Analytical Methods
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2020
·Vol. 12
·期 17
·2221-2227
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IF 2.596
Junjie Du,Qiwei Zhang,Jianjun Li,Qi Zheng
Sialic acid (Sia) is widespread in vertebrates and humans as well as in some microbes and invertebrates. It is well known that O-acetylation is a common modification for Sia. Also, highly O-acetylated Sias have been reported in humans, bovines, and fish. Derivatization based on 1,2-diamino-4,5-methylenedioxybenzene (DMB) coupled with LC-fluorescence detection or LC-MS analysis has been the routine analytical strategy for O-acetylation profiling of Sias. Unfortunately, DMB offers poor chromatographic resolution for some O-acetylated species. Herein, we report another derivatization reagent, 4,5-dimethylbenzene-1,2-diamine (DMBA), for the LC-MS analysis of Sia isomers. The DMBA method was first evaluated using Sia reference standard, horse serum and carp blood. The results demonstrate that DMBA provides superior chromatographic separation efficiency and comparable MS/MS spectra to DMB. The proposed method was then applied to the analysis of relative abundance of each Sia species in fish tissues, including liver, intestine, muscle and brain. It was found that the relative amounts of Sia species were significantly different among the four tissues. Thus, DMBA derivatization-based LC-MS methods have great potential in investigating the O-acetylation level of Sias in various samples, such as human food and bio-pharmaceutical products.
研究领域:
分析化学
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生物化学
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药学
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产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2016
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IF 5.31
Lidong Wang,Shanlong An,Qiangwei Li,Songhua Yu,Siyu Wu
Coal-fired flue gas is a major source of greenhouse gas CO 2 . Phase-change absorbents can be used to reduce energy consumption associated with regeneration during CO 2 capture. In this study, N,N-dimethylbutylamine (DMBA) and N,N-dimethylbutylamine (DEEA) were mixed to develop phase-change absorbents, and the reaction kinetics of CO 2 absorption in the absorbents were examined. A bubbling device was used to prepare phase-change absorbents with different CO 2 loading levels. The physico-chemical parameters of the absorbents under different conditions were specified, and the changes in the CO 2 loading of the upper and lower layers of the absorption solutions after a liquid–liquid separation were analyzed. A wetted-wall column was subsequently used to investigate the effects of temperature, CO 2 loading, gas flow rate, and DMBA/DEEA composition ratio on CO 2 absorption rate. This study determined that the flow velocity, reaction temperature, and CO 2 loading affected the CO 2 absorption rates to a certain extent. In addition, comparing the reactive properties of the 4M DMBA + 2M DEEA and 2M DMBA + 4M DEEA absorbents under the same experimental conditions revealed that the 4M DMBA + 2M DEEA absorbent exhibited higher absorption rate and reaction stability. A kinetics model also indicated that the CO 2 absorption of the phase-change absorbents used in this study was mainly affected by the liquid film diffusion process. This study contributes theoretically to the development of CO 2 absorption technologies.
研究领域:
化学工程
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环境科学
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能源技术
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DOI
高影响因子
INDUSTRIAL CROPS AND PRODUCTS
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2018
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IF 3.849
Haiyan Liang,Shanwen Wang,Heng He,Mengqi Wang,Lingxiao Liu,Jingyi Lu,Yi Zhang,Chaoqun Zhang
In this study, dimethylol propionic acid (DMPA) and dimethylol butanoic acid (DMBA) were employed to synthesize the castor oil-based waterborne polyurethane dispersions (PUDs). The effects of these two emulsifier and their contents on the properties of the PUDs as well as their films were investigated systematically. The results show that as the emulsifiers contents increase, the particle size and zeta potential of the PUDs decrease while the tensile strength of the resulting PU films increase but thermal stability, water and chemical resistance decrease. The PUDs from DMBA exhibit smaller particle size than those from DMPA and the films from the former show higher tensile strength, higher elongation at break but lower thermal stability, lower water resistance. This work provides a new way to synthesize environmental friendly bio-based waterborne polyurethanes whose properties can be tuned according to their application, such as coating, ink, leather, styling products and so on.
研究领域:
材料科学
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化学工程
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产品关联
DOI
高影响因子
Journal of Functional Foods
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2020
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IF 3.701
Jia-hua Kuang,Yan-yan Huang,Jin-shuang Hu,Jia-jia Yu,Qin-yu Zhou,Dong-mei Liu
Accumulating evidences have reported that polysaccharide could alleviate colitis through the maintenance of intestinal homeostasis. In this study, an exopolysaccharide (EPS-K4) from Bacillus amyloliquefaciens was obtained via anionic-exchange chromatography which was with an average molecular weight of 10,067 Da and consisted of mannose, rhamnose, glucuronic acid, and glucose with a molar ratio of 40.09:23.65:11.42:17.68. Furthermore, administration of EPS-K4 relieved symptoms in colitis mice via gut microbiota modulation. The levels of pathogenic bacteria, such as Enterococcus and Escherichia - Shigella , were significantly suppressed. In contrast, the levels of Lactobacillus and intestinal microbiota diversity were increased. EPS-K4 could stimulate mucin secretion to maintain the integrity of the gut barrier and decrease the levels of virulent substances (endotoxin, diamine oxidase, and D-lactic acid) in serum. The pro-inflammatory cytokines (TNF-α) in serum were reduced, conversely, anti-inflammatory cytokines (IL-10) were increased. These findings indicated the possibility of EPS-K4 as a chemotherapy candidate for the prevention of colitis.
研究领域:
微生物学
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免疫学
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胃肠病学
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DOI
高影响因子
MICROSCOPY RESEARCH AND TECHNIQUE
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2025
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IF 2.1
Samaira Mumtaz,Shaukat Ali,Asim Pervaiz,Farooq Ahmad,Asma Abdul Latif,Mah Noor Khan,Muhammad Khalil Ahmad Khan,Muhammad Adeeb Khan,Ali Hassan,Rizwan Ullah,Tafail Akbar Mughal,Saiqa Andleeb,Hafiz Muhammad Tahir
Nanotechnology is an emerging field in the therapeutic domain of cancer research. The development of novel anticancer agents in combination with nanotechnology is a highly promising area as it could offer safer and more effective delivery methods for better overall outcomes. Considering this, a naturally occurring silkworm protein (sericin) was combined with nanoparticle formulations to explore the subsequent anticancer effects in breast cancer. In this study, a breast cancer animal mice model was developed by using 7, 12-dimethylbenzneanthracene (DMBA) (a carcinogenic compound) followed by evaluation of the antitumor effects of a natural protein (sericin) and its nanoparticle conjugates. For this purpose, the mice were treated with two different concentrations of individual sericin protein together with conjugated silver nanoparticles (100–200 mg/kg, b.w.). Mice were dissected after 60 days of the treatment, and biochemical results showed that sericin and its conjugated nanoparticles had significant effects against the DMBA-induced carcinogenic group in comparison with the untreated control group. Particularly, sericin-conjugated NPs induced more prominent effects in the animal model. The histopathological analysis of the spleen and mammary tissues showed cytotoxic effects in the DMBA group, and sericin-conjugated NPs were highly effective and minimized the cytotoxic effects of DMBA. Consequently, sericin-conjugated nanoparticles induced more efficient anti–breast tumor effects in animal mice models and have promising future clinical applications in overcoming drug resistance.
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DOI
PubMed
高影响因子
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