JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
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2024
·
IF 3
Zhang Cong,Guo Yan,Xiao Libai,Gao Hongxu,Zhao Fengqi,Huang Jie,Lü Xingqiang,Ma Haixia
Three 4-(1 H -tetrazole-5-yl-amino)-1,2,4,5-tetrazine-1-one (TATzO) metal salts, K 2 (TATzO)(H 2 O) ( 1 ) and Mg(TATzO)(H 2 O) 6 ·2H 2 O ( 2 ) and Sr(TATzO)(H 2 O) 4 ( 3 ), were synthesized and characterized using Fourier transform infrared (FTIR), elemental analysis, single-crystal X-ray diffraction, and powder X-ray diffraction patterns. The crystal structure and hydrogen bonding interactions have been analyzed. It turns out that 1 and 3 crystallize into a three-dimensional topological network and have strong π – π stacking and hydrogen bonding interactions. Furthermore, the geometric optimization of 1 – 3 was performed using B3LYP-D3/def2svp in Gaussian 16 software package and then analyzed by reduced density gradient. The thermal behavior was conducted using differential scanning calorimetry and thermogravimetric (TG). The decomposition temperature of the three complexes exceeds 250 °C, much higher than that of TATzO (230 °C). The thermal decomposition products of 1 were further studied using thermogravimetric-Fourier transform infrared-mass spectrometry (TG/FTIR/MS). The impact sensitivity test indicated that making complexes can help decrease the sensitivity of the original energetic ligand. Graphical abstract
研究领域:
材料科学
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化学
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DOI
高影响因子
MICROCHEMICAL JOURNAL
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2021
·
IF 4.821
Yao Wei,Hua Jiang,Pengchi Deng
Sulfhydryl-containing amino acids had a variety of biological functions. Herein, a method was simply set up to determine Cys and GSH with β-CD AgNPs quantitatively. The chemical shifts of Cys and GSH both moved to higher field when β-CD AgNPs were added. The reason was that the sulfhydryl groups could bind to the surface of AgNPs. In addition, the competitive effect of Cys and GSH in mixed solutions was explored via the 1 H chemical shift deviation. Peaks at 3.05 ppm and 2.93 ppm were selected as characteristic signals. This method exhibited an excellent linearity in the range of Cys and GSH in 0.1–20 mM. The detection limits of Cys and GSH were 40 μM and 14 μM, respectively. This method was successfully used to quantitatively determine Cys and GSH in human serum and urine.
研究领域:
分析化学
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生物化学
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DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2019
·
IF 4.784
Kecheng Li,Andrew R. Green,Meredith M. Dinges,Cynthia K. Larive
Chitin oligosaccharides , composed of homogeneous β(1 → 4)-linked N -acetyl-D-glucosamine (GlcNAc) sequences, is a well-known elicitor of plant immune defense, and also occur as structural elements of chitosan and nodulation (Nod) factor. Detailed microstructure characterization is required for understanding the function mode of these bioactive molecules. Herein, experimental conditions for detection and elucidation of the 1 H NMR resonances of amide groups in chitin oligosaccharides are presented. The binary mixture of 70% H 2 O: 30% DMSO‑ d 6 was found to be the optimal solvent for amide proton measurements in homogeneous GlcNAc sequences, facilitating differentiation of the local chemical microenvironments of all four amide groups of the chitin tetrasaccharide . Experimental evidence that anomeric end-effect triggers amide proton resonance differentiation at the adjacent residue has potential to provide important insights into the solution structure of chitin and other amino sugars containing GlcNAc sequences.
研究领域:
生物化学
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植物免疫学
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分子生物学
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DOI
PubMed
高影响因子
FOOD CHEMISTRY
·
2019
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IF 5.399
Ting Shi,MengTing Zhu,XingYu Zhou,Xi Huo,You Long,XiangZhong Zeng,Yi Chen
Proton nuclear magnetic resonance ( 1 H NMR) combined with partial least squares (PLS) was developed for the rapid determination of squalene and sterols (brassicasterol, campesterol, stigmasterol and β-sitosterol) in 119 vegetable oils from 7 different species. The 1 H NMR spectra of these oil samples were correlated to the reference value determined by gas chromatography-mass spectrometry (GC–MS) method by PLS regression, using outlier removal, selection of input X-variables and data pretreatments. Auto-scaling (UV) was chosen as the best pre-processing for the PLS models of stigmasterol, β-sitosterol, and squalene. Pareto variance (Par) was more suitable for the PLS model of brassicasterol. The model for squalene was further improved by a reduced number of variables with variable importance for the projection (VIP) scores technique. The study demonstrated the potential application of NMR coupled with PLS as a rapid and nondestructive technique for the routine analysis of squalene and sterols in vegetable oils.
研究领域:
食品科学
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分析化学
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DOI
PubMed
高影响因子
EUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY
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2015
·Vol. 117
·期 7
·918-925
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IF 1.812
Ziliang Song,Yong Wang,Guoqiang Li,Wei Tan,Shengwen Yao
A new approach for determination of glycidyl fatty acid esters (GDEs) based on 1 H nuclear magnetic resonance ( 1 H NMR) spectroscopy was developed. The 1 H NMR spectra of the GDE standards were prepared and characterized. The quantification formula was then deduced from the characteristic signals of two epoxy methylene (CH 2 ) protons at chemical shifts 2.56 and 2.76 ppm. Tests on repeatability, reproducibility, and recovery were conducted and proved the reliability of the quantification method. This method was extended to GDEs mixed with oil matrices composed of different acylglycerols (GREs). The weighted average factor f w is introduced to calculate the fatty acid composition based on the stoichiometric proportion of the lipid component and its esterification degree. With the fatty acid composition determined, the molar percentage obtained from 1 H NMR can be converted to the weight percentage. This method is an analytical model for the determination of GDEs, with advantages such as easy operation and high accuracy. Practical applications: Heat treatment of edible oils in the refinery process can generate GDEs, a group of contaminants having potential risks to liberate a carcinogenic compound called glycidol during digestion of oil in the human body. It has become an important issue for the oil industry to develop an effective method for the determination of GDEs. The proposed 1 H NMR spectroscopic method is able to characterize and quantify GDEs in an accurate, rapid, and noninvasive way. With these advantages, the analytical results also provide quantitative criteria for subsequent concentration and mitigation of GDEs in refined edible oils. A novel 1 H NMR spectroscopic method was developed to determine glycidyl fatty acid esters (GDEs), a processing contaminant in refined edible oil.
研究领域:
食品科学
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分析化学
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DOI
高影响因子
RSC Advances
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2022
·Vol. 12
·期 15
·9342-9350
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IF 4.036
Yuyi Zhang,Wei Zhang,Yajie Bian,Yiting Liu,Xiaolei Zhang,Mengdi Chen,Bingwen Hu,Qingyuan Jin
Zeolitic imidazolate framework-8 (ZIF-8) is one of the most promising metal–organic frameworks because of its excellent high porosity, stability and geometrically well-defined structure. However, the application of ZIF-8 in the field of fluorescent molecular sensing has not been intensively explored. Our work demonstrates the versatility of ZIF-8 as a carrier material, which can be used for small molecule [2-(2-hydroxyphenyl)-1H-benzimidazole (HPBI)] capture and fluorescence enhancement. ZIF-8 displays luminescent behavior changes when combined with HPBI, as the emission peaks of ZIF-8 and HPBI are located in the same range for resonance enhancement of fluorescence. The results of the experiment indicate that the fluorescence enhancement effect will change in the presence of different concentrations of HPBI. We propose that the pore structure of ZIF-8 could provide an opportunity for the adsorption of HPBI molecules, and eventually the adsorption would saturate. The high porosity of ZIF-8 provides the path to HPBI aggregation or entrance into the ZIF-8 internal structure. Our results suggest that ZIF-8 may offer great promise for molecular fluorescence sensing.
研究领域:
材料科学
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化学
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DOI
PubMed
高影响因子
MAGNETIC RESONANCE IN MEDICINE
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2022
·Vol. 89
·期 5
·1728-1740
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IF 3.737
Jia-Xiang Xin,Da-Xiu Wei,Yan Ren,Jun-Long Wang,Guang Yang,Huojun Zhang,Jianqi Li,Caixia Fu,Ye-Feng Yao
Purpose The signals of glutamate (Glu) and glutamine (Gln) are often significantly overlapped in routine 1 H-MR spectra of human brain in vivo. Selectively probing the signals of Glu and Gln in vivo is very important for the study of the metabolisms in which Glu and Gln are involved. Methods The Glu−/Gln- targeted pulse sequences are developed to selectively probe the signals of Glu and Gln. The core part of the Glu−/Gln- targeted pulse sequences lies on the preparation of the nuclear spin singlet orders (SSOs) of the five-spin systems of Glu and Gln. The optimal control method is used to prepare the SSOs of Glu and Gln with high efficiency. Results The Glu−/Gln- targeted pulse sequences have been applied on phantoms to selectively probe the signals of Glu and Gln. Moreover, in the in vivo experiments, the signals of Glu and Gln in human brains of healthy subjects have been successfully probed separately. Conclusion The developed Glu−/Gln- targeted pulse sequences can be used to distinguish the 1 H-MR signals of Glu and Gln in human brains in vivo. The optimal control method provides an effective way to prepare the SSO of a specific spin system with high efficiency and in turn selectively probe the signals of a targeted molecule.
研究领域:
医学影像学
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代谢组学
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DOI
PubMed
高影响因子
Membranes
·
2023
·Vol. 13
·期 1
·61
·
IF 4.2
Olga Yu. Selyutina,Anna V. Mastova,Nikolay E. Polyakov
Anthracycline antibiotics, e.g., doxorubicin, daunomycin, and other anthraquinones, are an important family of antitumor agents widely used in chemotherapy, which is currently the principal method for treating many malignancies. Thus, development of improved antitumor drugs with enhanced efficacy remains a high priority. Interaction of anthraquinone-based anticancer drugs with cell membranes attracts significant attention due to its importance in the eventual overcoming of multidrug resistance (MDR). The use of drugs able to accumulate in the cell membrane is one of the possible ways of overcoming MDR. In the present work, the aspects of interaction of anthraquinone 2-phenyl-4-(butylamino)naphtho[2,3-h]quinoline-7,12-dione) (Q1) with a model membrane were studied by means of NMR and molecular dynamics simulations. A fundamental shortcoming of anthracycline antibiotics is their high cardiotoxicity caused by reactive oxygen species (ROS). The important feature of Q1 is its ability to chelate transition metal ions responsible for ROS generation in vivo. In the present study, we have shown that Q1 and its chelating complexes penetrated into the lipid membrane and were located in the hydrophobic part of the bilayer near the bilayer surface. The chelate complex formation of Q1 with metal ions increased its penetration ability. In addition, it was found that the interaction of Q1 with lipid molecules could influence lipid mobility in the bilayer. The obtained results have an impact on the understanding of molecular mechanisms of Q1 biological activity.Keywords:anthraquinones;NMR;molecular dynamics;lipid membranes
研究领域:
药理学
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生物物理学
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DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2024
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IF 8.1
Feng-Ying Wu,Yan Cheng,Xin-Yue Yuan,Qi-Lei Sun,Fu-Min Xue
The study investigated the extraction of alkaloids and glycosides from the Camptotheca acuminata Decne using deep eutectic solvent (DES). 18 types of deep eutectic solvents (DESs) were prepared, and it was found that the extraction performance of choline chloride (ChCl)-formic acid (FA) was optimal, surpassing traditional solvents such as methanol/70 % methanol. In comparison to methanol, the extracted amount of compounds by DES was 2–3 times higher. The extraction processes involving the molar ratio of ChCl-FA, pH, DES/H 2 O mass ratio, solid/liquid ratio, as well as ultrasonic power were optimized. A mathematical model for solid/liquid extraction kinetics from Camptotheca acuminata Decne was developed. The extraction mechanism was investigated using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), and 1 H nuclear magnetic resonance( 1 H NMR). The results revealed that the DES caused dissociation in Camptotheca acuminata Decne and formed hydrogen bonds with Camptothecin (CPT). Meanwhile, density functional theory (DFT) calculations verified that FA-based exhibited the highest extracted amount for CPT. In addition, this study investigated the recovery rate of DES, and the results showed that after 10 cycles, the DES system remained effective for the extraction of alkaloids and glycosides.
研究领域:
药学
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分析化学
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植物化学
·
提取技术
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DOI
高影响因子
ACS Applied Polymer Materials
·
2025
·
IF 4.7
Md Alim Uddin,Yihua Shen,Li Wang,Haojie Yu,Huanan Wang,Xunchun Yuan,Abdul Basit,Muhammad Owais Malik,Khan Manqoosh Awan,Lichang Xu,Xiwang Yuan,Qiang Li
Because it is noninvasive and radiation-free, magnetic resonance imaging (MRI) is a commonly used imaging method that is very helpful for the early detection and monitoring of malignant growths. The development of alternative imaging probes is essential to reducing the toxicity of contrast agents (CAs) based on metals, such as gadolinium (Gd), which are used in clinical settings. Our goal is to create innovative MRI contrast agents that do not require metallic components and have great stability and relaxivity while still exhibiting excellent efficacy. In this work, the esterification reaction and ring-opening polymerization methods used to successfully synthesize pectin-nitroxide nanoconjugates are demonstrated, and their effective use as a CA for MRI is established. For each radical, the nanoconjugates have a favorable longitudinal water 1H relaxivity of 0.23 and 0.41 mM–1 s–1 for the pectin-TEMPO (PT) and pectin-PGTEMPO (PPGT). The PPGT exhibits notable characteristics like nontoxicity in vivo and resistance to quenching. For longer than 3 h, the PPGT in Wistar female rats shows increased MRI contrast. Comparable contrast enhancement is achieved with PPGT at 3.85 times lower (0.026 mmol/kg) than the standard dose (0.1 mmol/kg). Consequently, the PPGT shows promise as a workable metal-free MRI CA.
研究领域:
医学影像学
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生物材料学
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DOI
高影响因子
TALANTA
·
2015
·
IF 3.545
Yakun Lian,Hua Jiang,Jinzhou Feng,Xiaoyan Wang,Xiandeng Hou,Pengchi Deng
ATP , ADP and AMP are energy substances with vital biological significance. Based on the structural differences, a simple, rapid and comprehensive method has been established by 1 H and 31 P Nuclear Magnetic Resonance ( 1 H-NMR and 31 P-NMR) spectroscopies. Sodium 3-(trimethylsilyl) propionate-2,2,3,3-d 4 (TMSP) and anhydrous disodium hydrogen phosphate (Na 2 HPO 4 ) were selected as internal standards for 1 H-NMR and 31 P-NMR, respectively. Those three compounds and corresponding internal standards can be easily distinguished both by 1 H-NMR and 31 P-NMR. In addition, they all have perfect linearity in a certain range: 0.1–100 mM for 1 H-NMR and 1–75 mM for 31 P-NMR. To validate the precision of this method, mixed samples of different concentrations were measured. Recovery experiments were conducted in serum (91–113% by 1 H-NMR and 89–113% by 31 P-NMR).
研究领域:
生物化学
·
医学检测
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DOI
PubMed
高影响因子
CHEMICAL PAPERS
·
2014
·Vol. 69
·期 2
·325-338
·
IF 1.193
Jian Zhang,Tian-Qi Zhao,Yao Chen,Xiao-Dong Chen,Hai-Kun Chang,Yu-Min Zhang,Shu-Cheng Hua
A solvent-free microwave-assisted method for the synthesis of 2-substituted-4,5-di(2-furyl)-1H-imidazoles was developed. Imidazoles with moderate to good yields were produced by condensation of furil with aldehydes over acidic alumina impregnated with ammonium acetate, and they were characterized by FT-IR, HRMS, 1 H NMR and 13 C NMR spectroscopy. Crystal structure of 2,4,5- tri-2-furyl-1H-imidazole (I ) in the orthorhombic space group Pbca was reported, which showed more coplanarity than the reported crystal structure of I in the monoclinic space group Cc. Moreover, their luminescent properties were investigated. It was found that the organic small molecule compounds synthesized possess higher fluorescence quantum efficiency (up to 0.508) in a 0.1 M H 2 SO 4 aqueous solution dissolved in 0.5 mL of CH 3 OH; along with higher stability; also the emission of some compounds synthesized in the solution was sensitive to the polarity of the solvents.
研究领域:
有机化学
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材料科学
·
光化学
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DOI
高影响因子
危险品化学品经营许可证（带存储）