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This study describes the enantioseparation of three chiral amines as naphthaldimine derivatives, using normal phase HPLC with amylose and cellulose tris(3,5-dimethylphenylcarbamate) chiral stationary phases (CSPs). Three chiral amines were derivatized using three structurally similar naphthaldehyde derivatizing agents, and the enantioselectivity of the CSPs toward the derivatives was examined. The degree of enantioseparation and resolution was affected by the amylose or cellulose-derived CSPs and aromatic moieties as well as a kind of chiral amine. Especially, efficient enantiomer separation was observed for 2-hydroxynapthaldimine derivatives on cellulose-derived CSPs. Molecular docking studies of three naphthaldimine derivatives of leucinol on cellulose tris(3,5-dimethylphenylcarbamate) were performed to estimate the binding energies and conformations of the CSP-analyte complexes. The obtained binding energies were in good agreement with the experimentally determined enantioseparation and elution order.

Recent studies strongly suggest that atorvastatin combination therapy with tangeretin could be beneficial in the treatment of hyperlipidemia. This study aimed to investigate the pharmacokinetic interactions among atorvastatin, its active metabolite 2-hydroxy atorvastatin, and tangeretin after oral administration of atorvastatin with tangeretin in rats. A rapid, selective, and sensitive assay was developed and validated based on ultra-high performance supercritical fluid chromatography-tandem mass spectrometry for the simultaneous measurement of atorvastatin, 2-hydroxy atorvastatin, and tangeretin concentrations in rat plasma. Chromatographic separation of the analytes was conducted on an ACQUITY Torus 1-AA column in gradient elution mode. The mass transition ion pairs were m/z 559.0→440.0 for atorvastatin, m/z 575.2→440.0 for 2-hydroxy atorvastatin, m/z 373.0→358.1 for tangeretin, and m/z 254.8→136.7 for daidzein (internal standard). Calibration curves showed good linear correlations at the following concentration range: 1-400 (r = 0.9952), 1-400 (r = 0.9980), and 3-1200 (r = 0.9945) for atorvastatin, 2-hydroxy atorvastatin, and tangeretin, respectively. The method was fully validated and satisfied the acceptance criteria recommended by the United States Food and Drug Administration. Finally, it was successfully applied in a pharmacokinetic study in rats to evaluate the pharmacokinetic behavior of atorvastatin, 2-hydroxy atorvastatin, and tangeretin.

In this study, magnetic pomelo peel-derived biochar composite was fabricated and applied as a low-cost adsorbent for the simultaneous extraction of morphine-like opioids named morphine, codeine, and 6-monoacetylmorphine from wastewaters, prior to their determination via liquid chromatography-mass spectrometry. A total of four biochar products were synthesized under different pyrolytic temperatures of 400, 500, 600, and 700°C, respectively, and the 400°C biochar was found to have the greatest extraction ability, with enrichment factors of 34, 58, and 61 for the three drugs. The primary adsorption mechanism includes π-π interaction and H-bonding. Parameters affecting the extraction of opioids were optimized. Under optimum conditions (such as pH = 7; adsorbent amount = 15 mg; sample volume = 20 ml; eluent solvent, 200 µl of methanol), the method was proved to be linear in the range of 0.05-10.0 µg/L, with coefficients of determination greater than 0.99, and the limits of detection were 0.006-0.010 µg/L. In-batch and inter-batch precisions were 1.8%-6.5% and 4.8%-10.6%, respectively. The method was successfully applied to the determination of the target opioids in the samples of influent and effluent wastewater. The developed method by using magnetic pomelo peel-derived biochar could potentially be applied for the effective estimation of illicit drug consumption.

Areca nut is a popular and addictive food as well as a traditional herbal medicine in many countries. Areca nut contains alkaloids including arecoline, guvacine, and arecaidine, which are the major bioactive compounds in areca products. Areca alkaloids can be carcinogenic, and thus sensitive and specific analytical methods are urgently desired for the identification and quantification of these compounds. High-performance liquid chromatography-based methods are often preferred, but areca alkaloids do not have chromophores, and detection using a traditional UV detector can be difficult. The complexity of areca sample extracts can also lead to the co-elution of peaks leading to poor quantitative performance. We report here high-performance liquid chromatography coupled with an ion mobility spectrometer for sensitive determination of areca alkaloids in various products including areca nut, areca nut products, and herbal oral liquid. An X-Bridge reversed-phase C

Gerberae Piloselloidis Herba, a traditional Chinese medicine, is often employed to treat such lung-related diseases as coughs, asthma, and pulmonary carbuncles in southwest China. Our previous study demonstrated that its active fraction, prepared from Gerberae Piloselloidis Herba, exerts an obvious beneficial effect on asthma. However, the pharmacokinetics of its major constituents remain unclear. Therefore, an ultra-performance mass spectrometry-electrospray ionization-tandem mass spectrometry method was successfully established to simultaneously perform the pharmacokinetics of the main 11 components of the active fraction between normal and ovalbumin-induced asthmatic mice. Compared to the normal group, in asthmatic mice the peak concentration of arbutin, marmesin, caffeoylquinic acids, and flavonoid glycosides clearly increased, while for luteolin it significantly declined; the area under the curve for arbutin and luteolin showed an increase, but the values of marmesin, caffeoylquinic acids, and flavonoid glycosides revealed a decline; the peak time for arbutin, caffeoylquinic acids and flavonoid glycosides decreased, while for marmesin and luteolin it significantly augmented; apart from marmesin, the half-life for all compounds shortened significantly. It is indicated that the pathology of asthma could lead to an alteration in the pharmacokinetic profiles of the 11 components in plasma, providing a reference for further exploration of the pharmacodynamic basis of the anti-bronchial effect of Gerberae Piloselloidis Herba.

Chloride is the most common counterion used to improve aqueous solubility and enhance stability of small molecule active pharmaceutical ingredients. While several analytical techniques, such as titration, HPLC with charged aerosol detection, and ion chromatography, are currently utilized to assay the level of chloride, they have notable limitations, and these instruments may not be readily available. Here, we present a generally applicable

In the present study, an efficient strategy for the large-scale preparation of two minor polar polyphenols from Phyllanthus emblica L. has been established by macroporous resin column chromatography and high-temperature preparative high-speed counter-current chromatography. Macroporous resin column chromatography was used for the enrichment of the target polyphenols. The target polyphenols could be well enriched in the 10% ethanol fraction and the peak area proportion increased from 2.2% in the crude extract to 85.3% in the 10% ethanol fraction. Then, the 10% ethanol fraction was introduced to preparative high-speed counter-current chromatography for separation using an n-butanol-ethyl acetate-water (17:3:20, v/v/v) solvent system. In order to improve the retention of the stationary phase, a high-temperature preparative high-speed counter-current chromatography had been developed by using a 316 L stainless steel pipe as a column. A 50°C of column temperature was used and the retention rate of the stationary phase could reach 75%. Finally, 871 mg of compound Ⅰ and 534 mg of compound Ⅱ with purities higher than 98% were obtained from 4 g of the sample. The chemical structures were identified as corilagin and 1, 6-di-O-galloyl-β-D-glucoside by

Moscatilin, a bioactive ingredient isolated from Dendrobium moscatum, has been demonstrated to have excellent anti-cancer activity. The goals of the present study were to investigate the metabolic profiles of moscatilin and to identify and characterize its metabolites. In vitro studies were performed by incubating moscatilin (10 μM) with rat, dog, monkey, and human liver microsomes (0.5 mg protein/ml) to generate the metabolites. An analytical method of liquid chromatography combined with hybrid quadrupole orbitrap high-resolution mass spectrometry in full mass/data-dependent tandem mass spectrometry scan was utilized to separate and identify the metabolites in accordance with their accurate masses, formulas, and tandem mass spectrometry fragment ions determination. A total of six phase I metabolites were detected and structurally characterized. The phase I metabolic pathways of moscatilin were hydroxylation, demethylation, and dehydrogenation. In glutathione-supplemented liver microsomes, nine glutathione conjugates were detected and identified. Our results demonstrated that moscatilin was susceptible to bioactivation with the result of ortho quinone and quinone-methide intermediates. The present study provided an overview of the in vitro metabolic profiles of moscatilin, which will aid in the understanding of the efficacy and safety of this active compound.

Solid phase extraction combined with ultra-performance liquid chromatography-tandem mass spectrometry was developed for the simultaneous determination of 31 endocrine-disrupting chemicals in fish plasma. The strong anion exchange/primary-secondary amine cartridge and the mixed cation exchange cartridge were used in tandem instead of using a single mixed cation exchange cartridge for sample purification. Suitable eluents were selected for each of the two cartridges: 4.5% ammonia/acetonitrile solution for cartridges in tandem and acetone:n-hexane (V:V = 3:7) for the strong anion exchange/primary-secondary amine cartridge alone. With this optimized Solid phase extraction method, the recoveries of 31 endocrine disrupting chemicals were between 43.0% and 131.3%, the method detection limits were 0.45 to 1.35 ng/ml, and the limits of quantitation were 1.50-4.50 ng/ml. The innovative pretreatment method that connects two cartridges in tandem is well positioned to mitigate the matrix effects of fish plasma, thereby improving the accuracy of multiclass endocrine-disrupting chemicals determination. The significance of this method is to facilitate the application of the fish plasma model for the environmental risk assessment of endocrine-disrupting chemicals.

Successful isolation of 15 compounds from Polygonti rhizome was obtained by an efficient technique combined with macroporous resin column chromatography pretreatment and three different modes of high-speed counter-current chromatography for the first time. For the pretreatment, AB-8 resin was applied to remove the polysaccharides and enrich four different parts (samples I, II, III, and IV) by polarities. For the separation, sample I was separated by pH-zone-refining counter-current chromatography and seven cycle recycling mode high-speed counter-current chromatography, yielding four alkaloids (1--4); samples II-IV were further separated by the conventional high-speed counter-current chromatography, yielding seven flavonoids (5-10, 12), one steroid saponin (11), and three terpenoids (13-15). Finally, the isolates were assayed for their anti-inflammatory activities against nitric oxide production with compounds 5, 9-10, 13 showing significant anti-inflammatory activities, IC

The total lignans from Fructus arctii (TLFA) is a mixture of a series of lignans isolated from dried ripe fruit of Arctium lappa L. We previously reported on the pharmacological activity of TLFA that is related to diabetes. An accurate and practical TLFA quantitative analysis method for utilising it needs to be established.This study aimed to develop an effective quantitative analysis method for assessing the TLFA quality.A total of 11 marker components were confirmed by analysing the high-performance liquid chromatography fingerprints of 24 batches of TLFA samples. The samples were prepared from TLFA and structurally identified as lappaol H, lappaol C, arctiin, arctignan D, arctignan E, matairesinol, arctignan G, isolappaol A, lappaol A, arctigenin, and lappaol F. In the quantitative analysis of multi-components by the single-marker (QAMS) method and with arctiin as an internal reference substance, the content of these lignans in TLFA was simultaneously determined according to their relative correction factors with arctiin.There was no significant difference between results measured by the QAMS and traditional external standard methods. Hierarchical cluster and principal component analyses were performed to evaluate 24 TLFA batches based on the contents of 10 marker components. The results revealed that QAMS method combined with chemometric analyses could accurately measure and clearly distinguish the different quality samples of TLFA.The QAMS method is a reliable and promising quality control method for TLFA. It can provide a reference for promoting quality control of complex multi-component systems, especially for traditional Chinese medicine.

Abemaciclib is an effective selective cyclin-dependent kinases 4 and 6 inhibitors for cancer therapy. The abemaciclib-related substances influence its efficacy and safety, and are important in process preparation studies and quality control. Thus, a reversed-phase high-performance liquid chromatography method was developed and validated for the detection of related substances in its bulk drug. The separation of abemaciclib and related substances was performed on a Phenomenon Gemini C18 column (4.6 × 250 mm, 5 μm) with a flow rate of 1.0 ml/min. The ultraviolet detection wavelength was 280 nm. Mobile phase A was composed of a mixed solution of aqueous solution and acetonitrile (9:1, v/v). The aqueous solution (pH 2.5) contained 0.025-mM potassium dihydrogen phosphate solution and 0.4% triethylamine. Mobile phase B was composed of acetonitrile. This novel method exhibits good system suitability, specificity, precision, stability, linearity (0.1-20 μg/ml), repeatability, and durability. Among abemaciclib and related substances, the lowest limit of detection and quantitation were 0.02 and 0.06 μg/ml, respectively, for abemaciclib. The recovery rates for related substances were above 95%. In addition, a novel degradation product was found during the process. In summary, a reliable reversed-phase high-performance liquid chromatography method was developed for abemaciclib-related substance detection in bulk drugs.

Ochratoxin A (OTA) is a mycotoxin produced by several species of Aspergillus and Penicillium and commonly detected in a wide range of foodstuffs. The purpose of this work was to monitor the presence of OTA in cheeses and pork meat products. A simple and accurate "dilute and shoot" method with no need of immunoaffinity column and isotopic labeled internal standard, by liquid chromatography-tandem mass spectrometry, was validated in accordance with the criteria set out in Commission Regulation (EC) No. 401/2006. The method showed good linearity in solvent and in matrix (R

Metformin is one of the most commonly used drugs in the world for the treatment of type 2 diabetes, while ferulic acid is a molecule that stands out for its antioxidant potential. Recent studies demonstrate hypoglycemic synergy between these molecules. The objective of this study is to develop and validate an analytical methodology by high-performance liquid chromatography for the simultaneous quantification of these drugs in pharmaceutical formulations. The method used an octadecylsilane column and a mobile phase composed of 6 mM sodium lauryl sulfate in 15 mM phosphate buffer:ACN (65:35). Ferulic acid and metformin were monitored at 232 nm, with a mobile phase flow rate of 1 ml/min and oven temperature at 40°C. The method was linear in the range of 5-25 μg/ml for both molecules. In the presence of degradation products, satisfactory selectivity was achieved. Accuracy values were close to 100% and standard deviations in precision were less than 2%. In the robustness evaluation, the proposed variations did not interfere with the quantification. Therefore, it is concluded that the present method can be safely applied to the quality control of ferulic acid and metformin raw materials, as well as when they are combined in pharmaceutical formulations.

3-Nitropropionic acid (3-NPA) is a toxic compound that can accumulate in esterified form in the Fabaceae family. In the Lotae tribe, many species have been identified as 3-NPA producers (e.g., Securigera varia), while some of the genetically close Lotae plants were formerly reported as 3-NPA-free (e.g., Lotus corniculatus and Anthyllis vulneraria). These plants are used as forage and have a tradition in ethnomedicine, also, the extracts of A. vulneraria are used in cosmetics.Our aim was to investigate the 3-NPA content of these selected Fabaceae species and to develop a validated quantitative method to evaluate 3-NPA concentrations in extracts of different herbal parts and cosmetic products.A UHPLC-ESI-Orbitrap-MS/MS method was applied for detection and identification of 3-NPA derivatives in the form of glucose esters. For the quantitative analysis, an optimized sample processing method was developed. The free 3-NPA content was determined using HPLC-ESI-MS/MS.3-NPA esters could be detected in all three species, but their quantity showed a high variation. S. varia contained 0.5-1.0 g/100 g of 3-NPA, while in L. corniculatus samples only trace quantities were detectable, below the LOQ (25 ng/ml). Most of the A. vulneraria samples showed similarly low concentrations, but one sample had 3-NPA levels comparable to S. varia. 3-NPA could not be detected in the tested cosmetics containing A. vulneraria extracts.Using highly sensitive analytical methods, new 3-NPA-containing species were identified. The developed validated quantitative method is suitable for the determination of 3-NPA concentrations in herbal samples.

Chrysanthemum is one of the most important and popular ornamentals over the world. Chrysanthemum drink is a type of traditional healthy drink like Chinese tea. Owing to the differences in the chemical compositions, different chrysanthemum varieties have different medicinal effects on human health. Thus, the identification of different chrysanthemum varieties is very important and necessary. This study aims to distinguish seven chrysanthemum varieties that are widely used in China. First, total lipids were obtained from chrysanthemums. After that, lipid profiles were characterized using ultra-high-performance liquid chromatography hyphenated with a Q Exactive™ high resolution-accurate-mass mass spectrometer.A total of 163 lipid molecular species from 17 types of lipid classes in seven varieties of chrysanthemums were determined. Principal component analysis indicated that three lipid molecules, lysophosphatidylethanolamine(18:2) (LPE(18:2)), LPE(16:0), and phosphatidic acid(18:2/18:3) (variable importance in projection3, P 0.001), can be used as potential biomarkers to distinguish seven chrysanthemum varieties. Hierarchical cluster analysis showed that the lipid molecular profiles of 'Gongju' were most similar to 'Jinzijianju', followed by 'Huaibaiju', 'Boju', 'Hangbaiju', 'Chuju', and 'Fubaiju'.This comprehensive analysis provided a new method to identify chrysanthemum varieties through the perspective of lipidomics combined with chemometrics. © 2022 Society of Chemical Industry.

As the most abundant and bioactive constituent in vine tea (Ampelopsis grossedentata), dihydromyricetin possesses numerous biological activities. A rapid profiling and identification method for dihydromyricetin metabolites in rats after the oral administration has been established using ultra-high-performance liquid chromatography-Q-Exactive Orbitrap mass spectrometry coupled with multiple data-mining methods. Herein, an efficient analytical strategy characterized by a parallel reaction monitoring mode combining diagnostic fragment ions filtering techniques was developed for the comprehensive identification of dihydromyricetin metabolites in rat plasma, urine, and feces. And then, the biotransformation pathways of dihydromyricetin were further revealed. As a result, a total of 49 metabolites were finally identified by comparing diagnostic fragment ions, chromatographic retention times, neutral loss fragment ions, and accurate mass measurement with those of the dihydromyricetin reference standard. These metabolites were presumed to be dominantly generated through hydroxylation, dehydroxylation, methylation, reduction, sulfation, decarbonylation, glucuronidation, glucosylation, and their composite reactions. In a word, our present results not only supplied a solid foundation to better understand the action mechanism of dihydromyricetin, but also provided some models for the metabolism study of the other compounds in traditional Chinese medicines or natural plants.

The current research explains the stress degradation behavior of Apixaban, which is an anticoagulant or blood thinner. The degradation was conducted using hydrolytic, oxidative, thermal, and photolytic conditions. Apixaban is relatively stable in oxidative, thermal, and photolytic conditions; however, considerable degradation was observed in acid and base hydrolysis. Degradation products were identified using ultra-high performance liquid chromatography-mass spectrometry, isolated using semi-preparative high-performance liquid chromatography, and structural characterization by high-resolution mass spectrometry and nuclear magnetic resonance spectroscopy. A total of five degradation products were identified and isolated in acid and base degradation. Degradation products 1, 2, and 3 were observed in acid conditions, whereas in base conditions, along with those three, two more degradation products 4 and 5 were identified. The representative thing was that among the five degradation products, two sets of positional isomers 1, 4, and 2, 5 were observed; out of which 2 and 5 are novel. The remaining degradation products 1, 3, and 4 are already reported tentatively using a single analytical technique of mass analysis without any evidence from nuclear magnetic resonance spectroscopy. Hence, the present study focused on using high-resolution mass, and nuclear magnetic resonance spectroscopy data for concrete confirmation of structures for degradation products.

North Patrininae herba, a perennial herbaceous plant, has long been used in traditional Chinese medicine to treat appendicitis, enteritis, and dysentery. Sonchus arvensis L., Sonchus oleraceus L., and Ixeris chinensis (Thunb.) Nakai are used as substitutes for North Patrininae in different regions, but the consistency of chemical composition and efficacy of these three species is still unknown. In this study, a detailed chemical analysis was carried out of the extract obtained from Sonchus arvensis L., Ixeris chinensis (Thunb.) Nakai and Sonchus oleraceus L. and a chemical component not previously reported in Ixeris chinensis (Thunb.) Nakai was found-Luteolin-7-O-(6''-malonylglucoside). The mechanism of action of the extract against inflammation and type II diabetes was investigated using network pharmacology and analysis of blood-absorbed components following oral dosing of rats. Finally, a highly accurate and reliable method was established for quality control purposes. The results showed that Sonchus arvensis L. and Sonchus oleraceus L. may be considered potential resources of a medicinal compound, whereas Ixeris chinensis (Thunb.) Nakai requires further evaluation.

Coreopsis tinctoria Nutt. (family Asteraceae) is a popular medicine-food plant, which improves chronic diseases such as hyperlipemia, hypertension, and diabetes. Flavanomarein is the main active component of Coreopsis tinctoria Nutt, in which the blood concentration of volunteers is low and bioavailability is poor. Thus, the understanding of flavanomarein metabolites and metabolic pathways is significant to clarify its effectiveness. This study systematically studied the metabolites of flavanomarein by oral and injection. The biological samples (feces, urine, and plasma) were analyzed by ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry in negative ion mode. The metabolic law of flavanomarein in the liver was further verified by a liver microsomal incubation experiment in vitro. A total of 12 metabolites were identified by oral administration while 15 metabolites were detected by injection. It was shown that metabolic pathways include acetylation, hydroxylation, glucuronidation, methylation, dehydrogenation, and so forth. The liver extraction rate of flavanomarein was 0.08, which means the metabolic stability of flavanomarein is well in rats' liver microsomes. It is a systematic study on the metabolism of flavanomarein and provides a metabolic rationale for further in-depth in vivo biotransformation.

Zhizi Baipi decoction is a classic traditional Chinese medicine formula for the treatment of jaundice and various liver diseases. The chemical components of Zhizi baipi decoction were not clear resulting of the paucity of relevant studies, which hindered the elucidation of the pharmacological mechanism, and the comprehensive development and utilization of Zhizi baipi decoction in clinical. In this study, ultra-performance liquid chromatography-quadrupole-time of flight mass spectrometry combined with the UNIFI natural product information analysis platform was used to rapidly analyze and identify the chemical components in Zhizi baipi decoction. A total of 122 chemical components, including 53 flavonoids, 16 alkaloids, 25 terpenoids, five phenylpropanoids, 14 organic acids, and seven others, were identified from Zhizi baipi decoction. These compounds may be the active components of Zhizi baipi decoction. The method established in this study can systematically, rapidly, and accurately resolve the chemical components in Zhizi baipi decoction, which lays the foundation for further establishment of the pharmacodynamic substance basis and quality control of Zhizi baipi decoction.

Assignment of inorganic mercury and methyl mercury mass fractions at an ultratrace level in soil certified reference material EnvCRM 03 with a complex matrix composition was undertaken. Inorganic mercury and methyl mercury contents by species-specific isotope dilution inductively coupled plasma mass spectrometry with on-line high-performance liquid chromatography or with classical off-line chromatography were established. Different extraction protocols: sequential extraction ((1) H

Favipiravir and Meropenem have been concurrently used as directly acting antiviral and antibiotic agents for the treatment of coronavirus disease in human plasma. Accurate and specific reversed phase ultra-performance liquid chromatographic and high-performance thin-layer chromatographic methods were developed and validated for the first time analysis of this combination in spiked human plasma using Cefepime as an internal standard. In the developed ultra-high-performance liquid chromatography method, separation was performed on a BEH C18 column with a mixture of ACN and 0.05 M potassium dihydrogen orthophosphate (pH = 3) in a ratio of 10:90 (v/v) as an eluate. Scanning of the separated peaks was at 298 nm. The developed method showed high sensitivity, and the drugs showed linearity in the range of 5-70 μg/ml for Favipiravir and 2-50 μg/ml for Meropenem. The proposed high-performance thin-layer chromatographic method included the separation using a mixture of ethyl acetate:methanol:deionized water:formic acid (5:4:1.5:0.3, by volume), then spots detection at 300 nm. Methods were investigated for greenness using the eco-scale and national environmental method index tools and were validated according to food and drug administration guidelines. Methods can be applied for bio-analysis and therapeutic drug monitoring studies.

Pavel Jandera was a world-leading analytical chemist who devoted his entire professional life to research in the field of high-performance liquid chromatography. During his scientific career, he worked at the Department of Analytical Chemistry at the University of Pardubice, Czech Republic. His greatest contribution to the field of liquid chromatography was the introduction of a comprehensive theory of liquid chromatography with programmed elution conditions. He was also involved in the research of gradient elution techniques in preparative chromatography, modeling of retention and selectivity in various phase systems, preparation of organic monolithic microcolumns, and, last but not least, in the development of theory and practical applications of two-dimensional liquid chromatography, mainly in the comprehensive form. In this review article, we have tried to capture the highlights of his scientific career and provide the readers with a detailed overview of Pavel Jandera's contribution to the evolution of separation sciences.

Cell membrane ligand-affinity assay is a useful tool for screening the active compounds from natural products. However, in traditional cell membrane ligand-affinity assays, natural products need to be refluxed, before being analyzed. This process consumes considerable time and energy and cannot be used for screening natural products that contain thermally unstable compounds. Therefore, an efficient analytical method is required. In this study, chitosan-based matrix solid-phase dispersion extraction was combined with cell membrane magnetic bead ligand-affinity assay to form a novel method for identifying the active compounds in Fructus Cnidii such as osthole and imperatorin. When compared with traditional cell membrane ligand-affinity assays, this assay requires less energy, extraction time (7 min), solvent volume (1.2 mL), and fewer natural products (40 mg). This indicates that the chitosan-based matrix solid-phase dispersion extraction assisted cell membrane magnetic beads ligand-affinity assay is an alternative analytical method for studying natural products.

A simple stability-indicating reversed-phase high-performance liquid chromatography method has been developed for determination of elobixibat in presence of its potential impurities and degradation products. The chromatographic separation was carried on a Thermo scientific Base Deactivated Silica BDS Hypersil-C18 (150 × 4.6 mm; 5 μm) column using a mobile phase of acetonitrile and phosphate buffer (25 mM, pH 2.5) in a ratio of (70:30, v/v). The experimental conditions were accurately investigated, and the method was validated according to ICH guidelines Q2 (R1). The drug was subjected to various stress conditions including acidic, basic, oxidative, and photolytic conditions. The method successfully separates the drug from the three reported impurities and different degradants. The method was also successfully applied for the determination of elobixibat in laboratory prepared tablets (5.0 mg). Analysis shows no interference from excipients and degradation products. The method was also applied for performing in vitro dissolution testing of elobixibat laboratory prepared tablets. Since elobixibat is recently introduced into the market, there are no previous stability studies and no reported analytical methods for its determination. Thus, this study presents a validated and selective method that can be effectively employed in routine quality control studies.

The composition of the traditional Chinese medicine compound preparation is complex, while the content of each active ingredient is extremely low, which brings difficulties to the plasma concentration detection. In this study, the magnetic covalent-organic frameworks were synthesized by a simple one-step Schiff base reaction and applied for the specific extraction of trace angoroside C in rat plasma prior to ultra-high-performance liquid chromatography-tandem mass spectrometry detection. The synthesized magnetic covalent-organic frameworks have high magnetic responsiveness (35.67 emu·g

Harvest time plays an important role on the quality of medicinal plants. The leaves of Crataegus pinnatifida Bge. var major N.E.Br (hawthorn leaves) could be harvested in summer and autumn according to the Pharmacopoeia of the People's Republic of China (Pharmacopoeia). However, little is known about the difference of the chemical constituents in hawthorn leaves with the harvest seasonal variations.The chemical constituents of hawthorn leaves in different months were comprehensively analysed to determine the best harvest time.Initially, the chemical information of the hawthorn leaves were obtained by ultra-high-performance liquid chromatography and quadrupole time-of-flight mass spectrometry (UHPLC-Q-TOF-MS). Subsequently, principal component analysis (PCA) was applied to compare the chemical compositions of hawthorn leaves harvested in different months. Then, an absolute quantitation method was established using high-performance liquid chromatography-charged aerosol detector (HPLC-CAD) to determine the contents of five compounds and clarify the changes of these components with the harvest seasonal variations. Meanwhile, a semi-quantitative method by integrating HPLC-CAD with inverse gradient compensation was also established and verified.Fifty-eight compounds were identified through UHPLC-Q-TOF-MS. PCA revealed that the harvest season of hawthorn leaves had a significant effect on the chemical compositions. The contents of five components were relatively high in autumn. Other four main components without reference standards were further analysed through the semi-quantitative method, which also showed a high content in autumn.This work emphasised the effect of harvest time on the chemical constituents of hawthorn leaves and autumn is recommended to ensure the quality.

Shengjiang Xiexin decoction, a traditional Chinese medical formula, has been utilized to alleviate the delayed-onset diarrhea induced by irino tecan. However, the chemical constituents of this formula and the activities of its constituents remain unclear. In this study, ultrahigh-performance liquid chromatography-quadrupole/orbitrap high-resolution mass spectrometry was employed to comprehensively analyze the chemical constituents of Shengjiang Xiexin decoction. A total of 270 components, including flavonoids, coumarins, triterpenoids, alkaloids, diarylheptanoids and others, were identified or characterized. Multidrug resistance-associated protein 2 is an efflux transporter responsible for regulating drug absorption. A total of 20 characteristic components from the formula were selected to evaluate their effects on the function of multidrug resistance-associated protein 2 using the vesicular transport assay. Glycyrrhizic acid and glycyrrhetinic acid were identified as potential multidrug resistance-associated protein 2 inhibitors, while 9 flavonoid aglycones increased the uptake of the substrate [

As a well-known traditional Chinese medicine formula, the chemical constituents of Shengxian Decoction still remain unclear due to its complexity. In this study, a multidimensional strategy based on ultra-performance liquid chromatography coupled with ion mobility spectrometry quadrupole time-of-flight mass spectrometry and informatics UNIFI platform was applied to achieve rapid and comprehensive identification of the complex composition of Shengxian Decoction. Data-independent acquisition, fast data-directed analysis, and high-definition MS