84 results about "Reversed-phase chromatography" patented technology

The invention discloses a quantitative detection method for tobacco components. The quantitative detection method comprises the following steps: extracting a tobacco sample to obtain extract liquor; performing component analysis on the extracting solution by adopting high-resolution liquid chromatography-mass spectrometry to obtain a spectrogram of the tobacco sample; the high-resolution liquid chromatography mass spectrometry adopts two ion sources of an ESI source and an APCI source for detection, and the two ion sources both adopt reversed-phase chromatographic columns for detection; in detection, under the ESI source condition, positive and negative ion modes are adopted for scanning respectively, and under the APCI source condition, a positive ion mode is adopted for scanning. According to the quantitative detection method, two different ion sources are adopted, and high coverage and detection precision are both considered; corresponding chromatographic columns are adopted for liquid phase separation, separation of tobacco metabolism components with different properties in a complex natural tobacco matrix is facilitated, and the separation efficiency and the coverage degree are improved; by combining the ultrahigh resolution and high precision of the high-resolution liquid chromatography-mass spectrometry, the to-be-detected substance and the interfering substance are effectively distinguished, and the detection accuracy of various samples is improved.

The invention belongs to the field of biological medicines, and discloses an application of a stem cell extract in preparation of a medicine for treating or preventing arthritis by regulating lysosome and / or mitochondrial function, a preparation method of the stem cell extract comprises the following steps: S1) culturing mesenchymal stem cells and producing stress conditions to stimulate the mesenchymal stem cells; s2) separating and purifying the culture supernatant of the mesenchymal stem cells cultured in the step S1) to obtain a stem cell extract; wherein S21) the culture supernatant is filtered to obtain a filtrate; the preparation method comprises the following steps of (S1) extracting a culture supernatant containing stress stem cell secretions through stress culture of stem cells, (S2) carrying out 3KD ultrafiltration concentration on the filtrate to obtain a crude sample, (S23) purifying the crude sample through molecular sieve exclusion chromatography or reversed-phase chromatography to obtain a purified sample, and (S24) taking the purified sample to form the preparation.

The utility model relates to a two-dimensional liquid phase system which comprises a hydrophilic interaction chromatographic column, a reversed-phase chromatographic column, a detector, an automatic sample injector, a first pump assembly, a second pump assembly, a sample temporary storage unit and a switching valve, the first pump assembly is communicated with the hydrophilic interaction chromatographic column and is used for pushing a sample loading solution and carrying out gradient elution on the hydrophilic interaction chromatographic column; the second pump assembly is communicated with the reversed-phase chromatographic column and is used for carrying out gradient elution on the reversed-phase chromatographic column; wherein the switching valve comprises a first double-four-way valve and a second double-four-way valve which are communicated with each other; the switching valve has at least two connection states through position switching: state 1: the switching valve communicates a liquid inlet of the detector with a liquid outlet of the hydrophilic interaction chromatographic column; and state 2: the switching valve communicates the liquid inlet of the detector with the liquid outlet of the reversed-phase chromatographic column, and communicates the first port of the sample temporary storage unit with the liquid inlet of the hydrophilic interaction chromatographic column. The system can realize one-time analysis of a multi-component target object with relatively large polarity difference.

The invention discloses a high performance liquid chromatography detection method for the content of cibopadol in cibopadol citrate. Chromatographic conditions are as follows: a reversed-phase chromatographic column is adopted, and a phosphate buffer solution and tetrahydrofuran-acetonitrile are taken as mobile phases. By detecting the content of the cibopadol in the cibopadol citrate, the quality of a cibopadol preparation product is favorably controlled, whether the content of the cibopadol meets the requirement or not is judged, and the stability of the cibopadol product is improved. The detection method disclosed by the invention is high in accuracy, good in separation degree, good in stability, simple and convenient to operate, good in repeatability, strong in pertinence and very good in application value.

The invention discloses a separation process of an alpha-glucosidase inhibitor Lycbarbarspermides Q with a new structure in red Chinese wolfberry fruits and application of the alpha-glucosidase inhibitor Lycbarbarspermides Q with the new structure in the red Chinese wolfberry fruits. The specific preparation process comprises the following seven steps: extraction, on-line alpha-glucosidase inhibitor component identification, hydrophilic water pressure preparation column coarse separation, reversed-phase high-pressure preparation column preparation, hydrophilic high-pressure preparation column preparation, gel filtration chromatography and in-vitro alpha-glucosidase inhibition experiment. The method is low in cost, and the product purity is greater than 95%; the technical means adopted by the invention can be used for large-scale production: the raw material requirement is not high, the cost is low, and batch material preparation is easy; in the preparation process, solvents and separation materials used by an extraction solvent, a hydrophilic preparative column, a reversed-phase preparative column, gel chromatography and a reversed-phase chromatographic column can be recycled.

The invention discloses a general secondary amine molecular cage-nanocellulose composite chiral stationary phase for positive and negative phases as well as a preparation method and application of the general secondary amine molecular cage-nanocellulose composite chiral stationary phase. A secondary amine molecular cage (RCC3-R) modified silica gel is used as a substrate, a nano cellulose derivative (NCDMPC) is loaded through a coating method to prepare two chiral stationary phases (CSP-1 and CSP-2), and aminopropyl silica gel is used as a substrate to prepare a control chiral stationary phase (CSP-3). By utilizing the three-dimensional cavity screening effect of RCC3-R and the synergistic effect of an NCDMPC chiral spiral skeleton, the common use of normal phase and reversed phase chromatography modes is realized, and the chiral recognition and separation performance is superior to that of CSP-3. 15 chiral compounds can be split in a normal-phase mode, 12 chiral compounds can be split in a reverse-phase mode, excellent splitting performance on alcohols, amines and chiral drugs is shown, a novel material can be provided for efficient separation of complex systems such as chiral drugs and pesticides, and the application prospect is wide.

The invention discloses a method for improving the detection recovery rate of ascorbyl palmitate in a compound product, which comprises the following steps: taking a sample, adding BHT (butylated hydroxytoluene), then adding an isopropanol-n-hexane mixed solution containing 0.8-1.2% by volume of glacial acetic acid as an extraction solvent, then fully mixing, extracting, freezing, centrifuging, taking supernate, and collecting the supernate to obtain the ascorbyl palmitate. The chromatographic conditions are as follows: a C18 reversed-phase chromatographic column is adopted, a mobile phase A and a mobile phase B are used for gradient elution, the flow velocity of the mobile phase is 0.8-1.2 mL / min, the column temperature is 28-32 DEG C, and the maximum absorption wavelength of ascorbyl palmitate is taken as the detection wavelength. According to the method, the extraction efficiency is improved by optimizing a sample pretreatment process, and the problem that the liquid phase detection error of the substance in the compound product is generally higher than 10% is effectively solved in combination with improved high performance liquid chromatography separation conditions.

The invention relates to the technical field of medicines, and discloses an application of a traditional Chinese medicine composition in serum neurotransmitter, which comprises the following steps: selecting 6-8 weeks old mice to establish a normal model, a chronic fatigue syndrome model and a functional dyspepsia model; the method comprises the following steps: sampling blood from mice of a normal model, a chronic fatigue syndrome model and a functional dyspepsia model to respectively obtain a normal blood sample, a CFS blood sample and an FD blood sample, and performing protein precipitation operation to obtain normal deproteinized supernatant, CFS deproteinized supernatant and FD deproteinized supernatant; separating by using a reversed-phase chromatographic column, and then carrying out mass spectrometric detection to respectively obtain a normal serum neurotransmitter mass spectrogram, a CFS serum neurotransmitter mass spectrogram and an FD serum neurotransmitter mass spectrogram; and carrying out concentration value calculation and rhythm fluctuation analysis to respectively obtain a neurotransmitter function index and a rhythm stability quantitative score. Therefore, the action mechanism of the serum neurotransmitter of the traditional Chinese medicine composition can be clearly and quantitatively represented.

The invention provides a method for detecting a lesinurad derivative U01 and / or related substances thereof, and relates to the technical field of pharmaceutical analysis. According to the method, a high performance liquid chromatography is adopted, a C18 reversed-phase chromatographic column is adopted, a formic acid aqueous solution-acetonitrile is used as a mobile phase system, and a specific gradient elution procedure is adopted; high separation and detection of the lesinurad derivative U01 and intermediates (impurity B and impurity C), enantiomers (impurity D) and side reaction products (impurity E and impurity F) generated in a synthesis process route thereof are realized, and the conditions of related substances can be accurately determined and quantified. The detection method provided by the invention has the advantages of high sensitivity, good specificity, high accuracy, high precision and capability of simply, conveniently, quickly and accurately determining related substances and intermediates, provides a more reliable basis for synthesis process route research and quality control of the Lesinurad derivative U01, and ensures the quality of the Lesinurad derivative U01 product.

The application discloses a lipoic acid high-performance liquid chromatography detection method, which comprises the following steps: S1, sample pretreatment: ultrasonic extraction is carried out on the sample by using a composite extraction liquid, then solid-liquid separation is carried out, and a test sample solution is obtained; the composite extraction liquid is an acetonitrile water mixed solution containing cysteine and EDTA salt; S2, HPLC detection: the chromatographic conditions are as follows: a C18 reversed-phase chromatographic column is used, a buffer solution-alcohol mixed system is used as a mobile phase, the pH of the buffer solution is 2.5-3.5, the detection wavelength is 210-220 nm in the first stage and is 275-285 nm in the second stage, the first stage is 0-7-9 min, and the second stage is 7-9 min-14-16 min. By optimizing the pretreatment method, optimizing the chromatographic conditions and adopting a dynamic detection wavelength, the lipoic acid content detection method with high sensitivity and strong anti-interference ability is obtained.

This invention discloses a purification method for Tirzepatide. The method includes: dissolving crude Tirzepatide peptide in ammonia or sodium bicarbonate solution, filtering, and purifying by reversed-phase chromatography to obtain a purified sample; eluting the purified sample using reversed-phase high-performance liquid chromatography (RP-HPLC) with a sodium or potassium buffer solution as mobile phase A3 and one or a mixture of acetonitrile, methanol, and isopropanol in any proportion as mobile phase B, preparing a sodium or potassium salt fraction; cooling the sodium or potassium salt fraction to -20 to 10°C and maintaining the temperature; then adding an organic solvent to the fraction, controlling the temperature at -20 to 10°C to precipitate the sample; after complete precipitation, solid-liquid separation is performed, the solid is collected, dissolved in water, filtered, and freeze-dried. This invention improves the concentration speed, ensures product purity, and strictly controls impurities.

The invention relates to the technical field of polypeptide medicine purification, in particular to a purification method of retaglutide. The method comprises the following steps: mixing a retaglutide crude product aqueous solution with salt to enable the final concentration of the salt to be 0.5-2.0 mol / L, and loading a sample to a chromatographic column filled with a hydrophobic interaction chromatographic filler; eluting by adopting a salt concentration decreasing gradient, and collecting to obtain a first purified solution; adjusting the pH and conductivity of the first purified liquid, and loading the first purified liquid to a chromatographic column filled with an ion exchange chromatographic filler; eluting by adopting a gradient of increasing salt concentration, and collecting to obtain a second purified solution; and loading the second purified solution to a chromatographic column filled with a reversed-phase chromatographic filler, taking an acidic modifier aqueous solution as a mobile phase A and an organic solvent as a mobile phase B, eluting by adopting a gradient of increasing concentration of the organic solvent, and collecting to obtain a final product. Through innovative process combination, the problems that in the prior art, impurities are difficult to deeply remove, and the consumption of an organic solvent is large are effectively solved.

The application provides a method for determining the content of biotin in a complex vitamin preparation. The method comprises detecting the content of biotin by high performance liquid chromatography, wherein a surface porous reversed-phase chromatographic column with modified amide groups is used for gradient elution, and a mobile phase A and a mobile phase B are used, the mobile phase A comprises potassium dihydrogen phosphate buffer and acetonitrile, and the mobile phase B comprises acetonitrile. The method can realize the non-interference separation and detection of the content of biotin in the complex vitamin preparation with a complex matrix, and has the advantages of simplicity, good specificity, rapid analysis, accurate result and sensitive response.

This invention provides a method for purifying high-purity recombinant follicle-stimulating hormone (FSH). Specifically, it includes the following steps: (a) providing a raw material solution containing recombinant FSH; (b) sequentially subjecting the raw material solution to: (b1) ammonium sulfate precipitation; (b2) hydrophobic interaction chromatography (HIC); (b3) low pH incubation to inactivate the virus; and (b4) reversed-phase chromatography (RPC); wherein steps (b1), (b2), (b3), and (b4) cannot be performed in any arbitrary order. Compared with existing preparation methods, the recombinant FSH obtained by the method of this invention is simpler and easier to operate, and the purity of the recombinant FSH obtained by the method of this invention can reach up to 99.5% w / w, with a specific activity as high as 16000 IU / mg.

The application discloses a multi-component joint detection method, device and application for synchronous analysis of bone metabolism markers. The multi-component joint detection method comprises the following steps: pretreating a serum sample, and simultaneously extracting small molecule sterols, short peptides and protein characteristic peptide segments; adopting a reverse phase chromatography system to perform chromatographic separation on the extracts, and realizing synchronous elution of lipid-soluble substances and polar substances through a variable gradient elution program; and adopting a segmented multi-reaction monitoring mode to perform mass spectrometry detection, and simultaneously detecting high-abundance indexes and low-abundance indexes in bone metabolism markers in a same sampling period. The application realizes synchronous quantitative detection of five bone metabolism markers, solves technical problems such as fragmentation, large concentration span, incompatible chromatographic behavior and isomer interference in the prior art, and improves detection efficiency by more than 400%, and reduces detection cost by 50%-70%.

The invention belongs to the technical field of health, clinical and medical related detection, and relates to a liquid chromatography-mass spectrometry detection kit and a detection method for serum seleno-amino acid labeled on the basis of a mass spectrometry probe. The detection kit comprises a mass spectrum probe solution, a protein precipitant solution and a buffering agent solution, the mass spectrum probe is 6-aminoquinolyl-N-hydroxysuccinimido carbamic acid ester, and the mass spectrum probe is 2-aminoquinolyl-N- The buffer solution contains a seleno-amino acid isotope internal standard. According to the kit, a mass spectrum probe is used for labeling, a serum sample is subjected to protein precipitation and then mixed with the mass spectrum probe at room temperature, and simultaneous high-flux accurate quantification of multiple seleno-amino acids can be directly achieved through liquid chromatography-tandem mass spectrometry in a conventional reversed-phase chromatography mode. The 6-aminoquinolyl-N-hydroxysuccinimido carbamate mass spectrum probe adopted in the kit disclosed by the invention has the advantages of high reaction activity, convenience in operation, high sensitivity and the like.

The invention belongs to the field of analytical chemistry and food safety detection, and discloses a fish oil plasticizer liquid chromatography-tandem mass spectrometry detection method, which is characterized in that a target molecule is structurally modified through a specific chemical derivatization reagent, and the electrospray ionization efficiency is remarkably improved, so that a mass spectrometry response signal is enhanced; solid-phase extraction purification and high-performance reversed-phase chromatography separation are combined, so that effective removal of matrix interference and synchronous detection of various plasticizers are realized; the method does not need a complex solvent system, and is simple in operation flow and good in reproducibility; the detection limit reaches ppb level, the linear range is wide, the method is suitable for conventional and high-throughput detection of the plasticizer in fish oil and fish oil products, and a sensitive and reliable analysis tool is provided for quality safety assessment of related products.

The invention discloses a high performance liquid chromatography (HPLC) detection method for enantiomers in moxifloxacin hydrochloride with high separation degree, and belongs to the technical field of medicine detection. The method aims at solving the problems that in the prior art, the leading edge of a main component peak is serious, and the detection accuracy and good peak pattern under the conditions of high separation degree and low content are difficult to meet at the same time, and the adoption of an expensive chiral chromatographic column is avoided. According to the detection method, chiral resolution is realized on a conventional high performance liquid chromatograph by adopting a reversed-phase chromatographic column (such as terminated octadecylsilane chemically bonded silica as a filler). According to the core technical scheme, the unique mobile phase composition is as follows: a water phase contains 0.54 g / L of zinc acetate and 1.17 g / L of L-valine, 1ml of diethylamine is creatively added, and the pH value is adjusted to 5.6 by using dilute sulfuric acid; and an organic phase adopts a methanol-ethanol mixed solution (15: 8) with a specific ratio. And finally, mixing the water phase and the organic phase according to the volume ratio of 77: 23. Under optimal chromatographic conditions (the column temperature is 40 DEG C and the detection wavelength is 295 nm), the method can realize efficient separation between moxifloxacin hydrochloride and enantiomers, the separation degree is greater than 4.5, and the detection accuracy of trace isomers can be realized. A methodological verification result shows that the method is high in sensitivity (the detection limit is 0.0096%, and the quantitation limit is 0.024%), and has a good linear relationship (a correlation coefficient rgt; and the accuracy is good (the recovery rate is between 80.0% and 120.0%). The method can be used for qualitative and quantitative analysis of the moxifloxacin hydrochloride bulk drug and enantiomers in the moxifloxacin hydrochloride preparation.

The present application belongs to the field of biopharmaceuticals. Disclosed is the use of a stem cell extract in the preparation of a drug for treating or preventing arthritis by regulating lysosomal and / or mitochondrial functions, wherein a method for preparing the stem cell extract comprises: S1) culturing mesenchymal stem cells and creating stress conditions to stimulate the mesenchymal stem cells; and S2) isolating and purifying a culture supernatant of the mesenchymal stem cells cultured in S1) to obtain a stem cell extract, wherein S2) comprises: S21) filtering the culture supernatant to obtain a filtrate; S22) concentrating the filtrate by means of 3KD ultrafiltration to obtain a crude sample; S23) purifying the crude sample by means of size-exclusion chromatography or reversed-phase chromatography to prepare a purified sample; and S24) preparing the purified sample into a preparation. In the present application, the culture supernatant containing secretions of the stressed stem cells is obtained by means of stress culturing of the stem cells, and in combination with a purification method, the supernatant is prepared into a preparation which can be used for treating arthritis.

The invention belongs to the technical field of analytical chemistry and medicinal chemistry, and particularly discloses a sucrose octasulfate separation and detection method based on high performance liquid chromatography. According to the method, a to-be-treated solution containing sucrose octasulfate is subjected to high performance liquid chromatography separation, and a detector is arranged for detection after high performance liquid chromatography separation to obtain the content of sucrose octasulfate; chromatographic conditions are as follows: a chromatographic column is a reversed-phase chromatographic column; the gradient elution procedure is carried out for 0-12 min, the ratio of a mobile phase A to a mobile phase B is 95: 5, 12-30 min, and the B is linearly increased to 20%; the linear recovery to the initial condition is carried out in 30-30.1 min, and the A: B = 95: 5 in 30.1-35 min; the column temperature is 35-37 DEG C; and direct amplification is carried out for preparative chromatography, so that separation and preparation of sucrose octasulfate can be realized. The separation or detection method disclosed by the invention has good separation degree, sensitivity and universality, and is high in analysis speed, good in repeatability and wide in application.

The invention relates to a method for purifying a non-steroidal GnRH agonist polypeptide, in particular to a method, a system and a product for preparing water-soluble high-purity delorelin acetate. According to the invention, a raw material medicine existing in a high acetate form is obtained through preparative-grade reversed-phase chromatography purification, ion conversion on a column and optimization of salt conversion and freeze-drying pretreatment. The HPLC purity of the product is greater than or equal to 98.5%, the acetic acid content is about 13.9%-14.7% (w / w), the solubility in pure water is greater than or equal to 120 mg / mL, and the product is kept clear for 24 hours; the retention time is consistent with that of a commercial reference substance. And compared with a contrast, the method has the advantages that the high-purity fraction yield is obviously improved, impurities and non-target pair ion residues are reduced, and the method is suitable for industrial amplification and preparation development.

The invention discloses an extraction method of oat polypeptide, and belongs to the technical field of polypeptide extraction. The method comprises the following steps: carrying out enzymolysis on an oat protein raw material to obtain a crude extract; carrying out oscillation adsorption on the crude extract by using a modified graphene material to enrich polypeptide; then desorbing to obtain a preliminarily enriched polypeptide solution; carrying out gradient elution by using a reversed-phase C18 chromatographic column, and carrying out fine separation; and finally, concentrating and drying to obtain a high-purity oat polypeptide product. The key preparation method of the modified graphene comprises the following steps: by taking an oat processing byproduct as a raw material, preparing sulfonic acid group carbon dots through a concentrated sulfuric acid hydrothermal method, and then grafting the sulfonic acid group carbon dots and graphene oxide through electrostatic self-assembly and hydrothermal reaction to obtain a three-dimensional network structure material with the surface rich in sulfonic acid groups. According to the method, the homologous modified material is used for enhancing specific adsorption, chromatographic refining is combined, the oat polypeptide is purified from the complex enzymatic hydrolysate in a high-efficiency, high-selectivity and low-cost mode, the process is green and environmentally friendly, and the obtained product is high in purity and good in biological activity.

The invention relates to the technical field of separation and purification of active ingredients of traditional Chinese medicines, and discloses a saponin compound derived from aralia elata and a preparation method thereof. The saponin compound has a structure as shown in a formula (I). The preparation method comprises the following steps: carrying out hydrous ethanol extraction on aralia mandshurica root bark, enriching through macroporous adsorption resin, carrying out directional enrichment on acidic saponin through anion exchange resin, carrying out coarse separation and preparative liquid phase refining by adopting reversed-phase C18 chromatography, and carrying out window collection in combination with online detection to obtain a target saponin compound. The method can improve the separation selectivity of the target component, reduce the co-elution phenomenon and improve the purity and batch stability of the final product, and is suitable for preparation of the aralia mandshurica sourced saponin compound.

The application relates to the technical field of medicines, and discloses application of a traditional Chinese medicine composition in serum neurotransmitters, which comprises the following steps: selecting 6-8-week-old mice to establish normal models, chronic fatigue syndrome models and functional dyspepsia models; blood sampling is conducted on the mice of the normal models, the chronic fatigue syndrome models and the functional dyspepsia models to obtain normal blood samples, CFS blood samples and FD blood samples respectively; protein precipitation operation is conducted to obtain normal deproteinized supernatants, CFS deproteinized supernatants and FD deproteinized supernatants; separation is conducted by using a reversed-phase chromatographic column, and then mass spectrometry is conducted to obtain normal serum neurotransmitter mass spectra, CFS serum neurotransmitter mass spectra and FD serum neurotransmitter mass spectra respectively; concentration value calculation and rhythm fluctuation analysis are conducted to obtain a neurotransmitter function index and rhythm stability quantitative score respectively. Therefore, the mechanism of the traditional Chinese medicine composition in serum neurotransmitters is clearly quantitatively characterized.

The invention provides a method for detecting the content of urea in a water sample by using high performance liquid chromatography. The method comprises the following steps: preparing a urea standard solution; performing filter membrane filtration pretreatment on the to-be-detected water sample; carrying out high performance liquid chromatography analysis according to optimized chromatographic conditions, and calculating the urea content by adopting a standard curve method; wherein the chromatographic conditions are as follows: a C18 type reversed-phase chromatographic column is adopted, a mixed solution of acetonitrile and ultrapure water is adopted as a mobile phase, isocratic elution is performed, and the detection wavelength is 190-200nm. According to the method, the mobile phase and the chromatographic column are improved, the urea content in the water sample is directly and accurately detected, operation is easy and convenient, the detection time is short, good specificity and stability are achieved, the detection limit is lower than 0.6 microgram / L, the recovery rate ranges from 95% to 105%, the relative standard deviation is smaller than 2%, and the method can be effectively applied to detection and analysis of the urea content in various environment water samples.

The application discloses a method for simultaneously detecting retinoids and lipid-soluble vitamin metabolic marker groups in biological samples and matching reagents. The application is based on magnetic bead solid-phase extraction technology, significantly improves sample purification effect, and reduces matrix interference; in combination with a high-aqueous-phase reversed-phase chromatography system and a positive-negative ion switching multi-reaction monitoring mode, simultaneous separation and detection of seven retinoid molecules and a full spectrum of lipid-soluble vitamins are realized. The method has high sensitivity, strong specificity and wide detection range, and for the first time realizes one-stop analysis across species and sample types, thereby providing reliable platform support for clinical and scientific research applications.

The present invention provides a method for analyzing a peptide compound in a sample and an oligomer derived from said peptide compound, said method comprising using a reversed-phase column to perform liquid chromatography in which a solvent containing a C2-3 alcohol is used an eluent.

The invention discloses a detection and analysis method for an alpoxivan intermediate 3 and related impurities, and relates to the field of substance detection methods, the detection and analysis method comprises the following steps: S1, preparation of a test solution: taking a sample, adding a solvent into the sample, dissolving, and diluting for later use; s2, setting chromatographic conditions and a gradient elution program, wherein the chromatographic conditions of the chromatography comprise the use of a reversed-phase C18 chromatographic column, a mobile phase A and a mobile phase B; s3, taking the test solution, injecting the test solution into a liquid chromatograph, recording a chromatogram, and calculating the impurity content; wherein the mobile phase A is prepared from 0.15 to 0.25 weight percent of triethylamine solution, and the pH (Potential of Hydrogen) of the mobile phase A is 2 to 3; the mobile phase B comprises methanol. According to the method disclosed by the invention, the aim of effectively separating and quantifying various related impurities of the alpoxivan intermediate 3 is fulfilled through optimized chromatographic conditions.

The present application belongs to the field of fingerprint, and particularly relates to a method for detecting medicinal stems of Dendrobium candidum from Sichuan origin. The specific technical scheme is as follows: a method for constructing a Dendrobium fingerprint, comprising the following steps: mixing a Dendrobium powder to be tested with methanol, performing ultrasonic treatment, taking out, cooling, and filtering; evaporating the filtrate under reduced pressure, dissolving the residue with methanol, filtering, shaking, and obtaining a test solution; taking the test solution, performing high performance liquid chromatography detection, and recording a fingerprint; and the chromatography detection has the following chromatography conditions: a C 18 reverse-phase chromatography column; a column temperature of 30 DEG C; a detection wavelength of 270 nm; and a total flow rate of 0.8 mL / min. The method provided by the present application is simple to operate, has complete characteristic components, and has a stable test solution, high precision, and good reproducibility.

This invention belongs to the field of chromatographic detection and analysis, and discloses a reversed-phase chromatographic analysis method for the purity of enterokinase protein. High-performance liquid chromatography (HPLC) is used to detect enterokinase in the sample solution. In this HPLC method, the chromatographic column is selected from reversed-phase chromatographic packing material C18 or C8, with a particle size of 3.5~5 μm and a pore size of 120~1000 Å. The mobile phase is selected as follows: an aqueous solution of heptafluorobutyric acid (HFA) is used as mobile phase A, and an acetonitrile solution of HFA is used as mobile phase B. This invention improves the separation of the main peak and subsequent impurities in the enterokinase stock solution by screening suitable mobile phase systems and column types. It also optimizes chromatographic parameters such as the proportion of modifier in the mobile phase, column temperature, sample loading, mobile phase gradient, and wavelength, ultimately achieving effective separation of the main peak and subsequent impurities in the enterokinase stock solution. Furthermore, the analysis time is short and the repeatability is good, providing an effective analytical method for the quality control of enterokinase stock solution.