halogenation

卤化
  • 文章类型: Journal Article
    现代纳米医学将多模式治疗整合到一个单一的配方中,提供创新的癌症治疗选择。纳米片作为载体,改变溶解度,生物分布,和药用化合物的有效性,导致更有效的癌症治疗和减少副作用。氟化氧化石墨烯(FGO)纳米片的无毒性质及其在药物递送中的潜在应用,医学诊断,生物医学将它们与其他人区分开来。利用Lissachatinafulica蜗牛粘液(LfSM)的独特特性,开发了FGO纳米片以揭示新颖的特性。因此,LfSM被用来制造无毒的,环保,和持久的FGO纳米片。紫外-可见(UV-vis)光谱显示出在235nm处的显著吸收峰。合成的FGO纳米片的表征包括X射线衍射(XRD),傅里叶变换红外光谱(FTIR),拉曼,扫描电子显微镜(SEM),X射线光电子能谱(XPS),高分辨率透射电子显微镜(HR-TEM),和原子力显微镜(AFM)分析。抗菌活性数据证明了对大肠杆菌的广谱抗菌作用,枯草芽孢杆菌,肺炎克雷伯菌,还有铜绿假单胞菌.LfSM-FGO纳米片对胰腺癌细胞系(PANC1)的细胞毒性功效在低浓度下显示出有希望的结果。该研究表明,由LfSM制成的FGO纳米片可以作为未来生物医学应用的替代因素。
    The modern nanomedicine incorporates the multimodal treatments into a single formulation, offering innovative cancer therapy options. Nanosheets function as carriers, altering the solubility, biodistribution, and effectiveness of medicinal compounds, resulting in more efficient cancer treatments and reduced side effects. The non-toxic nature of fluorinated graphene oxide (FGO) nanosheets and their potential applications in medication delivery, medical diagnostics, and biomedicine distinguish them from others. Leveraging the unique properties of Lissachatina fulica snail mucus (LfSM), FGO nanosheets were developed to reveal the novel characteristics. Consequently, LfSM was utilized to create non-toxic, environmentally friendly, and long-lasting FGO nanosheets. Ultraviolet-visible (UV-vis) spectroscopy revealed a prominent absorbance peak at 235 nm. The characterization of the synthesized FGO nanosheets involved X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Raman, scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), high-resolution transmission electron microscopy (HR-TEM), and atomic force microscopy (AFM) analyses. The antimicrobial activity data demonstrated a broad spectrum of antibacterial effects against Escherichia coli, Bacillus subtilis, Klebsiella pneumoniae, and Pseudomonas aeruginosa. The cytotoxicity efficacy of LfSM-FGO nanosheets against pancreatic cancer cell line (PANC1) showed promising results at low concentrations. The study suggests that FGO nanosheets made from LfSM could serve as alternate factors for in biomedical applications in the future.
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  • 文章类型: Journal Article
    氯化法通常用于对大型游乐园的娱乐用水进行消毒;但是,氯化消毒副产物(DBP)对职业人群的健康危害尚不清楚。这项研究旨在评估娱乐水中氯化DBPs的暴露状况以及对大型游乐园员工的健康风险。
    采用问卷调查法对上海三家大型游乐园员工的暴露参数进行了调查。通过气相色谱法定量了娱乐水和喷雾样品中的七个典型的氯化DBPs,根据WHO的风险评估框架,评估了暴露于氯化DBPs的游乐园员工的健康风险。
    三氯乙酸,二溴氯甲烷,溴二氯甲烷,和二氯乙酸主要在娱乐水中检测到。五个DBP的致癌和非致癌风险均未超过风险阈值。此外,DBP混合暴露的致癌和非致癌风险在可接受的风险限度内.
    在上海三个大型游乐园收集的休闲水中广泛检测到典型的DBPs;但是,DBP及其混合物的健康风险在可接受的范围内.
    UNASSIGNED: Chlorination is often used to disinfect recreational water in large amusement parks; however, the health hazards of chlorination disinfection by-products (DBPs) to occupational populations are unknown. This study aimed to assess the exposure status of chlorinated DBPs in recreational water and the health risks to employees of large amusement parks.
    UNASSIGNED: Exposure parameters of employees of three large amusement parks in Shanghai were investigated using a questionnaire. Seven typical chlorinated DBPs in recreational water and spray samples were quantified by gas chromatography, and the health risks to amusement park employees exposed to chlorinated DBPs were evaluated according to the WHO\'s risk assessment framework.
    UNASSIGNED: Trichloroacetic acid, dibromochloromethane, bromodichloromethane, and dichloroacetic acid were detected predominantly in recreational water. The carcinogenic and non-carcinogenic risks of the five DBPs did not exceed the risk thresholds. In addition, the carcinogenic and non-carcinogenic risks of mixed exposure to DBPs were within the acceptable risk limits.
    UNASSIGNED: Typical DBPs were widely detected in recreational water collected from three large amusement parks in Shanghai; however, the health risks of DBPs and their mixtures were within acceptable limits.
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  • 文章类型: Journal Article
    2017年,FDA批准5-氨基乙酰丙酸(5-ALA)用于可疑的高级别神经胶质瘤的术中光学成像。这是第一个授权的用于脑肿瘤手术的光学成像剂,可增强恶性组织的可视化。在这里,我们报道了5-ALA的外消旋和对映体纯的氟化类似物的合成,即,3-氟-5-氨基乙酰丙酸(3F-5-ALA)。我们预计这些研究将为未来构建用于神经胶质瘤功能和代谢成像的氟-18标记的5-ALAPET示踪剂奠定基础。
    In 2017, the FDA authorized 5-aminolevulinic acid (5-ALA) for intraoperative optical imaging of suspected high-grade gliomas. This was the first authorized optical imaging agent for brain tumor surgery to enhance the visualization of malignant tissue. Herein we report the synthesis of a racemic and enantiopure fluorinated analog of 5-ALA, i.e., 3-fluoro-5-aminolevulinic acid (3F-5-ALA). We anticipate that these studies will provide the foundation for the future construction of a fluorine-18-labeled 5-ALA PET tracer to be used for functional and metabolic imaging of gliomas.
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  • 文章类型: Journal Article
    含氮化合物是几乎所有化学工业中的有价值的合成中间体和目标。虽然形成氮-碳和氮-杂原子键的方法主要依赖于亲核氮原子反应性,含有氮-卤素键的分子允许在氮中心的亲电或自由基反应模式。尽管含氮-卤键化合物的合成效用不断增加,它们合成的选择性催化策略在很大程度上是不够的。我们最近发现,钒依赖性卤代过氧化物酶(VHPO)类酶是形成氮-卤键的合适生物催化剂平台。在这里,我们表明VHPOs对一系列取代的苄脒盐酸盐进行选择性卤化,以产生相应的N\'-卤代苯酰亚胺酰胺。该生物催化平台可用于由相应的N-酰基苄脒以高产率和优异的化学选择性合成1,2,4-恶二唑。最后,这种生物技术的合成适用性在氮-氮键形成和Duchenne肌营养不良药物的化学酶合成中得到了证明,Ataluren.
    Nitrogen-containing compounds are valuable synthetic intermediates and targets in nearly every chemical industry. While methods for nitrogen-carbon and nitrogen-heteroatom bond formation have primarily relied on nucleophilic nitrogen atom reactivity, molecules containing nitrogen-halogen bonds allow for electrophilic or radical reactivity modes at the nitrogen center. Despite the growing synthetic utility of nitrogen-halogen bond-containing compounds, selective catalytic strategies for their synthesis are largely underexplored. We recently discovered that the vanadium-dependent haloperoxidase (VHPO) class of enzymes are a suitable biocatalyst platform for nitrogen-halogen bond formation. Herein, we show that VHPOs perform selective halogenation of a range of substituted benzamidine hydrochlorides to produce the corresponding N\'-halobenzimidamides. This biocatalytic platform is applied to the synthesis of 1,2,4-oxadiazoles from the corresponding N-acylbenzamidines in high yield and with excellent chemoselectivity. Finally, the synthetic applicability of this biotechnology is demonstrated in an extension to nitrogen-nitrogen bond formation and the chemoenzymatic synthesis of the Duchenne muscular dystrophy drug, ataluren.
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  • 文章类型: Journal Article
    Pd基电催化加氢脱氯(EHDC)催化剂的结构调节对于构建具有低贵金属含量和高原子利用率的高效阴极材料至关重要,但仍然具有挑战性。在这里,提出了一种通过原位Mn掺杂优化泡沫Ni(NF)电子结构的Pd-Mn/Ni泡沫催化剂的载体电子感应效应,可以感应调节Pd,提高EHDC性能。以2,4-二氯苯酚为模型化合物,Pd-Mn/NF催化剂的质量活性和电流效率分别优于Pd/NF催化剂的2.91和1.34倍,分别。Mn掺杂的中间层通过使d状态比NF表面上的Pd更接近费米能级来优化Pd的电子结构,优化了EHDC中间体的结合。此外,Mn掺杂的中间层用作产生H*和加速EHDC反应的促进剂。这项工作提出了一种简单有效的调节策略,用于为氯化有机化合物的EHDC构建高效阴极催化剂。
    Structural regulation of Pd-based electrocatalytic hydrodechlorination (EHDC) catalyst for constructing high-efficient cathode materials with low noble metal content and high atom utilization is crucial but still challenging. Herein, a support electron inductive effect of Pd-Mn/Ni foam catalyst was proposed via in-situ Mn doping to optimize the electronic structure of the Ni foam (NF), which can inductive regulation of Pd for improving the EHDC performance. The mass activity and current efficiency of Pd-Mn/NF catalyst are 2.91 and 1.34 times superior to that of Pd/NF with 2,4-dichlorophenol as model compound, respectively. The Mn-doped interlayer optimized the electronic structure of Pd by bringing the d-state closer to the Fermi level than Pd on the NF surface, which optimizied the binding of EHDC intermediates. Additionally, the Mn-doped interlayer acted as a promoter for generating H* and accelerating the EHDC reaction. This work presents a simple and effective regulation strategy for constructing high-efficient cathode catalyst for the EHDC of chlorinated organic compounds.
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  • 文章类型: Journal Article
    在水处理过程中,氯化和紫外线(UV)灭菌可以改性微塑料(MPs)并改变其理化性质,导致国会议员和其他污染物之间的各种变化。在这项研究中,研究了氯化和紫外改性对聚苯乙烯(PS)和聚氯乙烯(PVC)理化性能的影响,并考察了改性前后培氟沙星(PEF)的吸附行为。pH的影响,离子强度,溶解的有机物,揭示了重金属离子等水环境条件对吸附行为的影响。结果表明,PS对PEF的吸附能力高于PVC,修饰增加了MP中含O官能团的存在,从而提高两种材料的吸附能力。氯化对MPs的理化性质的影响比紫外线照射在相同的时间内,导致更好的氯化吸附性能。发现吸附的最佳pH为6,NaCl,海藻酸钠和Cu2+会不同程度地抑制吸附,其中pH引起的抑制作用最强。氯化和紫外改性会削弱环境因素对MPs吸附PEF的抑制作用。吸附的主要机制涉及静电相互作用和氢键。研究阐明了改性对MPs理化性质的影响,为后续生物毒性分析和环境保护研究提供参考。
    During the water treatment process, chlorination and ultraviolet (UV) sterilization can modify microplastics (MPs) and alter their physicochemical properties, causing various changes between MPs and other pollutants. In this study, the impact of chlorination and UV modification on the physicochemical properties of polystyrene (PS) and polyvinyl chloride (PVC) were investigated, and the adsorption behavior of pefloxacin (PEF) before and after modification was examined. The effect of pH, ionic strength, dissolved organic matter, heavy metal ions and other water environmental conditions on adsorption behavior was revealed. The results showed that PS had a higher adsorption capacity of PEF than PVC, and the modification increased the presence of O-containing functional groups in the MPs, thereby enhancing the adsorption capacity of both materials. Chlorination had a more significant impact on the physicochemical properties of MPs compared to UV irradiation within the same time period, leading to better adsorption performance of chlorination. The optimal pH for adsorption was found to be 6, and NaCl, sodium alginate and Cu2+ would inhibit adsorption to varying degrees, among which the inhibition caused by pH was the strongest. Chlorination and UV modification would weaken the inhibitory effect of environmental factors on the adsorption of PEF by MPs. The main mechanisms of adsorption involved electrostatic interaction and hydrogen bonding. The study clarified the effects of modification on the physicochemical properties of MPs, providing reference for subsequent biotoxicity analysis and environmental protection studies.
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  • 文章类型: Journal Article
    对羟基苯甲酸酯被归类为全球水域中的新兴污染物,其高氯废水消毒产生的高风险氯化产物的普遍存在引起了越来越多的关注。然而,在排放到地表水中之后,关于它们的光子的信息相当有限,太阳能工程水处理后它们的降解行为尚不清楚。在这里,测量了四种氯化对羟基苯甲酸酯与不同光化学产生的反应性中间体的反应性。减少此类化合物的定量贡献分析显示,在阳光照射的天然淡水中,直接光解占主导地位。引入技术太阳能/过氧单硫酸盐(PMS)系统可以大大提高氯化对羟基苯甲酸酯的去除。经济分析表明,氯化对羟基苯甲酸酯在0.543-0.950mMPMS下的经济投入最小值为93.41-158.04kWhm-3order-1。降解产物的高分辨率质谱分析表明脱氯,羟基化,和酯链裂解是光解和太阳能/PMS处理期间的主要转化途径。此外,计算机预测表明某些产品具有严重的水生毒性,但可生物降解性增强。总的来说,这项调查填补了有关氯化对羟基苯甲酸酯具有多种反应性瞬变的反应性及其对水中新兴微污染物的光解和太阳能/PMS处理的定量贡献的知识空白。
    Parabens are classified as emerging contaminants in global waters, and the ubiquitous emergence of their high-risk chlorinated products generated from chlorine-based wastewater disinfection has attracted increasing attention. However, rather limited information is available on their photofate after discharging into surface waters, and their degradation behavior after solar-based engineering water treatment is unclear. Herein, the reactivity of four chlorinated parabens with different photochemically produced reactive intermediates was measured. Quantitative contribution analysis in abating such compounds showed the dominance of direct photolysis in sunlit natural freshwaters. Introducing a technical solar/peroxymonosulfate (PMS) system could greatly improve the removal of chlorinated parabens. The economic analysis suggested that chlorinated parabens exhibited a minimum value of economic input as 93.41-158.04 kWh m-3 order-1 at 0.543-0.950 mM PMS. The high-resolution mass spectrometry analysis of the degradation products suggested that dechlorination, hydroxylation, and ester chain cleavage were the dominant transformation pathways during photolysis and solar/PMS treatment. Furthermore, the in silico prediction indicated severe aquatic toxicity of certain products but enhanced biodegradability. Overall, this investigation filled a knowledge gap on the reactivity of chlorinated parabens with diverse reactive transients and their quantitative contributions to the photolysis and solar/PMS treatment of emerging micropollutants in water.
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  • 文章类型: Journal Article
    N-乙酰乳糖胺是在各种生物活性聚糖中发现的常见糖基序。该基序通常作为额外修饰的骨架起作用,因此显著影响聚糖构象行为和生物活性。在这项工作中,我们已经研究了2型N-乙酰乳糖胺支架,使用其完整系列的单脱氧氟化类似物。这些糖模拟物已经通过分子力学进行了研究,量子力学,X射线晶体学,和各种核磁共振技术,它们提供了对单个羟基在N-乙酰基乳糖胺的构象行为和亲脂性中的作用的全面而完整的见解。
    N-Acetyllactosamine is a common saccharide motif found in various biologically active glycans. This motif usually works as a backbone for additional modifications and thus significantly influences glycan conformational behavior and biological activity. In this work, we have investigated the type-2 N-acetyllactosamine scaffold using the complete series of its monodeoxyfluorinated analogs. These glycomimetics have been studied by molecular mechanics, quantum mechanics, X-ray crystallography, and various NMR techniques, which have provided a comprehensive and complete insight into the role of individual hydroxyl groups in the conformational behavior and lipophilicity of N-acetyllactosamine.
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  • 文章类型: Journal Article
    去除Mn(II)是解决全球水处理设施中的水变色的重要步骤。然而,传统的氯化由于其均相氧化动力学低,因此Mn(II)的氧化性差。这项研究探索了采用过氧单硫酸盐(PMS)辅助氯化过程(PMS@Cl2)进行有效Mn(II)氧化的新化学加药策略的氧化能力。该研究全面探索了PMS@Cl2系统中与均相和非均相氧化相关的氧化动力学和潜在机制。在[Mn(II)]0为1mg/L时,氯化证明不能氧化Mn(II),即使在150μM(~10mg/L)的升高的[Cl2]下,氧化也<10%。相比之下,PMS在30分钟的反应中完全氧化了100%Mn(II),在60μM的更低的[PMS](kobs=0.07min-1和t1/2=9min),证明了其优越的Mn(II)氧化动力学(比常规氯快一个数量级)。当将较低剂量的PMS与较高常规剂量的Cl2(loPMS@hiCl2)组合时,PMS@Cl2表现出有趣的协同益处,例如,15:30或30:30μM的[PMS]:[Cl2]。两种条件均实现100%Mn(II)氧化,在60µM时,相对于单独的PMS,kobs和t1/2(0.16-0.17min-1和~4min)的值甚至更好。PMS@Cl2的协同益处归因于PMS和Cl2在均相和非均相氧化过程中发挥的不同功能。反应性物种鉴定排除了SO4·-的可能参与,OH•,或PMS@Cl2系统的均相氧化中的氯自由基。相反,主要物种是Mn(II)与PMS反应过程中产生的O2•-自由基。此外,非均相氧化强调了结合Cl2加药的重要作用,这表明与Mn-O-Mn络合物的反应性和电子转移增加,超越PMS。总的来说,相对于单独的Cl2的均匀氧化,非均相氧化将PMS@Cl2系统的氧化动力学加速了1.1-2个数量级。我们在这里证明了PMS@Cl2可以提供更有效的可溶性Mn(II)缓解方法,在较短的反应时间内使用相对较低的常规氧化剂剂量实现。这项研究的结果将解决传统氯氧化的现有局限性,在处理可溶性含锰水后,最大限度地减少与高余氯水平相关的权衡。
    Removal of Mn(II) is an essential step for addressing water discoloration in water treatment utilities worldwide. However, conventional chlorination suffers from poor oxidation of Mn(II) due to its low homogeneous oxidation kinetics. This study explored the oxidation capability of a new chemical dosing strategy employing peroxymonosulfate (PMS) to assist the chlorination process (PMS@Cl2) for effective Mn(II) oxidation. The study comprehensively explored both oxidation kinetics and underlying mechanisms associated with homogeneous and heterogeneous oxidation within the PMS@Cl2 system. At an [Mn(II)]0 of 1 mg/L, chlorination demonstrated inability in oxidizing Mn(II), with <10 % oxidation even at an elevated [Cl2] of 150 μM (∼10 mg/L). By contrast, PMS completely oxidized 100 % Mn(II) within a 30-minute reaction at a much lower [PMS] of 60 μM (kobs = 0.07 min-1 and t1/2 = 9 min), demonstrating its superior Mn(II) oxidation kinetics (over one order of magnitude faster than conventional chlorine). PMS@Cl2 exhibited an interesting synergistic benefit when combining a lower dose PMS with a higher routine dose Cl2 (loPMS@hiCl2), e.g. [PMS]:[Cl2] at 15:30 or 30:30 μM. Both conditions achieved 100 % Mn(II) oxidation, with even better values of kobs and t1/2 (0.16-0.17 min-1 and ∼4 min) relative to PMS alone at 60 µM. The synergic benefit of PMS@Cl2 was attributed to distinct functions played by PMS and Cl2 in both homogeneous and heterogeneous oxidation processes. Reactive species identification excluded the possible involvement of SO4•-, OH•, or chlorine radicals in the homogeneous oxidation of the PMS@Cl2 system. Instead, the dominant species was O2•- radical generated during the reaction of Mn(II) and PMS. Furthermore, the heterogeneous oxidation emphasized the important role of combining Cl2 dosing, which demonstrated an increased reactivity and electron transfer with the Mn-O-Mn complex, surpassing PMS. Overall, heterogeneous oxidation accelerated the oxidation kinetics of the PMS@Cl2 system by 1.1-2 orders of magnitude relative to the homogeneous oxidation of Cl2 alone. We here demonstrated that PMS@Cl2 could offer a more efficient mean of soluble Mn(II) mitigation, achieved with a relatively low routine dose of oxidant in a short reaction period. The outcomes of this study would address the existing limitations of traditional chlorine oxidation, minimizing the trade-offs associated with high residual chlorine levels after treatments for soluble manganese-containing water.
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  • 文章类型: Journal Article
    在静态海洋环境中开发无毒防污涂料迫在眉睫。在这里,报道了用自由基聚合法成功合成磺基甜菜碱冰片氟化聚合物(PEASBF)。PEASBF涂层具有出色的防污活性,有效抵抗牛血清白蛋白(FITC-BSA粘附率:0.5%)的粘附,假单胞菌。(生物膜:1.3吸光度)和Naviculasp。(硅藻附着率:33%)。更重要的是,PEASBF涂层显示出众的污垢释放性能,Naviculasp.的释放率为98%。,和假单胞菌的吸光度。在10Pa的剪切应力下,生物膜仅为0.2。XPS和MD研究表明,氟化/异冰片基诱导更多的磺基甜菜碱基团向聚合物表面迁移,以增强防污作用。此外,冰片的手性立体化学结构增强了两亲性聚合物的防污和防污释放能力。因此,PEASBF具有静态海洋防污应用的潜力。
    The development of nontoxic antifouling coatings in static marine environments is urgent. Herein, the successful synthesis of sulfobetaine borneol fluorinated polymers (PEASBF) by a free radical polymerization method is reported. The PEASBF coatings exhibit outstanding antifouling activity, which effectively resists the adhesion of Bovine serum albumin (FITC-BSA adhesion rate: 0.5%), Pseudomonas sp. (Biofilm: 1.3 absorbance) and Navicula sp. (Diatom attachment rate: 33%). More importantly, the PEASBF coatings display outstanding fouling release properties, achieving a release rate of 98% for Navicula sp., and the absorbance of the Pseudomonas sp. biofilm is only 0.2 under 10 Pa shear stress. XPS and MD studies showed that the fluorinated/isobornyl groups induce more sulfobetaine groups to migrate toward polymer surfaces for intensify antifouling. Additionally, the chiral stereochemical structure of borneol enhances antifouling and fouling release ability of amphiphilic polymers. Therefore, the PEASBF has the potential for static marine antifouling applications.
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