a scale, and uniformly shaking to obtain a control solution; and (4) precisely measuring 100 [mu] l of the contrast solution and 100 [mu] l of the test solution, respectively injecting into an analysis liquid chromatograph, and recording chromatograms. According to the method, the interference of oily matrixes is removed, and various impurities in the vitamin D drops can be effectively, economically and quickly measured.

The application relates to the technical field of pharmaceutical analysis, and discloses a pharmacokinetic analysis method of Tongwei Xiaozheng medicinal liquid, which adopts Q-Orbitrap high-resolution liquid chromatography-mass spectrometry to analyze the concentration of Jasmonic acid in blood components of the Tongwei Xiaozheng medicinal liquid in rat plasma, establishes a plasma concentration determination method for the blood original component Jasmonic acid, carries out methodological verification such as specificity, precision and accuracy, and then calculates pharmacokinetic parameters. In the Tongwei Xiaozheng medicinal liquid, 92 blood components are identified, 17 of which are original components and 75 of which are metabolites, the application firstly determines that Jasmonic acid is one of the blood original components of the Tongwei Xiaozheng medicinal liquid, and reveals the pharmacokinetic characteristics of the Jasmonic acid in normal and model rats. The method has strong specificity, high sensitivity and good reproducibility, and can provide a scientific basis for the research on the pharmacodynamic material basis of the Tongwei Xiaozheng medicinal liquid, the establishment of quality control standards and the clinical rational use of drugs.

The present application relates to the technical field of pharmaceutical analysis, and specifically discloses a method for detecting the purity of doxycycline for injection. The present application mainly solves the problems caused by ion pair reagent and high-salt buffer in the existing chromatographic method, such as serious pollution of the system pipeline and the chromatographic column, difficulty in connecting with mass spectrometry for impurity structure identification, and insufficient separation degree of key polar impurities such as 4-epi doxycycline. The present application purifies the sample by physical dilution and filtration, and prepares uniform aerosol by ultrasonic atomization. The ion mobility spectrometry technology is adopted to realize the efficient separation of gas-phase ions under a weak electric field according to the difference in ion collision cross section (CCS) value, and the epimer which is difficult to distinguish by traditional methods can be excellently separated. The multi-modal sensor is used to synchronously collect ultraviolet, fluorescent and terahertz multi-dimensional optical signals. Finally, based on the intrinsic physical parameter database, the intelligent analysis is carried out by using the machine learning algorithm, and the qualitative and quantitative results are automatically output.

The invention provides a preparation method of a bifonazole impurity and application of the bifonazole impurity in quality control, and belongs to the technical field of organic chemistry. The invention provides a synthesis method of bifonazole impurities IMPM and IMPN by taking 4-bromobenzophenone as an initial raw material and application of the bifonazole impurities IMPM and IMPN in detection and / or control of the quality of bifonazole. The synthesis method of the bifonazole impurities IMPM and IMPN provided by the invention has the beneficial effects that the process route is simple, and the operation is convenient. The synthesis of the impurities is beneficial to development of a pharmaceutical analysis method, provides a reference substance for qualitative and quantitative analysis for detection of a bifonazole intermediate, is more beneficial to product quality control, and provides a guarantee for safe medication of bifonazole.

The invention belongs to the technical field of medicine analysis and detection, and particularly relates to a high performance liquid chromatography method for related substances of a flutemevitamin three-component preparation. According to the method, a specific chromatographic column, a mobile phase type, a mobile phase proportion and a gradient elution procedure are used, and only when the parameters are met at the same time, good detection separation degree, sensitivity and specificity can be ensured, so that accurate and rapid detection of related substances in the flutemevir three-component preparation is realized; the successful application of the technology is helpful for improving the quality level of a medicinal preparation, ensuring the medication safety of a patient, and making a positive contribution to the development of the field of medicine research and development.

This invention relates to the field of pharmaceutical analysis technology, specifically to a method for determining the content of deoxycholic acid injection. The detection method employs high-performance liquid chromatography (HPLC) with an ultraviolet (UV) detector. The HPLC chromatographic conditions are as follows: the column is an octadecylsilane-bonded silica column; the column dimensions are 4.6 × 150 mm, and the packing diameter is 3 μm; the detection wavelength is 220 nm; the mobile phase is 0.1% formic acid aqueous solution – 0.1% formic acid acetonitrile solution (42:58). Compared with existing technologies, UV detectors are more readily available than CAD detectors. This invention achieves quantitative detection of deoxycholic acid injection content by controlling the HPLC conditions of the UV detector. This method exhibits baseline stability, good specificity, accuracy, and precision, and is of significant importance for the quality control of deoxycholic acid injection.

The invention discloses a method for detecting related substances of a trans-4-[(2-amino-3, 5-dibromobenzyl) amino] cyclohexanol hydrochloride intermediate, and belongs to the technical field of pharmaceutical analysis. According to the detection method, 9 impurities, namely an impurity A, an impurity B, an impurity C, an impurity D, an impurity E, an impurity F, an impurity G, an impurity H and an impurity I, in the trans-4-[(2-amino-3, 5-dibromobenzyl) amino] cyclohexanol hydrochloride intermediate are simultaneously detected by utilizing a high performance liquid chromatography. The detection method can effectively monitor the impurity content of the trans-4-[(2-amino-3, 5-dibromobenzyl) amino] cyclohexanol hydrochloride intermediate, has the advantages of simple operation, high separation degree, strong specificity, high accuracy and good accuracy and durability, is suitable for central quality control in industrial production, and can ensure the quality of the intermediate and the finished product medicine.

The invention relates to the technical field of pharmaceutical analysis, in particular to an HPLC (High Performance Liquid Chromatography) fingerprint spectrum construction method and application of a twelve-ingredient numbness pain liniment. The construction method comprises the following steps: preparing a test solution; preparing a reference substance solution; and HPLC determination. The HPLC fingerprint spectrum construction method of the twelve-ingredient numbness pain liniment is provided for the first time, and the method has the advantages of being high in precision, good in reproducibility, high in stability and good in durability. Meanwhile, the method disclosed by the invention can be used for detecting the contents of three components including polydatin, stilbene glucoside and emodin in the twelve-ingredient numbness pain liniment at one time. Technical support is provided for comprehensively improving the product quality standard of the twelve-ingredient arthralgia pain liniment and optimizing the preparation process, identifying true and false and carrying out follow-up material basic research of the twelve-ingredient arthralgia pain liniment.

This invention belongs to the field of pharmaceutical analysis technology and relates to a method for detecting the content of dimethicone and silica in simethicone oral sol-coating membranes. The simethicone oral sol-coating membrane is dissolved in dimethyl sulfoxide, followed by a first extraction with n-hexane, and then a second extraction with sodium dodecyl sulfate. The material from the second extraction is centrifuged, and the supernatant is dehydrated to obtain a test solution. The absorbance of the test solution is detected using infrared spectrophotometry to obtain an infrared absorption spectrum. Data on the Si-CH3 and Si-O absorption peaks are obtained from the infrared absorption spectrum. The content of dimethicone is calculated based on the Si-CH3 absorption peak data, and the content of silica is calculated based on the Si-CH3 and Si-O absorption peak data. This invention can simultaneously detect the content of dimethicone and silica in simethicone oral sol-coating membranes with high accuracy and good repeatability.

The invention discloses a hydrophilic chromatographic stationary phase simply modified by polyethyleneimine and carbon dots as well as a preparation method and application of the hydrophilic chromatographic stationary phase, and belongs to the technical field of high performance liquid chromatography separation. The preparation method of the stationary phase comprises the following steps: preparing carboxyl carbon dots by taking citric acid as a carbon source through a pyrolysis method; the preparation method comprises the following steps: dispersing acidified bare silica gel, polyethyleneimine and carboxyl carbon dots in an ethanol-water solution in proportion to form a uniform system; and then carrying out physical coating through two-step heating reflux under the protection of nitrogen, and finally washing and drying to obtain the product. The complex silica gel alkylation step is omitted, and the process is simple, green and environmentally friendly. The surface of the prepared stationary phase is provided with cation sites provided by polyethyleneimine and anion sites provided by carboxyl carbon dots, so that a multiple hydrophilic and ionic interaction mechanism is formed, and more than thirty polar compounds, including nucleoside / basic groups, sulfanilamide, antibiotics, alkaloids, flavones, amino acids and saccharides, can be subjected to efficient baseline separation; the method has important application value in the fields of drug analysis, environment detection and the like.

The invention relates to the technical field of pharmaceutical analysis, and discloses a method for simultaneously determining the contents of various components in Shuanling antidiarrheal granules based on a UPLC-QQQ-MS / MS. The contents of 18 components in the Shuanling antidiarrheal granules are simultaneously determined by using an ultra-high performance liquid chromatography-tandem triple quadrupole mass spectrometer. The 18 components comprise adenosine, gallic acid, protocatechuic acid, neochlorogenic acid, chlorogenic acid, cryptochlorogenic acid, liquiritin, ellagic acid, kaempferitrin, narirutin, hesperidin, baicalin, oroxylin A-7-O-beta-D-glucuronide, wogonin, baicalein, wogonin, pachymic acid B and pachymic acid A. The invention further discloses a preparation method of the pharmaceutical composition. Through the UPLC-QTRAP-MS / MS combined technology, the technical prejudice that single component depends on in quality control of the traditional Chinese medicine compound preparation is broken through, the key problems that multiple components in a complex matrix are difficult to separate, low-content components are difficult to detect and the like are solved, efficient, accurate and synchronous determination of 18 components is achieved, and the method is suitable for large-scale popularization and application. A new reference path is opened up for modernized quality control of the traditional Chinese medicine compound preparation.

The present application relates to the technical field of pharmaceutical analysis, and in particular to a thin-layer identification method for Qingxiangteng formula granules and standard decoction, which comprises the following steps: subjecting test sample solution and control medicinal material solution to thin-layer chromatography analysis, and comparing the obtained chromatograms, wherein the developing agent is a mixed solution of chloroform, methanol and formic acid in a volume ratio of (5-7):(0.5-2):(0.4-0.6). The present application is simple to operate, free of negative interference, and clear in color development, and is specific and durable, thus being an improvement on the existing Qingxiangteng preparation identification method.

The invention belongs to the technical field of drug analysis, and discloses a method for determining photodegradation impurities in ofloxacin ear drops, which adopts high performance liquid chromatography, takes octadecylsilane chemically bonded silica as a filler, and takes a citric acid solution and acetonitrile as mobile phases to analyze the impurities generated by photodegradation in the ofloxacin ear drops. And measuring the peak area of the impurities in the test solution and the main peak area of the contrast solution by adopting a main component self-contrast method without adding a correction factor, and calculating the content of the impurities. The method can rapidly and accurately analyze ofloxacin photodegradation impurities, is strong in specificity, good in separation degree, stable and reliable, and can realize quality control of ofloxacin ear drops.