Quantitative determination of multi-class bioactive constituents for quality control of Yiqi Jiangzhi Granules / 中草药·英文版

Objective: To establish a reliable and sensitive method for evaluating quality of Yiqi Jiangzhi Granules (YQJZG). Methods: Ultra performance liquid chromatography electrospray ionization tandem mass spectrometry (UPLC-ESI-MS/MS) was employed for simultaneous determination of eight marker components. Separation was performed on an AQUITY UPLC® HSS T3 column, the mobile phase consisted of acetonitrile as the organic phase and 0.1% (volume percentage) formic acid as the aqueous. Eight marker components, ginsenoside Rg1 (GRg1), ginsenoside Re (GRe), ginsenoside Rb1 (Gb1), typhaneoside (TEO), isorhamnetin-3-O-neohespeidoside (IN), hesperidin (HPD), aurantio-obtusin-6-O-β-D-glucoside (AG) and curcumin (CCM), were detected by multiple reaction monitoring (MRM) mode. The Chinese Pharmacopoeia (2020 edition) was regarded as the guidance document for this method validation. Results: The method showed good linearity (R

Pharmacokinetic comparison with different assays for simultaneous determination of cis-,trans-cefprozil diastereomers in human plasma / 药物分析学报

The purpose of this study was to compare pharmacokinetic (PK) parameters obtained using two newly developed assays,HPLC-UV and UPLC-ESI-MS/MS.Selection of assay and results obtained therefrom are very important in PK studies and can have a major impact on the PK-based clinical dose and usage settings.For this study,we developed two new methods that are most commonly used in biosample analysis and focused on PK parameters obtained from them.By HPLC-UV equipped with a Luna-C8 column using UV detector,cefprozil diastereomers were separated using water containing 2％ (V/V) acetic acid and acetonitrile as a mobile phase.By UPLC-ESI-MS/MS equipped with a HALO-C18column,cefprozil diastereomers were separated using 0.5％ (V/V) aqueous formic acid containing 5 mM ammonium-formate buffer and methanol as a mobile phase.Chromatograms showed high resolution,sensitivity,and selectivity without interference by plasma constituents.Both intra-and inter-day precisions (CV,％)were within 8.88％ for HPLC-UV and UPLC-ESI-MS/MS.Accuracy of both methods was 95.67％-107.50％.These two analytical methods satisfied the criteria of international guidance and could be successfully applied to PK study.Comparison of PK parameters between two assays confirmed that there is a dif-ference in the predicted minimum plasma concentrations at steady state,which may affect clinical dose and usage settings.Furthermore,we confirmed possible correlation between PK parameters and various biochemical parameters after oral administration of 1000 mg cefprozil to humans.

Simultaneous determination of fourteen components of Gumiganghwal-tang tablet in human plasma by UPLC-ESI-MS/MS and its application to pharmacokinetic study / 药物分析学报

Gumiganghwal-tang is a traditional herbal medicine widely used for its anti-inflammatory,analgesic,and antipyretic effects.However,the safety and efficacy of its active ingredients based on an in vivo pharmacokinetic (PK) study have yet been investigated.We have established a sensitive and accurate UPLC-ESI-MS/MS method and conducted a PK study on 14 constituents of Gumiganghwal-tang through human plasma analysis.Analytical conditions were optimized according to the physicochemical prop-erties of the 14 compounds to facilitate efficient separation and eliminate overlap or interference be-tween peaks.KINETEX-C18 and lnertsil-C8 columns were used as UPLC stationary phases,and acetonitrile and aqueous formic acid were used as mobile phases.All the analytes were quantified with a triple quadrupole mass spectrometer using electrospray ionization in multiple reaction monitoring mode.The chromatograms of 14 bioactive compounds showed excellent elution and sensitivity,and each peak was selectively separated and quantified without interference with each other or impurities.The established analytical method was based on international guidelines and was successfully used to perform PK studies of 14 herbal ingredients in humans after oral administration with Gumiganghwal-tang tablets.The oral absorption of most active components of Gumiganghwal-tang was relatively rapid and remained considerably long in the body to be quantified in plasma up to 48 h after administration.

Hypolipidemic, hipoglycemiant and antioxidant effects of Myrcia splendens (Sw) DC in an animal type 2 diabetes model induced by streptozotocin / Efectos hipolipemiante, hipoglucemiante y antioxidante de Myrcia splendens (Sw) DC en un modelo animal de diabetes tipo 2 inducido por estreptozotocina

We investigated the effects of dichloromethane extract (DME) from Myrcia splendenson alterations caused by type 2 diabetes in the blood and kidney of rats, in order to reduce side effects caused by synthetic drugs. Rats received streptozotocin (60 mg/kg),15 minutes after nicotinamide (120 mg/kg) or water. After 72 hours, the glycemic levels were evaluated to confirm diabetes and the animals received (15 days) DME (25, 50, 100 or 150 mg/Kg) or water. DME partially reversed hyperglycemia and (100 and 150 mg/kg) reversed hypertriglyceridemia. Histopathological findings elucidated that DME reduced damage to pancreatic islets. DME 150 mg/kgreversed the increases in TBA-RS, the reduction in the sulfhydryl content, 100 and 150 mg/kg increased CAT, reversed the decrease in GSH-Px and increased it activity in the blood. DME 150 mg/kg reversed CAT and GSH-Px reductions in the kidney. We believe that DME effects might be dependent on the presence of phenolic compounds.

Investigamos los efectos del extracto de diclorometano (DME)de Myrcia splendens sobre las alteraciones causadas por la diabetes tipo 2 en la sangre y los riñones de las ratas, para reducir los efectos secundarios causados por las drogas sintéticas. Las ratas recibieron estreptozotocina (60 mg/kg), 15 minutos después de la nicotinamida (120 mg/kg) o agua. Después de 72 horas, se confirmo la diabetes y los animales recibieron (15 días) DME (25, 50, 100 o 150 mg/Kg) o agua. DME revierte parcialmente la hiperglucemia y revierte la hipertrigliceridemia. DME redujo el daño a los islotes pancreáticos. DME revirtió los aumentos en TBA-RS, la reducción en el contenido de sulfhidrilo, aumentó la CAT, revirtió la disminución en GSH-Px y aumentó su actividad en la sangre. Además, DME revirtió las reducciones de CAT y GSH-Px en el riñón. Creemos que los efectos provocados por DME pueden depender de la presencia de compuestos fenólicos.

Characterization of hepatoprotective metabolites from Artemisia annua and Cleome droserifolia using HPLC/PDA/ESI/MS-MS

ABSTRACT The hepatoprotective activities of two traditionally used plants, Cleome droserifolia (Forssk.) Delile, Cleomaceae, and Artemisia annua L., Asteraceae, were recently reported. However, the biologically active metabolites responsible for this activity were not identified. The aqueous extract of C. droserifolia aerial parts, and the polar fraction of A. annua leaves were screened for their antioxidant activities using the 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) assay. The in vitro viability of HepG-2 cells treated with CCl4 and the extracts were assessed by MTT assay. The effects of the extracts on the liver enzymes and the total soluble protein in CCl4-intoxicated HepG-2 cells were investigated. An HPLC/PDA/ESI/MS-MS based analysis was carried out for extract of C. droserifolia and polar fraction of A. annua. Both exhibited pronounced free radical scavenging activities (86 and 83%, respectively). Both showed a significant increase in cell viability: 86.43% for the extract of C. droserifolia and 79.32% for polar fraction of A. annua. Only the extract of C. droserifolia (39.6 ± 5.41 and 20.4 ± 6.91 IU/dl, respectively) and polar fraction of A. annua (40.8 ± 2.14 and 24.5 ± 3.11 IU/dl, respectively) restored the levels of liver enzymes (aspartate transaminase and alanine transaminase, respectively) compared to the CCl4 intoxicated group (87.5 ± 4.34 and 34.1 ± 8.12 IU/dl, respectively) and other herbal extracts. More than fifty phenolic secondary metabolites were identified in the extracts under investigation. The significant hepatoprotective activities of both extracts seemed to be strongly connected to their content of hydroxycinnamoyl quinic acids and flavonoids.

Development And Validation Of Sensitive Lc-Esi-Ms/Ms Method For The Simultaneous Estimation Of Dapagliflozin And Saxagliptin In Human Plasma

Objective: To develop and validate a sensitive liquid chromatography-electrospray ionization-tandem mass spectrometric (LC-ESI-MS/MS) technique for the quantification of dapagliflozin and saxagliptin in plasma by linagliptin as internal standard. Methods: Chromatography was achieved on hypersil C18 (50 mmx4 mm) 5 µ analytical column with 0.1% formic acid and acetonitrile (25:75 V/V) as mobile phase at 0.7 ml/min flow rate. Dapagliflozin, saxagliptin, and linagliptin were detected at m/z 409.14/135.0, m/z 316.2/180.13 and m/z 472.54/456.21 respectively. Drugs and internal standard were extracted by LLE (liquid-liquid extraction). Results: Developed technique was validated over 0.5-1500.0 ng/ml linear concentration range for dapagliflozin and 2.00-2000.0 ng/ml for saxagliptin. This method established with intra-batch and inter-batch precision within 2.44-8.12% and 1.25-7.14 % for dapagliflozin and 1.84-7.5 % and 1.02–6.00 % for saxagliptin. This method established with intra-batch and inter-batch accuracy for dapagliflozin within 98.86-103% and 96.98-102 % respectively and for saxagliptin within 98.05-109.06 % and 97.00-104.00 % respectively. Conclusion: Both dapagliflozin and saxagliptin were stable during three freeze-thaw cycles, long term and bench-top stability studies. The developed method was useful for the routine analysis of dapagliflozin and saxagliptin simultaneously in plasma samples.

Chemical constituents from Rhamnus heterophylla / 中草药

Objective: To investigate the chemical constituents from Rhamnus heterophylla. Methods: Multiple chromatographic separation techniques including silica gel, Sephadex LH-20 gel and MCI gel were employed to isolate and purify the compounds. Their structures were identified by means of the nuclear magnetic resonance (NMR) and physicochemical properties. The chemical compositions were quickly analyzed by HPLC-DAD-ESI-MS/MS and scanned in negative ions. Results: These compounds were isolated and determined as cis-aloeemodin bianthrone (1), trans-aloeemodin bianthrone (2), emodin-8-O-rhamnoside (3), citreorosein (4), emodin (5), chrysophanol (6), physcion (7), kaempferol (8), luteolin (9), and quercetin (10). In addition to compounds 5, 8, the other compounds are isolated from R. heterophylla for the first time, and the compound 3 is isolated from the genus Rhamnus for the first time. 28 Compounds were speculated via comparing MS data (detected mass and MS2 fragment ions) and coupled with related literature, including three hydroxybenzoic acids, eight anthraquinones and 17 flavonoids. Conclusion: The analysis of chemical constituents from R. heterophylla could provide the references for the study on pharmacodynamic material basis and reasonable application and development.

Antioxidant activities in vitro and components analysis of methanol extract of Actinidia arguta by HPLC-DAD-ESI-MS/MS / 中草药

Objective: To investigate and analyze antioxidant activities in vitro and the active ingredients of the methanol extract of Actinidia arguta. Methods: In this study, antioxidant activities of extract of A. arguta were carried out by using DPPH and ABTS radical scavenging assays in vitro. Qualitative analysis of major active components was performed by HPLC-DAD-ESI-MS/MS. Results: Extract of A. arguta had good scavenging effect on DPPH and ABTS free radical in vitro, and the EC50 values of scavenging effect of extract of A. arguta on DPPH and ABTS free radical were (26.275 ± 1.464) and (29.826 ± 1.309) mg/mL, respectively. On the basis of UV and mass spectral analysis, a total of 19 chemical compositions were preliminarily identified. Conclusion: extract of A. arguta has good antioxidant activity in vitro, and polyhydroxyl and unsaturated double bonds are the main active constituents.

Simultaneous determination of nine bioactive components in Bazhen Yimu Pills by HPLC-ESI-MS/MS / 中草药

Objective To develop and validate a high performance liquid chromatography coupled with electrospray tandem mass spectrometry (HPLC-ESI-MS/MS) method for simultaneously qualitative and quantitative determination of nine major bioactive components (stachydrine hydrochloride, leonurine hydrochloride, paeoniflorin, ferulic acid, liquiritin, lobetyolin, verbascoside, atracylenolide I, and polyporenic acid C) in Bazhen Yimu Pills (BYP). Methods The chromatographic separation was performed on an Waters Atlantis T3 column (150 mm × 4.6 mm, 3.0 μm) with a gradient elution of methanol and 0.1% formic acid in water at a flow rate of 0.5 mL/min, and the injection volume was 10 μL. The nine major bioactive components were detected using an electrospray ionization source in negative ionization mode (ESI-) and quantified by multiple reaction monitor (MRM) scanning at the same time. Results The linear ranges of stachydrine hydrochloride, leonurine hydrochloride, paeoniflorin, ferulic acid, liquiritin, lobetyolin, verbascoside, atracylenolide I, and polyporenic acid C were 0.04-40.00 μg/mL (r = 0.999 2), 0.04-40.00 μg/mL (r = 0.999 3), 1.0-100.0 μg/mL (r = 0.999 1), 0.2-20.0 μg/mL (r = 0.999 6), 0.2-20.0 μg/mL (r = 0.997 5), 0.05-5.00 μg/mL (r = 0.999 4), 0.1-10.0 μg/mL (r = 0.999 4), 0.1-10.0 μg/mL (r = 0.999 2), 0.1-10.0 μg/mL (r = 0.999 2), and the average recoveries were 99.7% (RSD = 0.52%), 98.1% (RSD = 0.64%), 98.5% (RSD = 1.08%), 101.5% (RSD = 1.12%), 99.5% (RSD = 0.39%), 98.4% (RSD = 0.74%), 99.1% (RSD = 0.91%), 101.2% (RSD = 0.54%), and 100.1% (RSD = 0.47%), respectively. The content of nine batches of the nine major bioactive components were 0.423-0.752, 0.505-0.722, 0.613-1.300, 0.102-0.184, 0.195-0.255, 0.021-0.035, 0.034-0.072, 0.039-0.063, and 0.051-0.095 mg/g, respectively. Conclusion The developed method is simple, specific, and sensitive, and it can be applied for the determination of nine major bioactive components and the quality control of BYP collected from different production batches.

Composition analysis and antioxidant activities of the Rhus typhina L. stem / 药物分析学报

The present investigation reports the chemical composition of the Rhus typhina L. stem identified via mass spectrometry and NMR as gallic acid, 1-O-galloyl-β-D-glucose, tryptophan, scopolin, methyl gallate, fustin, quercetin, rutin, and 1,2,3,4,6-penta-O-galloyl-β-D-glucose. The antioxidant properties and the chemical composition contents of the R. typhina L. stem grown in different regions in China were de-termined. To determine the antioxidant activity, a total phenolic content analysis, 2, 2-diphenyl-1-pi-crylhydrazyl radical scavenging activity assay, ferric reducing antioxidant power assay, andβ-carotene linoleic acid model system were conducted. The results showed that the Rhus typhina L. stem possessed high antioxidant capacities due to its high phenolic content. The contents of the nine isolated compounds were determined by UPLC-ESI-MS/MS. The calibration curves of the nine isolated compounds were linear within the concentration range and the average recoveries were high. The result showed that 1-O-galloyl-β-D-glucose, gallic acid, methyl gallate, and 1,2,3,4,6-penta-O-galloyl-β-D-glucose could be the compounds mainly responsible for the antioxidant capacity of the R. typhina L. stem. This reveals that the R. typhina L. stem is a good source of antioxidants.

Survey on pesticide use in Crataegi Fructus and analysis of pesticide residues based on LC-ESI-MS/MS / 中国中药杂志

In order to study the pesticide residues of the medicinal Crataegi Fructus,this study aims to establish an analysis method for pesticide residues( mainly containing insecticides and fungicides) suitable for the actual situation of medicinal Crataegi Fructus based on the survey of the pesticides of the Crataegi Fructus base,combined with the blind screening results of the LC-ESI-MS/MS pesticide screening platform established by the research team in the early stage. Then,the pesticide residues in medicinal Crataegi Fructus from Shandong,Hebei,Henan,Shanxi,and Liaoning( main cultivation areas) were analyzed. The samples were pretreated by the modified Qu ECh ERS method,i.e.,extracted with acetonitrile-water( 9 ∶1),purified by PSA,C_(18),GCB,silica gel. The detection of pesticides was performed by LC-MS/MS. The ion source was ESI with positive scanning mode,and the linearity of 11 kinds of pesticides in the range of 5-300 μg·kg~(-1) was acceptable( R~2>0. 996 9). All the recoveries of pesticides were within 70. 02%~(-1)12. 0% in the low,medium and high levels,with RSD≤17%. The results showed that the detection rate of carbendazim,chlorpyrifos and difenoconazole is 79%,82%,56%,respectively. Besides,the prohibition pesticide carbofuran were detected in some of the batches,indicating the security risk. This study provides methodological references and basic data for risk assessment of Crataegi Fructus and government regulation.

Simultaneous determination of nine bioactive components in Sishen Pills by HPLC-ESI-MS/MS / 中草药

Objective To develop and validate an high performance liquid chromatography coupled with electrospray tandem mass spectrometry (HPLC-ESI-MS/MS) method for simultaneously qualitative and quantitative determination of nine major bioactive components (deoxyschizandrin, γ-schizandrin, schizandrin, schizandrol B, schisantherin A, psoralen, isopsoralen, evodiamine, and rutaecarpine) in Sishen Pills. Methods The chromatographic separation was performed on an Agilent Zorbax Eclipse Plus C18 column (100 mm × 4.6mm, 3.5 μm) with a gradient elution of methanol and 0.1% formic acid in water at a flow rate of 0.4 mL/min, and the injection volume was 20 μL. The nine major bioactive components were detected using an electrospray ionization source in positive ionization mode (ESI+) and quantified by multiple reaction monitor (MRM) scanning at the same time. Results The linear ranges of deoxyschizandrin, γ-schizandrin, schizandrin, schizandrol B, schisantherin A, psoralen, isopsoralen, evodiamine, and rutaecarpine were 8.50-850.00 ng/mL (r = 0.999 7), 1.32-132.00 ng/mL (r = 0.997 4), 9.60-960.00 ng/mL (r = 0.999 8), 12.00-1 200.00 ng/mL (r = 0.999 3), 11.50-1 150.00 ng/mL (r = 0.997 9), 21.70-2 170.00 ng/mL (r = 0.999 7), 23.80-2 380.00 ng/mL (r = 0.999 6), 10.70-1 070.00 ng/mL (r = 0.999 5), 8.54-854.00 ng/mL (r = 0.998 0), and the average recoveries were 98.3% (RSD = 2.21%), 100.3% (RSD = 1.78%), 99.2% (RSD = 2.19%), 100.4% (RSD = 2.23%), 99.1% (RSD = 2.18%), 97.7% (RSD = 3.03%), 99.0% (RSD = 2.51%), 98.9% (RSD = 2.72%), and 100.3% (RSD = 2.10%), respectively. The contents of eight batches of the nine major bioactive components were 67.6-425.6, 0-131.5, 2.1-258.0, 0-71.2, 23.2-678.8, 806.4-1310.8, 718.5-1293.7, 11.5-123.2, and 10.9-62.4 μg/g, respectively. Conclusion The developed method is simple, specific, and sensitive, and it can be applied for the determination of nine major bioactive components and the quality control of Sishen Pills collected from different production batches.

Mass spectrometry guided strategy based on feature fragment ions for guided-separation on quinoline alkaloids from root barks of Dictamnus dasycarpus / 中国中药杂志

The root bark of Dictamnus dasycarpus is one of common traditional Chinese medicines (TCMs). Quinoline alkaloids are one of the main active substances in this TCM and possess many biological activities including anti-titumor, anti-inflammation, anti-bacteria, anti-oxidation, and anti-platelet aggregation activities. In this study, eight quinoline alkaloids 1-8 were firstly separated from the root barks of D. dasycarpus. It was difficult to isolate more quinoline alkaloids from the remaining fraction 8 in D. dasycarpus by this conventional chemical separation, so the target analysis method combined LC-MS guided-separation of quinoline alkaloids from fraction 8 was established. MS/MS fragmentation patterns of eight quinoline alkaloids reference standard compounds 1-8 were studied by ultra-performance liquid chromatography-electrospary ionization-mass spectrometry (UPLC-ESI-MS/MS). Based on the feature fragment ion 200, the parent ion scan mode was established for the target analysis of quinoline alkaloids in fraction 8. Finally, 8-methoxyflindersine (9) and N-metilatanina (10) were discovered and isolated quickly from fraction 8 guided by LC-MS, and their structures were identified by NMR and MS. Among them, compound 10 was isolated from the genus Dictamnus for the first time. These results indicated that this method is not only quick and sensitive for analyzing the quinoline alkaloids, but also to effectively guided-separate this kind of alkaloids in the root barks of D. dasycarpus.

Sensitive and rapid determination of amantadine without derivatization in human plasma by LC–MS/MS for a bioequivalence study / 药物分析学报

A highly sensitive, rapid and rugged liquid chromatography-tandem mass spectrometry (LC-ESI-MS/MS) method was developed for reliable estimation of amantadine (AMD), an antiviral drug in human plasma. The analyte and internal standard (IS), amantadine-d6 (AMD-d6), were extracted from 200 μL plasma by solid phase extraction on Phenomenex Strata-X-C 33 μ cartridges. Chromatography was performed on Synergi? Hydro-RP C18 (150 mm × 4.6 mm, 4 μm) analytical column using a mixture of acetonitrile and 10 mM ammonium formate, pH 3.0 (80:20, v/v) as the mobile phase. Detection and quantitation was done by multiple reaction monitoring in the positive ionization mode for AMD (m/z 152.1 → 135.1) and IS (m/z 158.0 → 141.1) on a triple quadrupole mass spectrometer. The assay was linear in the concentration range of 0.50–500 ng/mL with correlation coefficient (r2) ≥ 0.9969. The limit of detection of the method was 0.18 ng/mL. The intra-batch and inter-batch precisions were ≤ 5.42% and the accuracy varied from 98.47% to 105.72%. The extraction recovery of amantadine was precise and quantitative in the range of 97.89%–100.28%. IS-normalized matrix factors for amantadine varied from 0.981 to 1.012. The stability of AMD in whole blood and plasma was evaluated under different conditions. The developed method was successfully applied for a bioequivalence study with 100 mg of AMD in 32 healthy volunteers. The re-producibility of the assay was determined by reanalysis of 134 subject samples.

Qualitative and quantitative analysis of the phenolic content of Connarus var. angustifolius, Cecropia obtusa, Cecropia palmata and Mansoa alliacea based on HPLC-DAD and UHPLC-ESI-MS/MS

ABSTRACT The phenolic content of the medicinal species Connarus perrottetti var. angustifolius Radlk., Connaraceae, Cecropia obtuse Trécul, Cecropia palmata Willd., Urticaceae; and Mansoa alliacea (Lam.) A.H.Gentry, Bignoniaceae, collected in three different years was evaluated. Plant infusions and hydroalcoholic, butanol and ethyl acetate extracts were analyzed by high-performance liquid chromatography with diode array detection. In order to endorse these results, analysis by electrospray mass spectrometry was also performed. Were identified: gallic acid, catechin, caffeic acid, ferulic acid, rutin, quercitrin and resveratrol. C. perrottetti showed greater diversity of polyphenols. M. alliacea had the higher concentration of caffeic acid even though it was found in all species. Catechin was the major antioxidant, but was not detected in M. alliacea. However, we discuss the popular use of these species, as well as their phenolic constitution and the interannual distribution of phenolic compounds.

Identification of C-geranylated flavonoids from Paulownia catalpifolia Gong Tong fruits by HPLC-DAD-ESI-MS/MS and their anti-aging effects on 2BS cells induced by HO / 中国天然药物

The fruits of Paulownia catalpifolia Gong Tong are used as a Chinese folk herbal medicine for the treatment of enteritis, tonsillitis, bronchitis, and dysentery, etc. Our previous study has identified new C-geranylated flavanones with obvious anti-proliferative effects in lung cancer A549 cells. In the present study, a new C-geranylated flavone, paucatalinone C (1) and five known C-geranylated flavanones (2-6) were isolated. In addition, a total of 34 C-geranylated flavonoids were detected by HPLC-DAD-ESI-MS/MS coupling techniques from the CHCl extract of P. catalpifolia. Futhermore, anti-aging effects of isolated compounds were evaluated in vitro with premature senescent 2BS cells induced by HO. Phytochemical results indicated that P. catalpifolia was a natural resource of abundant C-geranylated flavonoids. Diplacone (3) and paucatalinone A (5) were the potent anti-aging agents in the premature senescent 2BS cells induced by HO and the C-geranyl substituent may be an important factor because of its lipophilic character.

A stability-indicating LC–MS/MS method for zidovudine: Identification, characterization and toxicity prediction of two major acid degradation products / 药物分析学报

Zidvovudine (AZT) is a nucleoside analogue reverse transcriptase inhibitor (NRTI), a class of anti-retroviral drug. A stability-indicating assay method for AZT was developed in line with ICH guideline. Successful separation of AZT and its degradation products was achieved by gradient elution mode on reverse phase C18 column using 10 mM ammonium acetate: acetonitrile as the mobile phase at 0.8 mL/min flow rate, 25 μL injection volume, 30 °C column temperature and 285 nm detection wavelength. Two major acid degradation products were identified and characterized by liquid chromatography–electrospray ionization mass spectro-metry (LC–ESI/MS/MS) and accurate mass measurements. The probable mechanisms for the formation of degradation products were identified based on a comparison of the fragmentation pattern of the [M + H] + ions of AZT and its degradation products. One of the degradation products, DP-1, was isolated by semi-preparative high performance liquid chromatography (HPLC) using Waters XBridge Prep C18 (250 mm×10 mm, 5 μm). Degradation products showed higher toxicity compared to the drug in some models assessed by TOPKAT software. The method validation was performed with respect to robustness, specificity, linearity, precision and accuracy as per ICH guideline Q2 (R1).

Evaluate effects of different drying methods on quality of Tianshu capsule on substance basis / 中国中药杂志

To investigate the effect of hot air circulation drying and spray drying on the quality of Tianshu capsule from the view point of chemical compositions. UPLC-DAD was used to establish the fingerprint of Tianshu capsules for the first time, and the main chemical constituents were identified by UPLC-Q-TOF-MS/MS. A total of 62 compounds were identified in this method, 21 of which were reported in Tianshu capsules for the first time. The results showed that there were no significant differences in the identification of the chemical constituents types between these two methods, but the contents of some constituents were different. The common patterns generated by the 10 batches of hot air cycle drying samples were used as the control fingerprint, and the similarity of the spray drying samples fingerprints was 0.877, with high similarity of the fingerprints between these two methods. UPLC-DAD combined with UPLC-Q-TOF-MS/MS technology was used for the first time to evaluate the chemical constituents of Tianshu capsule rapidly, comprehensively and accurately, providing technical support for the quality evaluation of Tianshu capsule.

Simultaneous Determination of Carbamazepine and Phenobarbital in Human Plasma by UPLC-MS/MS / 中国药师

Objective: To establish an ultra performance liquid chromatography-tandem quadrupole mass spectrometry ( UPLC-MS/MS) method to determine the concentration of carbamazepine and phenobarbital in human plasma, and apply in the clinical moni-toring. Methods:Diazepam was used as the internal standard, and the samples were precipitated by acetonitrile. An ACQUITY UPL-C? BEH C18 (50 mm × 2. 1 mm, 1. 7 μm) column was used as the stationary phase at 40℃ with a Waters XEVO TQD. The mobile phase consisted of acetonitrile (containing 10 mmol·L-1 ammonium formate) and water (containing 10 mmol·L-1 ammonium for-mate and 0. 1% formic acid) with gradient elution pumped at a flow rate of 0. 4 ml·min-1 . ESI was applied and the samples were scanning analyzed by positive ion multi-reaction monitoring mode. The plasma was precipitated by 200 μl acetonitrile and centrifugated at 12 000 × g for 10 min and tranfer it into an Ep tube. The sample size was 20 μl. Results:The retention time of carbamazepine was 1. 23 min. Excellent linear calibration curves of carbamazepine were obtained within the concentration range of 0. 25-25μg·ml-1(r=0. 999 7). The lower limit of quantification of carbamazepine was 0. 01 μg·ml-1. The retention time of phenobarbital was 1. 11 min. Excellent linear calibration curves of carbamazepine were obtained within the concentration range of 0. 5-50 μg·ml-1(r=0. 999 6). The lower limit of quantification of carbamazepine was 0. 05 μg·ml-1. The recovery of three concentrations of carbamazepine was (82. 1 ± 6. 83)%, (82. 91 ± 4. 3)% and (84. 35 ± 3. 09)%, and the recovery of three concentrations of phenobarbital was (84. 27 ± 6. 91)%, (84. 32 ± 7. 74)% and (89. 07 ± 6. 24)%, respectively. The intra- and inter-day RSDs were all less than 10%. There were no endogenous substances existing in the incubation system, therefore, there was no interference with the determination. Conclu-sion:The simple, accurate and rapid method is suitable for the determination of carbamazepine and phenobarbital in human plasma, which can contribute greatly to the therapeutic drug monitoring service for patients.

Pharmacokinetic Study on Luteolin and Cynaroside in Rats / 中国药房

OBJECTIVE:To establish the method for pharmacokinetic study of luteolin and cynaroside in rats and to determine pharmacokinetic parameters. METHODS:16 SD rats were randomly divided into luteolin group (sublingual iv,1.34 mg/kg) and cynaroside group(sublingual iv,0.64 mg/kg). 0.5 ml blood were collected before administration and 0,15,30 min and 1,2,3,4,6, 8,12,24,48 h after administration respectively to prepare plasma. UPLC-TQ-MS was adopted to determine plasma concentration, and pharmacokinetic parameters were calculated. A CORTECSTM UPLC? C18(100 mm×2.1 mm,1.6 μm)column was used with mobile phase consisted of acetonitrile-water (containing 0.1% formic acid) at a flow rate of 0.4 ml/min,the column temperature was set at 40 ℃,and quercetin was used as internal standard. RESULTS:The linear range of luteolin and cynaroside were 2.5-500 ng/ml (r=0.998 2) and 10-2 500 ng/ml (r=0.993 5). The lowest quantitation limits were 1 and 2.5 ng/ml,and extraction were 70.75%-87.72% and 75.40%-91.18%(n=6);RSD of inter-day and intra-day were all lower than 10%(n=3). Pharmacokinetic parameters as t1/2 were (1.88 ± 0.32) and (1.57 ± 0.08) h;CL were (0.77 ± 0.18) and (0.06 ± 0.01) L/(h·kg);AUC0-6 h were (189.60±40.04)and(1 093.14±187.36)ng·h/ml;AUC0-∞ were(195.18±38.37)and(1 097.11±188.07)ng·h/ml. CONCLU-SIONS:The method can be used for pharmacokinetic study of luteolin and cynaroside in rats,and the pharmacokinetics of them in rats are in line with two-compartment model.