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81.
82.
Junhui Jia Pengchong Xue Yuan Zhang Qiuxia Xu Gonghe Zhang Tianhao Huang Hanzhuang Zhang Ran Lu 《Tetrahedron》2014
A new D-π-A dimesitylboron derivative with terminal phenothiazine bridged by fluorenevinyl (PFTB) has been synthesized. It was found that PFTB could selectively recognize fluoride and cyanide anions by naked eyes. Upon addition of F− and CN−, the color of the solution of PFTB in DCM turned to yellowish-green from yellow and strong green emitting was observed under UV light, while the emission of PFTB in DCM was weak. Moreover, the presence of 10 equiv of tetrabutylammonium salts of other anions, such as Cl−, Br−, I−, AcO−, HSO4−, H2PO4−, could not lead to obvious changes of the UV–vis absorption and the fluorescent emission spectra of PFTB. The detection limits of PFTB towards F− and CN− were 7.52×10−8 mol/L and 6.12×10−8 mol/L in DCM, respectively. Therefore, the D-π-A type triarylborane derivatives can be used as ‘turn on’ fluorescent sensors for detecting F− and CN−. 相似文献
83.
在磷酸催化作用下,采用前体二胺N,N’-(2-胺基苯基)-2,6-二甲酰亚胺吡啶(1)和前体二醛1,4-二(2’-甲酰苯氧基)丁烷(2)进行缩合作用得到[1+1]Schiff碱大环化合物3,进一步将Schiff碱大环3还原得到饱和大环4.并采用1H NMR,IR,质谱和元素分析等技术对大环3和4的组成进行了表征.采用X射线单晶衍射技术测定了Schiff碱大环3的晶体结构,结果表明大环3具有扭曲的"8"字形结构.采用UV-vis光谱滴定技术对大环与系列阴离子的键合作用进行了考察,结果表明,Schiff碱大环3对F-离子有明显的选择性识别作用,并测定了该配位反应的配位比和平衡常数. 相似文献
84.
Ultra‐fast LC–ESI‐MS/MS method for the simultaneous determination of six highly toxic Aconitum alkaloids from Aconiti kusnezoffii radix in rat plasma and its application to a pharmacokinetic study 下载免费PDF全文
Jingjing Liu Qing Li Yidi Yin Ran Liu Huarong Xu Kaishun Bi 《Journal of separation science》2014,37(1-2):171-178
A fast, sensitive, and efficient ultra‐fast LC–ESI‐MS/MS method was developed for the simultaneous quantitation of six highly toxic Aconitum alkaloids, that is, aconitine, mesaconitine, hypaconitine, benzoylaconine, benzoylmesaconine, and benzoylhypaconine, in rat plasma after oral administration of crude ethanol extracts from Aconiti kusnezoffii radix by ultrasonic extraction, reflux extraction for 1 h, and reflux extraction for 3 h, respectively. The separation of six Aconitum alkaloids and aminopyrine (internal standard) was performed on an InertSustain® C18 column, and the quantification of the analytes was performed on a 4000Q ultra‐fast LC–MS/MS system with turbo ion spray source in the positive ion and multiple‐reaction monitoring mode. Absolute recoveries ranged within 65.06–85.1% for plasma samples. The intra‐ and interday precision and accuracy of analytes were satisfactory. The methods were validated with sensitivity reaching the lower LOQ for aconitine, mesaconitine, hypaconitine, benzoylaconine, benzoylmesaconine, and benzoylhypaconine, which were 0.025, 0.025, 0.050, 0.025, 0.025, and 0.100 ng/mL, respectively. The method was successfully applied to a pharmacokinetic study of six Aconitum alkaloids in rat plasma after oral administration of crude ethanol extracts from the raw root of Aconitum kusnezoffii Reichb. by three different extraction processes. 相似文献
85.
Zhe Yao Xianglong Zhao Danni Ran Jacques Crommen Zhengjin Jiang 《Journal of separation science》2014,37(14):1720-1727
Derivatized β‐cyclodextrin (β‐CD) functionalized monolithic columns were prepared by a “one‐step” strategy using click chemistry. First, the intended derivatized β‐CD monomers were synthesized by a click reaction between propargyl methacrylate and mono‐6‐azido‐β‐CD and then sulfonation or methylation was carried out. Finally, monolithic columns were prepared through a one‐step in situ copolymerization of the derivatized β‐CD monomer and ethylene glycol dimethacrylate. The sulfated β‐CD‐based monolith was successfully applied to the hydrophilic interaction liquid chromatography separation of nucleosides and small peptides, while the methylated β‐CD‐functionalized monolith was useful for the separation of nonpolar compounds and drug enantiomers in capillary reversed‐phase liquid chromatography. The structures of the monomers were characterized by Fourier transform infrared spectroscopy and mass spectrometry. The physicochemical properties and column performance of monoliths were evaluated by scanning electron microscopy and micro high performance liquid chromatography. This strategy has considerable prospects for the preparation of other derivatized CD‐functionalized methacrylate monoliths. 相似文献
86.
Shuanglong Chen Mingguang Yao Ye Yuan Fengxian Ma Zhaodong Liu Bing Li Ran Liu Quanjun Li Bo Zou Tian Cui Bingbing Liu 《Journal of Raman spectroscopy : JRS》2015,46(4):400-405
Raman spectra of iodine species confined in one‐dimensional elliptical channels of AlPO4‐11 (AEL) crystals have been studied from room temperature down to −196 °C. As temperature decreases, thermal fluctuations of individual iodine molecules confined in AEL channels are slowed down and they prefer to rotate to channel axis direction, which increases the population of iodine molecules along channel axis (i.e., lying molecules and chains). Such temperature‐driven orientation transformation of iodine molecules is found to be reversible upon heating up to room temperature. The experimental observations are in good agreement with our theoretical simulations by molecular dynamics on low density iodine‐filled AEL crystals. We thus provide a new way to modulate the orientation of iodine molecules in nanochannels, which may have implications in low‐temperature‐sensitive nanoscale devices. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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89.
Bin Ran Chaozhan Chen Bo Liu Minbo Lan Huaying Chen Yonggang Zhu 《Electrophoresis》2022,43(20):2033-2043
The detection of cancer biomarkers is of great significance for the early screening of cancer. Detecting the content of sarcosine in blood or urine has been considered to provide a basis for the diagnosis of prostate cancer. However, it still lacks simple, high-precision and wide-ranging sarcosine detection methods. In this work, a Ti3C2TX/Pt–Pd nanocomposite with high stability and excellent electrochemical performance has been synthesized by a facile one-step alcohol reduction and then used on a glassy carbon electrode (GCE) with sarcosine oxidase (SOx) to form a sarcosine biosensor (GCE/Ti3C2TX/Pt–Pd/SOx). The prominent electrocatalytic activity and biocompatibility of Ti3C2TX/Pt–Pd enable the SOx to be highly active and sensitive to sarcosine. Under the optimized conditions, the prepared biosensor has a wide linear detection range to sarcosine from 1 to 1000 µM with a low limit of detection of 0.16 µM (S/N = 3) and a sensitivity of 84.1 µA/mM cm2. Besides, the reliable response in serum samples shows its potential in the early diagnosis of prostate cancer. More importantly, the successful construction and application of the amperometric biosensor based on Ti3C2TX/Pt–Pd will provide a meaningful reference for detecting other cancer biomarkers. 相似文献
90.
建立了高效液相色谱-四极杆-飞行时间质谱快速筛查鉴别食品中非法添加的62种中药材的方法。依据卫生部关于进一步规范保健食品原料管理的通知(卫法监发[2002]51号)中可用于保健食品的物品名单,确定食品中可能非法添加的62种中药材原料清单,再从62种中药材中筛选其特征组分,获得不同中药材对应的特征组分清单。62种对照药材经甲醇超声提取后,于Thermo Accucore aQ色谱柱(150 mm×2.1 mm,2.6μm)上分离,在电喷雾正负离子扫描模式下,分别以0.1%(v/v)甲酸水溶液-乙腈和水-乙腈为流动相梯度洗脱,进行一级质谱和二级质谱全扫描检测,采用Library View软件建立不同中药材对应的特征组分的一级精确质量数据库和二级碎片质谱库。样品同法处理后上样分析,采用Peak View软件将样品高分辨数据与自建数据库中的质谱图、精确分子离子质量数、碎片离子质量数、保留时间等相关参数进行快速筛查鉴别分析。该工作通过建立“中药材-特征组分”对应清单,构建了食品中易非法添加的62种中药材中共388种特征组分的高分辨质谱库,每种中药材包括5~10种特征组分,通过对实际食品样品配制酒、代用茶及饮料进行筛查分析,1批次配制酒样品与淫羊藿中药材的7种特征组分匹配一致,推断该配制酒样品中加入了淫羊藿中药材。该法可实现无标准品情况下中药材的定性筛查,具有高通量、准确、简便、快捷的特点,解决了食品中非法添加中药材难以识别和确证的难题,可以实现食品中非法添加中药材的快速筛查鉴别分析。 相似文献