ArchiveGas chromatography-Orbitrap mass spectrometry (GC-Orbitrap/MS), a developing gas chromatography-high resolution mass spectrometry approach, allows for high throughput qualitative and quantitative analysis of volatile and semi-volatile components. It has the advantages of high sensitivity, selectivity, and a wide linear dynamic range, which makes it well suitable for the analysis of a wide range of trace substances in complex matrices. In recent years, this technology has been applied in environmental science, industry, food analysis, pharmaceutical analysis, forensic science, clinical medicine and other fields. This paper presents the first review of GC-Orbitrap/MS, which not only describes the basic principles and technical characteristics, but also introduces the progress of the technique in food and pharmaceutical research. Applications in food analysis include the inspection of pesticide residues, detection of persistent organic compounds and analysis of flavor substances. In pharmaceutics, the analysis of chemical impurities and quality evaluation of traditional Chinese medicine are introduced. It is noteworthy that this technique is particularly advantageous for the identification of unknown compounds and the determination of ultra-trace components. Lastly but importantly, this review summarizes the challenges encountered in the current development of this technique, including the establishment of high-resolution standard databases, the selection and optimization of sample pre-treatment method and the application of GC-Orbitrap/MS in the field of traditional traditional Chinese medicine. A few solutions are also proposed, such as the application of variable electron voltage technique, the combination of two-dimensional gas chromatography and electrostatic field Orbitrap mass spectrometry and the integrated analysis comprehensively using multiple scan modes. These strategies are aimed to provide more advanced and accurate solutions to food, pharmaceutical, and other relevant analysis.
Patch refers to a thin sheet flexible preparation made of raw drug and suitable material for sticking on the skin, which can produce systemic or local effects. In vitro release test (IVRT) and in vitro permeation test (IVPT) are important contents of preclinical pharmaceutical research for formulation process optimization, quality control and safety and effectiveness evaluation of patch. The experimental equipment and methods used are different, the obtained experimental samples and data are different from each other, and the accuracy and precision of the experimental data are also different. Therefore, the selection of experimental equipment and the establishment of experimental methods in the in vitro experiment of IVRT & IVPT is a problem worthy of attention. In this paper, the research status of patch was summarized, the requirements of pharmacopoeia of different countries for IVRT experiments were briefly introduced, and the differences of different methods were reviewed. For IVPT experiments that have not yet been prescribed by relevant standards, the common types of experimental equipment and experimental conditions were introduced in detail, the applicability of different equipment and the influence of main experimental conditions (temperature, stirring speed, composition of acceptor solution, selected skin, etc.) on the experimental results were summarized, and the research progress of in vivo and in vitro correlation was introduced. At the same time, the validity of the experimental data was discussed, hoping to provide a useful reference for the development and research of the in vitro experimental methodology of the patch.
To analyze the chemical constituents of Quyusanjie capsules by LC/MS, and establish a method for the determination of active ingredients in Quyusanjie capsules.
Using UPLC-Q TOF MS/MS technology, the Hypersil Gold C18 column(100 mm×2.1 mm, 1.9 μm) was used, the mobile phase was acetonitrile(A) and 0.1% formic acid in water(B) with gradient elution, at a flow rate of 0.4 mL·min-1, the the column temperature was 40.0 ℃, and the mass spectrometry data was collected by negative ions mode scanning. Through database matching, elemental composition and fragment structure analysis, the main chemical substances in Quyusanjie capsules were identified. HPLC was used to qualitatively analyze the chemical components of Quyusanjie capsules. The Ultimate® AQ-C18 column(250 mm×4.6 mm, 5 μm) was used, the mobile phase was acetonitrile(A) -0.1% phosphoric acid(B) with gradient elution at the flow rate of 1.0 mL·min-1, the column temperature was 25 ℃, and the detection wavelength was 203 nm. The content of naringin, neohesperidin, notoginsenoside R1, ginsenoside Rg1, and ginsenoside Rb1 in 11 different batches of Quyusanjie capsules were determined using external standard method. QAMS method was established using ginsenoside Rg1 as the internal reference.
Twenty-nine compounds were identified from Quyusanjie capsule. The contents of naringin, neohesperidin, notoginsenoside R1, ginsenoside Rg1 and ginsenoside Rb1 measured by external standard method were 0.484-1.097 mg·g-1, 0.341-0.618 mg·g-1, 1.685-2.399 mg·g-1, 5.748-8.386 mg·g-1, 3.868-5.898 mg·g -1, respectively. Measured with the QAMS method, the contents of naringin, neohesperidin, notoginsenoside R1 and ginsenoside Rb1 were 0.516-1.153 mg·g-1, 0.372-0.667 mg·g-1, 1.794-2.580 mg·g-1, 4.373-6.690 mg·g-1, respectively. The relative error between the calculated values of the QAMS method and the measured value of the external standard method was less than 8.9%.
UPLC-Q TOF MS/MS method can quickly identify the chemical components of Quyusanjie capsules. The established external standard method is stable and reliable, and can be used for the quality control of Quyusanjie capsules. The method of QAMS has good feasibility and is suitable for the determination of the daily production of Quyusanjie capsules.
To predict potential quality markers(Q-Marker) of Taxus media Rehd. based on fingerprint and network pharmacology methods, and establish an evaluation method of Taxus media Rehd. based on Q-Marker, as so to provide basis for the establishment of quality standard and quality evaluation system of Taxus media Rehd..
Waters SymmmetryShieldTM RP18(250 mm×4.6 mm, 5 μm) chromatographic column was used for separation, and the wavelength was 254 nm. The mobile phase was acetonitrile -0.01% trifluoroacetic acid aqueous solution for gradient elution at a flow rate of 1.0 mL·min-1, and the column temperature was 30 ℃. The injection volume was 10 μL. The fingerprints of 24 batches of Taxus media Rehd. with 8 kinds of cultivation years were established and the common peaks were identified. Hierarchical clustering analysis (HCA) was used for classification, orthogonal partial least square-discriminant analysis (OPLS-DA) was used to screen out the main marker components that cause differences between different years. Combined with network pharmacology, the core targets and key pathways were constructed a “component-target-pathway” network map through corresponding databases. Q-Markers were further verified and quality of Taxus media Rehd. comprehensively evaluated by HCA and PCA.
A total of 25 common peaks were obtained in the HPLC fingerprint of Taxus media Rehd., 18 compounds were identified, and their similarities were all above 0.900, including taxanes, flavonoids, alkaloids, steroids and phenols. The results of HCA showed that there were some differences among samples with different cultivation years. Eleven different markers were screened by OPLS-DA, and they were paclitaxel, 10-deacetylbaccatin Ⅲ (10-DAB), baccatin Ⅲ, cephalomannine, deacetyltaxol (10-DAT), ferulic acid, kaempferide, rutin, amentoflavone-4’, 4", 7-trimethyl ether, skyrin, 4-hydroxybenzaldehyde. Based on the difference markers, network pharmacology was applied to analyze them from the perspective of effectiveness. Paclitaxel, 10-DAB, bakatine Ⅲ, cephalomannine and 10-DAT were preliminstly predicted as Q-Markers of Taxus media Rehd.. They could regulate cancer pathway, AGE-RAGE signaling pathway in diabetic complications and other signaling pathways by PIK3R1, AKT1, EGFR, HRAS and MAPK1 targets, and play the role of reducing swelling and menstruation diuresis clearing. The results of HCA verified the rationality of Q-Marker, and the comprehensive evaluation results of PCA showed that sample which was cultivated for ten years and harvested in spring bore the best quality.
Paclitaxel, 10-DAB, bakatine Ⅲ, cephalomannine and 10-DAT are selected as Q-Markers based on fingerprint and network pharmacological methods. The quality of Taxus media Rehd. in different cultivation years is sorted comprehensively by combining with chemical recognition pattern method. The 10-year-old sample harvested in spring gets the highest score and the quality is good. The study provides new method for establishing of quality standard and the quality evaluation of Taxus media Rehd..
To prepare and investigate the content determination of Nocardia rubra cell wall skeleton (N-CWS) loading film.
Taking chitosan and polyvinyl alcohol as film-forming materials, N-CWS film was prepared by solution casting method. The film was characterized by scanning electron microscopy(SEM), Fourier transform infrared spectroscopy(FTIR) and universal tensile testing machine. Determination of arabinose in N-CWS film was carried out by HPLC. The Kromasil C18 column(150 mm×4.6 mm, 5 μm) was adopted, with the elution of 50 mmol·L-1 phosphate buffer (pH 7.0)-acetonitrile (80∶20, v/v). The flow rate was 1.0 mL·min-1, the detection wavelength was 254 nm, and the column temperature was 40 ℃.
When the mass ratio of chitosan to polyvinyl alcohol was 3∶2 and the mass ratio of membrane material to glycerol was 1∶2, the tensile modulus reached 2.47 mPa and the tensile strain at break was 136.67%. Scanning electron microscopy showed that N-CWS was distributed asymmetrically on the bottom of the film. The linear relationship of D-arabinose in the prepared film was good in the range of 1.1-220 μg·mL-1, and the average recovery rate was 99.5%. The determination results of three batchs N-CWS films showed that the contents of D-arabinose in the films were (0.988±0.041) mg·g-1, (1.035±0.049) mg·g-1, (1.088±0.046) mg·g-1, respectively.
The preparation process of N-CWS loading film is simple and feasible, and the content determination method is accurate and fast. This study can provide reference for the development of new dosage forms of N-CWS.
To establish a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the simultaneous determination of atorvastatin, two activity-related hydroxy statin metabolites and three toxicity-related statin lactones in human plasma, and its application to the study of pharmacokinetics in healthy subjects and the analysis of concentrations in patients.
After acidification, plasma samples were treated by protein precipitation. The LC separation was performed on a Zorbarx SB-C18(50 mm×2.1 mm, 5 μm) column. Methanol-acetonitrile (1∶1) water-methanol-acetonitrile (9∶0.5∶0.5) containing 0.05% formic acid were used as the mobile phases for gradient elution, and the flow rate was 0.35 mL·min-1. The electric spray ionization source, positive ion mode and multi-reaction monitoring scanning were adopted for MS detection. The m/z of each targeted analyte was 559.3→440.2 for atorvastatin, 575.1→440.3 for 2-hydroxy atorvastatin acid (2-HAT) and 4-hydroxy atorvastatin acid (4-HAT), 540.9→448.2 for atorvastatin lactone (ATL), 557.2→448.2 for 2-hydroxy atorvastatin lactone (2-HATL) and 4-hydroxy atorvastatin lactone (4-HATL), and 422.2→290.0 for the internal standard of pitavastatin. After a full method validation, the developed LC-MS/MS method was used to determine the plasma samples of healthy subjects and patients after taking atorvastatin calcium tablets, and the pharmacokinetic characteristics of atorvastatin and five metabolites were analyzed.
The calibration curves of atorvastatin and its metabolites presented a good linear relationship in the range of 0.1-25 nmol·L-1. The RSD of intra-and inter-day precision and the RE of accuracy were all less than 15%, and the stability was well tolerated under different conditions. In healthy subjects after oral administration of 20 mg atorvastatin calcium tablets, the respective mean values of Cmax for atorvastatin, 2-HAT, 4-HAT, ATL, 2-HATL and 4-HATL were 11.48, 4.71, 0.28, 1.71, 2.52 and 2.31 nmol·L-1, AUC0-∞ were 87.31, 58.79, 8.60, 28.75, 45.76, 31.49 nmol·h·L-1, t1/2 were 7.96, 7.93, 19.58, 8.76, 8.98 and 21.37 h. After 12 h of administration, the average blood concentrations of atorvastatin, 2-HAT, 4-HAT, ATL, 2-HATL and 4-HATL in the patient were (4.16±1.31) nmol·L-1, (2.65±1.33) nmol·L-1, (1.15±1.16) nmol·L-1, (2.96±1.83) nmol·L-1, (4.27±2.00) nmol·L-1 and (3.70±1.74) nmol·L-1.
The method for the simultaneous quantitative determination of atorvastatin and five metabolites in human plasma established in this study is accurate, rapid, sensitive and stable, and can be used for clinical pharmacokinetics research and plasma drug concentration monitoring. The clinical studies revealed that toxicity related lactone metabolites have a high level of exposure in humans, which requires attention to the possible risk of side effects.
To develop a high performance liquid chromatography-mass spectrometry (HPLC-MS/MS) method for the determination of vildagliptin in human anticoagulant plasma with ethylenediamine tetra acetic acid and apply it to the study of pharmacokinetics.
13C-15N-vildagliptin was used as internal standard (IS). After extraction from human plasma by protein precipitation with acetonitrile, all components were separated by a Hypurity C18 column (150 mm×2.1 mm, 5 μm), using a gradient elution procedure consisting of methanol and 5 mmol·L-1 ammonium formate at a flow rate of 0.5 mL·min-1, and the column temperature was 40 ℃. Injection volume was just 2 μL. Positive electrospray ionization was performed using multiple reaction monitoring (MRM) with transitions of m/z 304.3→154.2 for vildagliptin and m/z 310.3→160.3 for internal standard. Specificity, standard curve, lower limit of quantification, precision, recovery, matrix effect and stability were examined. Then this method was used to determine the plasma concentration of veragliptin in healthy subjects.
The calibration curve of vildagliptin in human plasma was linear over the concentration range of 1.11 to 534.0 ng·mL-1. The lower limit of quantitation was 1.11 ng·mL-1. The intra-and inter-day precisions at four quality control levels were within 0.9%-8.5%, and the accuracy was within 99.8%-109.3%. The data of short-term stability at room temperature displayed that the accuracy percentage of LQC samples was 92.0% for 0.5 h exposure, 87.6% for 1 h exposure, 71.2% for 2 h exposure. These of LQC samples chilled on ice was 102.0% for 0.5 h exposure, 94.5% for 1 h exposure, 86.6% for 2 h exposure. These results showed a phenomenon that there was a possible degradation of vildagliptin in plasma. The results of extraction recovery and matrix effect and other stability met the requirements of biological sample analysis. The pharmacokinetic study results of 8 healthy subjects showed that t1/2 was (1.49±0.37) h, tmax was (2.06±1.11) h, Cmax was (290.94±100.36) ng·mL-1, AUC0-24 h was (1 343.46±186.89) ng·h·mL-1, AUC0-∞ was (1 351.31±188.79) ng·h·mL-1.
This method is easy to operate, has high specificity, and sensitivity. It has been successfully applied to the pharmacokinetic study of 8 healthy subjects after oral administration of 50 mg vigagliptin tablets on an empty stomach. Therefore, it can be used as a reliable detection method for human pharmacokinetic research and therapeutic drug monitoring.
To establish an LC-MS/MS method for the determination of the abundance data of dexamethasone-related metabolic enzymes and transporters in the placenta of Chinese pregnant women.
A Shim-pack GISS-HP C18 (100 mm×2.1 mm, 1.9 μm) chromatographic column was used, and the mobile phases were consisted of 0.2% formic acid-water (phase A) and 0.2% formic acid-acetonitrile (phase B) with gradient elution at a flow rate of 0.2 mL·min-1. The post-column phase C consisted of 0.5% ethylene glycol-acetonitrile was added at a flow rate of 0.1 mL·min-1, and the ESI source positive ion MRM mode was used for quantitative analysis. The established method was investigated methodologically and the expression levels of 11β hydroxysteroid dehydrogenase 1(11β-HSD1), 11β hydroxysteroid dehydrogenase 2(11β-HSD2), cytochrome P450 3A4 enzyme (CYP3A4) and P-glycoprotein protein (P-gp) were quantitatively analyzed in the placenta of Chinese pregnant women in the third trimester.
The established LC-MS/MS method had a linear range of 0.1-100 nmol·L-1(r >0.999). The precision and accuracy results met the requirements of the biological sample analysis method verification in Chinese Pharmacopoeia (RSD≤15%), and the stability results showed that the samples were stability. The protein abundance of 11β-HSD2, 11β-HSD1, CYP3A4 and P-gp were (84.46±59.97) pmol·g-1, (11.44±3.73) pmol·g-1, (8.83±2.78) pmol·g-1 and (7.94±4.10) pmol·g-1, respectively. Besides, the results of the study also showed that there was no significant difference in the distribution of related metabolic enzymes and transporters in different parts of the placenta. However, there was a significant difference in the abundance of P-gp in the placenta between Chinese people (7.94±4.10) pmol·g-1 and white people (4.41±2.46) pmol·g-1.
The LC-MS/MS method established in this study has high accuracy and sensitivity and is suitable for detecting the abundance values of dexamethasone-related metabolic enzymes and transporters in human placenta.
To identify the structures of the related substances in penciclovir cream by two-dimensional liquid chromatography quadrupole time-of-flight tandem mass spectrometry (2D-LC-Q TOF/MS) technique.
The first-dimension separation of the related substances in penciclovir cream and its stressed samples according to ICH were carried out on an ODS (250 mm×4.6 mm, 5 μm) column with gradient elution by 0.15% formic acid 10 mmol·L-1 ammonium formate buffer solution and acetonitrile as mobile phases, and each related substance was enriched separately. The second-dimension gradient elution was performed on a Phenomenex Luna SCX (250 mm×4.6 mm, 5 μm) column with 0.1% formic acid 20 mmol·L-1 ammonium formate buffer solution and acetonitrile as mobile phases for each of the related substances to achieve good separation with the matrix of penciclovir cream. The accurate mass and elemental composition of the parent ions and their product ions of the related substances were determined by positive electrospray-ionization quadrupole time-of-flight high resolution mass spectrometry, and the structures of all the related substances were elucidated.
Under the established 2D-LC-Q TOF/MS analytical conditions, penciclovir and its related substances were adequately separated, and 21 major related substances were detected and identified in the penciclovir cream and its stressed samples. According to their chromatographic retention behavior, spectral characteristics, mass spectrometry characteristics and their differences from other known related substances of nucleoside drugs and combing with synthesis and formulation process route, their structures can be identified all of which were identified for the first time.
The results can provide reference for the quality control of penciclovir cream.
To establish an HPLC-MS/MS method for the determination of the genotoxic impurities (S)-5-chloro-N-(3-chloro-2-hydroxypropyl) thiophene-2-amide and 4-(3-oxy-4-morpholine) nitrobenzene in rivaroxaban. The factors affecting impurities separation and the response of mass spectrometry were systematically investigated.
A ZORBAX SB-C18 column(150 mm×2.1 mm, 3.5 μm) was used with 10 mmol·L-1 ammonium formate solution-methanol as mobile phase at flow rate of 0.4 mL·min-1. And MRM detection by electrospray positive ionization was used.
(S)-5-chloro-N-(3-chloro-2-hydroxypropyl) thiophene-2-amide and 4-(3-oxy-4-morpholine) nitrobenzene had good linear relationships in the range of 0.008-3.4 ng·mL-1 and 0.2-3.4 ng·mL-1, respectively. The average recoveries(n=9) were 97.9% and 98.9%, RSD were 0.94% and 0.68% respectively. The limits of quantitation were 0.008 ng·mL-1 and 0.2 ng·mL-1 respectively. The results of genotoxic impurity residue determination in 15 batches of rivaroxaban samples were far below the limit value.
The method is sensitive and specific, and can effectively detect trace genotoxic impurities in rivaroxaban.
To establish a method for the detection of genetic impurity chloropropanol in hydroxypropyl distarch phosphate (HPDSP).
The method was performed with Agilent VF-WAX capillary column and temperature programmed by GC-MS. The initial temperature was 80 ℃ for 8 min, then increased to 220 ℃ at the rate of 35 ℃·min-1 and maintained for 5 min with the flow rate of 2 mL·min-1. The temperature of inlet was 200 ℃, and the injection volume was 1 μL without split. The detector was electron impact (EI) with selected ion monitoring (SIM) mode and ion source temperature at 230 ℃. The m/z of qualitative ions of 1-chloro-2-propanol were 45, 43, 79, 81, and the m/z of quantitative ion was 79. The m/z of qualitative ions of 2-chloro-1-propanol were m/z 58, 62, 63, 64, 65, and m/z of the quantitative ion was 62.
Good linear was achieved in the range of 20.04 ng·mL-1 to 1 002 ng·mL-1 (r=0.999 8, n=7) and the recovery rate ranged from 93.7% to 117.1% for 1-chloro-2-propanol. The contents of chloropropanol in 9 batches were within the range of 0.000 006%-0.000 08%.
The method shows the advantages of high sensitivity, good accuracy, linearity and can be used for the detection of genetic impurities in HPDSP.
To establish a suitable method to determine the structure and source of impurities of colistimethate sodium (CMS) for drug quality control studies.
Frist-dimensional system: using Acquity UPLC® Peptide CSH C18(150 mm×2.1 mm, 1.7 μm) column, the mobile phase A was phosphate buffer (7.8 g·L-1 sodium dihydrogen phosphate, adjusted to pH 6.4 with 1 mol·L-1 sodium hydroxide)- acetonitrile (19∶1), the mobile phase B was phosphate buffer-acetonitrile (1∶1). Gradient elution was performed at a flow rate of 0.3 mL·min-1. The column temperature was 30 ℃. Second-dimensional system: the Acquity BEH C18 column (50 mm×2.1 mm, 1.7 μm) column was used with ammonium formate(A)-acetonitrile mixture as mobile phase with gradient elution. The flow rate was 0.2 mL·min-1. The column temperature was 40 ℃. The detection wave length was 210 nm. The ESI source was used in negative ion mode.
The 2D-LC-Q TOF MS method was used to infer the structure of the 55 impurities in CMS, and the main sources were polymyxin E1-I, polymyxin E1-7MOA, polymyxin E3 and polymyxin E6.
The structure and source of impurities in CMS are determined by 2D-LC-Q TOF MS, and the changes in the content of impurities such as manufacturers and production processes are evaluated, which is conducive to improving the production process and controlling drug quality at the source.
To establish an HPLC method for the determination of the related substances in telmisartan.
Waters Symmetry Shield RP8 (150 mm×4.6 mm, 3.5 μm) column was adopted. The mobile phase A was 0.1% phosphoric acid solution (pH was adjusted to 3.0 with triethylamine), and the mobile phase B was acetonitrile. The gradient elution was performed. The flow rate, column temperature and wavelength were 0.8 mL·min-1, 25 ℃ and 230 nm, respectively.
The resolutions between the peaks of telmisartan and nine known impurities were greater than 1.5. The limits of quantitation of all impurities were less than 40 ng·mL-1, and the limits of detection of all impurities were less than 10 ng·mL-1. The standard curves of telmisartan and its impurities were linear within the range 30-600 ng·mL-1, and the correlation coefficients were all greater than 0.999 5. The average recovery rates of impurities Ⅰ-Ⅸ were 93.8%, 99.8%, 97.5%, 99.2%, 99.8%, 98.3%, 98.4%, 99.2% and 99.7%, respectively, and the RSDs of 9 results were all less than 2.0%. Changing the flow rate, column temperature, wavelength, mobile phase ratio and pH did not affect the detection results of the related substances. The results of maximum single impurity were 0.02% in three batches of telmisartan, and the results of total impurities were less than 0.10%.
The method is highly specific, sensitive, precise and accurate, and can be used for the determination of related substances of telmisartan.
To study and analyze rapid evaporative ionization mass spectrometry (REIMS) fingerprints of samples of Fritillariae Thunbergii Bulbus and Fritillariae Hupehensis Bulbus in different forms for authenticity discrimination with machine learning.
Aerosol formations from the samples by high temperature of dry burning method were ionized and determined by REIMS with m/z 50-1 200 as scanning range in sensitive mode and positive ion mode. The scanning time was 0.2 s and data was recorded as continuous mode. Then the basic situation of REIMS data distribution was studied and analyzed through the methods of cluster analysis, correlation analysis, similarity analysis and principal component analysis. And then logistic regression model with ridge regression (l2) as penalty parameter and quasi-Newton method (lbfgs) as optimization algorithm was established.
The REIMS fingerprints of the samples showed the characteristics of variety differences. Both cross validation and test set validation had an accuracy of 1.0, and the logistic regression model could accurately predict and distinguish the varieties of the samples.
The application prospect of REIMS technique combined with machine learning in the field of traditional Chinese medicine is very broad.
To investigate the accumulation pattern of metabolites in Glycyrrhiza uralensis by qualitative and quantitative analyses of metabolic constituents in Glycyrrhiza uralensis with different cultivation years, and to search for its differential metabolites.
The separation was performed on an Agilent SB-C18 (100 mm×2.1 mm, 1.8 μm) column with 0.1% formic acid aqueous solution as the mobile phase A and 0.1% formic acid acetonitrile solution as the mobile phase B. The gradient elution was carried out at a flow rate of 0.35 mL·min-1, and the column temperature was 40 ℃ with an injection volume of 4 μL. The mass spectrometry was performed with positive and negative ions scanning in multiple reaction monitoring mode. The mass spectrometry was performed in multi-response monitoring mode with positive and negative ion scanning. The qualitative and quantitative analyses of the metabolites in Glycyrrhiza uralensis were carried out on the basis of the self-constructed secondary mass spectrometry database, and the multivariate statistical analyses of the metabolites of Glycyrrhiza uralensis with different cultivation were combined with principal component analysis(PCA), orthogonal partial least squares discriminant analysis(OPLS-DA), and cluster heat map analyses.
(1) A total of 1 038 metabolites were detected from the samples of Glycyrrhiza uralensis with different cultivation years, among which 201 differential metabolites existed between annual and biennial Glycyrrhiza uralensis, 125 up-regulated and 76 down-regulated; 223 differential metabolites existed between biennial and three years old Glycyrrhiza uralensis, 64 up-regulated and 159 down-regulated; 185 differential metabolites existed between annual and three years old Glycyrrhiza uralensis, 59 up-regulated and 126 down-regulated. Four metabolites specific to annual Glycyrrhiza uralensis, six to biennial and one to three-year old were found. (2) K-mean cluster analysis was performed on the differential metabolites, and the differential metabolites were classified according to the different accumulation trends, and it was found that most of the metabolites such as flavonoids, phenolic acids, terpenes, lignans, and coumarins peaked in biennial Glycyrrhiza uralensis, and most of the metabolites such as alkaloids, amino acids and their derivatives peaked in annual Glycyrrhiza uralensis, and a part of the flavonoids, phenolic acids and other metabolites reached peaks in three years old Glycyrrhiza uralensis, suggesting that the metabolism of Glycyrrhiza uralensis in the body reached the peaks. peak value, suggesting that there was a certain pattern of metabolite content changes in Glycyrrhiza uralensis. (3) 160 differential metabolites annotated in Kyoto Encyclopedia of Genes and Genomes (KEGG) datebase and flavonoids, amino acids and their derivatives, and organic acids were the differential metabolites that accounted for a relatively large number of them. A total of 79 differential metabolic pathways were enriched among different comparison groups, among which 6 differential metabolic pathways were highly significantly enriched (P<0.01) and 23 significantly enriched (P<0.05), and the distributions of compounds involved in the above pathways were basically the same as before enrichment in comparison of different cultivation year.
The present study elucidate the differences between the metabolic components of Glycyrrhiza uralensis with different cultivation years, and further analyse the metabolic pathways that might cause the differences through the differential metabolites, which can provide a certain reference basis for the determination of the harvesting year of Glycyrrhiza uralensis and the study of the quality formation mechanism.
To explore the prepararation methods and rules of hair quality control samples which contained ketamine, norketamine or fluoroketamine, and the effects of different preparation and storage conditions on the performance of hair quality control samples.
Different preparation conditions were compared, such as different types of soaking solutions, solutions with different target contents, different amount of blank hair etc. The performances of hair quality control samples which were prepared in different conditions were systematically analyzed, and eighteen kinds of hair quality control samples with different contents of targets and different forms were prepared according to the rules, ACN-DMSO (1∶1, v/v, added 0.02 mol·L-1 hydrochloric acid) was used to soak blank hair in different time periods to prepare hair quality control samples with a wide coverage. HPLC-MS/MS instruments and BEH C18(100 mm×2.1 mm, 1.7 μm) column were used to test the content of targets in hair. Column temperature was 40 ℃, the mobile phases were aqueous solution with 0.1%(v/v) formic acid (A)-acetonitrile aqueous solution with 0.1%(v/v) formic acid (B), gradient elution (0-9 min, 5% B→100% B; 9-11 min, 100% B; 11-11.1 min, 100% B→5% B; 11.1-13 min, 5% B, a flow rats of 0.4 mL·min-1, inject volume of 1 μL. The homogeneity, short term and long term stability in different storage conditions (temperature, humidity, light conditions, etc.) were also investigated.
The influences of different preparation conditions on the hair quality control samples were determined, soaking solutions had strong influences on the hair quality control samples, however the amount of blank hair had nearly no effects. All the samples prepared were uniform, F of each sample was lower than F0.05(table) (3.02) according to the F-test method, and all the samples were stable, during storage at room temperature, refrigerated or frozen conditions for 6 months, the contents of the target substances in each sample were monitored, all of RSDs were <12%, and the t values of each sample were < t(0.05)(table) (2.131 8) according to the T-test method.
This study provides preparation rules of hair quality control samples and also provides detailed reference data for subsequent preparation and storage of related hair quality control samples.
To develop the first batch of traditional Chinese medicine chemical reference substance 2-acetate regaloside A used in standard of Baihe (Juandan) Peifang Keli.
The structure was elucidated by nuclear magnetic resonance spectrometry, mass spectrometry, ultraviolet spectroscopy and infrared spectroscopy. Purity analysis, determination of related substance and investigation of other physical and chemical parameters were carried out by using analytical different techniques such as high performance liquid chromatography, gas chromatography, coulometry and ignition residue method. On the above basis, the mass balance was used for value determination, and the 1H quantitative nuclear magnetic resonance method was applied for further verification.
The structure of the traditional Chinese medicine chemical reference substance was determined as 2-acetate regaloside A, and it was identified as a new compound by SciFinder search. The calibration value by mass balance method was 99.31%, and result of 1H quantitative nuclear magnetic resonance method was 100.06% (n=3, RSD=0.47%).
The accurate development and calibration of the first batch of 2-acetate regaloside A fully ensures the implementation of the standard for Baihe (Juandan) Peifang Keli.
To establish an immunochromatographic method suitable for the rapid detection of residues of triazine herbicide prometryn in Chinese medicine, based on self-made prometryn antigen and monoclonal antibody.
An antibody conjugate amount of 7 μg and dilution configuration of 0.1 mol·L-1 PBS with 1% OVA, 0.1% Tween-80 were determined, and dry test strips with a T-line scribing concentration of 0.05 mg·mL-1 and a C-line scribing concentration of 0.5 mg·mL-1 were used. The suitable method was selected to improve the sensitivity of colloidal gold immunochromatography test strip, reduce the matrix effect of traditional Chinese medicine in different parts, and detect a large number of traditional Chinese medicine.
The detection sensitivity of the test strip could reach 1 ng·mL-1, and the detection limit of the actual sample could reach 0.1 mg·kg-1. The established method was suitable for the detection of prometryn residues in 40 kinds of Chinese medicinal materials such as Citri Reticulatae Pericarpium, Taraxaci Herba, Notoginseng Radix et Rhizoma andLonicerae Japonicae Flos.
This method has the advantages of rapid and accurately detection, simple pretreatment, simple operation and strong generalization, and can be used as an effective method for rapid screening of prometryn residues in the field, so as to ensure the quality and safety of traditional Chinese medicine. At the same time, this study has a certain reference significance for the development of rapid detection of agricultural residues in many kinds of traditional Chinese medicine.