Drug Testing and Analysis
·
2022
·
IF 3.234
Te Xu,Zhen-Yu Niu,Jing Xu,Xin-Duo Li,Quan Luo,An Luo,Yi-Lan Huang,Xing-Tao Jiang,Ze-Hong Wu
Use of electronic cigarettes (e-cigarettes) has increased significantly over the past decade due to consumer perception that these products represent a less risky alternative to combustible cigarettes. E-liquids generally contain a simple mix of vegetable glycerin, propylene glycerol, nicotine, organic acids, and flavourings. Regulators require that harmful and potentially harmful constituents (HPHCs) that might cause harm to the consumer must be monitored in the aerosol generated by e-cigarettes and in cigarette smoke (CS). To quantify HPHCs in aerosols from commercial flavoured e-cigarettes in Chinese market, this study has systematically compared levels of HPHCs, including eight carbonyls, five volatile organic compounds, four tobacco-specific nitrosamines, 16 polycyclic aromatic hydrocarbons, and seven heavy metals, in the aerosols of four market-leading flavoured e-cigarettes and mainstream CS, alongside in vitro cytotoxicity and mutagenicity assays. The vast majority of HPHCs were either undetected or significantly lower in the e-cigarette aerosols than in commercial CS or reference CS (3R4F). Where HPHCs were detected, there were small variations among the different flavoured e-cigarettes. In the neutral red uptake and Ames assays, aqueous extracts of the e-cigarette aerosols did not induce obvious cytotoxicity or mutagenicity, whereas CS aqueous extract showed dose-related cytotoxicity and mutagenicity. Collectively, these results indicate that use of e-cigarettes might potentially lead to a significant reduction in exposure to harmful substances, with fewer cytotoxic and mutagenic effects, as compared with conventional smoking. Further studies based on human puffing conditions and longer evaluation periods will be needed to substantiate this potential.
研究领域:
毒理学
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公共卫生
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烟草控制
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化学分析
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产品关联
DOI
PubMed
高影响因子
Drug Testing and Analysis
·
2022
·Vol. 15
·期 10
·1099-1106
·
IF 3.234
Shulei Han,Chuan Liu,Huan Chen,Ya'ning Fu,Yuan Zhang,Ruijuan Miao,Peipei Ren,Pengpeng Yu,Zhihao Shi,Yushan Tian,Hongjuan Wang,Tong Liu,Hongwei Hou,Qingyuan Hu
Nicotine lactate, nicotine tartrate, nicotine benzoate, and freebase nicotine (FBN) are four forms of nicotine salt systems that are present in tobacco products. However, few in vivo studies have compared their pharmacological (pK) efficacies, which are important for understanding their roles in the addiction and abuse of tobacco and nicotine products. In this work, the pK of the above nicotine salt systems was studied by subcutaneously injecting their aqueous solutions in rats and obtaining blood samples from the jugular vein. Nicotine levels in the blood were analyzed by LC–MS/MS. The results demonstrated that rapid nicotine absorption occurred in all nicotine systems. Of them, NB had the smallest T max , while FBN had the largest T max . The nicotine metabolic rate and clearance decreased for FBN, indicating that nicotine retention in the body was higher than for the other three salt-based systems. Compared with nicotine salts, FBN could reach and maintain a higher concentration in the animal model. Additionally, as the benzoic acid ratios increased, the C max of the nicotine benzoate (NB) in the plasma decreased. This indicates that the lower the pH, the lower the C max . When different concentrations of NB were used, the higher the NB concentration, the greater the C max and AUC (0-t) . These results demonstrate that nicotine adsorption by NB in the animal model depended on both pH and concentration. This baseline information could be used to explain different clinical pharmacological observations in humans, though this study only considered the effects of nicotine on pharmacokinetics in vivo.
研究领域:
毒理学
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药理学
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产品关联
DOI
PubMed
高影响因子
Journal of Environmental Chemical Engineering
·
2025
·
IF 7.2
Xiaodan Wu,Chengdong Nie,Mengqiong Deng,Linan Sun,Ying Wang,Jingru Zhao,Yujie Fu,Yourong Duan,Ying Sun
In this study, natural polysaccharides were first modified to synthesize natural functional monomers (NFMs). Subsequently, a natural novel NFM-based imprinted hydrogel microsphere was prepared for the specific recognition and enrichment of 7-xylulose-10-deacetylpaclitaxel (7-X-10-DTA). Molecular dynamics computational simulations were employed to screen and compare the functional monomers. Subsequently, the optimal preparation and application conditions of NMIHM were determined, with a maximum adsorption capacity of 71.77 mg mL −1 . The adsorption behavior of NMIHM for 7-X-10-DTA conforms to the pseudo-second-order kinetic model and the Langmuir model for monolayer adsorption, representing a spontaneous exothermic process. When used as a solid-phase extraction filler, NMIHM increased the content of 7-X-10-DTA by 13.36 times after enrichment in Taxus × media Rehde. The 7-X-10-DTA extracted in this study exhibited low half-maximal inhibitory concentration (IC50) values of 0.3205 μM and 0.7636 μM against cervical cancer Hela cells and prostate cancer PC-3 cells, respectively, demonstrating a more potent killing effect on these two types of cancer cells. This research is expected to accelerate the research and development of natural functional monomers and the advancement of molecular imprinting technology, thereby promoting the rapid development of practical separation applications.
研究领域:
药学
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生物化学
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分离科学与技术
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产品关联
DOI
高影响因子
Polymers
·
2024
·Vol. 16
·期 23
·3254
·
IF 4.7
Jiaqi Wang,Zhaoyutian Chu,Sijia Zheng
Considering the demand for the construction of a sustainable future, it is essential to endow the conventional thermoset silicone adhesive with reuse capability and recyclability. Although various research attempts have been made by incorporating reversible linkages, developing sustainable silicone adhesives by natural linkers is still challenging, as the interface between the natural linker and the silicone is historically difficult. We exploited the possibility of utilizingα-lipoic acid, a natural linker, to construct a sustainable silicone adhesive. Via the simultaneous ring-opening reaction between the COOH and epoxide-functionalized silicone and the polymerization of theα-lipoic acid, the resulting network exhibited dynamic properties. The shear strength of the LASA90 presented strong adhesion (up to 88 kPa) on various substrates including steel, aluminum, PET, and PTFE. Meanwhile, reversible adhesion was shown multiple times under mild heating conditions (80 °C). The rheology, TG-DTA, DSC, and1H NMR showed that the degradation of the LASA occurred at 150 °C via the retro-ROP of the five-membered disulfide ring, indicating their recyclability after usage. Conclusively, we envision that a silicone adhesive based onα-lipoic acid as a natural linker is more sustainable than conventional silicone thermosets because of its desired properties, strong adhesion, reversibility, and on-demand heat degradation.
研究领域:
材料科学
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化学工程
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可持续发展
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粘合技术
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聚合物化学
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产品关联
DOI
PubMed
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2013
·
IF 5.825
Xing Tang,Huawei Chen,Lei Hu,Weiwei Hao,Yong Sun,Xianhai Zeng,Lu Lin,Shijie Liu
A series of low-cost readily-assembled eco-friendly metal hydroxides were examined as catalysts in the synthesis of a novel platform molecule, γ-valerolactone (GVL), from biomass-derived ethyl levulinate (EL) via hydrogen transfer reaction. Among these catalysts, ZrO(OH) 2 · x H 2 O was found to be most active. EL conversion of 93.6% and GVL selectivity of 94.5% were achieved when 2-propanol was used as a hydrogen donor at 473 K with a reaction time of only 1 h. The complete reaction pathway and the probable main by-products for the conversion of EL to GVL were clearly deduced for the first time. The ZrO(OH) 2 · x H 2 O catalyst could be reused at least ten times without any significant loss of catalytic activity. Furthermore, characterizations were carried out on the fresh and spent ZrO(OH) 2 · x H 2 O catalysts with XRD, FT-IR, BET, TGA-DTA. Combined with the results of poisoning experiments, a plausible mechanism for catalytic transfer hydrogenation (CTH) of EL to GVL was proposed to be consisted of a catalytic cycle involving a six member ring transition state.
研究领域:
化学工程
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催化
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绿色化学
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可再生能源
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产品关联
DOI
高影响因子
Nano Research
·
2023
·
IF 9.9
Peng Yiwei,Yang Yiliang,Yang Zhenzhen,Gao Datong,Li Jiajia,Sun Qi,Du Yitian,Lin Meng,Qi Xianrong
Immunotherapy has great promise in improving malignant tumor treatment. However, the efficacy of existing strategies is often limited by the immunosuppressive environment. Here, we demonstrate an in situ bionic immunoactivator, PLT-Bec1/DTA-1, with possessed natural advantages of platelets for tumor recruitment and activation, on which DTA-1 (CD357 monoclonal antibody) and Bec1 were tethered as combined immune boosters. PLT-Bec1/DTA-1, as a self-triggered release repository, can deliver the pre-tethered Bec1 and DTA-1 deeply through the secretion of platelet microparticles (PMPs), thereby cooperate tacitly and exhibit superiority in immune activation of dendritic cells (DCs) and T cells via autophagy inducibility, coupled with glucocorticoid-induced tumor necrosis factor receptor (GITR)-triggered T Reg suppression, remodeled the immunosuppressive network of tumor microenvironment. PLT-Bec1/DTA-1 promoted antigen presentation and T cell proliferation, and alleviated the low activity state of bone marrow-derived dendritic cells (BMDCs) in tumor suppressive environment. PLT-Bec1/DTA-1 inhibited tumor recurrence (5- and 13-fold lower of control group in tumor volume) and CD8 + T/T Reg ratio (6.3- and 8.8-fold vs. control group) in mouse tumor model after intravenous or subcutaneous administration. Also, PLT-Bec1/DTA-1 prevented tumor colonization in lung through in situ immune activation, and was slightly superior to the combined of Bec1 and PD-L1. Our findings highlight the promise of delivering immunostimulatory payloads via bionic carriers, eliciting automatic in situ activation of effector immune cells in tumor microenvironment for tumor eradication. All these results provide promising prospects into the application of immunoactivator in improving cancer synergistic immunotherapy to overcome the bottlenecks in clinic.
研究领域:
癌症免疫治疗
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生物医学工程
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分子生物学
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免疫学
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产品关联
DOI
高影响因子
Food Analytical Methods
·
2021
·Vol. 14
·期 11
·2308-2316
·
IF 3.366
Yuan Wei,Lu Lixia,Lu Yichen,Xiong Xiong,Li Yi,Cui Xiaowen,Liu Yuanjian,Xiong Xiaohui
Ochratoxin A (OTA) is considered as one of the most hazardous mycotoxins commonly occurring in grains. Thus, the monitoring of OTA is extremely significant. Herein, a synergistic strategy to detect OTA in grains based on the combination of DNA tetrahedron-structured aptamer (DTA) and hybridization chain reaction (HCR) was proposed. Briefly, DTA was assembled on the gold electrode. In the presence of OTA, the trigger DNA on the top of the DTA was exposed to unfold the biotin-modified hairpin structure DNA to HCR. It could conjugate plentiful streptavidin-labeled horseradish peroxidase (SA-HRP) to form polyaniline (PANI), which was regarded as electrochemical active molecule to detect OTA. In this way, the synergistic effect of DTA and HCR not only can provide stable probe structure to improve the recognition rate of OTA, but also can supply a large number of templates to synthesize PANI under mild conditions. As a result, the biosensor has a good analytical performance for OTA in a linear range of 0.05 to 50 ng mL −1 , with a detection limit of 0.017 ng mL −1 . The accuracy of sensor is similar with high-performance liquid chromatography (HPLC) analysis.
研究领域:
分析化学
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生物传感器
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毒理学
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食品安全
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产品关联
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2022
·Vol. 47
·期 3
·1216-1225
·
IF 3.925
Anqi Niu,Hang Xu,Qinlin Yuan,Fengmin Wu,Xuefeng Wei
Lewis acidic ionic liquid-loaded Fe3O4@SiO2 magnetic catalytic microspheres were prepared. When coupled with persulfate, the microspheres catalytically oxidized and removed dibenzothiophene (DBT) from octane. The microspheres used for catalytic desulfurization were characterized and analyzed by SEM, TEM, FT-IR, VSM, and TG-DTA. The results indicated that the prepared catalytic desulfurization microspheres had a uniform particle size distribution, an overall diameter of 200 nm, and a core diameter of Fe3O4 of about 180 nm. The saturation magnetization of the catalytic desulfurization microspheres was 39.8 emug−1, which allowed them to be rapidly magnetically separated. The optimal experimental conditions were 1.5 g catalyst, 1.2 g PMS (20%) oxidant, 30 °C, an initial sulfur content of 500 ppm, 6.0 g octane, and 3.0 g acetonitrile. Under these conditions, the desulfurization rate reached 98.5% after 25 min, which decreased by about 10% after five recycles. GC-MS analysis indicated the oxidation product was dibenzothiophene sulfone (DBTO2). In the desulfurization mechanism, DBT was first extracted by acetonitrile. Then, in the acetonitrile phase, Co2+ catalyzed hydrogen persulfate to form active oxygen atoms that oxidized DBT and eventually formed DBTO2.
研究领域:
化学工程
·
环境科学
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材料科学
·
分析化学
✓ 已验证
DOI
高影响因子
Journal of Energetic Materials
·
2024
·
IF 1.7
Ying Wu,Yong Liu,Shuai Hou,Qizhi Zhao,Han Gao,Xiao Yan
4,4’-Azo-1,2,4-triazole (atrz) is a new high nitrogen energetic material with high energy density, high gas yield and wide application prospects, but the low synthesis temperature and long time are the main reasons limiting its application. To achieve efficient synthesis of atrz, the double drop synthesis method was designed to solve the problem of unstable concentration of oxidant (HClO) due to batch feeding. The reaction temperature, reaction time, and molar ratio of reactants of n(4-amino-1,2,4-triazole):n(ClO−) were studied and optimized using the single factor variable method; Characterization and analysis of atrz using theoretical calculations with elemental analysis, infrared spectroscopy, crystal morphology, and nuclear magnetic resonance; The thermal properties and stability of atrz were tested and analyzed using TG-DTA. The results showed that the reaction time of the double drop synthesis method was shortened from 5 hours to 1.5 hours under the conditions of similar yield, and the efficiency was increased by 2.3 times. The optimized process was a reaction temperature of 5°C-10°C, reaction time of 1.5 hours, n(4-amino-1,2,4-triazole):n(ClO−) of 1:2, and the yield reached 73%. The product was white, needle-like crystals, which were determined to be atrz by means of characterization and theoretical calculations. Atrz’s decomposition peak temperature is 309.0°C, and when the temperature is below 271.7°C, atrz is thermally stable. The activation energies of atrz calculated by Kissinger and Flynn-Wall-Ozawa methods were 195.0 kJ·mol−1 and 194.6 kJ·mol−1.
研究领域:
化学
·
材料科学
·
能材料
·
理论计算
·
热分析
✓ 已验证
DOI
高影响因子
Journal of Materials Chemistry A
·
2015
·Vol. 3
·期 10
·5608-5616
·
IF 7.443
Chan Wang,Miao Yang,Peng Tian,Shutao Xu,Yue Yang,Dehua Wang,Yangyang Yuan,Zhongmin Liu
A spherical self-assembly of SAPO-34 nanosheets was hydrothermally synthesized by using a quaternary ammonium-type organosilane surfactant [3-(trimethoxysilyl)propyl]octadecyldimethylammonium chloride (TPOAC) as the mesoporogen and a part of the silica source, and diethylamine (DEA) as the microporous template. The prepared materials were well characterized by XRD, XRF, SEM, TEM, N2 adsorption–desorption, NH3-TPD, NH3-adsorbed IR and pyridine-adsorbed IR measurements. It revealed that the morphologies, compositions and acidity of the SAPO-34 products changed significantly with the increased TPOAC/TEOS ratio, showing that the TPOAC/TEOS ratio had a significant impact on the crystallization process of SAPO-34. Solid state 13C, 29Si NMR and TG-DTA analyses were further conducted to investigate the status of TPOAC in the final products. A possible crystallization process involving TPOAC was proposed. The catalytic performances of the synthesized SAPO-34s were evaluated using the MTO reaction. The optimal SAPO-34 nanosheet assemblies with a hierarchical porous structure displayed a remarkably enhanced catalytic lifetime and high yields of light olefins.
研究领域:
材料科学
·
化学工程
·
催化
·
无机化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）