AAPS PHARMSCITECH
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2020
·Vol. 21
·期 8
·1-11
·
IF 2.401
Su Yanping,Lu Wenxiang,Fu Xiaoling,Xu Ying,Ye Lixiang,Yang Jian,Huang Huihui,Yu Changxi
The aim of this study was to develop a suitable drug-in-adhesive patch for transdermal delivery of koumine. Acrylic polymer Duro-Tak® 87-4287, which contains hydroxyl groups, may significantly enhance the skin permeation of koumine from transdermal patches containing 0.93–3.72% koumine. Among permeation enhancers, 10% azone showed the greatest potential and increased the flux of koumine to 1.48-fold that of the control. Therefore, an optimized patch formulation containing 3.72% koumine and 10% azone in Duro-Tak® 87-4287 that offers good physical properties was selected for an in vivo pharmacokinetic study using rats. The maximal plasma drug concentration ( C max ) of koumine after transdermal administration (4 mg/patch) was 25.80 ± 1.51 ng/mL, which was in the range of those after oral administration (3 mg/kg and 15 mg/kg). The time to the maximal concentration ( T max ) and the half-life ( t 1/2 ) of the drug with transdermal administration were 3.96 ± 0.46 h and 21.10 ± 1.36 h, respectively, which were longer than those with oral administration. Furthermore, the area under the concentration-time curve (AUC 0–72 h ) of 898.20 ± 45.57 ng·h/mL for the transdermal patch was much higher than that for oral administration (15 mg/kg). In conclusion, the drug-in-adhesive patch containing koumine provides a steady plasma koumine level and sustained release in vivo and can be an effective means of transdermal delivery for koumine.
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Nature Communications
·
2020
·Vol. 11
·期 1
·1-11
·
IF 12.121
Hao Shaoyun,Liu Min,Pan Junjie,Liu Xiangnan,Tan Xiaoli,Xu Nan,He Yi,Lei Lecheng,Zhang Xingwang
Designing highly durable and active electrocatalysts applied in polymer electrolyte membrane (PEM) electrolyzer for the oxygen evolution reaction remains a grand challenge due to the high dissolution of catalysts in acidic electrolyte. Hindering formation of oxygen vacancies by tuning the electronic structure of catalysts to improve the durability and activity in acidic electrolyte was theoretically effective but rarely reported. Herein we demonstrated rationally tuning electronic structure of RuO 2 with introducing W and Er, which significantly increased oxygen vacancy formation energy. The representative W 0.2 Er 0.1 Ru 0.7 O 2-δ required a super-low overpotential of 168 mV (10 mA cm − 2 ) accompanied with a record stability of 500 h in acidic electrolyte. More remarkably, it could operate steadily for 120 h (100 mA cm − 2 ) in PEM device. Density functional theory calculations revealed co-doping of W and Er tuned electronic structure of RuO 2 by charge redistribution, which significantly prohibited formation of soluble Ru x>4 and lowered adsorption energies for oxygen intermediates.
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JOURNAL OF NANOPARTICLE RESEARCH
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2020
·Vol. 22
·期 11
·1-13
·
IF 2.132
Wang Jing,Ma Dong-Mei,Feng Ying-Xin,Xian Yu,Qian Dong-Jin
Artificial pigments of metalloporphyrin derivatives are effective catalysts for the degradation of toxic organic dyes, phenols, and other pollutants. We reported here an interfacial layer-by-layer (LBL) assembly of multiporphyrin arrays on the surface of multi-walled carbon nanotubes (MWNTs) with the use of Na 2 PdCl 4 as a connector and manganese (III) meso-tetra(4-pyridyl)porphine acetate (MnTPyP) as a linker, respectively. Thermogravimetric analysis revealed that the relative content of organic species in the MWNT@(Pd-MnTPyP) n nanocomposites increased gradually with more layers of Pd-MnTPyP assembled. The Soret absorption band of MnTPyP displayed approximately 20-nm redshift in the nanocomposites due to the increase of porphyrin-porphyrin interaction within the Pd-MnTPyP ultrathin films. The specific surface area was about 513.1 and 47.7 m 2 /g for the original MWNTs and MWNT@(Pd-MnTPyP) 3 nanocomposites, respectively. Finally, the nanocomposites were used as heterogeneous catalysts for catalytic degradation of toxic 1-naphthol, 1,5-dihydroxynaphthalene, 5-amino-1-naphthol, and 1-naphthol-5-sulphonic acid in phosphate buffer, using H 2 O 2 as the oxidant. It was revealed that, when the nanocomposites were used, the catalytic efficiency could increase by 2 to 3 orders of magnitude. Higher catalytic efficiency was observed for the naphthols bearing the electron-donating group of hydroxyl or amino than those bearing an electron-withdrawing group of sulfonic acid.
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JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY
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2021
·Vol. 327
·期 3
·1251-1258
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IF 1.371
Fu Xuan,Zhang Fang,Wu Qiang,Li Yang,Huang Qing-Gang,Yan Ze-Yi
In this study, extraction and separation of thorium(IV) and a few representative rare earths in HNO 3 media was evaluated using trioctylmethylammonium nitrate ([A336][NO 3 ]) ionic liquid. An unexpected novel extraction mechanism was identified based on the studies in the slope analysis and ESI–MS spectrum. The trimer of [A336][NO 3 ] was confirmed to dominate the extraction reaction by ESI–MS spectrum before and after the extraction. The extraction efficiency of La(III), Eu(III) and Lu(III) by [A336][NO 3 ] are much lower than Th(IV) in acid medium, which means that it is possible to separate thorium from rare earths or the rare earth ores by using [A336][NO 3 ].
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Marine Life Science & Technology
·
2020
·Vol. 3
·期 1
·85-93
·
IF 0
Chen Rui,Huang Wen-Can,Wang Wei,Mao Xiangzhao
Chitin nanofibers have recently received increased attention and are considered to be a promising material for a wide range of applications because of their excellent characteristics. In this study, 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)-oxidized chitin nanofibers (CNFs) with various oxidation times were prepared and characterized. CNFs with different oxidation times were then utilized for enzyme immobilization, using chymotrypsin as a model enzyme. The effects of oxidation time on enzyme immobilization were explored. Results showed characteristics of chitin nanofibers can be controlled by adjusting oxidation time. CNFs treated with TEMPO for 360 min showed the lowest crystallinity (79.13 ± 1.43%), the shortest length (241.70 ± 74.61 nm), the largest width (12.67 ± 3.43 nm), and the highest transmittance (73.01% at 800 nm). The activity of immobilized enzymes and enzyme loading showed good correlation to the carboxylate content of CNFs. The enzyme efficiency based on CNFs and the content of carboxylate groups peaked at the oxidization time of 60 min. When the additional amount of chymotrypsins (CTs) was 500 or 2000 mg/g carrier, the highest loading amount of CTs was 307.17 ± 4.08 or 726.82 ± 12.05 mg/g carrier, respectively.
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MICROCHIMICA ACTA
·
2020
·Vol. 187
·期 11
·1-13
·
IF 6.232
Wang Zelan,Meng Zhe,Zhao Mengxin,Men Xiuqin,Yang Jinhui,Li Jiguang
A novel magnetic hollow bimetallic zinc/cobalt-based zeolitic imidazolate framework (MHB-Zn/Co-ZIF-8) was prepared via a microwave-assisted chemical etching in methanol. The structure, morphology, and specific surface area were characterized by X-ray diffraction and FTIR spectroscopy, scanning and transmission electron microscopy, and N 2 adsorption. The hollow nanostructures with high internal specific surface area, abundant active sites, and reduced aggregation of nanoparticles endow the hollow zeolitic imidazolate framework (ZIF) nanoparticle with high chemical stability, desirable durability, and excellent adsorption abilities. The MHB-Zn/Co-ZIF-8 nanoparticle was used as an effective sorbent for magnetic solid-phase extraction (MSPE) of trace aflatoxins B 1 , B 2 , G 1 , and G 2 from fruit juice and fruit samples. The main parameters affecting the efficiency of MSPE procedures were investigated and optimized. The results show that, under optimized conditions, enrichment factors ranging from 67- to 355-fold are obtained for the target analytes. The method is linear in the range 1.0 to 100.0 ng mL −1 with correlation coefficients ( R 2 ) from 0.9960 to 0.9992. The limits of detection of four aflatoxins are in the range 0.18 to 1.50 ng mL −1 and the average recoveries range from 75.1 to 102.4%, with relative standard deviations (RSDs) less than 13.6%. This work presents the excellent extraction performance of aflatoxins B 1 , B 2 , G 1 , and G 2 on MHB-Zn/Co-ZIF-8. In addition, the applicability of the MSPE coupling with ultrahigh-performance liquid chromatography-ion trap tandem mass spectrometry (UHPLC-IT-MS n ) for trace analysis in complex matrices is shown.
Schematic presentation of magnetic hollow bimetallic zinc/cobalt zeolitic imidazolate framework as sorbent for efficiently enriching aflatoxins B 1 , B 2 , G 1 , and G 2 from fruit juice samples prior to ultrahigh-performance liquid chromatography-ion trap tandem mass spectrometry (UHPLC-IT-MS n ) determination.
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ANALYTICAL AND BIOANALYTICAL CHEMISTRY
·
2020
·Vol. 413
·期 1
·215-223
·
IF 3.637
Li Na,Zhao Tengwen,Du Li,Zhang Ziyang,Nian Qixun,Wang Manman
A graphitic carbon nitride (g-C 3 N 4 /Fe 3 O 4 )–based magnetic solid-phase extraction (MSPE) approach was established for fast and simple analysis of estrogens in milk powders. The composites were characterized by X-ray diffractometer, scanning electron microscope, and Brunauer-Emmett-Teller surface area and pore size distribution analyzer. Compared with the bulk g-C 3 N 4 , g-C 3 N 4 /Fe 3 O 4 gave a narrower distribution of mesopores and provided an enhanced surface area from 77.1 to 113.7 m 2 /g. Polar analytes of estrogens were selected as model compounds and the extraction of four estrogens was achieved in n-hexane using 15 mg of adsorbent within only 2 min. Possible extraction mechanism of g-C 3 N 4 /Fe 3 O 4 for these estrogens was explored in terms of the polarity of the analytes and the adsorption performance of the adsorbent. The hydrophobicity and the hydrogen-bond interaction between the estrogens and g-C 3 N 4 were responsible for the efficient adsorption. Combined with HPLC, MSPE with the prepared adsorbent gave the enhancement factors of 20 to 24 and the linear ranges of 2–200 μg/kg for 17 β -estradiol and 17 α -ethinylestradiol, 1.5–150 μg/kg for estrone, and 3–300 μg/kg for hexestrol. The detection limits and quantification limits for the estrogens in milk powders were 0.5–0.9 μg/kg and 1.5–3.0 μg/kg, respectively. The recoveries varied from 75.1 to 97.2%, with the intra-day and inter-day precisions ≤ 14.2%. Furthermore, the enrichment of the analytes and the clean-up of fat and protein interferences were achieved simultaneously with one-step g-C 3 N 4 -based MSPE. The present method was convenient, fast, and sensitive, and therefore could be successfully applied for the determination of estrogens in milk powders.
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MICROCHIMICA ACTA
·
2021
·Vol. 188
·期 3
·1-8
·
IF 5.833
Zhang Bing,Hu Xing,Jia Yejing,Li Jing,Zhao Zhihuan
A photothermal immunoassay using a thermometer as readout based on polyaniline@Au organic-inorganic nanohybrids was built. Temperature output is acquired due to the photothermal effect of the photothermal nanomaterial. Polyaniline@Au organic-inorganic nanohybrids were synthesized by interfacial reactions with high photothermal conversion efficiency. A sandwich structure of the immunocomplex was prepared on a microplate for determination of carcinoembryonic antigen (CEA) by polyaniline@Au organic-inorganic nanohybrids as nanolabel. The released heat based on light-to-heat conversion from the photothermal nanolabel under NIR irradiation is detectable using the thermometer. The increased temperature is directly proportional to CEA concentration. The linear range of the photothermal immunoassay is 0.20 to 25 ng mL −1 with determination limit of 0.17 ng mL −1 . Graphical abstract
Polyaniline@Au organic-inorganic nanohybrids with high photothermal conversion efficiency was synthesized as labels to construct photothermal immunosensor. The sandwich-type immunoassay was built on 96 hole plate based on specific binding of antigen and antibody. Carcinoembryonic antigen in sample was detected quantitatively by thermometer readout.
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ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2021
·Vol. 28
·期 16
·20002-20011
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IF 4.223
Zhu Difeng,Ping Li,Qian Renyun,Chen Chao,Hong Yawen,Tong Zhenxuan,Yang Xiaochun
Forchlorfenuron (CPPU) is often applied during the cultivation of kiwifruit to produce larger fruit. To address degradation patterns of CPPU during simulated cold chain logistics and simulated shelf life of the fruit after harvest, appropriate storage methods and safe consumption behavior can be investigated. In this study, an ultra-high-performance liquid chromatography-tandem mass spectrometry method was adopted to detect CPPU residues under different conditions. CPPU in kiwifruit stored at 6 °C had a half-life of 40.8–77.0 days. However, when kiwifruit was stored at 0 °C under simulated cold chain storage conditions, the half-life of CPPU was 63.0–115.5 days, implying that lower storage temperatures can reduce the degradation rate of CPPU. The residues of CPPU in kiwifruit pulp declined with time, and the reduction followed the first-order kinetics equation. More CPPU residues were present in the pulp of postharvest kiwifruit treated with exogenous ethylene than in the pulp of untreated kiwifruit. Thus, using exogenous ethylene for artificial ripening after harvest is not recommended. We determined that the appropriate cold chain storage temperature is 6 °C. It is recommended that the public select kiwifruit stored for at least 2 weeks. The estimated chronic and acute dietary risk quotients of CPPU are ≤ 0.79% and ≤ 0.11%, respectively. Therefore, it is highly unlikely that consumers will be poisoned by CPPU due to kiwifruit consumption. Our results provide scientific evidence regarding the adoption of appropriate kiwifruit storage methods and consumption behavior to enhance consumption safety.
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BMC Pharmacology & Toxicology
·
2021
·Vol. 22
·期 1
·1-11
·
IF 2.483
Li Danni,Liu Shaogang,Zhu Jiahao,Shen Liqun,Zhang Qi ying,Zhu Hua
Background The development of novel and effective drugs for targeted human hepatocellular carcinoma still remains a great challenge. The alkaloid nitidine chloride (NC), a component of a traditional Chinese medicine, has been shown to have anticancer properties, but doses at therapeutic levels have unacceptable side effects. Here we investigate folic acid modified D-α-tocopheryl polyethylene glycol 1000 succinate (TPGS-FA) as a potential carrier for controlled delivery of the drug. Methods Synthesized TPGS-FA was characterized by FTIR, UV-visible and 1 H NMR spectroscopy, and TPGS loaded with NC was evaluated for its ability to induce apoptosis in Huh7 cells by Annexin V/PI and MTT assays, and observed by laser scanning confocal microscopy and inverted phase contrast microscopy. Results TPGS-FA/NC complexes were prepared successfully, and were homogenious with a uniform size of ~ 14 nm diameter. NC was released from the TPGS-FA/NC complexes in a controlled and sustained manner under physiological conditions (pH 7.4). Furthermore, its cytotoxicity to hepatocarcinoma cells was greater than that of free NC. Conclusions TPGS-FA is shown to be useful carrier for drugs such as NC, and TPGS-FA/NC could potentially be a potent and safe drug for the treatment of hepatocellular carcinoma.
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Scientific Reports
·
2020
·Vol. 10
·期 1
·1-12
·
IF 3.998
Chu Youqun,Huang Zhangkao,Wang Xinhang,Zhou Menglei,Zhao Fengming
We report the fabrication of silver nanoparticles evenly imbedded into TiN submicrospheres via one-pot solvothermal reaction and subsequent nitridation for electrochemical detecting of hydrogen peroxide. The precursor of TiO 2 submicrospheres and high dispersion of silver nanoparticles are regulated by the alcoholysis of tetrabutyl titanate and reducibility of enol in vitamin C. The ion nitriding promoted the conductivity and micro-nano porous structure on the surface of TiN submicrospheres, which increase the dispersity of silver nanoparticles and make contributions to avoid aggregations. More importantly, the electrochemical response of Ag-TiN submicrospheres to H 2 O 2 was remarkably enhanced due to the co-effects of Ag and N-doping. It provides a superior sensing performance for electrochemical detection of hydrogen peroxide at − 0.3 V with a high sensitivity of 33.25 μA mmol L −1 cm −2 , wide linear range of 0.05–2100 μM and low detection limit of 7.7 nM. The fabricated sensor also reliably applied in detection of H 2 O 2 in milk samples with good reproducibility, repeatability and storage stability.
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ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2020
·Vol. 28
·期 12
·15032-15042
·
IF 3.056
Zhao Zhilin,Xu Limei,Wang Yong,Li Bihan,Zhang Wenming,Li Xiaochen
Silver nanoparticles (Ag-NPs) are widely used in daily life and inevitably discharged into the aquatic environment, causing increasingly serious pollution. Research on the toxicity of Ag-NPs is still in infancy, little information is available on the relationships between oxidative stress and antioxidant, as well as damaging degrees of Ag-NPs to cellular structural components of Chlamydomonas reinhardtii ( C. reinhardtiii ). In the present study, we revealed the toxicity mechanism of C. reinhardtii under Ag-NPs stress using flow cytometry (FCM), metabolic methods, and transmission electron microscopy. The results showed that the chloroplasts were damaged and the synthesis of photosynthetic pigments was inhibited under Ag-NPs stress, which inhibited the growth of C. reinhardtii . Meanwhile, Ag-NPs also caused C. reinhardtii to produce excessive reactive oxygen species (ROS), increased malondialdehyde content and changed the permeability of cell membrane, resulting in the acceleration of internalization of Ag-NPs. The decrease of cell size and intracellular chlorophyll autofluorescence was observed with FCM. To deal with the induced excessive ROS that could lead to lethal and irreversible structure damage, C. reinhardtii activated antioxidant enzymes including superoxide dismutase and peroxidase. This study provides new information for better understanding the potential toxicity risks of Ag-NPs in the aquatic environment.
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