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Abstract  

A set of proton optical potential parameters was obtained on56Fe from threshold to 65.0 MeV based on the available experimental data, and the excitation functions and energy spectra were evaluated and calculated for56Fe,57Fe(p,n), (p,p1), (p,α), (p,3He), (p,d), (p,t), (p,2n), (p,np+pn), (p,nα+αn), (p,2p) and (p,3n) reactions from respective threshold up to 30.0 MeV. There are good agreements between the experimental data and the calculated data.

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Abstract  

Monoclonal antibody 3H11 was labelled with99mTc by modified Schwartz method. The antibody was incubated in a glass test tube at room temperature for 30min with a 1000-fold molar excess of 2-mercaptoethanol. The mean labelling efficiency of 3H11 with99mTc was more than 95%. The immuonreactivity of99mTc-3H11 was more than 80% by ELISA's method. Competetion results in vitro and HPLC analysis showed that99mTc was combined at the high affinity sites of antibody. The biodistribution in nude mice bearing 823 gastric cancer xenograpfts showed that the radioactivity in tumor at 24h postinjection was the highest except for that in kidney. The tumor uptake was 8.98±2.42% i.d/g. The ratio of tumor to blood was over 1.5 and that of tumor to liver was more than 2.5 at 24h post-injection. The tumor was clearly imaged at 22h postinjection. The inital clinical results showed that99mTc-3H11 was stable in vivo and was good located at the lesion sites.

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Ionic liquid-based ultrasonic-assisted extraction (ILUAE) was successfully applied to the extraction of the four chromones (prim-O-glucosylcimifugin, cimifugin, 5-O-methylvisammioside, and sec-O-glucosylhamaudol) from Saposhnikovia divaricata (Radix Saposhnikoviae) for the first time. A series of l-alkyl-3-methylimidazolium ILs differing in anion and cation compositions was evaluated for extraction efficiency, and [C3MIM]Br was selected as the optimal solvent. In addition, ultrasound extraction parameters were optimized, and the chromones were directly quantified and analyzed by rapid resolution liquid chromatography-electrospray ionization/mass spectrometry (RRLC-ESI/MS). The optimal conditions were as follows: 0.4 M concentration of [C3MIM]Br, 20:1 solvent to solid ratio, and ultrasonic time, temperature, and frequency of 5 min, 40 °C, and 50 kHz, respectively. This approach obtained the highest extraction yield of 10.188 ± 0.473 mg g−1 for total chromones. Compared with regular UAE, the proposed approach exhibited a higher efficiency (61.56% increase) and shorter extraction time (nine times shorter). Also, ILUAE was an efficient, rapid, and simple sample preparation technique for extraction of chromones, and the established RRLC-DAD method could serve as a rapid and effective technique for extracting chromones from Radix Saposhnikoviae.

Open access

Abstract

Ivosidenib (AG-120) is an unlisted, but estimated to be valid, oral inhibitor for isocitrate dehydrogenase 1 (IDH1) in the phase Ⅰ study of IDH1-mutated acute myeloid leukemia (AML) patients. This paper presents the investigation and validation of a rapid, effective, qualitative and quantitative determination method of ivosidenib in rat plasma by ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS). The samples were treated using acetonitrile precipitation to remove protein influence. Then, the supernatant was extracted to analyze plasma concentration traits. In the UPLC system, acetonitrile and water containing 0.1% formic acid were selected as a cosolvent mobile phase, applying a gradient elution to isolate compounds in a C18 column. Mass detections were performed on a triple quadruple mass spectrometer in positive ion mode. Electroshock characteristic fragment ionization was used for m/z 583.95→214.53 for ivosidenib for quantitative determination, m/z 583.95→186.6 for qualitative determination, and m/z 492.06→354.55 for IS. The selectivity, linearity, stability, accuracy and precision were verified by reaching the guideline criteria from European Medicine Agency (EMA) and the Food and Drug Administration (FDA). The calibration curve was linear over the concentration range of 2–2,000 ng mL−1 for ivosidenib in rat plasma with a lower limit of quantification (LLOQ) of at least 2 ng mL−1. Additionally, there was no distinct matrix effect or carry-over phenomenon. The method was successfully established and applied to separate ivosidenib from plasma, with the entire analytical process being performed within 3 min for each sample, which shows high-efficiency and convenience for further studies of ivosidenib.

Open access

Abstract

Based on chromatographic fingerprinting combined with quantitative analysis on characteristic chemical constituents as well as hierarchical cluster analysis, an easy and sensitive approach utilizing high performance liquid chromatography (HPLC) was developed for the identification and quality evaluation of Rutongshu oral liquid (ROL). What is more, nontargeted metabolomic analysis was conducted to gain a global view in terms of its chemical profile. In this study, 16 peaks from different batches (S1–S10) of ROL samples produced by Taihe Hospital of Chinese Medicine were selected as common peaks for the evaluation of their similarity whose values of all tested 10 batches exceeded 0.90 when compared with the control fingerprints. Meanwhile, simultaneous quantification of five markers in the oral solution, including albiflorin, paeoniflorin, chlorogenic acid, quercetin and ferulic acid was performed, and standard curves established for respective reference substances showed good regression in the linear range (r 2 > 0.999) with recoveries in the range of 98.96–102.35%. The ultra-high performance liquid chromatography (UHPLC) combined with Orbitrap Exploris 120 mass spectrometer resulted in 88 identified compounds. The results of validation showed that the established method was reproducible, precise and stable. This study offers an effective, dependable and useful approach for the systematic evaluation of the hospital formulation ROL.

Open access
Journal of Radioanalytical and Nuclear Chemistry
Authors:
Gu-Cai Li
,
Duan-Zhi Yin
,
Deng-Feng Cheng
,
Ming-Qiang Zheng
,
Yan-Jiang Han
,
Han-Chen Cai
,
Jiao-Yun Xia
,
Sheng Liang
,
Wan-Bang Xu
, and
Yong-Xian Wang

Abstract  

3-(4-[18F]fluorobenzyl)-8-hydroxy-1,2,3,4-tetrahydrochromeno[3,4-c]pyridin-5-one ([18F]FHTP) was in vitro and in vivo evaluated as a putative dopamine D4 receptor radioligand. Its inhibition constant (K i ) for cloned human dopamine D4.2 receptor was determined to be 2.9 nM and it displayed a 2000-fold D4-selectivity over the D2long subtype. Its partition coefficient (logP) was measured to be 1.11. Biodistribution, blocking distribution and metabolism studies in rats demonstrated that the specific distribution of [18F]FHTP in brain regions, suggesting that [18F]FHTP may be a suitable PET imaging agent for in vivo studies of the dopamine D4 receptor.

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Journal of Thermal Analysis and Calorimetry
Authors:
Li-Fang Song
,
Chun-Hong Jiang
,
Jian Zhang
,
Li-Xian Sun
,
Fen Xu
,
Wan-Sheng You
,
Yi Zhao
,
Zhi-Heng Zhang
,
Mei-Han Wang
,
Yutake Sawada
,
Zhong Cao
, and
Ju-Lan Zeng

Abstract  

A novel metal-organic frameworks [Cu2(OH)(2,2′-bpy)2(BTC) · 2H2O]n (CuMOF, BTC = benzene-1,3,5-tricarboxylic acid, 2,2′-bpy = 2,2′-bipyridine) has been synthesized hydrothermally and characterized by single crystal XRD, FT-IR spectra. The low-temperature molar heat capacities were measured by temperature modulated differential scanning calorimetry (TMDSC) for the first time. The thermodynamic parameters such as entropy and enthalpy relative to reference temperature 298.15 K were derived based on the above molar heat capacity data. Moreover, the thermal stability and the decomposition mechanism of CuMOF were investigated by TG-MS (thermogravimetry-mass spectrometer). A four-stage mass loss was observed in the TG curve. MS curve indicated that the gas products for oxidative degradation of CuMOF were H2O, CO2, NO and NO2.

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Abstract

Atractylodis macrocephalae rhizome (AMR) belongs to medicine food homology. Its' clinical application of invigorating the spleen-stomach of AMR was applied to various diseases. In this research, a UPLC-QTOF-MS method was developed for qualitative and quantitative analysis of AMR, simultaneously. A Waters Acquity BEH C18 column (2.1 mm × 100 mm, 1.7 μm particle size) was used for separation of AMR multi-components. The column was eluted with a mobile phase of 0.1% formic acid-water and 0.1% formic acid-acetonitrile. Electron spray ionization with positive-ion mode and external standard method was utilized for quantifying the nine analytes in AMR. Constituents of AMR were scanned by UPLC-QTOF-MS and then identified by mass fragments and chromatographic information compared with the published literature and reference standards. Under positive mode, a total of 61 chemical compositions including 16 terpenoids, 8 polyacetylenes, 6 aromatics, 5 flavonoids, 5 coumarins, 5 organic acids, 4 amino acids, 3 fatty acids, 3 aliphatics, 2 steroids, and 2 alkenes, a nucleoside and an aldehyde were identified. Simultaneously, the contents of three amino acids (L-tyrosine, L-phenylalanine, and L-tryptophan), three sesquiterpenoids (atractylenolide Ⅲ, atractylenolide Ⅱ, and atractylenolide Ⅰ), a flavonoid (rutin), an organic acid (ferulic acid), and a pentacyclic triterpenoid (oleanolic acid) were determined in seventeen AMR batches. Amino acids and triterpenoid were quantified for the first time in AMR. The UPLC-QTOF-MS method developed in this article was reliable, practical, and useful for qualitative and quantitative evaluation of AMR multi-components.

Open access
Acta Chromatographica
Authors:
Xiuhui Tian
,
Dianfeng Han
,
Yanmei Cui
,
Lihua Ren
,
Fang Jiang
,
Hui Huang
,
Xianghong Gong
,
Jinglin Xue
,
Jiawei Li
,
Huihui Liu
,
Yingjiang Xu
,
Xiaojun Luo
,
Xiaojing Liu
, and
Xiuzhen Zhang

Abstract

A sensitive and validated method for determining quinocetone and its main metabolites (3-methylquinoxaline-2-carboxylic acid and dedioxoquinenone) was established in aquatic products using ultra-high-performance liquid chromatography-tandem spectrometry (UHPLC-MS/MS). Samples were extracted with 2.0 mol L−1 hydrochloric acid, then purified on MAX columns. After extraction and purification, the supernatant was evaporated to dry nearly under a gentle stream of nitrogen at 40 °C. Formic acid-acetonitrile-water (0.1/30/70, v/v/v) was adjusted to 1.00 mL final volume. An aliquot (10 μL) was injected into the C18 column for separation with the mobile phase of acetonitrile and 0.5% formic acid in water at 0.25 mL min−1. Calibration curves were linear ranged from 10.00 ng mL−1 to 200.0 ng mL−1 for quinocetone and 3-methylquinoxaline-2-carboxylic acid, and 20.00 ng mL−1 to 400.0 ng mL−1 for dedioxoquinenone. Mean recoveries were 70%–89%, 73%–83% and 72%–84%, respectively. The limit of detection (LOD) was 1.00 μg kg−1, 1.00 μg kg−1 and 2.00 μg kg−1, and quantification (LOQ) were 2.00 μg kg−1, 2.00 μg kg−1 and 4.00 μg kg−1 for quinocetone, 3-methylquinoxaline-2-carboxylic acid, and dedioxoquinenone. Based on the method above, the analytes were determined in Apostichopus japonicus, three fishes (including Ctenopharyngodon idellus, Crucian carp and Oreochromis mossambicus), Penaeus vannamei, Penaeus chinensis, and Chlamys farreri. The method shows good sensitivity, linearity, precision, and accuracy. In short, the proposed method was reliable for the determination of quinocetone, 3-methylquinoxaline-2-carboxylic acid, and dedioxoquinenone in aquatic products.

Open access