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Journal of Psychedelic Studies
Authors:
Giordano Novak Rossi
,
Eduardo José Crevelin
,
Gabriela de Oliveira Silveira
,
Maria Eugênia Costa Queiroz
,
Mauricio Yonamine
,
Jaime Eduardo Cecilio Hallak
, and
Rafael Guimarães dos Santos

analysis. Ultra performance liquid chromatography–electrospray ionization–tandem mass spectrometry (UPLC-ESI-MS/MS) analysis Analyses were performed using a Waters UPLC Acquity System coupled to a Quattro Premier tandem MS

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), orthophosphoric acid (88% w/w ACS grade), Acetonitrile (Merck-HPLC grade), Hydrochloric acid 36% (AR grade), and Water (Milli-Q grade). Instrumentation and methodologies Analytical UPLC chromatographic conditions Chromatographic separation was performed on Water

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modern forms to ensure the consistency of clinical efficacy with the traditional formula. An integrated strategy was developed by coupling ultra-performance liquid chromatography (UPLC), quadrupole time-of-flight (Q-TOF) with hybrid triple

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goats ( El-Hewaity et al . , 2014 ). Acetonitrile, methanol and ammonium acetate for UPLC were purchased from Sigma-Aldrich (St. Louis, MO, USA). The product was approved for the treatment of pneumonia in cattle and pigs as well as mastitis

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Acta Chromatographica
Authors:
Xiaoyan Zhang
,
Jie Liu
,
Wenbo Sun
,
Xiangchun Shen
,
Xiaojian Gong
,
Cong Wang
,
Yan Liang
, and
Wei Zhou

biologically tested sample we want for UPLC-MS analysis. Hemostatic activity test According to the previously-scheduled plasma collection point, SD rats from each group were given orally to corresponding drugs, and then anticoagulated blood was collected

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Summary

A simple and rapid method, using online ultraperformance liquid chromatography with photodiode array detection and electrospray ionization mass spectrometry (UPLC-PDA-eλ-ESI-MS/MS), was developed for the in-depth analysis of 50 batches Radix et Rhizoma Rhei. The analysis was performed on a UPLC BEH C18 column using a gradient elution system. Baseline separation could be achieved in less than 7.5 min. At the same time, on the basis of the 50 batches of samples collected from representative cultivated regions, a novel chromatographic fingerprint was devised by UPLC-PDA, in which 27 common peaks were detected and identified by the developed UPLC-MS/MS method step by step according to fragmentation mechanisms, MS/MS data, standards, and relevant literature. Many active components gave prominent [M - H] ions in the ESI mass spectra. These components include anthraquinones, sennosides, stilbenes, glucose gallates, naphthalenes, and catechins. Furthermore, based on the information of these Radix et Rhizoma Rhei components, and further combined with discriminant analysis, a novel discriminant analysis equation (DAE) was established for the quality control of Radix et Rhizoma Rhei for the first time.

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Summary

A new method using ultra-performance liquid chromatography (UPLC) in combination with tandem mass spectrometry and a multiple reaction monitoring mode (UPLC-MS/MS-MRM) was developed for simultaneous quantitative determination of anthraquinone derivatives in Radix et Rhizoma Rhei-based medicines. A multi-mode electrospray/chemical ionization (ESCI) and negative ion mode with [M-H] and its fragments under collision-activated conditions were employed in MS/MS-MRM. The quantitative method was validated and applied to simultaneous determination of anthraquinone derivatives in 21 Radix et Rhizoma Rhei-based medicines. The limits of quantification were in the range of 3.90–9.09 ng mL−1. Average recoveries were between 95.5% and 99.8% with relative standard deviations from 1.8% to 5.3%.

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Compound danshen preparations (CDPs) are used clinically for the treatment of cardiovascular and cerebrovascular diseases. By using the quantitative analysis of multi-components by single-marker (QAMS) method, sixteen compounds (danshensu, protocatechuic acid, protocatechuicaldehyde, caffeic acid, rosmarinic acid, lithospermic acid, notoginsenoside R1, salvianolic acid B, ginsenoside Rg1, ginsenoside Re, salvianolic acid A, salvianolic acid C, ginsenoside Rb1, ginsenoside Rd, cryptotanshinone, and tanshinone IIA were quantified on an ACQUITY ultraperformance liquid chromatography (UPLC) HSS T3 column (2.1 × 100 mm, 1.8 μm) with the mobile phase consisting of 0.1% formic acid aqueous solution (A) and acetonitrile (B) using a gradient elution at the flow rate of 0.30 mL/min in 30 min at 30°C, which was also validated by UPLC-diode array detection (DAD) and UPLC-electrospray ionization multistage/mass spectrometry (ESI-MS/MS) for assuring the feasibility and accuracy. Tested by robustness experiment under slightly changeable conditions, the stability of relative correction factor (RCF) proved to be stable, with RSDs below 5.69%, except for notoginsenoside R1 with relative standard deviation (RSD) 7.83%. This reliable and convenient QAMS method resolved the problem of standard substance insufficiency and improved the quality assessment of preparations consisting of complex compounds with different chemical structures, such as CDPs.

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The aim of this study was to compare the antioxidant activity of crude extracts of differing polarities of the fruits of Chaenomeles speciosa (Sweet) Nakai. The antioxidant compositions of the extracts were analyzed qualitatively and quantitatively, respectively. The 75% ethanol extract of the dried fruits was fractionated by sequential extraction using petroleum ether, ethyl acetate, and n-butyl alcohol. The antioxidant effectiveness of the components of differing polarities was examined by 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging method and compared with two reference substances: ascorbic acid and butylated hydroxytoluene (BHT). The total phenolic content of the extracts was analyzed using the Folin–Ciocalteu method and expressed as gallic acid equivalents. The active compounds were analyzed by thin-layer chromatography (TLC)–bioautography and ultra-performance liquid chromatography (UPLC). The order of antioxidant capacities of various solvent extracts from the fruit of C. speciosa was found to be ethyl acetate ≥ n-butyl alcohol > petroleum ether. The ethyl acetate extract was more active than the reference substances ascorbic acid and BHT. The radical-scavenging capacity of the extracts decreased as the total phenolic content decreased. TLC–bioautography revealed that the ethyl acetate extract contained many antioxidant spots that can remove DPPH radical, and protocatechuic acid and chlorogenic acid were the major antioxidant components. UPLC analysis confirmed that protocatechuic acid and chlorogenic acid were mainly distributed in the ethyl acetate fraction. The study demonstrated that the ethyl acetate extract had excellent antioxidant capacity. The total phenolic, protocatechuic acid, and chlorogenic acid contents of this extract were higher than those of the other two solvent extracts. These results showed that the ethyl acetate extract from the fruit of C. speciosa could be considered as a potential source of natural antioxidant agent.

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Two chromatographic methods were developed for the simultaneous determination of paracetamol, pamabrom, and pyrilamine maleate in bulk and combined pharmaceutical dosage form. The first method is an ultra-performance liquid chromatographic (UPLC) method, in which separation was carried out by gradient elution using C18 column and a mobile phase composed of solution A (acetonitrile) and solution B (phosphate buffer) (pH 3.5). The elution started with 20% (by volume) acetonitrile ramped up linearly to 100% in 2 min, then kept constant till the end of the run at a flow rate of 1.5 mL min−1 and ultraviolet (UV) detection at 277 nm. The second method depends on the densitometric determination of thin-layer chromatograms of the three drugs. Separation was carried out at 275 nm using chloroform‒acetonitrile (15:35, v/v) as the mobile phase. The proposed methods were validated according to the International Conference on Harmonisation (ICH) guidelines. Beer’s law was obeyed in the range of 5–100 μg mL−1 for paracetamol and 0.5–20 μg mL−1 for pamabrom and pyrilamine maleate, respectively, with mean recoveries of 98.40‒100.32% ± 0.551‒0.771 for the UPLC method. Linearity of the thin-layer chromatographic method was achieved in the range of 10‒280, 5‒45, and 1–20 ng per spot of the three drugs with mean recoveries of 98.75‒100.30% ± 0.971‒1.061, respectively. The two methods were successfully applied for the simultaneous determination of the cited drugs in their laboratory-prepared mixtures and pharmaceutical dosage form with good accuracy and precision. The results obtained were compared with those of the reported method and found to be in good agreement.

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