CRYSTENGCOMM
·
2019
·Vol. 22
·期 3
·448-457
·
IF 3.382
Hao Liu,Xing Yang,Shanyu Wu,Mingtao Zhang,Sean Parkin,Shuang Cao,Tonglei Li,Faquan Yu,Sihui Long
Flunixin [2-(3-trifluoromethyl-2-methyl-phenylamino)-nicotinic acid, FLX], a potent nonsteroidal anti-inflammatory drug widely used in veterinary medicine, was found to exist in at least two crystal forms (I and II), in contrast to clonixin [2-(3-chloro-2-methyl-phenylamino)-nicotinic acid, CLX], which exists in four solvent-free forms and multiple solvates. Form I was harvested from a variety of solvents and characterized by single-crystal X-ray diffraction, PXRD, FT-IR, and Raman spectroscopy. Its crystal structure is sustained on the strong acid–pyridine hydrogen bond. Form II was generated by thermal treatment of form I. Other aspects of this polymorphic system were investigated both experimentally and theoretically. Quantum chemistry calculations were performed to shed light on the lack of polymorphism from solution-phase crystallization. Conformational scan of the dihedral angle C2–N7–C8–C9 (τ) revealed two stable conformations, one with τ near 170°, and the other near 70°, corresponding to the molecule in the crystal. Hirshfeld analysis accounted for the major intermolecular interactions contributing to the overall stability of the crystal.
研究领域:
药学
·
晶体学
·
兽医学
✓ 已验证
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2022
·
IF 9.136
Chaoqun Tan,Wangqi Yu,Hong Mei,Kaiyang Chen,Tianhui Xu,Huiming Xiang,Yiming Feng,Lin Deng
In this study, Fe(III) catalyzed calcium peroxide (CaO 2 , CP) Fenton-like process assisted by crystal boron (C-boron) was applied for in situ chemical oxidation. Flunixin meglumine (FMME), aspirin (ASA), nitrobenzene (NB) and benzoic acid (BA) were selected as target contaminants. Pollutants decomposition by the CP/Fe(III) and C-boron/CP/Fe(III) systems was proposed in terms of diverse parameters, including C-boron dosage, pH, and temperature, with regard to the pseudo-first-order kinetic model (R 2 > 0.95). About 26.8% of 20 μM FMME was removed by 0.5 mM CP and 0.5 mM Fe(III) after 20 min at pH 4.0, whereas 90.4% of FMME was decomposed in the C-boron/CP/Fe(III) system with 100 mg/L C-boron. The removal rates of the other three pollutants were also improved to varying degrees. The k obs of the C-boron/CP/Fe(III) system for these four pollutants degradation at pH 4.0 was approximately 4.1 ∼ 5.3 times higher compared to the CP/Fe(III) system. Electron paramagnetic resonance and quenching experiments indicated that OH, O 2 − and 1 O 2 were present in both systems and contribution of OH was 71.3% at initial pH 4.0 in C-boron/CP/Fe(III) system, suggesting that it was the main reactive oxygen species for the contaminants elimination. Furthermore, experiments on the characterization of C-boron showed great reactivity and stability. This work manifested the promotion mechanism of pollutant degradation in the C-boron/CP/Fe(III) system.
研究领域:
环境科学
·
化学工程
·
水处理
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CHROMATOGRAPHY B-ANALYTICAL TECHNOLOGIES IN THE BIOMEDICAL AND LIFE SCIENCES
·
2023
·
IF 3
Zhixuan Sun,Miao Li,Sixuan Qian,Yani Gu,Jingjie Huang,Jiancheng Li
The ultra-performance liquid chromatography with tandem mass spectrometry (UPLC-MS/MS) detection method was developed for the residues of 10 NSAIDs (salicylic acid, acetylsalicylic acid, acetaminophen, diclofenac, tolfenamic acid, antipyrine, flunixin meglumine, aminophenazone, meloxicam, metamizole sodium) in swine muscle, liver, kidney, and fat. Swine tissue samples were extracted by phosphorylated acetonitrile with the addition of an appropriate amount of internal standard working solution, defatted with acetonitrile-saturated n -hexane, and purified by Hydrophile-Lipophile Balance (HLB) solid-phase extraction column, then separated by UPLC BEH shield RP 18 column with 0.1% formic acid in water/0.1% formic acid in acetonitrile with gradient elution, which was detected in the multiple reaction monitoring (MRM) modes. The correlation coefficient of the standard curve equation is greater than 0.99, and the coefficient of variation within and between batches is less than 14.4%. We evaluated the analytical method using two green assessment tools. The method established in this study met the requirements of NSAID residue analysis and provides analytical tools for determining and confirming NSAIDs in swine tissue samples. This is the first report on the simultaneous determination of 10 NSAIDs in four swine tissues by the UPLC-MS/MS method and accurate quantification using deuterated internal standards.
研究领域:
分析化学
·
兽医学
·
药理学
·
食品安全
✓ 已验证
产品关联
DOI
PubMed
高影响因子